From ef7ab92de7155864c0a6cca7783bcaea43e5be02 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 7 Apr 2020 19:15:29 +1000 Subject: [PATCH 01/24] ATmegaxxxx - initial commit --- portable/GCC/ATmegaxxxx/port.c | 741 ++++++++++++++++++++++++++++ portable/GCC/ATmegaxxxx/portmacro.h | 139 ++++++ 2 files changed, 880 insertions(+) create mode 100644 portable/GCC/ATmegaxxxx/port.c create mode 100644 portable/GCC/ATmegaxxxx/portmacro.h diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c new file mode 100644 index 0000000000..fe1709788a --- /dev/null +++ b/portable/GCC/ATmegaxxxx/port.c @@ -0,0 +1,741 @@ +/* + * FreeRTOS Kernel V10.3.1 + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * http://www.FreeRTOS.org + * http://aws.amazon.com/freertos + * + * 1 tab == 4 spaces! + */ + + +#include +#include +#include + +#include "FreeRTOS.h" +#include "task.h" + +/*----------------------------------------------------------- + * Implementation of functions defined in portable.h for the AVR port. + *----------------------------------------------------------*/ + +/* Start tasks with interrupts enabled. */ +#define portFLAGS_INT_ENABLED ( (StackType_t) 0x80 ) + +#if defined( portUSE_WDTO) + #warning "Watchdog Timer used for scheduler." + #define portSCHEDULER_ISR WDT_vect + +#elif defined( portUSE_TIMER0 ) +/* Hardware constants for Timer0. */ + #warning "Timer0 used for scheduler." + #define portSCHEDULER_ISR TIMER0_COMPA_vect + #define portCLEAR_COUNTER_ON_MATCH ( (uint8_t) _BV(WGM01) ) + #define portPRESCALE_1024 ( (uint8_t) (_BV(CS02)|_BV(CS00)) ) + #define portCLOCK_PRESCALER ( (uint32_t) 1024 ) + #define portCOMPARE_MATCH_A_INTERRUPT_ENABLE ( (uint8_t) _BV(OCIE0A) ) + #define portOCRL OCR0A + #define portTCCRa TCCR0A + #define portTCCRb TCCR0B + #define portTIMSK TIMSK0 + #define portTIFR TIFR0 + +#endif + +/*-----------------------------------------------------------*/ + +/* We require the address of the pxCurrentTCB variable, but don't want to know +any details of its type. */ +typedef void TCB_t; +extern volatile TCB_t * volatile pxCurrentTCB; + +/* actual number of ticks per second, after configuration. */ +TickType_t portTickRateHz; + +/* remaining ticks in each second, decremented to enable the system_tick. */ +volatile TickType_t ticksRemainingInSec; + +/*-----------------------------------------------------------*/ +/* + * Perform hardware setup to enable ticks from timer compare match A. + */ +static void prvSetupTimerInterrupt( void ); + +/*-----------------------------------------------------------*/ + +/** + Enable the watchdog timer, configuring it for expire after + (value) timeout (which is a combination of the WDP0 + through WDP3 bits). + + This function is derived from but enables only + the interrupt bit (WDIE), rather than the reset bit (WDE). + + Can't find it documented but the WDT, once enabled, + rolls over and fires a new interrupt each time. + + See also the symbolic constants WDTO_15MS et al. + + Updated to match avr-libc 2.0.0 +*/ + +static __inline__ +__attribute__ ((__always_inline__)) +void wdt_interrupt_enable (const uint8_t value) +{ + if (_SFR_IO_REG_P (_WD_CONTROL_REG)) + { + __asm__ __volatile__ ( + "in __tmp_reg__,__SREG__" "\n\t" + "cli" "\n\t" + "wdr" "\n\t" + "out %0, %1" "\n\t" + "out __SREG__,__tmp_reg__" "\n\t" + "out %0, %2" "\n\t" + : /* no outputs */ + : "I" (_SFR_IO_ADDR(_WD_CONTROL_REG)), + "r" ((uint8_t)(_BV(_WD_CHANGE_BIT) | _BV(WDE))), + "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | + _BV(WDIF) | _BV(WDIE) | (value & 0x07)) ) + : "r0" + ); + } + else + { + __asm__ __volatile__ ( + "in __tmp_reg__,__SREG__" "\n\t" + "cli" "\n\t" + "wdr" "\n\t" + "sts %0, %1" "\n\t" + "out __SREG__,__tmp_reg__" "\n\t" + "sts %0, %2" "\n\t" + : /* no outputs */ + : "n" (_SFR_MEM_ADDR(_WD_CONTROL_REG)), + "r" ((uint8_t)(_BV(_WD_CHANGE_BIT) | _BV(WDE))), + "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | + _BV(WDIF) | _BV(WDIE) | (value & 0x07)) ) + : "r0" + ); + } +} + +/*-----------------------------------------------------------*/ +/** + Enable the watchdog timer, configuring it for expire after + (value) timeout (which is a combination of the WDP0 + through WDP3 bits). + + This function is derived from but enables both + the reset bit (WDE), and the interrupt bit (WDIE). + + This will ensure that if the interrupt is not serviced + before the second timeout, the AVR will reset. + + Servicing the interrupt automatically clears it, + and ensures the AVR does not reset. + + Can't find it documented but the WDT, once enabled, + rolls over and fires a new interrupt each time. + + See also the symbolic constants WDTO_15MS et al. + + Updated to match avr-libc 2.0.0 +*/ + +static __inline__ +__attribute__ ((__always_inline__)) +void wdt_interrupt_reset_enable (const uint8_t value) +{ + if (_SFR_IO_REG_P (_WD_CONTROL_REG)) + { + __asm__ __volatile__ ( + "in __tmp_reg__,__SREG__" "\n\t" + "cli" "\n\t" + "wdr" "\n\t" + "out %0, %1" "\n\t" + "out __SREG__,__tmp_reg__" "\n\t" + "out %0, %2" "\n\t" + : /* no outputs */ + : "I" (_SFR_IO_ADDR(_WD_CONTROL_REG)), + "r" ((uint8_t)(_BV(_WD_CHANGE_BIT) | _BV(WDE))), + "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | + _BV(WDIF) | _BV(WDIE) | _BV(WDE) | (value & 0x07)) ) + : "r0" + ); + } + else + { + __asm__ __volatile__ ( + "in __tmp_reg__,__SREG__" "\n\t" + "cli" "\n\t" + "wdr" "\n\t" + "sts %0, %1" "\n\t" + "out __SREG__,__tmp_reg__" "\n\t" + "sts %0, %2" "\n\t" + : /* no outputs */ + : "n" (_SFR_MEM_ADDR(_WD_CONTROL_REG)), + "r" ((uint8_t)(_BV(_WD_CHANGE_BIT) | _BV(WDE))), + "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | + _BV(WDIF) | _BV(WDIE) | _BV(WDE) | (value & 0x07)) ) + : "r0" + ); + } +} + +/*-----------------------------------------------------------*/ + +/* + * Macro to save all the general purpose registers, the save the stack pointer + * into the TCB. + * + * The first thing we do is save the flags then disable interrupts. This is to + * guard our stack against having a context switch interrupt after we have already + * pushed the registers onto the stack - causing the 32 registers to be on the + * stack twice. + * + * r1 is set to zero (__zero_reg__) as the compiler expects it to be thus, however + * some of the math routines make use of R1. + * + * r0 is set to __tmp_reg__ as the compiler expects it to be thus. + * + * #if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) + * #define __RAMPZ__ 0x3B + * #define __EIND__ 0x3C + * #endif + * + * The interrupts will have been disabled during the call to portSAVE_CONTEXT() + * so we need not worry about reading/writing to the stack pointer. + */ +#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +/* 3-Byte PC Save */ +#define portSAVE_CONTEXT() \ + __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SREG__ \n\t" \ + "cli \n\t" \ + "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, 0x3B \n\t" \ + "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, 0x3C \n\t" \ + "push __tmp_reg__ \n\t" \ + "push __zero_reg__ \n\t" \ + "clr __zero_reg__ \n\t" \ + "push r2 \n\t" \ + "push r3 \n\t" \ + "push r4 \n\t" \ + "push r5 \n\t" \ + "push r6 \n\t" \ + "push r7 \n\t" \ + "push r8 \n\t" \ + "push r9 \n\t" \ + "push r10 \n\t" \ + "push r11 \n\t" \ + "push r12 \n\t" \ + "push r13 \n\t" \ + "push r14 \n\t" \ + "push r15 \n\t" \ + "push r16 \n\t" \ + "push r17 \n\t" \ + "push r18 \n\t" \ + "push r19 \n\t" \ + "push r20 \n\t" \ + "push r21 \n\t" \ + "push r22 \n\t" \ + "push r23 \n\t" \ + "push r24 \n\t" \ + "push r25 \n\t" \ + "push r26 \n\t" \ + "push r27 \n\t" \ + "push r28 \n\t" \ + "push r29 \n\t" \ + "push r30 \n\t" \ + "push r31 \n\t" \ + "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "in __tmp_reg__, __SP_L__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SP_H__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + ); +#else +/* 2-Byte PC Save */ +#define portSAVE_CONTEXT() \ + __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SREG__ \n\t" \ + "cli \n\t" \ + "push __tmp_reg__ \n\t" \ + "push __zero_reg__ \n\t" \ + "clr __zero_reg__ \n\t" \ + "push r2 \n\t" \ + "push r3 \n\t" \ + "push r4 \n\t" \ + "push r5 \n\t" \ + "push r6 \n\t" \ + "push r7 \n\t" \ + "push r8 \n\t" \ + "push r9 \n\t" \ + "push r10 \n\t" \ + "push r11 \n\t" \ + "push r12 \n\t" \ + "push r13 \n\t" \ + "push r14 \n\t" \ + "push r15 \n\t" \ + "push r16 \n\t" \ + "push r17 \n\t" \ + "push r18 \n\t" \ + "push r19 \n\t" \ + "push r20 \n\t" \ + "push r21 \n\t" \ + "push r22 \n\t" \ + "push r23 \n\t" \ + "push r24 \n\t" \ + "push r25 \n\t" \ + "push r26 \n\t" \ + "push r27 \n\t" \ + "push r28 \n\t" \ + "push r29 \n\t" \ + "push r30 \n\t" \ + "push r31 \n\t" \ + "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "in __tmp_reg__, __SP_L__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SP_H__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + ); +#endif + +/* + * Opposite to portSAVE_CONTEXT(). Interrupts will have been disabled during + * the context save so we can write to the stack pointer. + */ +#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +/* 3-Byte PC Restore */ +#define portRESTORE_CONTEXT() \ + __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "ld r28, x+ \n\t" \ + "out __SP_L__, r28 \n\t" \ + "ld r29, x+ \n\t" \ + "out __SP_H__, r29 \n\t" \ + "pop r31 \n\t" \ + "pop r30 \n\t" \ + "pop r29 \n\t" \ + "pop r28 \n\t" \ + "pop r27 \n\t" \ + "pop r26 \n\t" \ + "pop r25 \n\t" \ + "pop r24 \n\t" \ + "pop r23 \n\t" \ + "pop r22 \n\t" \ + "pop r21 \n\t" \ + "pop r20 \n\t" \ + "pop r19 \n\t" \ + "pop r18 \n\t" \ + "pop r17 \n\t" \ + "pop r16 \n\t" \ + "pop r15 \n\t" \ + "pop r14 \n\t" \ + "pop r13 \n\t" \ + "pop r12 \n\t" \ + "pop r11 \n\t" \ + "pop r10 \n\t" \ + "pop r9 \n\t" \ + "pop r8 \n\t" \ + "pop r7 \n\t" \ + "pop r6 \n\t" \ + "pop r5 \n\t" \ + "pop r4 \n\t" \ + "pop r3 \n\t" \ + "pop r2 \n\t" \ + "pop __zero_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out 0x3C, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out 0x3B, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out __SREG__, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + ); +#else +/* 2-Byte PC Restore */ +#define portRESTORE_CONTEXT() \ + __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "ld r28, x+ \n\t" \ + "out __SP_L__, r28 \n\t" \ + "ld r29, x+ \n\t" \ + "out __SP_H__, r29 \n\t" \ + "pop r31 \n\t" \ + "pop r30 \n\t" \ + "pop r29 \n\t" \ + "pop r28 \n\t" \ + "pop r27 \n\t" \ + "pop r26 \n\t" \ + "pop r25 \n\t" \ + "pop r24 \n\t" \ + "pop r23 \n\t" \ + "pop r22 \n\t" \ + "pop r21 \n\t" \ + "pop r20 \n\t" \ + "pop r19 \n\t" \ + "pop r18 \n\t" \ + "pop r17 \n\t" \ + "pop r16 \n\t" \ + "pop r15 \n\t" \ + "pop r14 \n\t" \ + "pop r13 \n\t" \ + "pop r12 \n\t" \ + "pop r11 \n\t" \ + "pop r10 \n\t" \ + "pop r9 \n\t" \ + "pop r8 \n\t" \ + "pop r7 \n\t" \ + "pop r6 \n\t" \ + "pop r5 \n\t" \ + "pop r4 \n\t" \ + "pop r3 \n\t" \ + "pop r2 \n\t" \ + "pop __zero_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out __SREG__, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + ); +#endif +/*-----------------------------------------------------------*/ + + +/* + * See header file for description. + */ +StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) +{ +uint16_t usAddress; + + /* Place a few bytes of known values on the bottom of the stack. + This is just useful for debugging. */ + + *pxTopOfStack = 0x11; + pxTopOfStack--; + *pxTopOfStack = 0x22; + pxTopOfStack--; + *pxTopOfStack = 0x33; + pxTopOfStack--; + + /* Simulate how the stack would look after a call to vPortYield() generated by + the compiler. */ + + /* The start of the task code will be popped off the stack last, so place + it on first. */ + +#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) + /* The AVR ATmega2560/ATmega2561 have 256KBytes of program memory and a 17-bit + * program counter. When a code address is stored on the stack, it takes 3 bytes + * instead of 2 for the other ATmega* chips. + * + * Store 0 as the top byte since we force all task routines to the bottom 128K + * of flash. We do this by using the .lowtext label in the linker script. + * + * In order to do this properly, we would need to get a full 3-byte pointer to + * pxCode. That requires a change to GCC. Not likely to happen any time soon. + */ + usAddress = ( uint16_t ) pxCode; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + usAddress >>= 8; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + *pxTopOfStack = 0; + pxTopOfStack--; +#else + usAddress = ( uint16_t ) pxCode; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + usAddress >>= 8; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; +#endif + + /* Next simulate the stack as if after a call to portSAVE_CONTEXT(). + portSAVE_CONTEXT places the flags on the stack immediately after r0 + to ensure the interrupts get disabled as soon as possible, and so ensuring + the stack use is minimal should a context switch interrupt occur. */ + *pxTopOfStack = ( StackType_t ) 0x00; /* R0 */ + pxTopOfStack--; + *pxTopOfStack = portFLAGS_INT_ENABLED; + pxTopOfStack--; + +#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) + + /* If we have an ATmega256x, we are also saving the RAMPZ and EIND registers. + * We should default those to 0. + */ + *pxTopOfStack = ( StackType_t ) 0x00; /* EIND */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x00; /* RAMPZ */ + pxTopOfStack--; + +#endif + + /* Now the remaining registers. The compiler expects R1 to be 0. */ + *pxTopOfStack = ( StackType_t ) 0x00; /* R1 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x02; /* R2 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x03; /* R3 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x04; /* R4 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x05; /* R5 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x06; /* R6 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x07; /* R7 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x08; /* R8 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x09; /* R9 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x10; /* R10 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x11; /* R11 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x12; /* R12 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x13; /* R13 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x14; /* R14 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x15; /* R15 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x16; /* R16 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x17; /* R17 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x18; /* R18 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x19; /* R19 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x20; /* R20 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x21; /* R21 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x22; /* R22 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x23; /* R23 */ + pxTopOfStack--; + + /* Place the parameter on the stack in the expected location. */ + usAddress = ( uint16_t ) pvParameters; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + usAddress >>= 8; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + *pxTopOfStack = ( StackType_t ) 0x26; /* R26 X */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x27; /* R27 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x28; /* R28 Y */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x29; /* R29 */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x30; /* R30 Z */ + pxTopOfStack--; + *pxTopOfStack = ( StackType_t ) 0x031; /* R31 */ + pxTopOfStack--; + + return pxTopOfStack; +} +/*-----------------------------------------------------------*/ + +BaseType_t xPortStartScheduler( void ) +{ + /* Setup the relevant timer hardware to generate the tick. */ + prvSetupTimerInterrupt(); + + /* Restore the context of the first task that is going to run. */ + portRESTORE_CONTEXT(); + + /* Simulate a function call end as generated by the compiler. We will now + jump to the start of the task the context of which we have just restored. */ + __asm__ __volatile__ ( "ret" ); + + /* Should not get here. */ + return pdTRUE; +} +/*-----------------------------------------------------------*/ + +void vPortEndScheduler( void ) +{ + /* It is unlikely that the AVR port will get stopped. If required simply + disable the tick interrupt here. */ + +#if defined (portUSE_WDTO) + wdt_disable(); // disable Watchdog Timer + +#elif defined( portUSE_TIMER0 ) + portTIMSK &= ~( _BV(OCIE0B)|_BV(OCIE0A)|_BV(TOIE0) ); // disable all Timer0 interrupts + +#endif +} +/*-----------------------------------------------------------*/ + +/* + * Manual context switch. The first thing we do is save the registers so we + * can use a naked attribute. + */ +void vPortYield( void ) __attribute__ ( ( hot, flatten, naked ) ); +void vPortYield( void ) +{ + portSAVE_CONTEXT(); + vTaskSwitchContext(); + portRESTORE_CONTEXT(); + + __asm__ __volatile__ ( "ret" ); +} +/*-----------------------------------------------------------*/ + +/* + * Context switch function used by the tick. This must be identical to + * vPortYield() from the call to vTaskSwitchContext() onwards. The only + * difference from vPortYield() is the tick count is incremented as the + * call comes from the tick ISR. + */ +void vPortYieldFromTick( void ) __attribute__ ( ( hot, flatten, naked ) ); +void vPortYieldFromTick( void ) +{ + portSAVE_CONTEXT(); + if( xTaskIncrementTick() != pdFALSE ) + { + vTaskSwitchContext(); + } + portRESTORE_CONTEXT(); + + __asm__ __volatile__ ( "ret" ); +} +/*-----------------------------------------------------------*/ + +#if defined(portUSE_WDTO) +/* + * Setup WDT to generate a tick interrupt. + */ +void prvSetupTimerInterrupt( void ) +{ + //reset watchdog + wdt_reset(); + + /* actual port tick rate in Hz, calculated */ + portTickRateHz = configTICK_RATE_HZ; + /* initialise first second of ticks */ + ticksRemainingInSec = portTickRateHz; + + //set up WDT Interrupt (rather than the WDT Reset). + wdt_interrupt_enable( portUSE_WDTO ); +} + +#elif defined (portUSE_TIMER0) +/* + * Setup Timer0 compare match A to generate a tick interrupt. + */ +static void prvSetupTimerInterrupt( void ) +{ +uint32_t ulCompareMatch; +uint8_t ucLowByte; + + /* Using 8bit Timer0 to generate the tick. Correct fuses must be + selected for the configCPU_CLOCK_HZ clock.*/ + + ulCompareMatch = configCPU_CLOCK_HZ / configTICK_RATE_HZ; + + /* We only have 8 bits so have to scale 1024 to get our required tick rate. */ + ulCompareMatch /= portCLOCK_PRESCALER; + + /* actual port tick rate in Hz, calculated */ + portTickRateHz = (TickType_t) ((uint32_t) configCPU_CLOCK_HZ / ( portCLOCK_PRESCALER * ulCompareMatch )); + /* initialise first second of ticks */ + ticksRemainingInSec = portTickRateHz; + + /* Adjust for correct value. */ + ulCompareMatch -= ( uint32_t ) 1; + + /* Setup compare match value for compare match A. Interrupts are disabled + before this is called so we need not worry here. */ + ucLowByte = ( uint8_t ) ( ulCompareMatch & ( uint32_t ) 0xff ); + portOCRL = ucLowByte; + + /* Setup clock source and compare match behaviour. */ + portTCCRa = portCLEAR_COUNTER_ON_MATCH; + portTCCRb = portPRESCALE_1024; + + + /* Enable the interrupt - this is okay as interrupt are currently globally disabled. */ + ucLowByte = portTIMSK; + ucLowByte |= portCOMPARE_MATCH_A_INTERRUPT_ENABLE; + portTIMSK = ucLowByte; + +} + +#endif + +/*-----------------------------------------------------------*/ + +#if configUSE_PREEMPTION == 1 + + /* + * Tick ISR for preemptive scheduler. We can use a naked attribute as + * the context is saved at the start of vPortYieldFromTick(). The tick + * count is incremented after the context is saved. + * + * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. + * + */ + ISR(portSCHEDULER_ISR, ISR_NAKED) __attribute__ ((hot, flatten)); +// ISR(portSCHEDULER_ISR, ISR_NAKED ISR_NOBLOCK) __attribute__ ((hot, flatten)); + + ISR(portSCHEDULER_ISR) + { + vPortYieldFromTick(); + __asm__ __volatile__ ( "reti" ); + } +#else + + /* + * Tick ISR for the cooperative scheduler. All this does is increment the + * tick count. We don't need to switch context, this can only be done by + * manual calls to taskYIELD(); + * + * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. + */ + ISR(portSCHEDULER_ISR) __attribute__ ((hot, flatten)); +// ISR(portSCHEDULER_ISR, ISR_NOBLOCK) __attribute__ ((hot, flatten)); + + ISR(portSCHEDULER_ISR) + { + xTaskIncrementTick(); + } +#endif + + diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h new file mode 100644 index 0000000000..ccf2a2b1e4 --- /dev/null +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -0,0 +1,139 @@ +/* + * FreeRTOS Kernel V10.3.1 + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * http://www.FreeRTOS.org + * http://aws.amazon.com/freertos + * + * 1 tab == 4 spaces! +*/ + +#ifndef PORTMACRO_H +#define PORTMACRO_H + +#ifdef __cplusplus +extern "C" { +#endif + +/*----------------------------------------------------------- + * Port specific definitions. + * + * The settings in this file configure FreeRTOS correctly for the + * given hardware and compiler. + * + * These settings should not be altered. + *----------------------------------------------------------- + */ + +/* Type definitions. */ + +typedef uint8_t StackType_t; +typedef int8_t BaseType_t; +typedef uint8_t UBaseType_t; + +#if configUSE_16_BIT_TICKS == 1 + typedef uint16_t TickType_t; + #define portMAX_DELAY ( TickType_t ) 0xffff +#else + typedef uint32_t TickType_t; + #define portMAX_DELAY ( TickType_t ) 0xffffffffUL +#endif +/*-----------------------------------------------------------*/ + +/* Critical section management. */ + +#define portENTER_CRITICAL() __asm__ __volatile__ ( \ + "in __tmp_reg__, __SREG__" "\n\t" \ + "cli" "\n\t" \ + "push __tmp_reg__" "\n\t" \ + ::: "memory" \ + ) + + +#define portEXIT_CRITICAL() __asm__ __volatile__ ( \ + "pop __tmp_reg__" "\n\t" \ + "out __SREG__, __tmp_reg__" "\n\t" \ + ::: "memory" \ + ) + + +#define portDISABLE_INTERRUPTS() __asm__ __volatile__ ( "cli" ::: "memory") +#define portENABLE_INTERRUPTS() __asm__ __volatile__ ( "sei" ::: "memory") + +/*-----------------------------------------------------------*/ + +/* Architecture specifics. */ + +// System Tick - Scheduler timer +// Prefer to use the Watchdog timer, but also Timer 0 is ok. + +#define portUSE_WDTO WDTO_15MS // portUSE_WDTO to use the Watchdog Timer for xTaskIncrementTick + +/* Watchdog period options: WDTO_15MS + WDTO_30MS + WDTO_60MS + WDTO_120MS + WDTO_250MS + WDTO_500MS + +*/ + +#if !defined( portUSE_WDTO ) +#define portUSE_TIMER0 // portUSE_TIMER0 to use 8 bit Timer0 for xTaskIncrementTick +#endif + +#define portSTACK_GROWTH ( -1 ) + +/* Timing for the scheduler. + * Watchdog Timer is 128kHz nominal, + * but 120 kHz at 5V DC and 25 degrees is actually more accurate, + * from data sheet. + */ +#if defined( portUSE_WDTO ) +#define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) // Inaccurately assuming 128 kHz Watchdog Timer. +#else +#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) +#endif + +#define portBYTE_ALIGNMENT 1 +#define portNOP() __asm__ __volatile__ ( "nop" ); +/*-----------------------------------------------------------*/ + +/* Kernel utilities. */ +extern void vPortYield( void ) __attribute__ ( ( naked ) ); +#define portYIELD() vPortYield() +/*-----------------------------------------------------------*/ + +#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +/* Task function macros as described on the FreeRTOS.org WEB site. */ +// Add .lowtext tag for the linker for ATmega2560 and ATmega2561. To make sure they are loaded in low memory. +#define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) __attribute__ ((section (".lowtext"))) +#else +#define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) +#endif + +#define portTASK_FUNCTION( vFunction, pvParameters ) void vFunction( void *pvParameters ) + +#ifdef __cplusplus +} +#endif + +#endif /* PORTMACRO_H */ + From 58c58af7045c71365388c7f7c66792e655627735 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Thu, 9 Apr 2020 08:56:57 +1000 Subject: [PATCH 02/24] Create a readme.md --- portable/GCC/ATmegaxxxx/readme.md | 62 +++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 portable/GCC/ATmegaxxxx/readme.md diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md new file mode 100644 index 0000000000..c14f7c051c --- /dev/null +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -0,0 +1,62 @@ +

ATmegaxxxx

+ +__Port for generalised Microchip ATmega architecture__ + +

Description

+ +This port provides a basis for supporting all modern ATmega devices using either the Enhanced Watchdog Timer, or Timer0 (an 8-bit Timer generally available across the whole range). + +This initial commit contains the information required to build with System Tick being generated by either the: +- Watchdog Timer, or +- Timer 0 - an 8-bit Timer + +Further commits can add support for 16-bit Timers available on many relevant devices. The availability of these 16-bit Timers is somewhat device specific, and these complex and highly configurable Timers are often used to generate phase correct PWM timing (for example) and they would be wasted as a simple System Tick. + +The port also provides support for the 3 byte program counter devices __ATmega2560__ and __ATmega2561__. Specific to these two devices the `RAMPZ` and `EIND` registers need to be preserved during a context switch. Also, due to a limitation in GCC, the scheduler needs to reside in the lower 128kB of flash for both of these devices. This is achieved by adding the `.lowtext` section attribute to the function prototype. + +To build generic Microchip (AVR) ATmega support the similarities across the family must be considered, and differences respected. Some comments on the strategy follow. + +

System Tick

+ +The Microchip (AVR) ATmega family has limited Timer and Pin capabilities, and is designed to be used in physical applications, controlling hardware with PWM and recognising level and edge voltage changes. It does this mainly through the use of 16-bit Timers (for generating phase correct PWM by up/down counting), and Pins attached to Interrupts. The 8-bit Timers are also attached to Pins, and they can be used for more simple timing tasks, requiring only a single counting direction. + +The Timers not attached to Pins (and therefore not impacting the application of the device) are an additional 16-bit Timer (very device dependent, eg Timer3 on 1284p), and the Watch Dog Timer. + +The Watch Dog Timer is configured identically across the entire range of ATmega devices. It comes in two variants. 1. Old style (eg ATmega32) which does not have an Interrupt capability, and hence on these old devices cannot be used as the System Tick. and 2. New style enhanced WDT, which can generate an Interrupt, and is available on every relevant device. + +Using the Watch Dog Timer (WDT) to generate the System Tick does not impact its use as a watch dog. It can be configured to generate a System Tick interrupt, and then one period later to Reset the device if the interrupt is not serviced. + +Configuration and usage of the WDT is covered in `` which was revised in avr-libc 2.0.0. + +Two additional WDT functions are provided in `port.c`, which extend avr-libc functions to enable the WDT Interrupt without enabling Reset `wdt_interrupt_enable()`, and to enable both the Interrupt and the Reset `wdt_interrupt_reset_enable()`. + +

3 Byte PC Devices

+ +The ATtiny, ATmega, ATxmega families can optionally support both 3 byte PC and 3 byte RAM addresses. However, focusing on just the ATmega family only two devices have a large Flash requiring them to use 3 byte PC. These are the __ATmega2560__ and __ATmega2561__. This PR provides support for these two devices in two ways. + + - providing `portSAVE_CONTEXT()` and `portRESTORE_CONTEXT` saving both the __RAMPZ__ and __EIND__ registers. + - providing a `portTASK_FUNCTION_PROTO()` with the linker attribute `.lowtext` which is used to ensure that the scheduler and relevant functions remain in the lower 128kB of Flash. + +

Interrupt Nesting

+ +The ATmega family does not support interrupt nesting, having only one interrupt priority. This means that when the Scheduler is running, interrupts are normally disabled. + +When a very time critical process is running, based on microsecond timing generated by one of the Timers, it is important to re-enable interrupts as early as possible in processing a Yield. Fortunately, this is supported through the use of the `NO_BLOCK` decorator when defining the Interrupt Service Routine. + +The `NO_BLOCK` decorator will enable the global interrupt early in the handling of an ISR (in this case for the Scheduler), and enable interrupts to be nested. Using this method, I've been able to successfully implement an [Audio Synthesiser](https://feilipu.me/2015/06/02/goldilocks-analogue-synthesizer/) with less than 83 microseconds for each cycle, whilst still running the Scheduler to handle display and input. + +Using `NO_BLOCK` is optional, and should only be done if a critical Timer should interrupt the Scheduler. + +

Heap Management

+ +Most users of FreeRTOS will choose to manage their own heap using one of the pre-allocated heap management algorithms, but for those that choose to use `heap_3.c`, the wrappered `malloc()` method, there is an issue that needs to be addressed. + +The avr-libc library assumes that the stack will always be above the heap, and does a check for this when responding to a `malloc()` request. This is not the case when Tasks are running, as their stack is located in the early allocated heap address ranges which will be below free heap memory, and so the `malloc()` request will fail even though heap space is available. + +To avoid this issue causing `pvPort_Malloc()` to failing, the user needs to issue this tuning statement BEFORE they use the heap, or use the `xTaskCreate()` API. + +```c +if( __malloc_heap_end == 0 ) + __malloc_heap_end = (char *)(RAMEND - __malloc_margin); +``` +Unfortunately in the repository there is nowhere sensible to include this statement. From d62af1e8a325899698ec300f5cf5cf0c4e264f32 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Thu, 9 Apr 2020 08:58:42 +1000 Subject: [PATCH 03/24] Update readme.md --- portable/GCC/ATmegaxxxx/readme.md | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index c14f7c051c..4ce7090b4c 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -60,3 +60,21 @@ if( __malloc_heap_end == 0 ) __malloc_heap_end = (char *)(RAMEND - __malloc_margin); ``` Unfortunately in the repository there is nowhere sensible to include this statement. + +

Supported Devices

+ +ATmega devices without enhanced __WDT__ Interrupt capability - use Timer0. + + - ATmega8A/16A/32A/64A/128A -> 4kB RAM + - ATmega808/809/1608/1609/3208/3209/4808/4809 -> 6kB RAM + - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM + - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM + +ATmega devices with __ENHANCED WDT__ Interrupt capability - use WDT. + + - ATmega8U2/16U2/32U2 -> 2kB RAM + - ATmega16U4/32U4 - Arduino Leonardo -> 2.5kB RAM + - ATmega48PB/88PB/168PB/328PB - Arduino Uno -> 2kB RAM + - ATmega164PA/324PA/644PA/1284P - Goldilocks -> __16kB RAM__ + - ATmega324PB -> 2kB RAM + - ATmega640/1280/2560/1281/2561 - Arduino Mega -> __8kB RAM + XRAM__ From d356bfc02fc07adbfb7124e84ef0fa380d9d89cb Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Thu, 9 Apr 2020 17:28:22 +1000 Subject: [PATCH 04/24] atmega - add legacy type definitions --- portable/GCC/ATmegaxxxx/portmacro.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index ccf2a2b1e4..80fbbd3fd0 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -43,6 +43,11 @@ extern "C" { */ /* Type definitions. */ +#define portCHAR char +#define portFLOAT float +#define portDOUBLE double +#define portLONG long +#define portSHORT int typedef uint8_t StackType_t; typedef int8_t BaseType_t; From 3ece178dd0f19fd6bc05c77a383a620b0645fac6 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Fri, 10 Apr 2020 14:39:14 +1000 Subject: [PATCH 05/24] ATmegaxxxx - refine WDT config --- portable/GCC/ATmegaxxxx/port.c | 10 ++++- portable/GCC/ATmegaxxxx/portmacro.h | 61 ++++++++++++++++------------- 2 files changed, 41 insertions(+), 30 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index fe1709788a..1373970fcd 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -38,11 +38,11 @@ *----------------------------------------------------------*/ /* Start tasks with interrupts enabled. */ -#define portFLAGS_INT_ENABLED ( (StackType_t) 0x80 ) +#define portFLAGS_INT_ENABLED ( (StackType_t) 0x80 ) #if defined( portUSE_WDTO) #warning "Watchdog Timer used for scheduler." - #define portSCHEDULER_ISR WDT_vect + #define portSCHEDULER_ISR WDT_vect #elif defined( portUSE_TIMER0 ) /* Hardware constants for Timer0. */ @@ -97,6 +97,8 @@ static void prvSetupTimerInterrupt( void ); Updated to match avr-libc 2.0.0 */ +#if defined( portUSE_WDTO) + static __inline__ __attribute__ ((__always_inline__)) void wdt_interrupt_enable (const uint8_t value) @@ -136,6 +138,7 @@ void wdt_interrupt_enable (const uint8_t value) ); } } +#endif /*-----------------------------------------------------------*/ /** @@ -160,6 +163,8 @@ void wdt_interrupt_enable (const uint8_t value) Updated to match avr-libc 2.0.0 */ +#if defined( portUSE_WDTO) + static __inline__ __attribute__ ((__always_inline__)) void wdt_interrupt_reset_enable (const uint8_t value) @@ -199,6 +204,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) ); } } +#endif /*-----------------------------------------------------------*/ diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index 80fbbd3fd0..ae6ce20cd2 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -43,11 +43,11 @@ extern "C" { */ /* Type definitions. */ -#define portCHAR char -#define portFLOAT float -#define portDOUBLE double -#define portLONG long -#define portSHORT int +#define portCHAR char +#define portFLOAT float +#define portDOUBLE double +#define portLONG long +#define portSHORT int typedef uint8_t StackType_t; typedef int8_t BaseType_t; @@ -55,16 +55,16 @@ typedef uint8_t UBaseType_t; #if configUSE_16_BIT_TICKS == 1 typedef uint16_t TickType_t; - #define portMAX_DELAY ( TickType_t ) 0xffff + #define portMAX_DELAY ( TickType_t ) 0xffff #else typedef uint32_t TickType_t; - #define portMAX_DELAY ( TickType_t ) 0xffffffffUL + #define portMAX_DELAY ( TickType_t ) 0xffffffffUL #endif /*-----------------------------------------------------------*/ /* Critical section management. */ -#define portENTER_CRITICAL() __asm__ __volatile__ ( \ +#define portENTER_CRITICAL() __asm__ __volatile__ ( \ "in __tmp_reg__, __SREG__" "\n\t" \ "cli" "\n\t" \ "push __tmp_reg__" "\n\t" \ @@ -72,39 +72,44 @@ typedef uint8_t UBaseType_t; ) -#define portEXIT_CRITICAL() __asm__ __volatile__ ( \ +#define portEXIT_CRITICAL() __asm__ __volatile__ ( \ "pop __tmp_reg__" "\n\t" \ "out __SREG__, __tmp_reg__" "\n\t" \ ::: "memory" \ ) -#define portDISABLE_INTERRUPTS() __asm__ __volatile__ ( "cli" ::: "memory") -#define portENABLE_INTERRUPTS() __asm__ __volatile__ ( "sei" ::: "memory") +#define portDISABLE_INTERRUPTS() __asm__ __volatile__ ( "cli" ::: "memory") +#define portENABLE_INTERRUPTS() __asm__ __volatile__ ( "sei" ::: "memory") /*-----------------------------------------------------------*/ /* Architecture specifics. */ // System Tick - Scheduler timer -// Prefer to use the Watchdog timer, but also Timer 0 is ok. +// Prefer to use the enhanced Watchdog Timer, but also Timer0 is ok. -#define portUSE_WDTO WDTO_15MS // portUSE_WDTO to use the Watchdog Timer for xTaskIncrementTick +#if defined(WDIE) && defined(WDIF) // Enhanced WDT with interrupt capability -/* Watchdog period options: WDTO_15MS - WDTO_30MS - WDTO_60MS - WDTO_120MS - WDTO_250MS - WDTO_500MS +#define portUSE_WDTO WDTO_15MS // portUSE_WDTO to use the Watchdog Timer for xTaskIncrementTick +/* Watchdog period options: WDTO_15MS + WDTO_30MS + WDTO_60MS + WDTO_120MS + WDTO_250MS + WDTO_500MS + WDTO_1S + WDTO_2S */ -#if !defined( portUSE_WDTO ) +#else + #define portUSE_TIMER0 // portUSE_TIMER0 to use 8 bit Timer0 for xTaskIncrementTick + #endif -#define portSTACK_GROWTH ( -1 ) +#define portSTACK_GROWTH ( -1 ) /* Timing for the scheduler. * Watchdog Timer is 128kHz nominal, @@ -112,23 +117,23 @@ typedef uint8_t UBaseType_t; * from data sheet. */ #if defined( portUSE_WDTO ) -#define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) // Inaccurately assuming 128 kHz Watchdog Timer. +#define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) // Inaccurately assuming 128 kHz Watchdog Timer. #else -#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) +#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) #endif -#define portBYTE_ALIGNMENT 1 -#define portNOP() __asm__ __volatile__ ( "nop" ); +#define portBYTE_ALIGNMENT 1 +#define portNOP() __asm__ __volatile__ ( "nop" ); /*-----------------------------------------------------------*/ /* Kernel utilities. */ -extern void vPortYield( void ) __attribute__ ( ( naked ) ); -#define portYIELD() vPortYield() +extern void vPortYield( void ) __attribute__ ( ( naked ) ); +#define portYIELD() vPortYield() /*-----------------------------------------------------------*/ #if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) /* Task function macros as described on the FreeRTOS.org WEB site. */ -// Add .lowtext tag for the linker for ATmega2560 and ATmega2561. To make sure they are loaded in low memory. +// Add .lowtext tag from the linker script avr6.x for ATmega2560 and ATmega2561. To make sure they are loaded in low memory. #define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) __attribute__ ((section (".lowtext"))) #else #define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) From 5e32393035673df27df43a04d3d04c3705c4fb04 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 11:31:24 +1000 Subject: [PATCH 06/24] ATmegaxxxx - remove single line comments --- portable/GCC/ATmegaxxxx/port.c | 12 ++++++------ portable/GCC/ATmegaxxxx/portmacro.h | 28 ++++++++++++++++------------ portable/GCC/ATmegaxxxx/readme.md | 20 ++++++++++---------- 3 files changed, 32 insertions(+), 28 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 1373970fcd..370a9b9aa7 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -600,10 +600,10 @@ void vPortEndScheduler( void ) disable the tick interrupt here. */ #if defined (portUSE_WDTO) - wdt_disable(); // disable Watchdog Timer + wdt_disable(); /* disable Watchdog Timer */ #elif defined( portUSE_TIMER0 ) - portTIMSK &= ~( _BV(OCIE0B)|_BV(OCIE0A)|_BV(TOIE0) ); // disable all Timer0 interrupts + portTIMSK &= ~( _BV(OCIE0B)|_BV(OCIE0A)|_BV(TOIE0) ); /* disable all Timer0 interrupts */ #endif } @@ -650,7 +650,7 @@ void vPortYieldFromTick( void ) */ void prvSetupTimerInterrupt( void ) { - //reset watchdog + /* reset watchdog */ wdt_reset(); /* actual port tick rate in Hz, calculated */ @@ -658,7 +658,7 @@ void prvSetupTimerInterrupt( void ) /* initialise first second of ticks */ ticksRemainingInSec = portTickRateHz; - //set up WDT Interrupt (rather than the WDT Reset). + /* set up WDT Interrupt (rather than the WDT Reset). */ wdt_interrupt_enable( portUSE_WDTO ); } @@ -719,7 +719,7 @@ uint8_t ucLowByte; * */ ISR(portSCHEDULER_ISR, ISR_NAKED) __attribute__ ((hot, flatten)); -// ISR(portSCHEDULER_ISR, ISR_NAKED ISR_NOBLOCK) __attribute__ ((hot, flatten)); +/* ISR(portSCHEDULER_ISR, ISR_NAKED ISR_NOBLOCK) __attribute__ ((hot, flatten)); */ ISR(portSCHEDULER_ISR) { @@ -736,7 +736,7 @@ uint8_t ucLowByte; * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. */ ISR(portSCHEDULER_ISR) __attribute__ ((hot, flatten)); -// ISR(portSCHEDULER_ISR, ISR_NOBLOCK) __attribute__ ((hot, flatten)); +/* ISR(portSCHEDULER_ISR, ISR_NOBLOCK) __attribute__ ((hot, flatten)); */ ISR(portSCHEDULER_ISR) { diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index ae6ce20cd2..492bf85623 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -49,15 +49,15 @@ extern "C" { #define portLONG long #define portSHORT int -typedef uint8_t StackType_t; -typedef int8_t BaseType_t; -typedef uint8_t UBaseType_t; +typedef uint8_t StackType_t; +typedef int8_t BaseType_t; +typedef uint8_t UBaseType_t; #if configUSE_16_BIT_TICKS == 1 - typedef uint16_t TickType_t; + typedef uint16_t TickType_t; #define portMAX_DELAY ( TickType_t ) 0xffff #else - typedef uint32_t TickType_t; + typedef uint32_t TickType_t; #define portMAX_DELAY ( TickType_t ) 0xffffffffUL #endif /*-----------------------------------------------------------*/ @@ -86,12 +86,13 @@ typedef uint8_t UBaseType_t; /* Architecture specifics. */ -// System Tick - Scheduler timer -// Prefer to use the enhanced Watchdog Timer, but also Timer0 is ok. +/* System Tick - Scheduler timer + * Prefer to use the enhanced Watchdog Timer, but also Timer0 is ok. + */ -#if defined(WDIE) && defined(WDIF) // Enhanced WDT with interrupt capability +#if defined(WDIE) && defined(WDIF) /* If Enhanced WDT with interrupt capability is available */ -#define portUSE_WDTO WDTO_15MS // portUSE_WDTO to use the Watchdog Timer for xTaskIncrementTick +#define portUSE_WDTO WDTO_15MS /* use the Watchdog Timer for xTaskIncrementTick */ /* Watchdog period options: WDTO_15MS WDTO_30MS @@ -105,7 +106,7 @@ typedef uint8_t UBaseType_t; #else -#define portUSE_TIMER0 // portUSE_TIMER0 to use 8 bit Timer0 for xTaskIncrementTick +#define portUSE_TIMER0 /* use the 8-bit Timer0 for xTaskIncrementTick */ #endif @@ -117,7 +118,7 @@ typedef uint8_t UBaseType_t; * from data sheet. */ #if defined( portUSE_WDTO ) -#define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) // Inaccurately assuming 128 kHz Watchdog Timer. +#define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) #else #define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) #endif @@ -133,7 +134,10 @@ extern void vPortYield( void ) __attribute__ ( ( naked ) ); #if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) /* Task function macros as described on the FreeRTOS.org WEB site. */ -// Add .lowtext tag from the linker script avr6.x for ATmega2560 and ATmega2561. To make sure they are loaded in low memory. + +/* Add .lowtext tag from the avr linker script avr6.x for ATmega2560 and ATmega2561 + * to make sure functions are loaded in low memory. + */ #define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) __attribute__ ((section (".lowtext"))) #else #define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 4ce7090b4c..1d502e890e 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -8,7 +8,7 @@ This port provides a basis for supporting all modern ATmega devices using either This initial commit contains the information required to build with System Tick being generated by either the: - Watchdog Timer, or -- Timer 0 - an 8-bit Timer +- Timer0 - an 8-bit Timer Further commits can add support for 16-bit Timers available on many relevant devices. The availability of these 16-bit Timers is somewhat device specific, and these complex and highly configurable Timers are often used to generate phase correct PWM timing (for example) and they would be wasted as a simple System Tick. @@ -59,18 +59,11 @@ To avoid this issue causing `pvPort_Malloc()` to failing, the user needs to issu if( __malloc_heap_end == 0 ) __malloc_heap_end = (char *)(RAMEND - __malloc_margin); ``` -Unfortunately in the repository there is nowhere sensible to include this statement. +Unfortunately in the repository there is nowhere sensible to include this statement as it should be included early in the `main()` function.

Supported Devices

-ATmega devices without enhanced __WDT__ Interrupt capability - use Timer0. - - - ATmega8A/16A/32A/64A/128A -> 4kB RAM - - ATmega808/809/1608/1609/3208/3209/4808/4809 -> 6kB RAM - - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM - - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM - -ATmega devices with __ENHANCED WDT__ Interrupt capability - use WDT. +ATmega devices with __ENHANCED WDT__ Interrupt capability - will use WDT. - ATmega8U2/16U2/32U2 -> 2kB RAM - ATmega16U4/32U4 - Arduino Leonardo -> 2.5kB RAM @@ -78,3 +71,10 @@ ATmega devices with __ENHANCED WDT__ Interrupt capability - use WDT. - ATmega164PA/324PA/644PA/1284P - Goldilocks -> __16kB RAM__ - ATmega324PB -> 2kB RAM - ATmega640/1280/2560/1281/2561 - Arduino Mega -> __8kB RAM + XRAM__ + +ATmega devices without enhanced __WDT__ Interrupt capability - will use Timer0. + + - ATmega8A/16A/32A/64A/128A -> 4kB RAM + - ATmega808/809/1608/1609/3208/3209/4808/4809 -> 6kB RAM + - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM + - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM From c19e711ba5d4f8ad0c1ed9a54c655b015b1c8e76 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 12:01:44 +1000 Subject: [PATCH 07/24] ATmegaxxxx - discern architecture rather than device --- portable/GCC/ATmegaxxxx/port.c | 10 +++++----- portable/GCC/ATmegaxxxx/portmacro.h | 2 +- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 370a9b9aa7..2a76e98943 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -222,7 +222,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * * r0 is set to __tmp_reg__ as the compiler expects it to be thus. * - * #if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) + * #if defined(__AVR_3_BYTE_PC__) * #define __RAMPZ__ 0x3B * #define __EIND__ 0x3C * #endif @@ -230,7 +230,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * The interrupts will have been disabled during the call to portSAVE_CONTEXT() * so we need not worry about reading/writing to the stack pointer. */ -#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +#if defined(__AVR_3_BYTE_PC__) /* 3-Byte PC Save */ #define portSAVE_CONTEXT() \ __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ @@ -332,7 +332,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * Opposite to portSAVE_CONTEXT(). Interrupts will have been disabled during * the context save so we can write to the stack pointer. */ -#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +#if defined(__AVR_3_BYTE_PC__) /* 3-Byte PC Restore */ #define portRESTORE_CONTEXT() \ __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ @@ -451,7 +451,7 @@ uint16_t usAddress; /* The start of the task code will be popped off the stack last, so place it on first. */ -#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +#if defined(__AVR_3_BYTE_PC__) /* The AVR ATmega2560/ATmega2561 have 256KBytes of program memory and a 17-bit * program counter. When a code address is stored on the stack, it takes 3 bytes * instead of 2 for the other ATmega* chips. @@ -491,7 +491,7 @@ uint16_t usAddress; *pxTopOfStack = portFLAGS_INT_ENABLED; pxTopOfStack--; -#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +#if defined(__AVR_3_BYTE_PC__) /* If we have an ATmega256x, we are also saving the RAMPZ and EIND registers. * We should default those to 0. diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index 492bf85623..253f1379ae 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -132,7 +132,7 @@ extern void vPortYield( void ) __attribute__ ( ( naked ) ); #define portYIELD() vPortYield() /*-----------------------------------------------------------*/ -#if defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) +#if defined(__AVR_3_BYTE_PC__) /* Task function macros as described on the FreeRTOS.org WEB site. */ /* Add .lowtext tag from the avr linker script avr6.x for ATmega2560 and ATmega2561 From 670c00d3a57c81f686c46c4dc7c1d0095cc6f303 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 12:05:39 +1000 Subject: [PATCH 08/24] ATmegaxxxx - remove Timer2 RTC variables --- portable/GCC/ATmegaxxxx/port.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 2a76e98943..0a997c8767 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -67,12 +67,6 @@ any details of its type. */ typedef void TCB_t; extern volatile TCB_t * volatile pxCurrentTCB; -/* actual number of ticks per second, after configuration. */ -TickType_t portTickRateHz; - -/* remaining ticks in each second, decremented to enable the system_tick. */ -volatile TickType_t ticksRemainingInSec; - /*-----------------------------------------------------------*/ /* * Perform hardware setup to enable ticks from timer compare match A. From 520456577a795a5ca565307c6771305fe441dab4 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 12:24:22 +1000 Subject: [PATCH 09/24] ATmegaxxxx - add __AVR_HAVE_RAMPZ__ --- portable/GCC/ATmegaxxxx/port.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 0a997c8767..71c93f9da5 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -216,7 +216,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * * r0 is set to __tmp_reg__ as the compiler expects it to be thus. * - * #if defined(__AVR_3_BYTE_PC__) + * #if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) * #define __RAMPZ__ 0x3B * #define __EIND__ 0x3C * #endif @@ -224,7 +224,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * The interrupts will have been disabled during the call to portSAVE_CONTEXT() * so we need not worry about reading/writing to the stack pointer. */ -#if defined(__AVR_3_BYTE_PC__) +#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) /* 3-Byte PC Save */ #define portSAVE_CONTEXT() \ __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ @@ -326,7 +326,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * Opposite to portSAVE_CONTEXT(). Interrupts will have been disabled during * the context save so we can write to the stack pointer. */ -#if defined(__AVR_3_BYTE_PC__) +#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) /* 3-Byte PC Restore */ #define portRESTORE_CONTEXT() \ __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ @@ -445,7 +445,7 @@ uint16_t usAddress; /* The start of the task code will be popped off the stack last, so place it on first. */ -#if defined(__AVR_3_BYTE_PC__) +#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) /* The AVR ATmega2560/ATmega2561 have 256KBytes of program memory and a 17-bit * program counter. When a code address is stored on the stack, it takes 3 bytes * instead of 2 for the other ATmega* chips. @@ -485,8 +485,7 @@ uint16_t usAddress; *pxTopOfStack = portFLAGS_INT_ENABLED; pxTopOfStack--; -#if defined(__AVR_3_BYTE_PC__) - +#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) /* If we have an ATmega256x, we are also saving the RAMPZ and EIND registers. * We should default those to 0. */ @@ -494,7 +493,6 @@ uint16_t usAddress; pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x00; /* RAMPZ */ pxTopOfStack--; - #endif /* Now the remaining registers. The compiler expects R1 to be 0. */ From 5052273cd782977456a26ccfb03bcfaaed13d1e0 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 12:38:48 +1000 Subject: [PATCH 10/24] ATmegaxxxx - add __AVR_HAVE_RAMPZ__ --- portable/GCC/ATmegaxxxx/port.c | 119 ++++++++++++++++++++++++++++++--- 1 file changed, 111 insertions(+), 8 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 71c93f9da5..3885528b32 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -216,16 +216,19 @@ void wdt_interrupt_reset_enable (const uint8_t value) * * r0 is set to __tmp_reg__ as the compiler expects it to be thus. * - * #if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) - * #define __RAMPZ__ 0x3B + * #if defined(__AVR_3_BYTE_PC__) * #define __EIND__ 0x3C * #endif * + * #if defined(__AVR_HAVE_RAMPZ__) + * #define __RAMPZ__ 0x3B + * #endif + * * The interrupts will have been disabled during the call to portSAVE_CONTEXT() * so we need not worry about reading/writing to the stack pointer. */ #if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) -/* 3-Byte PC Save */ +/* 3-Byte PC Save with RAMPZ */ #define portSAVE_CONTEXT() \ __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ "in __tmp_reg__, __SREG__ \n\t" \ @@ -274,6 +277,54 @@ void wdt_interrupt_reset_enable (const uint8_t value) "in __tmp_reg__, __SP_H__ \n\t" \ "st x+, __tmp_reg__ \n\t" \ ); +#elif defined(__AVR_3_BYTE_PC__) +/* 3-Byte PC Save */ +#define portSAVE_CONTEXT() \ + __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SREG__ \n\t" \ + "cli \n\t" \ + "push __tmp_reg__ \n\t" \ + "in __tmp_reg__, 0x3C \n\t" \ + "push __tmp_reg__ \n\t" \ + "push __zero_reg__ \n\t" \ + "clr __zero_reg__ \n\t" \ + "push r2 \n\t" \ + "push r3 \n\t" \ + "push r4 \n\t" \ + "push r5 \n\t" \ + "push r6 \n\t" \ + "push r7 \n\t" \ + "push r8 \n\t" \ + "push r9 \n\t" \ + "push r10 \n\t" \ + "push r11 \n\t" \ + "push r12 \n\t" \ + "push r13 \n\t" \ + "push r14 \n\t" \ + "push r15 \n\t" \ + "push r16 \n\t" \ + "push r17 \n\t" \ + "push r18 \n\t" \ + "push r19 \n\t" \ + "push r20 \n\t" \ + "push r21 \n\t" \ + "push r22 \n\t" \ + "push r23 \n\t" \ + "push r24 \n\t" \ + "push r25 \n\t" \ + "push r26 \n\t" \ + "push r27 \n\t" \ + "push r28 \n\t" \ + "push r29 \n\t" \ + "push r30 \n\t" \ + "push r31 \n\t" \ + "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "in __tmp_reg__, __SP_L__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + "in __tmp_reg__, __SP_H__ \n\t" \ + "st x+, __tmp_reg__ \n\t" \ + ); #else /* 2-Byte PC Save */ #define portSAVE_CONTEXT() \ @@ -327,7 +378,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * the context save so we can write to the stack pointer. */ #if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) -/* 3-Byte PC Restore */ +/* 3-Byte PC Restore with RAMPZ */ #define portRESTORE_CONTEXT() \ __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ "lds r27, pxCurrentTCB + 1 \n\t" \ @@ -374,6 +425,52 @@ void wdt_interrupt_reset_enable (const uint8_t value) "out __SREG__, __tmp_reg__ \n\t" \ "pop __tmp_reg__ \n\t" \ ); +#elif defined(__AVR_3_BYTE_PC__) +/* 3-Byte PC Restore with RAMPZ */ +#define portRESTORE_CONTEXT() \ + __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ + "lds r27, pxCurrentTCB + 1 \n\t" \ + "ld r28, x+ \n\t" \ + "out __SP_L__, r28 \n\t" \ + "ld r29, x+ \n\t" \ + "out __SP_H__, r29 \n\t" \ + "pop r31 \n\t" \ + "pop r30 \n\t" \ + "pop r29 \n\t" \ + "pop r28 \n\t" \ + "pop r27 \n\t" \ + "pop r26 \n\t" \ + "pop r25 \n\t" \ + "pop r24 \n\t" \ + "pop r23 \n\t" \ + "pop r22 \n\t" \ + "pop r21 \n\t" \ + "pop r20 \n\t" \ + "pop r19 \n\t" \ + "pop r18 \n\t" \ + "pop r17 \n\t" \ + "pop r16 \n\t" \ + "pop r15 \n\t" \ + "pop r14 \n\t" \ + "pop r13 \n\t" \ + "pop r12 \n\t" \ + "pop r11 \n\t" \ + "pop r10 \n\t" \ + "pop r9 \n\t" \ + "pop r8 \n\t" \ + "pop r7 \n\t" \ + "pop r6 \n\t" \ + "pop r5 \n\t" \ + "pop r4 \n\t" \ + "pop r3 \n\t" \ + "pop r2 \n\t" \ + "pop __zero_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out 0x3C, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + "out __SREG__, __tmp_reg__ \n\t" \ + "pop __tmp_reg__ \n\t" \ + ); #else /* 2-Byte PC Restore */ #define portRESTORE_CONTEXT() \ @@ -445,7 +542,7 @@ uint16_t usAddress; /* The start of the task code will be popped off the stack last, so place it on first. */ -#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) +#if defined(__AVR_3_BYTE_PC__) /* The AVR ATmega2560/ATmega2561 have 256KBytes of program memory and a 17-bit * program counter. When a code address is stored on the stack, it takes 3 bytes * instead of 2 for the other ATmega* chips. @@ -485,12 +582,18 @@ uint16_t usAddress; *pxTopOfStack = portFLAGS_INT_ENABLED; pxTopOfStack--; -#if defined(__AVR_3_BYTE_PC__) && defined(__AVR_HAVE_RAMPZ__) - /* If we have an ATmega256x, we are also saving the RAMPZ and EIND registers. - * We should default those to 0. +#if defined(__AVR_3_BYTE_PC__) + /* If we have an ATmega256x, we are also saving the EIND register. + * We should default to 0. */ *pxTopOfStack = ( StackType_t ) 0x00; /* EIND */ pxTopOfStack--; +#endif + +#if defined(__AVR_HAVE_RAMPZ__) + /* If we have an ATmega2560, we are also saving the RAMPZ register. + * We should default to 0. + */ *pxTopOfStack = ( StackType_t ) 0x00; /* RAMPZ */ pxTopOfStack--; #endif From fa8cde691f8dfbbebb415a5cf438996fafac5f24 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 14:20:45 +1000 Subject: [PATCH 11/24] ATmegaxxxx - refine RAMPZ configuration --- portable/GCC/ATmegaxxxx/port.c | 30 +++++++++++++++--------------- portable/GCC/ATmegaxxxx/readme.md | 6 +++++- 2 files changed, 20 insertions(+), 16 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 3885528b32..7889e68b1f 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -216,14 +216,14 @@ void wdt_interrupt_reset_enable (const uint8_t value) * * r0 is set to __tmp_reg__ as the compiler expects it to be thus. * - * #if defined(__AVR_3_BYTE_PC__) - * #define __EIND__ 0x3C - * #endif - * * #if defined(__AVR_HAVE_RAMPZ__) * #define __RAMPZ__ 0x3B * #endif * + * #if defined(__AVR_3_BYTE_PC__) + * #define __EIND__ 0x3C + * #endif + * * The interrupts will have been disabled during the call to portSAVE_CONTEXT() * so we need not worry about reading/writing to the stack pointer. */ @@ -277,14 +277,14 @@ void wdt_interrupt_reset_enable (const uint8_t value) "in __tmp_reg__, __SP_H__ \n\t" \ "st x+, __tmp_reg__ \n\t" \ ); -#elif defined(__AVR_3_BYTE_PC__) -/* 3-Byte PC Save */ +#elif defined(__AVR_HAVE_RAMPZ__) +/* 2-Byte PC Save with RAMPZ */ #define portSAVE_CONTEXT() \ __asm__ __volatile__ ( "push __tmp_reg__ \n\t" \ "in __tmp_reg__, __SREG__ \n\t" \ "cli \n\t" \ "push __tmp_reg__ \n\t" \ - "in __tmp_reg__, 0x3C \n\t" \ + "in __tmp_reg__, 0x3B \n\t" \ "push __tmp_reg__ \n\t" \ "push __zero_reg__ \n\t" \ "clr __zero_reg__ \n\t" \ @@ -425,8 +425,8 @@ void wdt_interrupt_reset_enable (const uint8_t value) "out __SREG__, __tmp_reg__ \n\t" \ "pop __tmp_reg__ \n\t" \ ); -#elif defined(__AVR_3_BYTE_PC__) -/* 3-Byte PC Restore with RAMPZ */ +#elif defined(__AVR_HAVE_RAMPZ__) +/* 2-Byte PC Restore with RAMPZ */ #define portRESTORE_CONTEXT() \ __asm__ __volatile__ ( "lds r26, pxCurrentTCB \n\t" \ "lds r27, pxCurrentTCB + 1 \n\t" \ @@ -466,7 +466,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) "pop r2 \n\t" \ "pop __zero_reg__ \n\t" \ "pop __tmp_reg__ \n\t" \ - "out 0x3C, __tmp_reg__ \n\t" \ + "out 0x3B, __tmp_reg__ \n\t" \ "pop __tmp_reg__ \n\t" \ "out __SREG__, __tmp_reg__ \n\t" \ "pop __tmp_reg__ \n\t" \ @@ -591,7 +591,7 @@ uint16_t usAddress; #endif #if defined(__AVR_HAVE_RAMPZ__) - /* If we have an ATmega2560, we are also saving the RAMPZ register. + /* We are saving the RAMPZ register. * We should default to 0. */ *pxTopOfStack = ( StackType_t ) 0x00; /* RAMPZ */ @@ -814,8 +814,8 @@ uint8_t ucLowByte; * */ ISR(portSCHEDULER_ISR, ISR_NAKED) __attribute__ ((hot, flatten)); -/* ISR(portSCHEDULER_ISR, ISR_NAKED ISR_NOBLOCK) __attribute__ ((hot, flatten)); */ - +/* ISR(portSCHEDULER_ISR, ISR_NAKED ISR_NOBLOCK) __attribute__ ((hot, flatten)); + */ ISR(portSCHEDULER_ISR) { vPortYieldFromTick(); @@ -831,8 +831,8 @@ uint8_t ucLowByte; * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. */ ISR(portSCHEDULER_ISR) __attribute__ ((hot, flatten)); -/* ISR(portSCHEDULER_ISR, ISR_NOBLOCK) __attribute__ ((hot, flatten)); */ - +/* ISR(portSCHEDULER_ISR, ISR_NOBLOCK) __attribute__ ((hot, flatten)); + */ ISR(portSCHEDULER_ISR) { xTaskIncrementTick(); diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 1d502e890e..22fd6e6c67 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -12,7 +12,7 @@ This initial commit contains the information required to build with System Tick Further commits can add support for 16-bit Timers available on many relevant devices. The availability of these 16-bit Timers is somewhat device specific, and these complex and highly configurable Timers are often used to generate phase correct PWM timing (for example) and they would be wasted as a simple System Tick. -The port also provides support for the 3 byte program counter devices __ATmega2560__ and __ATmega2561__. Specific to these two devices the `RAMPZ` and `EIND` registers need to be preserved during a context switch. Also, due to a limitation in GCC, the scheduler needs to reside in the lower 128kB of flash for both of these devices. This is achieved by adding the `.lowtext` section attribute to the function prototype. +The port also provides support for the 3 byte program counter devices __ATmega2560__ and __ATmega2561__. Specific to these two devices the `EIND` register need to be preserved during a context switch. Also, due to a limitation in GCC, the scheduler needs to reside in the lower 128kB of flash for both of these devices. This is achieved by adding the `.lowtext` section attribute to the function prototype. To build generic Microchip (AVR) ATmega support the similarities across the family must be considered, and differences respected. Some comments on the strategy follow. @@ -37,6 +37,8 @@ The ATtiny, ATmega, ATxmega families can optionally support both 3 byte PC and 3 - providing `portSAVE_CONTEXT()` and `portRESTORE_CONTEXT` saving both the __RAMPZ__ and __EIND__ registers. - providing a `portTASK_FUNCTION_PROTO()` with the linker attribute `.lowtext` which is used to ensure that the scheduler and relevant functions remain in the lower 128kB of Flash. +For devices which can support __XRAM__ and have the __RAMPZ__ register, this register is also preserved during the context switch. +

Interrupt Nesting

The ATmega family does not support interrupt nesting, having only one interrupt priority. This means that when the Scheduler is running, interrupts are normally disabled. @@ -61,6 +63,8 @@ if( __malloc_heap_end == 0 ) ``` Unfortunately in the repository there is nowhere sensible to include this statement as it should be included early in the `main()` function. +For devices which can support __XRAM__ the user will need to tune the location of stack and heap according to their own requirements. +

Supported Devices

ATmega devices with __ENHANCED WDT__ Interrupt capability - will use WDT. From 52e6dfbd31da51ce39651306ef4d41b252f8b869 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 18:19:12 +1000 Subject: [PATCH 12/24] Note megaAVR 0-Series is unsupported. --- portable/GCC/ATmegaxxxx/readme.md | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 22fd6e6c67..8a12d1247c 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -79,6 +79,9 @@ ATmega devices with __ENHANCED WDT__ Interrupt capability - will use WDT. ATmega devices without enhanced __WDT__ Interrupt capability - will use Timer0. - ATmega8A/16A/32A/64A/128A -> 4kB RAM - - ATmega808/809/1608/1609/3208/3209/4808/4809 -> 6kB RAM - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM + + ATmega devices withoutavr-libc support - unsupported at this stage. + + - ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM From 10fcd90af1bd62ce88e21de45bd9dc95abd9c31a Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 18:25:02 +1000 Subject: [PATCH 13/24] ATmegaxxxx - remove Timer2 references --- portable/GCC/ATmegaxxxx/port.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 7889e68b1f..e9728239c3 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -729,10 +729,12 @@ void vPortYieldFromTick( void ) __attribute__ ( ( hot, flatten, naked ) ); void vPortYieldFromTick( void ) { portSAVE_CONTEXT(); + if( xTaskIncrementTick() != pdFALSE ) { vTaskSwitchContext(); } + portRESTORE_CONTEXT(); __asm__ __volatile__ ( "ret" ); @@ -748,11 +750,6 @@ void prvSetupTimerInterrupt( void ) /* reset watchdog */ wdt_reset(); - /* actual port tick rate in Hz, calculated */ - portTickRateHz = configTICK_RATE_HZ; - /* initialise first second of ticks */ - ticksRemainingInSec = portTickRateHz; - /* set up WDT Interrupt (rather than the WDT Reset). */ wdt_interrupt_enable( portUSE_WDTO ); } @@ -774,11 +771,6 @@ uint8_t ucLowByte; /* We only have 8 bits so have to scale 1024 to get our required tick rate. */ ulCompareMatch /= portCLOCK_PRESCALER; - /* actual port tick rate in Hz, calculated */ - portTickRateHz = (TickType_t) ((uint32_t) configCPU_CLOCK_HZ / ( portCLOCK_PRESCALER * ulCompareMatch )); - /* initialise first second of ticks */ - ticksRemainingInSec = portTickRateHz; - /* Adjust for correct value. */ ulCompareMatch -= ( uint32_t ) 1; From 62682ebe5b0638057fe2b773c8ee3ee5a694e9cb Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 18:37:00 +1000 Subject: [PATCH 14/24] ATmegaxxxx - clarify initial stack setup --- portable/GCC/ATmegaxxxx/port.c | 53 +++++++++++++++------------------- 1 file changed, 23 insertions(+), 30 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index e9728239c3..1186791eb2 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -1,6 +1,6 @@ /* * FreeRTOS Kernel V10.3.1 - * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in @@ -206,7 +206,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * Macro to save all the general purpose registers, the save the stack pointer * into the TCB. * - * The first thing we do is save the flags then disable interrupts. This is to + * The first thing we do is save the flags then disable interrupts. This is to * guard our stack against having a context switch interrupt after we have already * pushed the registers onto the stack - causing the 32 registers to be on the * stack twice. @@ -221,7 +221,7 @@ void wdt_interrupt_reset_enable (const uint8_t value) * #endif * * #if defined(__AVR_3_BYTE_PC__) - * #define __EIND__ 0x3C + * #define __EIND__ 0x3C * #endif * * The interrupts will have been disabled during the call to portSAVE_CONTEXT() @@ -542,35 +542,28 @@ uint16_t usAddress; /* The start of the task code will be popped off the stack last, so place it on first. */ + usAddress = ( uint16_t ) pxCode; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + + usAddress >>= 8; + *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); + pxTopOfStack--; + #if defined(__AVR_3_BYTE_PC__) /* The AVR ATmega2560/ATmega2561 have 256KBytes of program memory and a 17-bit - * program counter. When a code address is stored on the stack, it takes 3 bytes + * program counter. When a code address is stored on the stack, it takes 3 bytes * instead of 2 for the other ATmega* chips. * * Store 0 as the top byte since we force all task routines to the bottom 128K * of flash. We do this by using the .lowtext label in the linker script. * * In order to do this properly, we would need to get a full 3-byte pointer to - * pxCode. That requires a change to GCC. Not likely to happen any time soon. + * pxCode. That requires a change to GCC. Not likely to happen any time soon. */ - usAddress = ( uint16_t ) pxCode; - *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); - pxTopOfStack--; - - usAddress >>= 8; - *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); - pxTopOfStack--; *pxTopOfStack = 0; pxTopOfStack--; -#else - usAddress = ( uint16_t ) pxCode; - *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); - pxTopOfStack--; - - usAddress >>= 8; - *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); - pxTopOfStack--; #endif /* Next simulate the stack as if after a call to portSAVE_CONTEXT(). @@ -598,7 +591,7 @@ uint16_t usAddress; pxTopOfStack--; #endif - /* Now the remaining registers. The compiler expects R1 to be 0. */ + /* Now the remaining registers. The compiler expects R1 to be 0. */ *pxTopOfStack = ( StackType_t ) 0x00; /* R1 */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x02; /* R2 */ @@ -680,7 +673,7 @@ BaseType_t xPortStartScheduler( void ) /* Restore the context of the first task that is going to run. */ portRESTORE_CONTEXT(); - /* Simulate a function call end as generated by the compiler. We will now + /* Simulate a function call end as generated by the compiler. We will now jump to the start of the task the context of which we have just restored. */ __asm__ __volatile__ ( "ret" ); @@ -705,7 +698,7 @@ void vPortEndScheduler( void ) /*-----------------------------------------------------------*/ /* - * Manual context switch. The first thing we do is save the registers so we + * Manual context switch. The first thing we do is save the registers so we * can use a naked attribute. */ void vPortYield( void ) __attribute__ ( ( hot, flatten, naked ) ); @@ -720,8 +713,8 @@ void vPortYield( void ) /*-----------------------------------------------------------*/ /* - * Context switch function used by the tick. This must be identical to - * vPortYield() from the call to vTaskSwitchContext() onwards. The only + * Context switch function used by the tick. This must be identical to + * vPortYield() from the call to vTaskSwitchContext() onwards. The only * difference from vPortYield() is the tick count is incremented as the * call comes from the tick ISR. */ @@ -774,7 +767,7 @@ uint8_t ucLowByte; /* Adjust for correct value. */ ulCompareMatch -= ( uint32_t ) 1; - /* Setup compare match value for compare match A. Interrupts are disabled + /* Setup compare match value for compare match A. Interrupts are disabled before this is called so we need not worry here. */ ucLowByte = ( uint8_t ) ( ulCompareMatch & ( uint32_t ) 0xff ); portOCRL = ucLowByte; @@ -798,8 +791,8 @@ uint8_t ucLowByte; #if configUSE_PREEMPTION == 1 /* - * Tick ISR for preemptive scheduler. We can use a naked attribute as - * the context is saved at the start of vPortYieldFromTick(). The tick + * Tick ISR for preemptive scheduler. We can use a naked attribute as + * the context is saved at the start of vPortYieldFromTick(). The tick * count is incremented after the context is saved. * * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. @@ -816,8 +809,8 @@ uint8_t ucLowByte; #else /* - * Tick ISR for the cooperative scheduler. All this does is increment the - * tick count. We don't need to switch context, this can only be done by + * Tick ISR for the cooperative scheduler. All this does is increment the + * tick count. We don't need to switch context, this can only be done by * manual calls to taskYIELD(); * * use ISR_NOBLOCK where there is an important timer running, that should preempt the scheduler. From becc1d8b931e1ebdbde68f54ea909015bdd7ded2 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 19:16:31 +1000 Subject: [PATCH 15/24] ATmegaxxx - match legacy whitespace --- portable/GCC/ATmegaxxxx/port.c | 14 +++++--------- portable/GCC/ATmegaxxxx/portmacro.h | 2 -- 2 files changed, 5 insertions(+), 11 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 1186791eb2..c79e7a6fe0 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -67,12 +67,6 @@ any details of its type. */ typedef void TCB_t; extern volatile TCB_t * volatile pxCurrentTCB; -/*-----------------------------------------------------------*/ -/* - * Perform hardware setup to enable ticks from timer compare match A. - */ -static void prvSetupTimerInterrupt( void ); - /*-----------------------------------------------------------*/ /** @@ -518,6 +512,11 @@ void wdt_interrupt_reset_enable (const uint8_t value) #endif /*-----------------------------------------------------------*/ +/* + * Perform hardware setup to enable ticks from relevant Timer. + */ +static void prvSetupTimerInterrupt( void ); +/*-----------------------------------------------------------*/ /* * See header file for description. @@ -541,7 +540,6 @@ uint16_t usAddress; /* The start of the task code will be popped off the stack last, so place it on first. */ - usAddress = ( uint16_t ) pxCode; *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); pxTopOfStack--; @@ -722,12 +720,10 @@ void vPortYieldFromTick( void ) __attribute__ ( ( hot, flatten, naked ) ); void vPortYieldFromTick( void ) { portSAVE_CONTEXT(); - if( xTaskIncrementTick() != pdFALSE ) { vTaskSwitchContext(); } - portRESTORE_CONTEXT(); __asm__ __volatile__ ( "ret" ); diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index 253f1379ae..a9ac7b633a 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -63,7 +63,6 @@ typedef uint8_t UBaseType_t; /*-----------------------------------------------------------*/ /* Critical section management. */ - #define portENTER_CRITICAL() __asm__ __volatile__ ( \ "in __tmp_reg__, __SREG__" "\n\t" \ "cli" "\n\t" \ @@ -81,7 +80,6 @@ typedef uint8_t UBaseType_t; #define portDISABLE_INTERRUPTS() __asm__ __volatile__ ( "cli" ::: "memory") #define portENABLE_INTERRUPTS() __asm__ __volatile__ ( "sei" ::: "memory") - /*-----------------------------------------------------------*/ /* Architecture specifics. */ From 2bbd93595ea273e0e27b7cad43e828aafdd355d4 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 19:50:31 +1000 Subject: [PATCH 16/24] ATmega - update readme.md --- portable/GCC/ATmegaxxxx/readme.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 8a12d1247c..009004e97d 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -82,6 +82,6 @@ ATmega devices without enhanced __WDT__ Interrupt capability - will use Timer0. - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM - ATmega devices withoutavr-libc support - unsupported at this stage. + ATmega devices without avr-libc support - unsupported at this stage. - ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM From 7a9398e511a227e810dec0b3569806c7e88ac5a1 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 20:03:45 +1000 Subject: [PATCH 17/24] ATmegaxxxx - whitespace --- portable/GCC/ATmegaxxxx/port.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index c79e7a6fe0..59615162a5 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -1,6 +1,6 @@ /* * FreeRTOS Kernel V10.3.1 - * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in @@ -656,7 +656,7 @@ uint16_t usAddress; pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x30; /* R30 Z */ pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x031; /* R31 */ + *pxTopOfStack = ( StackType_t ) 0x031; /* R31 */ pxTopOfStack--; return pxTopOfStack; From bfa49e1ea07bc3fa44dc41d7ca7c8430fb145bfc Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Sat, 11 Apr 2020 20:44:12 +1000 Subject: [PATCH 18/24] ATmegaxxxx - whitespace --- portable/GCC/ATmegaxxxx/port.c | 1 - portable/GCC/ATmegaxxxx/portmacro.h | 4 +++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 59615162a5..47dc58d2b7 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -559,7 +559,6 @@ uint16_t usAddress; * In order to do this properly, we would need to get a full 3-byte pointer to * pxCode. That requires a change to GCC. Not likely to happen any time soon. */ - *pxTopOfStack = 0; pxTopOfStack--; #endif diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index a9ac7b633a..ad92b0858d 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -43,6 +43,7 @@ extern "C" { */ /* Type definitions. */ + #define portCHAR char #define portFLOAT float #define portDOUBLE double @@ -63,6 +64,7 @@ typedef uint8_t UBaseType_t; /*-----------------------------------------------------------*/ /* Critical section management. */ + #define portENTER_CRITICAL() __asm__ __volatile__ ( \ "in __tmp_reg__, __SREG__" "\n\t" \ "cli" "\n\t" \ @@ -118,7 +120,7 @@ typedef uint8_t UBaseType_t; #if defined( portUSE_WDTO ) #define portTICK_PERIOD_MS ( (TickType_t) _BV( portUSE_WDTO + 4 ) ) #else -#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) +#define portTICK_PERIOD_MS ( (TickType_t) 1000 / configTICK_RATE_HZ ) #endif #define portBYTE_ALIGNMENT 1 From d381f654fbf4b0893206a1ed8b90a33ac25ed97b Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 14 Apr 2020 09:08:16 +1000 Subject: [PATCH 19/24] Add avr/wdt.h --- portable/GCC/ATmegaxxxx/portmacro.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index ad92b0858d..9a520d5093 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -42,6 +42,8 @@ extern "C" { *----------------------------------------------------------- */ +#include + /* Type definitions. */ #define portCHAR char From db234a6cc109f704dd2f6d2476173aba7ba7b713 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 14 Apr 2020 14:27:33 +1000 Subject: [PATCH 20/24] ATmegaxxxx - add megaAVR 0-Series support --- portable/GCC/ATmegaxxxx/port.c | 95 +++++++---------------------- portable/GCC/ATmegaxxxx/portmacro.h | 2 - 2 files changed, 23 insertions(+), 74 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index 47dc58d2b7..d65cfedc21 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -27,6 +27,8 @@ #include + +#include #include #include @@ -524,17 +526,6 @@ static void prvSetupTimerInterrupt( void ); StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) { uint16_t usAddress; - - /* Place a few bytes of known values on the bottom of the stack. - This is just useful for debugging. */ - - *pxTopOfStack = 0x11; - pxTopOfStack--; - *pxTopOfStack = 0x22; - pxTopOfStack--; - *pxTopOfStack = 0x33; - pxTopOfStack--; - /* Simulate how the stack would look after a call to vPortYield() generated by the compiler. */ @@ -590,51 +581,9 @@ uint16_t usAddress; /* Now the remaining registers. The compiler expects R1 to be 0. */ *pxTopOfStack = ( StackType_t ) 0x00; /* R1 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x02; /* R2 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x03; /* R3 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x04; /* R4 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x05; /* R5 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x06; /* R6 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x07; /* R7 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x08; /* R8 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x09; /* R9 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x10; /* R10 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x11; /* R11 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x12; /* R12 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x13; /* R13 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x14; /* R14 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x15; /* R15 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x16; /* R16 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x17; /* R17 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x18; /* R18 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x19; /* R19 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x20; /* R20 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x21; /* R21 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x22; /* R22 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x23; /* R23 */ - pxTopOfStack--; + + /* Leave R2 - R23 untouched */ + pxTopOfStack -= 23; /* Place the parameter on the stack in the expected location. */ usAddress = ( uint16_t ) pvParameters; @@ -643,20 +592,9 @@ uint16_t usAddress; usAddress >>= 8; *pxTopOfStack = ( StackType_t ) ( usAddress & ( uint16_t ) 0x00ff ); - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x26; /* R26 X */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x27; /* R27 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x28; /* R28 Y */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x29; /* R29 */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x30; /* R30 Z */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) 0x031; /* R31 */ - pxTopOfStack--; + /* Leave register R26 - R31 untouched */ + pxTopOfStack -= 7; return pxTopOfStack; } @@ -709,6 +647,21 @@ void vPortYield( void ) } /*-----------------------------------------------------------*/ +/* + * Manual context switch callable from ISRs. The first thing we do is save + * the registers so we can use a naked attribute. + */ +void vPortYieldFromISR(void) __attribute__ ( ( hot, flatten, naked ) ); +void vPortYieldFromISR(void) +{ + portSAVE_CONTEXT(); + vTaskSwitchContext(); + portRESTORE_CONTEXT(); + + __asm__ __volatile__ ( "reti" ); +} +/*-----------------------------------------------------------*/ + /* * Context switch function used by the tick. This must be identical to * vPortYield() from the call to vTaskSwitchContext() onwards. The only @@ -725,7 +678,7 @@ void vPortYieldFromTick( void ) } portRESTORE_CONTEXT(); - __asm__ __volatile__ ( "ret" ); + __asm__ __volatile__ ( "reti" ); } /*-----------------------------------------------------------*/ @@ -776,7 +729,6 @@ uint8_t ucLowByte; ucLowByte = portTIMSK; ucLowByte |= portCOMPARE_MATCH_A_INTERRUPT_ENABLE; portTIMSK = ucLowByte; - } #endif @@ -799,7 +751,6 @@ uint8_t ucLowByte; ISR(portSCHEDULER_ISR) { vPortYieldFromTick(); - __asm__ __volatile__ ( "reti" ); } #else diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index 9a520d5093..a6f26f5155 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -45,7 +45,6 @@ extern "C" { #include /* Type definitions. */ - #define portCHAR char #define portFLOAT float #define portDOUBLE double @@ -152,4 +151,3 @@ extern void vPortYield( void ) __attribute__ ( ( naked ) ); #endif #endif /* PORTMACRO_H */ - From 98edb54ca3d557cceab11203f784bc64487b2be8 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 14 Apr 2020 14:35:42 +1000 Subject: [PATCH 21/24] ATmegaxxxx - update readme on megaAVR --- portable/GCC/ATmegaxxxx/readme.md | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 009004e97d..02bdde5ac6 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -8,7 +8,8 @@ This port provides a basis for supporting all modern ATmega devices using either This initial commit contains the information required to build with System Tick being generated by either the: - Watchdog Timer, or -- Timer0 - an 8-bit Timer +- Timer0 - an 8-bit Timer, or +- TimerN - a 16-bit Timer which will be configured by the user. Further commits can add support for 16-bit Timers available on many relevant devices. The availability of these 16-bit Timers is somewhat device specific, and these complex and highly configurable Timers are often used to generate phase correct PWM timing (for example) and they would be wasted as a simple System Tick. @@ -20,9 +21,9 @@ To build generic Microchip (AVR) ATmega support the similarities across the fami The Microchip (AVR) ATmega family has limited Timer and Pin capabilities, and is designed to be used in physical applications, controlling hardware with PWM and recognising level and edge voltage changes. It does this mainly through the use of 16-bit Timers (for generating phase correct PWM by up/down counting), and Pins attached to Interrupts. The 8-bit Timers are also attached to Pins, and they can be used for more simple timing tasks, requiring only a single counting direction. -The Timers not attached to Pins (and therefore not impacting the application of the device) are an additional 16-bit Timer (very device dependent, eg Timer3 on 1284p), and the Watch Dog Timer. +The Timers not attached to Pins (and therefore not impacting the application of the device) are some 16-bit Timers (very device dependent, eg Timer3 on 1284p), The RTC Timer, and the Watch Dog Timer. -The Watch Dog Timer is configured identically across the entire range of ATmega devices. It comes in two variants. 1. Old style (eg ATmega32) which does not have an Interrupt capability, and hence on these old devices cannot be used as the System Tick. and 2. New style enhanced WDT, which can generate an Interrupt, and is available on every relevant device. +The Watch Dog Timer is configured identically across most of the ATmega devices. It comes in two variants. 1. Old style (eg ATmega32) which does not have an Interrupt capability, and hence on these old devices cannot be used as the System Tick. and 2. New style enhanced WDT, which can generate an Interrupt, and is available on every relevant device. Using the Watch Dog Timer (WDT) to generate the System Tick does not impact its use as a watch dog. It can be configured to generate a System Tick interrupt, and then one period later to Reset the device if the interrupt is not serviced. @@ -76,12 +77,10 @@ ATmega devices with __ENHANCED WDT__ Interrupt capability - will use WDT. - ATmega324PB -> 2kB RAM - ATmega640/1280/2560/1281/2561 - Arduino Mega -> __8kB RAM + XRAM__ -ATmega devices without enhanced __WDT__ Interrupt capability - will use Timer0. +ATmega devices without enhanced __WDT__ Interrupt capability - will use a 8-bit or 16-bit Timer. - ATmega8A/16A/32A/64A/128A -> 4kB RAM - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM +- ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM - ATmega devices without avr-libc support - unsupported at this stage. - - - ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM From 16f96a8f33e549820123051d46978c740c2afe08 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 14 Apr 2020 14:38:20 +1000 Subject: [PATCH 22/24] ATmegaxxxx - update readme on megaAVR --- portable/GCC/ATmegaxxxx/readme.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/portable/GCC/ATmegaxxxx/readme.md b/portable/GCC/ATmegaxxxx/readme.md index 02bdde5ac6..4afb4fe159 100644 --- a/portable/GCC/ATmegaxxxx/readme.md +++ b/portable/GCC/ATmegaxxxx/readme.md @@ -82,5 +82,5 @@ ATmega devices without enhanced __WDT__ Interrupt capability - will use a 8-bit - ATmega8A/16A/32A/64A/128A -> 4kB RAM - ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P -> 4kB RAM - ATmega169A/169PA/329A/329PA/3290A/3290PA/649A/649P/6490A/6490P -> 4kB RAM -- ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM + - ATmega808/809/1608/1609/3208/3209/4808/4809 - megaAVR 0-Series -> 6kB RAM From 7b02dd55b6423a9ae6a46a4cdf3fbd443a209ea3 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Tue, 14 Apr 2020 20:36:14 +1000 Subject: [PATCH 23/24] ATmegaxxxx - reti fix --- portable/GCC/ATmegaxxxx/port.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c index d65cfedc21..270319ce83 100644 --- a/portable/GCC/ATmegaxxxx/port.c +++ b/portable/GCC/ATmegaxxxx/port.c @@ -678,7 +678,7 @@ void vPortYieldFromTick( void ) } portRESTORE_CONTEXT(); - __asm__ __volatile__ ( "reti" ); + __asm__ __volatile__ ( "ret" ); } /*-----------------------------------------------------------*/ @@ -751,6 +751,7 @@ uint8_t ucLowByte; ISR(portSCHEDULER_ISR) { vPortYieldFromTick(); + __asm__ __volatile__ ( "reti" ); } #else From af8ad187f71947b2be9445e56953849d3e13c304 Mon Sep 17 00:00:00 2001 From: Phillip Stevens Date: Wed, 15 Apr 2020 12:42:57 +1000 Subject: [PATCH 24/24] ATmegaxxxx - add portYIELD_FROM_ISR --- portable/GCC/ATmegaxxxx/portmacro.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/portable/GCC/ATmegaxxxx/portmacro.h b/portable/GCC/ATmegaxxxx/portmacro.h index a6f26f5155..b6b5128749 100644 --- a/portable/GCC/ATmegaxxxx/portmacro.h +++ b/portable/GCC/ATmegaxxxx/portmacro.h @@ -131,6 +131,9 @@ typedef uint8_t UBaseType_t; /* Kernel utilities. */ extern void vPortYield( void ) __attribute__ ( ( naked ) ); #define portYIELD() vPortYield() + +extern void vPortYieldFromISR( void ) __attribute__ ( ( naked ) ); +#define portYIELD_FROM_ISR() vPortYieldFromISR() /*-----------------------------------------------------------*/ #if defined(__AVR_3_BYTE_PC__)