can: rcar_canfd: Add RZ/G3E support

The CAN-FD IP found on the RZ/G3E SoC is similar to R-Car Gen4, but
it has no external clock instead it has clk_ram, it has 6 channels
and supports 20 interrupts. Add support for RZ/G3E CAN-FD driver.

Reviewed-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Vincent Mailhol <[email protected]>
Signed-off-by: Biju Das <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Marc Kleine-Budde <[email protected]>

Author: bijudas

drivers/net/can/rcar/rcar_canfd.c

@@ -726,6 +726,22 @@ static const struct rcar_canfd_hw_info rzg2l_hw_info = {
 	.external_clk = 1,
 };
 
+static const struct rcar_canfd_hw_info r9a09g047_hw_info = {
+	.nom_bittiming = &rcar_canfd_gen4_nom_bittiming_const,
+	.data_bittiming = &rcar_canfd_gen4_data_bittiming_const,
+	.regs = &rcar_gen4_regs,
+	.sh = &rcar_gen4_shift_data,
+	.rnc_field_width = 16,
+	.max_aflpn = 63,
+	.max_cftml = 31,
+	.max_channels = 6,
+	.postdiv = 1,
+	.multi_channel_irqs = 1,
+	.ch_interface_mode = 1,
+	.shared_can_regs = 1,
+	.external_clk = 0,
+};
+
 /* Helper functions */
 static inline void rcar_canfd_update(u32 mask, u32 val, u32 __iomem *reg)
 {
@@ -1969,6 +1985,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	u32 rule_entry = 0;
 	bool fdmode = true;			/* CAN FD only mode - default */
 	char name[9] = "channelX";
+	struct clk *clk_ram;
 	int i;
 
 	info = of_device_get_match_data(dev);
@@ -2058,6 +2075,11 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 		gpriv->extclk = gpriv->info->external_clk;
 	}
 
+	clk_ram = devm_clk_get_optional_enabled(dev, "ram_clk");
+	if (IS_ERR(clk_ram))
+		return dev_err_probe(dev, PTR_ERR(clk_ram),
+				     "cannot get enabled ram clock\n");
+
 	addr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(addr)) {
 		err = PTR_ERR(addr);
@@ -2220,6 +2242,7 @@ static SIMPLE_DEV_PM_OPS(rcar_canfd_pm_ops, rcar_canfd_suspend,
 
 static const __maybe_unused struct of_device_id rcar_canfd_of_table[] = {
 	{ .compatible = "renesas,r8a779a0-canfd", .data = &rcar_gen4_hw_info },
+	{ .compatible = "renesas,r9a09g047-canfd", .data = &r9a09g047_hw_info },
 	{ .compatible = "renesas,rcar-gen3-canfd", .data = &rcar_gen3_hw_info },
 	{ .compatible = "renesas,rcar-gen4-canfd", .data = &rcar_gen4_hw_info },
 	{ .compatible = "renesas,rzg2l-canfd", .data = &rzg2l_hw_info },