Merge patch series "R-Car CAN FD driver enhancements"

Biju Das <biju.das.jz@bp.renesas.com> says:

The CAN FD IP found on RZ/G2L SoC has some HW features different to
that of R-Car. For example, it has multiple resets, dedicated channel
tx and error interrupts, separate global rx and error interrupts
compared to shared irq for R-Car. it does not s ECC error flag
registers and clk post divider present on R-Car.

Similarly, R-Car V3U has 8 channels whereas other SoCs has only 2
channels. Currently all the HW differences are handled by comparing
with chip_id enum.

This patch series aims to replace chip_id with struct
rcar_canfd_hw_info to handle the HW feature differences and driver
data present on both IPs.

The changes are trivial and tested on RZ/G2L SMARC EVK.

This patch series depend upon [1].

[1] https://lore.kernel.org/all/20221025155657.1426948-1-biju.das.jz@bp.renesas.com

changes since v2: https://lore.kernel.org/all/20221026131732.1843105-1-biju.das.jz@bp.renesas.com
 * Replaced data type of max_channels from unsigned int->u8 to save memory.
 * Replaced data type of postdiv from unsigned int->u8 to save memory.

changes since v1: https://lore.kernel.org/all/20221022104357.1276740-1-biju.das.jz@bp.renesas.com
 * Updated commit description for R-Car V3U SoC detection using
   driver data.
 * Replaced data type of max_channels from u32->unsigned int.
 * Replaced multi_global_irqs->shared_global_irqs to make it
   positive checks.
 * Replaced clk_postdiv->postdiv driver data variable.
 * Simplified the calcualtion for fcan_freq.
 * Replaced info->has_gerfl to gpriv->info->has_gerfl and wrapped
   the ECC error flag checks inside a single if statement.
 * Added Rb tag from Geert patch#1,#2,#3 and #5

Link: https://lore.kernel.org/all/20221027082158.95895-1-biju.das.jz@bp.renesas.com
[mkl: only take patches 1...5 to avoid merge conflict]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/rcar/rcar_canfd.c

@@ -41,12 +41,6 @@
 
 #define RCANFD_DRV_NAME			"rcar_canfd"
 
-enum rcanfd_chip_id {
-	RENESAS_RCAR_GEN3 = 0,
-	RENESAS_RZG2L,
-	RENESAS_R8A779A0,
-};
-
 /* Global register bits */
 
 /* RSCFDnCFDGRMCFG */
@@ -522,6 +516,14 @@ enum rcar_canfd_fcanclk {
 
 struct rcar_canfd_global;
 
+struct rcar_canfd_hw_info {
+	u8 max_channels;
+	u8 postdiv;
+	/* hardware features */
+	unsigned shared_global_irqs:1;	/* Has shared global irqs */
+	unsigned multi_channel_irqs:1;	/* Has multiple channel irqs */
+};
+
 /* Channel priv data */
 struct rcar_canfd_channel {
 	struct can_priv can;			/* Must be the first member */
@@ -547,8 +549,7 @@ struct rcar_canfd_global {
 	bool fdmode;			/* CAN FD or Classical CAN only mode */
 	struct reset_control *rstc1;
 	struct reset_control *rstc2;
-	enum rcanfd_chip_id chip_id;
-	u32 max_channels;
+	const struct rcar_canfd_hw_info *info;
 };
 
 /* CAN FD mode nominal rate constants */
@@ -590,10 +591,28 @@ static const struct can_bittiming_const rcar_canfd_bittiming_const = {
 	.brp_inc = 1,
 };
 
+static const struct rcar_canfd_hw_info rcar_gen3_hw_info = {
+	.max_channels = 2,
+	.postdiv = 2,
+	.shared_global_irqs = 1,
+};
+
+static const struct rcar_canfd_hw_info rzg2l_hw_info = {
+	.max_channels = 2,
+	.postdiv = 1,
+	.multi_channel_irqs = 1,
+};
+
+static const struct rcar_canfd_hw_info r8a779a0_hw_info = {
+	.max_channels = 8,
+	.postdiv = 2,
+	.shared_global_irqs = 1,
+};
+
 /* Helper functions */
 static inline bool is_v3u(struct rcar_canfd_global *gpriv)
 {
-	return gpriv->chip_id == RENESAS_R8A779A0;
+	return gpriv->info == &r8a779a0_hw_info;
 }
 
 static inline u32 reg_v3u(struct rcar_canfd_global *gpriv,
@@ -721,7 +740,7 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
 	rcar_canfd_set_mode(gpriv);
 
 	/* Transition all Channels to reset mode */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
 		rcar_canfd_clear_bit(gpriv->base,
 				     RCANFD_CCTR(ch), RCANFD_CCTR_CSLPR);
 
@@ -762,7 +781,7 @@ static void rcar_canfd_configure_controller(struct rcar_canfd_global *gpriv)
 	rcar_canfd_set_bit(gpriv->base, RCANFD_GCFG, cfg);
 
 	/* Channel configuration settings */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
 		rcar_canfd_set_bit(gpriv->base, RCANFD_CCTR(ch),
 				   RCANFD_CCTR_ERRD);
 		rcar_canfd_update_bit(gpriv->base, RCANFD_CCTR(ch),
@@ -1142,7 +1161,7 @@ static irqreturn_t rcar_canfd_global_err_interrupt(int irq, void *dev_id)
 	struct rcar_canfd_global *gpriv = dev_id;
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
 		rcar_canfd_handle_global_err(gpriv, ch);
 
 	return IRQ_HANDLED;
@@ -1174,7 +1193,7 @@ static irqreturn_t rcar_canfd_global_receive_fifo_interrupt(int irq, void *dev_i
 	struct rcar_canfd_global *gpriv = dev_id;
 	u32 ch;
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
 		rcar_canfd_handle_global_receive(gpriv, ch);
 
 	return IRQ_HANDLED;
@@ -1188,7 +1207,7 @@ static irqreturn_t rcar_canfd_global_interrupt(int irq, void *dev_id)
 	/* Global error interrupts still indicate a condition specific
 	 * to a channel. RxFIFO interrupt is a global interrupt.
 	 */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
 		rcar_canfd_handle_global_err(gpriv, ch);
 		rcar_canfd_handle_global_receive(gpriv, ch);
 	}
@@ -1284,7 +1303,7 @@ static irqreturn_t rcar_canfd_channel_interrupt(int irq, void *dev_id)
 	u32 ch;
 
 	/* Common FIFO is a per channel resource */
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
 		rcar_canfd_handle_channel_err(gpriv, ch);
 		rcar_canfd_handle_channel_tx(gpriv, ch);
 	}
@@ -1696,6 +1715,7 @@ static const struct ethtool_ops rcar_canfd_ethtool_ops = {
 static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 				    u32 fcan_freq)
 {
+	const struct rcar_canfd_hw_info *info = gpriv->info;
 	struct platform_device *pdev = gpriv->pdev;
 	struct rcar_canfd_channel *priv;
 	struct net_device *ndev;
@@ -1718,7 +1738,7 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
 	priv->can.clock.freq = fcan_freq;
 	dev_info(&pdev->dev, "can_clk rate is %u\n", priv->can.clock.freq);
 
-	if (gpriv->chip_id == RENESAS_RZG2L) {
+	if (info->multi_channel_irqs) {
 		char *irq_name;
 		int err_irq;
 		int tx_irq;
@@ -1818,6 +1838,7 @@ static void rcar_canfd_channel_remove(struct rcar_canfd_global *gpriv, u32 ch)
 
 static int rcar_canfd_probe(struct platform_device *pdev)
 {
+	const struct rcar_canfd_hw_info *info;
 	void __iomem *addr;
 	u32 sts, ch, fcan_freq;
 	struct rcar_canfd_global *gpriv;
@@ -1826,26 +1847,23 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	int err, ch_irq, g_irq;
 	int g_err_irq, g_recc_irq;
 	bool fdmode = true;			/* CAN FD only mode - default */
-	enum rcanfd_chip_id chip_id;
-	int max_channels;
 	char name[9] = "channelX";
 	int i;
 
-	chip_id = (uintptr_t)of_device_get_match_data(&pdev->dev);
-	max_channels = chip_id == RENESAS_R8A779A0 ? 8 : 2;
+	info = of_device_get_match_data(&pdev->dev);
 
 	if (of_property_read_bool(pdev->dev.of_node, "renesas,no-can-fd"))
 		fdmode = false;			/* Classical CAN only mode */
 
-	for (i = 0; i < max_channels; ++i) {
+	for (i = 0; i < info->max_channels; ++i) {
 		name[7] = '0' + i;
 		of_child = of_get_child_by_name(pdev->dev.of_node, name);
 		if (of_child && of_device_is_available(of_child))
 			channels_mask |= BIT(i);
 		of_node_put(of_child);
 	}
 
-	if (chip_id != RENESAS_RZG2L) {
+	if (info->shared_global_irqs) {
 		ch_irq = platform_get_irq_byname_optional(pdev, "ch_int");
 		if (ch_irq < 0) {
 			/* For backward compatibility get irq by index */
@@ -1879,8 +1897,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	gpriv->pdev = pdev;
 	gpriv->channels_mask = channels_mask;
 	gpriv->fdmode = fdmode;
-	gpriv->chip_id = chip_id;
-	gpriv->max_channels = max_channels;
+	gpriv->info = info;
 
 	gpriv->rstc1 = devm_reset_control_get_optional_exclusive(&pdev->dev,
 								 "rstp_n");
@@ -1917,9 +1934,9 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	}
 	fcan_freq = clk_get_rate(gpriv->can_clk);
 
-	if (gpriv->fcan == RCANFD_CANFDCLK && gpriv->chip_id != RENESAS_RZG2L)
+	if (gpriv->fcan == RCANFD_CANFDCLK)
 		/* CANFD clock is further divided by (1/2) within the IP */
-		fcan_freq /= 2;
+		fcan_freq /= info->postdiv;
 
 	addr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(addr)) {
@@ -1929,7 +1946,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	gpriv->base = addr;
 
 	/* Request IRQ that's common for both channels */
-	if (gpriv->chip_id != RENESAS_RZG2L) {
+	if (info->shared_global_irqs) {
 		err = devm_request_irq(&pdev->dev, ch_irq,
 				       rcar_canfd_channel_interrupt, 0,
 				       "canfd.ch_int", gpriv);
@@ -1995,7 +2012,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	rcar_canfd_configure_controller(gpriv);
 
 	/* Configure per channel attributes */
-	for_each_set_bit(ch, &gpriv->channels_mask, max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
 		/* Configure Channel's Rx fifo */
 		rcar_canfd_configure_rx(gpriv, ch);
 
@@ -2021,7 +2038,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 		goto fail_mode;
 	}
 
-	for_each_set_bit(ch, &gpriv->channels_mask, max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
 		err = rcar_canfd_channel_probe(gpriv, ch, fcan_freq);
 		if (err)
 			goto fail_channel;
@@ -2033,7 +2050,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	return 0;
 
 fail_channel:
-	for_each_set_bit(ch, &gpriv->channels_mask, max_channels)
+	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels)
 		rcar_canfd_channel_remove(gpriv, ch);
 fail_mode:
 	rcar_canfd_disable_global_interrupts(gpriv);
@@ -2054,7 +2071,7 @@ static int rcar_canfd_remove(struct platform_device *pdev)
 	rcar_canfd_reset_controller(gpriv);
 	rcar_canfd_disable_global_interrupts(gpriv);
 
-	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->max_channels) {
+	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
 		rcar_canfd_disable_channel_interrupts(gpriv->ch[ch]);
 		rcar_canfd_channel_remove(gpriv, ch);
 	}
@@ -2082,9 +2099,9 @@ static SIMPLE_DEV_PM_OPS(rcar_canfd_pm_ops, rcar_canfd_suspend,
 			 rcar_canfd_resume);
 
 static const __maybe_unused struct of_device_id rcar_canfd_of_table[] = {
-	{ .compatible = "renesas,rcar-gen3-canfd", .data = (void *)RENESAS_RCAR_GEN3 },
-	{ .compatible = "renesas,rzg2l-canfd", .data = (void *)RENESAS_RZG2L },
-	{ .compatible = "renesas,r8a779a0-canfd", .data = (void *)RENESAS_R8A779A0 },
+	{ .compatible = "renesas,rcar-gen3-canfd", .data = &rcar_gen3_hw_info },
+	{ .compatible = "renesas,rzg2l-canfd", .data = &rzg2l_hw_info },
+	{ .compatible = "renesas,r8a779a0-canfd", .data = &r8a779a0_hw_info },
 	{ }
 };