[PATCH v3 5/8] irqchip/imx-irqsteer: add NXP S32N79 support

[Ciprian Costea <ciprianmarian.costea@oss.nxp.com>]

From: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>

Add support for the interrupt steering controller found in NXP S32N79
series automotive SoCs.

The S32N79 IRQ_STEER variant differs from the i.MX version by not
implementing the CHANCTRL register. To handle this hardware difference,
introduce a device type data structure with quirks field. The
IRQSTEER_QUIRK_NO_CHANCTRL quirk skips CHANCTRL register access for S32N79
variants.

The interrupt routing functionality and register layout are otherwise
identical between the two variants.

Co-developed-by: Larisa Grigore <larisa.grigore@nxp.com>
Signed-off-by: Larisa Grigore <larisa.grigore@nxp.com>
Signed-off-by: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>
---
 drivers/irqchip/irq-imx-irqsteer.c | 35 +++++++++++++++++++++++++++---
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/drivers/irqchip/irq-imx-irqsteer.c b/drivers/irqchip/irq-imx-irqsteer.c
index 4682ce5bf8d3..82e64af87c0b 100644
--- a/drivers/irqchip/irq-imx-irqsteer.c
+++ b/drivers/irqchip/irq-imx-irqsteer.c
@@ -26,6 +26,13 @@
 
 #define CHAN_MAX_OUTPUT_INT	0xF
 
+/* SoC does not implement the CHANCTRL register */
+#define IRQSTEER_QUIRK_NO_CHANCTRL	BIT(0)
+
+struct irqsteer_devtype_data {
+	u32 quirks;
+};
+
 struct irqsteer_data {
 	void __iomem		*regs;
 	struct clk		*ipg_clk;
@@ -37,8 +44,22 @@ struct irqsteer_data {
 	struct irq_domain	*domain;
 	u32			*saved_reg;
 	struct device		*dev;
+	const struct irqsteer_devtype_data *devtype_data;
 };
 
+static const struct irqsteer_devtype_data imx_data = {
+	.quirks = 0,
+};
+
+static const struct irqsteer_devtype_data s32n79_data = {
+	.quirks = IRQSTEER_QUIRK_NO_CHANCTRL,
+};
+
+static bool irqsteer_has_chanctrl(const struct irqsteer_devtype_data *data)
+{
+	return !(data->quirks & IRQSTEER_QUIRK_NO_CHANCTRL);
+}
+
 static int imx_irqsteer_get_reg_index(struct irqsteer_data *data,
 				      unsigned long irqnum)
 {
@@ -188,6 +209,10 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	data->devtype_data = device_get_match_data(&pdev->dev);
+	if (!data->devtype_data)
+		return dev_err_probe(&pdev->dev, -ENODEV,
+				"failed to match device data\n");
 	/*
 	 * There is one output irq for each group of 64 inputs.
 	 * One register bit map can represent 32 input interrupts.
@@ -210,7 +235,8 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 	}
 
 	/* steer all IRQs into configured channel */
-	writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
+	if (irqsteer_has_chanctrl(data->devtype_data))
+		writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
 
 	data->domain = irq_domain_create_linear(dev_fwnode(&pdev->dev), data->reg_num * 32,
 						&imx_irqsteer_domain_ops, data);
@@ -279,7 +305,9 @@ static void imx_irqsteer_restore_regs(struct irqsteer_data *data)
 {
 	int i;
 
-	writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
+	if (irqsteer_has_chanctrl(data->devtype_data))
+		writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
+
 	for (i = 0; i < data->reg_num; i++)
 		writel_relaxed(data->saved_reg[i],
 			       data->regs + CHANMASK(i, data->reg_num));
@@ -319,7 +347,8 @@ static const struct dev_pm_ops imx_irqsteer_pm_ops = {
 };
 
 static const struct of_device_id imx_irqsteer_dt_ids[] = {
-	{ .compatible = "fsl,imx-irqsteer", },
+	{ .compatible = "fsl,imx-irqsteer", .data = &imx_data },
+	{ .compatible = "nxp,s32n79-irqsteer", .data = &s32n79_data },
 	{},
 };
 
-- 
2.43.0