[PATCH v3] irqchip/qcom-pdc: add support for v3.2 HW

[Neil Armstrong]

Starting from HW version 3.2 the IRQ_ENABLE bit has moved to the
IRQ_i_CFG register and requires a change of the driver to avoid
writing into an undefined register address.

Get the HW version from registers and set the IRQ_ENABLE bit to the
correct register depending on the HW version.

Reviewed-by: Maulik Shah <quic_mkshah@xxxxxxxxxxx>
Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
---
Changes in v3:
- Simplify qcom_pdc_gic_set_type()
- Used __assign_bit in pdc_setup_pin_mapping()
- remove BIT() from IRQ_i_CFG_IRQ_ENABLE to be used with __assign_bit()
- Add Reviewed-by tag
- Link to v2: https://lore.kernel.org/r/20230822-topic-sm8x50-upstream-pdc-ver-v2-1-3035b8d388f7@xxxxxxxxxx

Changes in v2:
- Changed IRQ_ENABLE handling based on Maulik's comments
- Link to v1: https://lore.kernel.org/r/20230821-topic-sm8x50-upstream-pdc-ver-v1-1-6d7f4dd95719@xxxxxxxxxx
---
 drivers/irqchip/qcom-pdc.c | 61 ++++++++++++++++++++++++++++++++++++----------
 1 file changed, 48 insertions(+), 13 deletions(-)

diff --git a/drivers/irqchip/qcom-pdc.c b/drivers/irqchip/qcom-pdc.c
index d96916cf6a41..5f60a23686c9 100644
--- a/drivers/irqchip/qcom-pdc.c
+++ b/drivers/irqchip/qcom-pdc.c
@@ -23,9 +23,22 @@
 
 #define PDC_MAX_GPIO_IRQS	256
 
+/* Valid only on HW version < 3.2 */
 #define IRQ_ENABLE_BANK		0x10
 #define IRQ_i_CFG		0x110
 
+/* Valid only on HW version >= 3.2 */
+#define IRQ_i_CFG_IRQ_ENABLE	3
+
+#define IRQ_i_CFG_TYPE_MASK	GENMASK(2, 0)
+
+#define PDC_VERSION		0x1000
+
+/* Notable PDC versions */
+enum {
+	PDC_VERSION_3_2	= 0x30200,
+};
+
 struct pdc_pin_region {
 	u32 pin_base;
 	u32 parent_base;
@@ -38,6 +51,7 @@ static DEFINE_RAW_SPINLOCK(pdc_lock);
 static void __iomem *pdc_base;
 static struct pdc_pin_region *pdc_region;
 static int pdc_region_cnt;
+static unsigned int pdc_version;
 
 static void pdc_reg_write(int reg, u32 i, u32 val)
 {
@@ -54,15 +68,22 @@ static void pdc_enable_intr(struct irq_data *d, bool on)
 	int pin_out = d->hwirq;
 	unsigned long enable;
 	unsigned long flags;
-	u32 index, mask;
-
-	index = pin_out / 32;
-	mask = pin_out % 32;
 
 	raw_spin_lock_irqsave(&pdc_lock, flags);
-	enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
-	__assign_bit(mask, &enable, on);
-	pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
+	if (pdc_version < PDC_VERSION_3_2) {
+		u32 index, mask;
+
+		index = pin_out / 32;
+		mask = pin_out % 32;
+
+		enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
+		__assign_bit(mask, &enable, on);
+		pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
+	} else {
+		enable = pdc_reg_read(IRQ_i_CFG, pin_out);
+		__assign_bit(IRQ_i_CFG_IRQ_ENABLE, &enable, on);
+		pdc_reg_write(IRQ_i_CFG, pin_out, enable);
+	}
 	raw_spin_unlock_irqrestore(&pdc_lock, flags);
 }
 
@@ -143,6 +164,7 @@ static int qcom_pdc_gic_set_type(struct irq_data *d, unsigned int type)
 	}
 
 	old_pdc_type = pdc_reg_read(IRQ_i_CFG, d->hwirq);
+	pdc_type |= (old_pdc_type & ~IRQ_i_CFG_TYPE_MASK);
 	pdc_reg_write(IRQ_i_CFG, d->hwirq, pdc_type);
 
 	ret = irq_chip_set_type_parent(d, type);
@@ -247,7 +269,7 @@ static const struct irq_domain_ops qcom_pdc_ops = {
 static int pdc_setup_pin_mapping(struct device_node *np)
 {
 	int ret, n, i;
-	u32 irq_index, reg_index, val;
+	unsigned long val;
 
 	n = of_property_count_elems_of_size(np, "qcom,pdc-ranges", sizeof(u32));
 	if (n <= 0 || n % 3)
@@ -278,11 +300,22 @@ static int pdc_setup_pin_mapping(struct device_node *np)
 			return ret;
 
 		for (i = 0; i < pdc_region[n].cnt; i++) {
-			reg_index = (i + pdc_region[n].pin_base) >> 5;
-			irq_index = (i + pdc_region[n].pin_base) & 0x1f;
-			val = pdc_reg_read(IRQ_ENABLE_BANK, reg_index);
-			val &= ~BIT(irq_index);
-			pdc_reg_write(IRQ_ENABLE_BANK, reg_index, val);
+			if (pdc_version < PDC_VERSION_3_2) {
+				u32 irq_index, reg_index;
+
+				reg_index = (i + pdc_region[n].pin_base) >> 5;
+				irq_index = (i + pdc_region[n].pin_base) & 0x1f;
+				val = pdc_reg_read(IRQ_ENABLE_BANK, reg_index);
+				__assign_bit(irq_index, &val, 0);
+				pdc_reg_write(IRQ_ENABLE_BANK, reg_index, val);
+			} else {
+				u32 irq;
+
+				irq = i + pdc_region[n].pin_base;
+				val = pdc_reg_read(IRQ_i_CFG, irq);
+				__assign_bit(IRQ_i_CFG_IRQ_ENABLE, &val,  0);
+				pdc_reg_write(IRQ_i_CFG, irq, val);
+			}
 		}
 	}
 
@@ -300,6 +333,8 @@ static int qcom_pdc_init(struct device_node *node, struct device_node *parent)
 		return -ENXIO;
 	}
 
+	pdc_version = pdc_reg_read(PDC_VERSION, 0);
+
 	parent_domain = irq_find_host(parent);
 	if (!parent_domain) {
 		pr_err("%pOF: unable to find PDC's parent domain\n", node);

---
base-commit: 47d9bb711707d15b19fad18c8e2b4b027a264a3a
change-id: 20230821-topic-sm8x50-upstream-pdc-ver-114ceb45e1ee

Best regards,
-- 
Neil Armstrong <neil.armstrong@xxxxxxxxxx>