[PATCH v3 2/2] PCI: xilinx-cpm: Add support for Versal CPM5 Root Port controller 1

[Thippeswamy Havalige <thippesw@amd.com>]

Add support for the Xilinx Versal CPM5 Root Port Controller 1. The key
difference between Controller 0 and Controller 1 lies in the
platform-specific error interrupt bits, which are located at different
register offsets.

To handle these differences, updated variant structure to hold the
following platform-specific details:

- Interrupt status register offset (ir_status)
- Interrupt enable register offset (ir_enable)
- Miscellaneous interrupt values (ir_misc_value)

The driver differentiates between Controller 0 and Controller 1 using the
compatible string in the device tree. This ensures that the appropriate
register offsets are used for each controller, allowing for correct
handling of platform-specific interrupts and initialization.

Signed-off-by: Thippeswamy Havalige <thippesw@amd.com>
---
changes in v3:
--------------
1. Add kernel Documentation for variant structure.
2. Modify compatible string.
changes in v2:
--------------
1. Introduced new constants for Controller 1.
2. Extended the xilinx_cpm_variant structure to support
	a. ir_status,
	b. ir_enable, and 
	c. ir_misc_value for different controllers.
3. Updated IRQ handling and initialization to use the variant structure.
4. Added a new device tree match entry for Controller 1.
---
 drivers/pci/controller/pcie-xilinx-cpm.c | 50 ++++++++++++++++++------
 1 file changed, 39 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/controller/pcie-xilinx-cpm.c b/drivers/pci/controller/pcie-xilinx-cpm.c
index a0f5e1d67b04..81e8bfae53d0 100644
--- a/drivers/pci/controller/pcie-xilinx-cpm.c
+++ b/drivers/pci/controller/pcie-xilinx-cpm.c
@@ -30,11 +30,14 @@
 #define XILINX_CPM_PCIE_REG_IDRN_MASK	0x00000E3C
 #define XILINX_CPM_PCIE_MISC_IR_STATUS	0x00000340
 #define XILINX_CPM_PCIE_MISC_IR_ENABLE	0x00000348
-#define XILINX_CPM_PCIE_MISC_IR_LOCAL	BIT(1)
+#define XILINX_CPM_PCIE0_MISC_IR_LOCAL	BIT(1)
+#define XILINX_CPM_PCIE1_MISC_IR_LOCAL	BIT(2)
 
-#define XILINX_CPM_PCIE_IR_STATUS       0x000002A0
-#define XILINX_CPM_PCIE_IR_ENABLE       0x000002A8
-#define XILINX_CPM_PCIE_IR_LOCAL        BIT(0)
+#define XILINX_CPM_PCIE0_IR_STATUS	0x000002A0
+#define XILINX_CPM_PCIE1_IR_STATUS	0x000002B4
+#define XILINX_CPM_PCIE0_IR_ENABLE	0x000002A8
+#define XILINX_CPM_PCIE1_IR_ENABLE	0x000002BC
+#define XILINX_CPM_PCIE_IR_LOCAL	BIT(0)
 
 #define IMR(x) BIT(XILINX_PCIE_INTR_ ##x)
 
@@ -80,14 +83,21 @@
 enum xilinx_cpm_version {
 	CPM,
 	CPM5,
+	CPM5_HOST1,
 };
 
 /**
  * struct xilinx_cpm_variant - CPM variant information
  * @version: CPM version
+ * @ir_status: Offset for the error interrupt status register
+ * @ir_enable: Offset for the CPM5 local error interrupt enable register
+ * @ir_misc_value: A bitmask for the miscellaneous interrupt status
  */
 struct xilinx_cpm_variant {
 	enum xilinx_cpm_version version;
+	u32 ir_status;
+	u32 ir_enable;
+	u32 ir_misc_value;
 };
 
 /**
@@ -269,6 +279,7 @@ static void xilinx_cpm_pcie_event_flow(struct irq_desc *desc)
 {
 	struct xilinx_cpm_pcie *port = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
+	const struct xilinx_cpm_variant *variant = port->variant;
 	unsigned long val;
 	int i;
 
@@ -279,11 +290,11 @@ static void xilinx_cpm_pcie_event_flow(struct irq_desc *desc)
 		generic_handle_domain_irq(port->cpm_domain, i);
 	pcie_write(port, val, XILINX_CPM_PCIE_REG_IDR);
 
-	if (port->variant->version == CPM5) {
-		val = readl_relaxed(port->cpm_base + XILINX_CPM_PCIE_IR_STATUS);
+	if (variant->ir_status) {
+		val = readl_relaxed(port->cpm_base + variant->ir_status);
 		if (val)
 			writel_relaxed(val, port->cpm_base +
-					    XILINX_CPM_PCIE_IR_STATUS);
+				       variant->ir_status);
 	}
 
 	/*
@@ -465,6 +476,8 @@ static int xilinx_cpm_setup_irq(struct xilinx_cpm_pcie *port)
  */
 static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie *port)
 {
+	const struct xilinx_cpm_variant *variant = port->variant;
+
 	if (cpm_pcie_link_up(port))
 		dev_info(port->dev, "PCIe Link is UP\n");
 	else
@@ -483,15 +496,15 @@ static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie *port)
 	 * XILINX_CPM_PCIE_MISC_IR_ENABLE register is mapped to
 	 * CPM SLCR block.
 	 */
-	writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
+	writel(variant->ir_misc_value,
 	       port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
 
-	if (port->variant->version == CPM5) {
+	if (variant->ir_enable) {
 		writel(XILINX_CPM_PCIE_IR_LOCAL,
-		       port->cpm_base + XILINX_CPM_PCIE_IR_ENABLE);
+		       port->cpm_base + variant->ir_enable);
 	}
 
-	/* Enable the Bridge enable bit */
+	/* Set Bridge enable bit */
 	pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
 		   XILINX_CPM_PCIE_REG_RPSC_BEN,
 		   XILINX_CPM_PCIE_REG_RPSC);
@@ -609,10 +622,21 @@ static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
 
 static const struct xilinx_cpm_variant cpm_host = {
 	.version = CPM,
+	.ir_misc_value = XILINX_CPM_PCIE0_MISC_IR_LOCAL,
 };
 
 static const struct xilinx_cpm_variant cpm5_host = {
 	.version = CPM5,
+	.ir_misc_value = XILINX_CPM_PCIE0_MISC_IR_LOCAL,
+	.ir_status = XILINX_CPM_PCIE0_IR_STATUS,
+	.ir_enable = XILINX_CPM_PCIE0_IR_ENABLE,
+};
+
+static const struct xilinx_cpm_variant cpm5_host1 = {
+	.version = CPM5_HOST1,
+	.ir_misc_value = XILINX_CPM_PCIE1_MISC_IR_LOCAL,
+	.ir_status = XILINX_CPM_PCIE1_IR_STATUS,
+	.ir_enable = XILINX_CPM_PCIE1_IR_ENABLE,
 };
 
 static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
@@ -624,6 +648,10 @@ static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
 		.compatible = "xlnx,versal-cpm5-host",
 		.data = &cpm5_host,
 	},
+	{
+		.compatible = "xlnx,versal-cpm5-host1",
+		.data = &cpm5_host1,
+	},
 	{}
 };
 
-- 
2.34.1