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

Thippeswamy Havalige
2024-09-22T06:18:21Z

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