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

From: Bharat Kumar Gogada
Date: Fri Feb 04 2022 - 08:06:12 EST


Xilinx Versal Premium series has CPM5 block which supports Root port
functioning at Gen5 speed.
Xilinx Versal CPM5 has few changes with existing CPM block.
- CPM5 has dedicated register space for control and status registers.
- CPM5 legacy interrupt handling needs additional register bit
to enable and handle legacy interrupts.

Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
---
drivers/pci/controller/pcie-xilinx-cpm.c | 33 +++++++++++++++++++++++-
1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-xilinx-cpm.c b/drivers/pci/controller/pcie-xilinx-cpm.c
index c7cd44ed4dfc..eb69f494571a 100644
--- a/drivers/pci/controller/pcie-xilinx-cpm.c
+++ b/drivers/pci/controller/pcie-xilinx-cpm.c
@@ -35,6 +35,10 @@
#define XILINX_CPM_PCIE_MISC_IR_ENABLE 0x00000348
#define XILINX_CPM_PCIE_MISC_IR_LOCAL BIT(1)

+#define XILINX_CPM_PCIE_IR_STATUS 0x000002A0
+#define XILINX_CPM_PCIE_IR_ENABLE 0x000002A8
+#define XILINX_CPM_PCIE_IR_LOCAL BIT(0)
+
/* Interrupt registers definitions */
#define XILINX_CPM_PCIE_INTR_LINK_DOWN 0
#define XILINX_CPM_PCIE_INTR_HOT_RESET 3
@@ -109,6 +113,7 @@
* @intx_irq: legacy interrupt number
* @irq: Error interrupt number
* @lock: lock protecting shared register access
+ * @is_cpm5: value to check cpm version
*/
struct xilinx_cpm_pcie {
struct device *dev;
@@ -120,6 +125,7 @@ struct xilinx_cpm_pcie {
int intx_irq;
int irq;
raw_spinlock_t lock;
+ bool is_cpm5;
};

static u32 pcie_read(struct xilinx_cpm_pcie *port, u32 reg)
@@ -285,6 +291,14 @@ 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->is_cpm5) {
+ val = readl_relaxed(port->cpm_base + XILINX_CPM_PCIE_IR_STATUS);
+ if (val)
+ writel_relaxed(val,
+ port->cpm_base +
+ XILINX_CPM_PCIE_IR_STATUS);
+ }
+
/*
* XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
* CPM SLCR block.
@@ -484,6 +498,12 @@ static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie *port)
*/
writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
+
+ if (port->is_cpm5) {
+ writel(XILINX_CPM_PCIE_IR_LOCAL,
+ port->cpm_base + XILINX_CPM_PCIE_IR_ENABLE);
+ }
+
/* Enable the Bridge enable bit */
pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
XILINX_CPM_PCIE_REG_RPSC_BEN,
@@ -504,6 +524,9 @@ static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie *port,
struct platform_device *pdev = to_platform_device(dev);
struct resource *res;

+ if (of_device_is_compatible(dev->of_node, "xlnx,versal-cpm5-host-1.00"))
+ port->is_cpm5 = true;
+
port->cpm_base = devm_platform_ioremap_resource_byname(pdev,
"cpm_slcr");
if (IS_ERR(port->cpm_base))
@@ -518,7 +541,14 @@ static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie *port,
if (IS_ERR(port->cfg))
return PTR_ERR(port->cfg);

- port->reg_base = port->cfg->win;
+ if (!port->is_cpm5) {
+ port->reg_base = port->cfg->win;
+ } else {
+ port->reg_base = devm_platform_ioremap_resource_byname(pdev,
+ "cpm_csr");
+ if (IS_ERR(port->reg_base))
+ return PTR_ERR(port->reg_base);
+ }

return 0;
}
@@ -593,6 +623,7 @@ static int xilinx_cpm_pcie_probe(struct platform_device *pdev)

static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
{ .compatible = "xlnx,versal-cpm-host-1.00", },
+ { .compatible = "xlnx,versal-cpm5-host-1.00", },
{}
};

--
2.17.1