On Thu, Jun 16, 2022 at 06:14:29PM +0530, Bharat Kumar Gogada wrote:
> 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 | 62 ++++++++++++++++++++++--
> 1 file changed, 59 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-xilinx-cpm.c b/drivers/pci/controller/pcie-xilinx-cpm.c
> index c7cd44ed4dfc..0bcd11d27eeb 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
> @@ -98,6 +102,16 @@
> /* Phy Status/Control Register definitions */
> #define XILINX_CPM_PCIE_REG_PSCR_LNKUP BIT(11)
>
> +/**
> + * struct xilinx_cpm_variant - CPM variant information
> + * @cpm_version: CPM5 has few changes compared to CPM block.
> + * CPM5 has dedicated register space for control and status registers.
> + *
Superfluous blank line.
> + */
> +struct xilinx_cpm_variant {
> + bool cpm_version;
This is not really a bool, unless you want to preclude the possibility
of ever having a CPM6 or other future variants.
> +};
> +
> /**
> * struct xilinx_cpm_pcie - PCIe port information
> * @dev: Device pointer
> @@ -109,6 +123,7 @@
> * @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 +135,7 @@ 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 +301,14 @@ 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 +508,12 @@ 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,
> @@ -503,6 +533,10 @@ static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie *port,
> struct device *dev = port->dev;
> struct platform_device *pdev = to_platform_device(dev);
> struct resource *res;
> + const struct xilinx_cpm_variant *variant =
> + of_device_get_match_data(dev);
> +
> + port->is_cpm5 = variant->cpm_version;
It's a little clunky to use booleans for a potentially multi-valued
version and to copy them around. Something like this might leave room
for future variants that need more knobs:
enum xilinx_cpm_version {
CPM,
CPM5,
};
struct xilinx_cpm_variant {
enum xilinx_cpm_version version;
};
struct xilinx_cpm_pcie {
...
const struct xilinx_cpm_variant *variant;
static const struct xilinx_cpm_variant cpm5 = {
.version = CPM5,
};
xilinx_cpm_pcie_event_flow()
{
...
if (port->variant->version == CPM5)
xilinx_cpm_pcie_probe()
{
...
port->variant = of_device_get_match_data(dev);
> port->cpm_base = devm_platform_ioremap_resource_byname(pdev,
> "cpm_slcr");
> @@ -518,7 +552,14 @@ 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 = devm_platform_ioremap_resource_byname(pdev,
> + "cpm_csr");
> + if (IS_ERR(port->reg_base))
> + return PTR_ERR(port->reg_base);
> + } else {
> + port->reg_base = port->cfg->win;
> + }
>
> return 0;
> }
> @@ -591,9 +632,24 @@ static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
> return err;
> }
>
> +static const struct xilinx_cpm_variant cpm_host = {
> + .cpm_version = false,
> +};
> +
> +static const struct xilinx_cpm_variant cpm5_host = {
> + .cpm_version = true,
> +};
> +
> static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
> - { .compatible = "xlnx,versal-cpm-host-1.00", },
> - {}
> + {
> + .compatible = "xlnx,versal-cpm-host-1.00",
> + .data = &cpm_host,
> + },
> + {
> + .compatible = "xlnx,versal-cpm5-host",
> + .data = &cpm5_host,
> + },
> + {},
> };
>
> static struct platform_driver xilinx_cpm_pcie_driver = {
> --
> 2.17.1
>
