Re: [PATCH v3 22/26] PCI: keystone: Add support for PCIe EP in AM654x Platforms

Lorenzo Pieralisi
2019-04-26T09:40:17Z

On Mon, Mar 25, 2019 at 03:09:43PM +0530, Kishon Vijay Abraham I wrote:
> Add PCIe EP support for AM654x Platforms in pci-keystone.c
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
> drivers/pci/controller/dwc/Kconfig | 23 +-
> drivers/pci/controller/dwc/pci-keystone.c | 242 +++++++++++++++++++---
> 2 files changed, 236 insertions(+), 29 deletions(-)

Hi Kishon,

WARNING: DT compatible string "ti,am654-pcie-ep" appears un-documented -- check /work/sandbox/pci/Documentation/devicetree/bindings/
#301: FILE: drivers/pci/controller/dwc/pci-keystone.c:1179:
+ .compatible = "ti,am654-pcie-ep",

I would like this warning to be fixed please on this patch.

Thanks,
Lorenzo

> diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
> index d1d00833e0b3..b450ad2823a5 100644
> --- a/drivers/pci/controller/dwc/Kconfig
> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -105,14 +105,33 @@ config PCIE_SPEAR13XX
> config PCI_KEYSTONE
> bool "TI Keystone PCIe controller"
> depends on ARCH_KEYSTONE || ARCH_K3 || ((ARM || ARM64) && COMPILE_TEST)
> - depends on PCI_MSI_IRQ_DOMAIN
> - select PCIE_DW_HOST
> help
> Say Y here if you want to enable PCI controller support on Keystone
> SoCs. The PCI controller on Keystone is based on DesignWare hardware
> and therefore the driver re-uses the DesignWare core functions to
> implement the driver.
>
> +if PCI_KEYSTONE
> +
> +config PCI_KEYSTONE_HOST
> + bool "PCI Keystone Host Mode"
> + depends on PCI_MSI_IRQ_DOMAIN
> + select PCIE_DW_HOST
> + default y
> + help
> + Enables support for the PCIe controller in the Keystone SoC to work in
> + host mode.
> +
> +config PCI_KEYSTONE_EP
> + bool "PCI Keystone Endpoint Mode"
> + depends on PCI_ENDPOINT
> + select PCIE_DW_EP
> + help
> + Enables support for the PCIe controller in the Keystone SoC to work in
> + endpoint mode.
> +
> +endif
> +
> config PCI_LAYERSCAPE
> bool "Freescale Layerscape PCIe controller"
> depends on OF && (ARM || ARCH_LAYERSCAPE || COMPILE_TEST)
> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
> index 312fd0c49bbb..459485b0f65d 100644
> --- a/drivers/pci/controller/dwc/pci-keystone.c
> +++ b/drivers/pci/controller/dwc/pci-keystone.c
> @@ -52,6 +52,12 @@
> #define OB_ENABLEN BIT(0)
> #define OB_WIN_SIZE 8 /* 8MB */
>
> +#define PCIE_LEGACY_IRQ_ENABLE_SET(n) (0x188 + (0x10 * ((n) - 1)))
> +#define PCIE_LEGACY_IRQ_ENABLE_CLR(n) (0x18c + (0x10 * ((n) - 1)))
> +#define PCIE_EP_IRQ_SET 0x64
> +#define PCIE_EP_IRQ_CLR 0x68
> +#define INT_ENABLE BIT(0)
> +
> /* IRQ register defines */
> #define IRQ_EOI 0x050
>
> @@ -95,11 +101,16 @@
> #define KS_PCIE_SYSCLOCKOUTEN BIT(0)
>
> #define AM654_PCIE_DEV_TYPE_MASK 0x3
> +#define AM654_WIN_SIZE SZ_64K
> +
> +#define APP_ADDR_SPACE_0 (16 * SZ_1K)
>
> #define to_keystone_pcie(x) dev_get_drvdata((x)->dev)
>
> struct ks_pcie_of_data {
> + enum dw_pcie_device_mode mode;
> const struct dw_pcie_host_ops *host_ops;
> + const struct dw_pcie_ep_ops *ep_ops;
> unsigned int version;
> };
>
> @@ -877,12 +888,139 @@ static int __init ks_pcie_add_pcie_port(struct keystone_pcie *ks_pcie,
> return 0;
> }
>
> +static u32 ks_pcie_am654_read_dbi2(struct dw_pcie *pci, void __iomem *base,
> + u32 reg, size_t size)
> +{
> + struct keystone_pcie *ks_pcie = to_keystone_pcie(pci);
> + u32 val;
> +
> + ks_pcie_set_dbi_mode(ks_pcie);
> + dw_pcie_read(base + reg, size, &val);
> + ks_pcie_clear_dbi_mode(ks_pcie);
> + return val;
> +}
> +
> +static void ks_pcie_am654_write_dbi2(struct dw_pcie *pci, void __iomem *base,
> + u32 reg, size_t size, u32 val)
> +{
> + struct keystone_pcie *ks_pcie = to_keystone_pcie(pci);
> +
> + ks_pcie_set_dbi_mode(ks_pcie);
> + dw_pcie_write(base + reg, size, val);
> + ks_pcie_clear_dbi_mode(ks_pcie);
> +}
> +
> static const struct dw_pcie_ops ks_pcie_dw_pcie_ops = {
> .start_link = ks_pcie_start_link,
> .stop_link = ks_pcie_stop_link,
> .link_up = ks_pcie_link_up,
> + .read_dbi2 = ks_pcie_am654_read_dbi2,
> + .write_dbi2 = ks_pcie_am654_write_dbi2,
> };
>
> +static void ks_pcie_am654_ep_init(struct dw_pcie_ep *ep)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + int flags;
> +
> + ep->page_size = AM654_WIN_SIZE;
> + flags = PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_32;
> + dw_pcie_writel_dbi2(pci, PCI_BASE_ADDRESS_0, APP_ADDR_SPACE_0 - 1);
> + dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, flags);
> +}
> +
> +static void ks_pcie_am654_raise_legacy_irq(struct keystone_pcie *ks_pcie)
> +{
> + struct dw_pcie *pci = ks_pcie->pci;
> + u8 int_pin;
> +
> + int_pin = dw_pcie_readb_dbi(pci, PCI_INTERRUPT_PIN);
> + if (int_pin == 0 || int_pin > 4)
> + return;
> +
> + ks_pcie_app_writel(ks_pcie, PCIE_LEGACY_IRQ_ENABLE_SET(int_pin),
> + INT_ENABLE);
> + ks_pcie_app_writel(ks_pcie, PCIE_EP_IRQ_SET, INT_ENABLE);
> + mdelay(1);
> + ks_pcie_app_writel(ks_pcie, PCIE_EP_IRQ_CLR, INT_ENABLE);
> + ks_pcie_app_writel(ks_pcie, PCIE_LEGACY_IRQ_ENABLE_CLR(int_pin),
> + INT_ENABLE);
> +}
> +
> +static int ks_pcie_am654_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> + enum pci_epc_irq_type type,
> + u16 interrupt_num)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + struct keystone_pcie *ks_pcie = to_keystone_pcie(pci);
> +
> + switch (type) {
> + case PCI_EPC_IRQ_LEGACY:
> + ks_pcie_am654_raise_legacy_irq(ks_pcie);
> + break;
> + case PCI_EPC_IRQ_MSI:
> + dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
> + break;
> + default:
> + dev_err(pci->dev, "UNKNOWN IRQ type\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static const struct pci_epc_features ks_pcie_am654_epc_features = {
> + .linkup_notifier = false,
> + .msi_capable = true,
> + .msix_capable = false,
> + .reserved_bar = 1 << BAR_0 | 1 << BAR_1,
> + .bar_fixed_64bit = 1 << BAR_0,
> + .bar_fixed_size[2] = SZ_1M,
> + .bar_fixed_size[3] = SZ_64K,
> + .bar_fixed_size[4] = 256,
> + .bar_fixed_size[5] = SZ_1M,
> + .align = SZ_1M,
> +};
> +
> +static const struct pci_epc_features*
> +ks_pcie_am654_get_features(struct dw_pcie_ep *ep)
> +{
> + return &ks_pcie_am654_epc_features;
> +}
> +
> +static const struct dw_pcie_ep_ops ks_pcie_am654_ep_ops = {
> + .ep_init = ks_pcie_am654_ep_init,
> + .raise_irq = ks_pcie_am654_raise_irq,
> + .get_features = &ks_pcie_am654_get_features,
> +};
> +
> +static int __init ks_pcie_add_pcie_ep(struct keystone_pcie *ks_pcie,
> + struct platform_device *pdev)
> +{
> + int ret;
> + struct dw_pcie_ep *ep;
> + struct resource *res;
> + struct device *dev = &pdev->dev;
> + struct dw_pcie *pci = ks_pcie->pci;
> +
> + ep = &pci->ep;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
> + if (!res)
> + return -EINVAL;
> +
> + ep->phys_base = res->start;
> + ep->addr_size = resource_size(res);
> +
> + ret = dw_pcie_ep_init(ep);
> + if (ret) {
> + dev_err(dev, "failed to initialize endpoint\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static void ks_pcie_disable_phy(struct keystone_pcie *ks_pcie)
> {
> int num_lanes = ks_pcie->num_lanes;
> @@ -950,7 +1088,8 @@ static int ks_pcie_set_mode(struct device *dev)
> return 0;
> }
>
> -static int ks_pcie_am654_set_mode(struct device *dev)
> +static int ks_pcie_am654_set_mode(struct device *dev,
> + enum dw_pcie_device_mode mode)
> {
> struct device_node *np = dev->of_node;
> struct regmap *syscon;
> @@ -963,7 +1102,18 @@ static int ks_pcie_am654_set_mode(struct device *dev)
> return 0;
>
> mask = AM654_PCIE_DEV_TYPE_MASK;
> - val = RC;
> +
> + switch (mode) {
> + case DW_PCIE_RC_TYPE:
> + val = RC;
> + break;
> + case DW_PCIE_EP_TYPE:
> + val = EP;
> + break;
> + default:
> + dev_err(dev, "INVALID device type %d\n", mode);
> + return -EINVAL;
> + }
>
> ret = regmap_update_bits(syscon, 0, mask, val);
> if (ret) {
> @@ -1006,6 +1156,13 @@ static const struct ks_pcie_of_data ks_pcie_rc_of_data = {
>
> static const struct ks_pcie_of_data ks_pcie_am654_rc_of_data = {
> .host_ops = &ks_pcie_am654_host_ops,
> + .mode = DW_PCIE_RC_TYPE,
> + .version = 0x490A,
> +};
> +
> +static const struct ks_pcie_of_data ks_pcie_am654_ep_of_data = {
> + .ep_ops = &ks_pcie_am654_ep_ops,
> + .mode = DW_PCIE_EP_TYPE,
> .version = 0x490A,
> };
>
> @@ -1019,16 +1176,22 @@ static const struct of_device_id ks_pcie_of_match[] = {
> .data = &ks_pcie_am654_rc_of_data,
> .compatible = "ti,am654-pcie-rc",
> },
> + {
> + .data = &ks_pcie_am654_ep_of_data,
> + .compatible = "ti,am654-pcie-ep",
> + },
> { },
> };
>
> static int __init ks_pcie_probe(struct platform_device *pdev)
> {
> const struct dw_pcie_host_ops *host_ops;
> + const struct dw_pcie_ep_ops *ep_ops;
> struct device *dev = &pdev->dev;
> struct device_node *np = dev->of_node;
> const struct ks_pcie_of_data *data;
> const struct of_device_id *match;
> + enum dw_pcie_device_mode mode;
> struct dw_pcie *pci;
> struct keystone_pcie *ks_pcie;
> struct device_link **link;
> @@ -1053,6 +1216,8 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
>
> version = data->version;
> host_ops = data->host_ops;
> + ep_ops = data->ep_ops;
> + mode = data->mode;
>
> ks_pcie = devm_kzalloc(dev, sizeof(*ks_pcie), GFP_KERNEL);
> if (!ks_pcie)
> @@ -1078,16 +1243,11 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
> ks_pcie->is_am6 = true;
>
> pci->dbi_base = base;
> + pci->dbi_base2 = base;
> pci->dev = dev;
> pci->ops = &ks_pcie_dw_pcie_ops;
> pci->version = version;
>
> - ret = of_property_read_u32(np, "num-viewport", &num_viewport);
> - if (ret < 0) {
> - dev_err(dev, "unable to read *num-viewport* property\n");
> - return ret;
> - }
> -
> irq = platform_get_irq(pdev, 0);
> if (irq < 0) {
> dev_err(dev, "missing IRQ resource: %d\n", irq);
> @@ -1136,7 +1296,6 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
> ks_pcie->pci = pci;
> ks_pcie->link = link;
> ks_pcie->num_lanes = num_lanes;
> - ks_pcie->num_viewport = num_viewport;
> ks_pcie->phy = phy;
>
> gpiod = devm_gpiod_get_optional(dev, "reset",
> @@ -1172,7 +1331,7 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
>
> pci->atu_base = atu_base;
>
> - ret = ks_pcie_am654_set_mode(dev);
> + ret = ks_pcie_am654_set_mode(dev, mode);
> if (ret < 0)
> goto err_get_sync;
> } else {
> @@ -1181,29 +1340,58 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
> goto err_get_sync;
> }
>
> - /*
> - * "Power Sequencing and Reset Signal Timings" table in
> - * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 2.0
> - * indicates PERST# should be deasserted after minimum of 100us
> - * once REFCLK is stable. The REFCLK to the connector in RC
> - * mode is selected while enabling the PHY. So deassert PERST#
> - * after 100 us.
> - */
> - if (gpiod) {
> - usleep_range(100, 200);
> - gpiod_set_value_cansleep(gpiod, 1);
> - }
> -
> link_speed = of_pci_get_max_link_speed(np);
> if (link_speed < 0)
> link_speed = 2;
>
> ks_pcie_set_link_speed(pci, link_speed);
>
> - pci->pp.ops = host_ops;
> - ret = ks_pcie_add_pcie_port(ks_pcie, pdev);
> - if (ret < 0)
> - goto err_get_sync;
> + switch (mode) {
> + case DW_PCIE_RC_TYPE:
> + if (!IS_ENABLED(CONFIG_PCI_KEYSTONE_HOST)) {
> + ret = -ENODEV;
> + goto err_get_sync;
> + }
> +
> + ret = of_property_read_u32(np, "num-viewport", &num_viewport);
> + if (ret < 0) {
> + dev_err(dev, "unable to read *num-viewport* property\n");
> + return ret;
> + }
> +
> + /*
> + * "Power Sequencing and Reset Signal Timings" table in
> + * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 2.0
> + * indicates PERST# should be deasserted after minimum of 100us
> + * once REFCLK is stable. The REFCLK to the connector in RC
> + * mode is selected while enabling the PHY. So deassert PERST#
> + * after 100 us.
> + */
> + if (gpiod) {
> + usleep_range(100, 200);
> + gpiod_set_value_cansleep(gpiod, 1);
> + }
> +
> + ks_pcie->num_viewport = num_viewport;
> + pci->pp.ops = host_ops;
> + ret = ks_pcie_add_pcie_port(ks_pcie, pdev);
> + if (ret < 0)
> + goto err_get_sync;
> + break;
> + case DW_PCIE_EP_TYPE:
> + if (!IS_ENABLED(CONFIG_PCI_KEYSTONE_EP)) {
> + ret = -ENODEV;
> + goto err_get_sync;
> + }
> +
> + pci->ep.ops = ep_ops;
> + ret = ks_pcie_add_pcie_ep(ks_pcie, pdev);
> + if (ret < 0)
> + goto err_get_sync;
> + break;
> + default:
> + dev_err(dev, "INVALID device type %d\n", mode);
> + }
>
> ks_pcie_enable_error_irq(ks_pcie);
>
> --
> 2.17.1
>