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

From: Kishon Vijay Abraham I
Date: Fri Apr 26 2019 - 08:43:34 EST


Hi Lorenzo,

On 26/04/19 3:10 PM, Lorenzo Pieralisi wrote:
> 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@xxxxxx>
>> ---
>> 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.

Looks like I've missed adding the dt-binding Documentation patch. I'll send a
patch to add the EP mode dt-binding Documentation.

Thanks
Kishon
>
> 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
>>