[PATCH v2 22/26] PCI: keystone: Add support for PCIe EP in AM654x Platforms

From: Kishon Vijay Abraham I
Date: Mon Mar 25 2019 - 04:38:07 EST


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(-)

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