[PATCH v5 14/18] PCI: dwc: artpec6: Add support for endpoint mode

Niklas Cassel
2017-11-20T13:35:12Z

The PCIe controller integrated in ARTPEC-6 SoCs is capable of operating in
endpoint mode. Add endpoint mode support to the artpec6 driver.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
---
drivers/pci/dwc/Kconfig | 23 +++++--
drivers/pci/dwc/pcie-artpec6.c | 152 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 164 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/dwc/Kconfig b/drivers/pci/dwc/Kconfig
index 3954353e3e2e..0fb96c7754de 100644
--- a/drivers/pci/dwc/Kconfig
+++ b/drivers/pci/dwc/Kconfig
@@ -148,15 +148,28 @@ config PCIE_ARMADA_8K
DesignWare core functions to implement the driver.

config PCIE_ARTPEC6
- bool "Axis ARTPEC-6 PCIe controller"
- depends on PCI
+ bool
+
+config PCIE_ARTPEC6_HOST
+ bool "Axis ARTPEC-6 PCIe controller Host Mode"
depends on MACH_ARTPEC6
- depends on PCI_MSI_IRQ_DOMAIN
+ depends on PCI && PCI_MSI_IRQ_DOMAIN
select PCIEPORTBUS
select PCIE_DW_HOST
+ select PCIE_ARTPEC6
+ help
+ Enables support for the PCIe controller in the ARTPEC-6 SoC to work in
+ host mode. This uses the DesignWare core.
+
+config PCIE_ARTPEC6_EP
+ bool "Axis ARTPEC-6 PCIe controller Endpoint Mode"
+ depends on MACH_ARTPEC6
+ depends on PCI_ENDPOINT
+ select PCIE_DW_EP
+ select PCIE_ARTPEC6
help
- Say Y here to enable PCIe controller support on Axis ARTPEC-6
- SoCs. This PCIe controller uses the DesignWare core.
+ Enables support for the PCIe controller in the ARTPEC-6 SoC to work in
+ endpoint mode. This uses the DesignWare core.

config PCIE_KIRIN
depends on OF && ARM64
diff --git a/drivers/pci/dwc/pcie-artpec6.c b/drivers/pci/dwc/pcie-artpec6.c
index b2783b475c2a..e7de4e4649eb 100644
--- a/drivers/pci/dwc/pcie-artpec6.c
+++ b/drivers/pci/dwc/pcie-artpec6.c
@@ -13,6 +13,7 @@
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/of_device.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/resource.h>
@@ -30,8 +31,15 @@ struct artpec6_pcie {
struct dw_pcie *pci;
struct regmap *regmap; /* DT axis,syscon-pcie */
void __iomem *phy_base; /* DT phy */
+ enum dw_pcie_device_mode mode;
};

+struct artpec_pcie_of_data {
+ enum dw_pcie_device_mode mode;
+};
+
+static const struct of_device_id artpec6_pcie_of_match[];
+
/* PCIe Port Logic registers (memory-mapped) */
#define PL_OFFSET 0x700

@@ -40,6 +48,7 @@ struct artpec6_pcie {
#define PCIECFG_DBG_OEN BIT(24)
#define PCIECFG_CORE_RESET_REQ BIT(21)
#define PCIECFG_LTSSM_ENABLE BIT(20)
+#define PCIECFG_DEVICE_TYPE_MASK GENMASK(19, 16)
#define PCIECFG_CLKREQ_B BIT(11)
#define PCIECFG_REFCLK_ENABLE BIT(10)
#define PCIECFG_PLL_ENABLE BIT(9)
@@ -90,6 +99,22 @@ static int artpec6_pcie_establish_link(struct dw_pcie *pci)
return 0;
}

+static void artpec6_pcie_stop_link(struct dw_pcie *pci)
+{
+ struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci);
+ u32 val;
+
+ val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+ val &= ~PCIECFG_LTSSM_ENABLE;
+ artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+}
+
+static const struct dw_pcie_ops dw_pcie_ops = {
+ .cpu_addr_fixup = artpec6_pcie_cpu_addr_fixup,
+ .start_link = artpec6_pcie_establish_link,
+ .stop_link = artpec6_pcie_stop_link,
+};
+
static void artpec6_pcie_init_phy(struct artpec6_pcie *artpec6_pcie)
{
u32 val;
@@ -230,10 +255,76 @@ static int artpec6_add_pcie_port(struct artpec6_pcie *artpec6_pcie,
return 0;
}

-static const struct dw_pcie_ops dw_pcie_ops = {
- .cpu_addr_fixup = artpec6_pcie_cpu_addr_fixup,
+static void artpec6_pcie_ep_init(struct dw_pcie_ep *ep)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci);
+ enum pci_barno bar;
+
+ artpec6_pcie_assert_core_reset(artpec6_pcie);
+ artpec6_pcie_init_phy(artpec6_pcie);
+ artpec6_pcie_deassert_core_reset(artpec6_pcie);
+
+ for (bar = BAR_0; bar <= BAR_5; bar++)
+ dw_pcie_ep_reset_bar(pci, bar);
+}
+
+static int artpec6_pcie_raise_irq(struct dw_pcie_ep *ep,
+ enum pci_epc_irq_type type, u8 interrupt_num)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ switch (type) {
+ case PCI_EPC_IRQ_LEGACY:
+ dev_err(pci->dev, "EP cannot trigger legacy IRQs\n");
+ return -EINVAL;
+ case PCI_EPC_IRQ_MSI:
+ return dw_pcie_ep_raise_msi_irq(ep, interrupt_num);
+ default:
+ dev_err(pci->dev, "UNKNOWN IRQ type\n");
+ }
+
+ return 0;
+}
+
+static struct dw_pcie_ep_ops pcie_ep_ops = {
+ .ep_init = artpec6_pcie_ep_init,
+ .raise_irq = artpec6_pcie_raise_irq,
};

+static int artpec6_add_pcie_ep(struct artpec6_pcie *artpec6_pcie,
+ struct platform_device *pdev)
+{
+ int ret;
+ struct dw_pcie_ep *ep;
+ struct resource *res;
+ struct device *dev = &pdev->dev;
+ struct dw_pcie *pci = artpec6_pcie->pci;
+
+ ep = &pci->ep;
+ ep->ops = &pcie_ep_ops;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi2");
+ pci->dbi_base2 = devm_ioremap(dev, res->start, resource_size(res));
+ if (IS_ERR(pci->dbi_base2))
+ return PTR_ERR(pci->dbi_base2);
+
+ 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 int artpec6_pcie_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -242,6 +333,16 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
struct resource *dbi_base;
struct resource *phy_base;
int ret;
+ const struct of_device_id *match;
+ const struct artpec_pcie_of_data *data;
+ enum dw_pcie_device_mode mode;
+
+ match = of_match_device(artpec6_pcie_of_match, dev);
+ if (!match)
+ return -EINVAL;
+
+ data = (struct artpec_pcie_of_data *)match->data;
+ mode = (enum dw_pcie_device_mode)data->mode;

artpec6_pcie = devm_kzalloc(dev, sizeof(*artpec6_pcie), GFP_KERNEL);
if (!artpec6_pcie)
@@ -255,6 +356,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev)
pci->ops = &dw_pcie_ops;

artpec6_pcie->pci = pci;
+ artpec6_pcie->mode = mode;

dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
@@ -274,15 +376,53 @@ static int artpec6_pcie_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, artpec6_pcie);

- ret = artpec6_add_pcie_port(artpec6_pcie, pdev);
- if (ret < 0)
- return ret;
+ switch (artpec6_pcie->mode) {
+ case DW_PCIE_RC_TYPE:
+ if (!IS_ENABLED(CONFIG_PCIE_ARTPEC6_HOST))
+ return -ENODEV;
+
+ ret = artpec6_add_pcie_port(artpec6_pcie, pdev);
+ if (ret < 0)
+ return ret;
+ break;
+ case DW_PCIE_EP_TYPE: {
+ u32 val;
+
+ if (!IS_ENABLED(CONFIG_PCIE_ARTPEC6_EP))
+ return -ENODEV;
+
+ val = artpec6_pcie_readl(artpec6_pcie, PCIECFG);
+ val &= ~PCIECFG_DEVICE_TYPE_MASK;
+ artpec6_pcie_writel(artpec6_pcie, PCIECFG, val);
+ ret = artpec6_add_pcie_ep(artpec6_pcie, pdev);
+ if (ret < 0)
+ return ret;
+ break;
+ }
+ default:
+ dev_err(dev, "INVALID device type %d\n", artpec6_pcie->mode);
+ }

return 0;
}

+static const struct artpec_pcie_of_data artpec6_pcie_rc_of_data = {
+ .mode = DW_PCIE_RC_TYPE,
+};
+
+static const struct artpec_pcie_of_data artpec6_pcie_ep_of_data = {
+ .mode = DW_PCIE_EP_TYPE,
+};
+
static const struct of_device_id artpec6_pcie_of_match[] = {
- { .compatible = "axis,artpec6-pcie", },
+ {
+ .compatible = "axis,artpec6-pcie",
+ .data = &artpec6_pcie_rc_of_data,
+ },
+ {
+ .compatible = "axis,artpec6-pcie-ep",
+ .data = &artpec6_pcie_ep_of_data,
+ },
{},
};

--
2.14.2