[PATCH v3 4/4] PCI: host: pcie-dra7xx: add support for pcie-dra7xx controller

Kishon Vijay Abraham I
2014-07-17T09:02:47Z

Added support for pcie controller in dra7xx. This driver re-uses
the designware core code that is already present in kernel.

Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Mohit Kumar <mohit.kumar@st.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
---
MAINTAINERS | 8 +
drivers/pci/host/Kconfig | 10 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-dra7xx.c | 458 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 477 insertions(+)
create mode 100644 drivers/pci/host/pci-dra7xx.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 134483f..fdd34d1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6796,6 +6796,14 @@ S: Supported
F: Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt
F: drivers/pci/host/pci-tegra.c

+PCI DRIVER FOR TI DRA7XX
+M: Kishon Vijay Abraham I <kishon@ti.com>
+L: linux-omap@vger.kernel.org
+L: linux-pci@vger.kernel.org
+S: Supported
+F: Documentation/devicetree/bindings/pci/ti-pci.txt
+F: drivers/pci/host/pci-dra7xx.c
+
PCI DRIVER FOR RENESAS R-CAR
M: Simon Horman <horms@verge.net.au>
L: linux-pci@vger.kernel.org
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 21df477..22117b0 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -1,6 +1,16 @@
menu "PCI host controller drivers"
depends on PCI

+config PCI_DRA7XX
+ bool "TI DRA7xx PCIe controller"
+ select PCIE_DW
+ depends on OF && HAS_IOMEM && TI_PIPE3
+ help
+ Enables support for the PCIE controller present in DRA7xx SoC. There
+ are two instances of PCIE controller in DRA7xx. This controller can
+ act both as EP and RC. This reuses the same Designware core as used
+ by other SoCs.
+
config PCI_MVEBU
bool "Marvell EBU PCIe controller"
depends on ARCH_MVEBU || ARCH_DOVE || ARCH_KIRKWOOD
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 611ba4b..c42844d 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_PCIE_DW) += pcie-designware.o
+obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
obj-$(CONFIG_PCI_IMX6) += pci-imx6.o
obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
new file mode 100644
index 0000000..52b34fe
--- /dev/null
+++ b/drivers/pci/host/pci-dra7xx.c
@@ -0,0 +1,458 @@
+/*
+ * pcie-dra7xx - PCIe controller driver for TI DRA7xx SoCs
+ *
+ * Copyright (C) 2013-2014 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Authors: Kishon Vijay Abraham I <kishon@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/resource.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+
+/* PCIe controller wrapper DRA7XX configuration registers */
+
+#define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN 0x0024
+#define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN 0x0028
+#define ERR_SYS BIT(0)
+#define ERR_FATAL BIT(1)
+#define ERR_NONFATAL BIT(2)
+#define ERR_COR BIT(3)
+#define ERR_AXI BIT(4)
+#define ERR_ECRC BIT(5)
+#define PME_TURN_OFF BIT(8)
+#define PME_TO_ACK BIT(9)
+#define PM_PME BIT(10)
+#define LINK_REQ_RST BIT(11)
+#define LINK_UP_EVT BIT(12)
+#define CFG_BME_EVT BIT(13)
+#define CFG_MSE_EVT BIT(14)
+#define INTERRUPTS (ERR_SYS | ERR_FATAL | ERR_NONFATAL | ERR_COR | ERR_AXI | \
+ ERR_ECRC | PME_TURN_OFF | PME_TO_ACK | PM_PME | \
+ LINK_REQ_RST | LINK_UP_EVT | CFG_BME_EVT | CFG_MSE_EVT)
+
+#define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI 0x0034
+#define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI 0x0038
+#define INTA BIT(0)
+#define INTB BIT(1)
+#define INTC BIT(2)
+#define INTD BIT(3)
+#define MSI BIT(4)
+#define LEG_EP_INTERRUPTS (INTA | INTB | INTC | INTD)
+
+#define PCIECTRL_DRA7XX_CONF_DEVICE_CMD 0x0104
+#define LTSSM_EN 0x1
+
+#define PCIECTRL_DRA7XX_CONF_PHY_CS 0x010C
+#define LINK_UP BIT(16)
+
+struct dra7xx_pcie {
+ void __iomem *base;
+ struct phy **phy;
+ int phy_count;
+ struct device *dev;
+ struct pcie_port pp;
+};
+
+#define to_dra7xx_pcie(x) container_of((x), struct dra7xx_pcie, pp)
+
+static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
+{
+ return readl(pcie->base + offset);
+}
+
+static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset,
+ u32 value)
+{
+ writel(value, pcie->base + offset);
+}
+
+static int dra7xx_pcie_link_up(struct pcie_port *pp)
+{
+ struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
+ u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
+
+ return !!(reg & LINK_UP);
+}
+
+static int dra7xx_pcie_establish_link(struct pcie_port *pp)
+{
+ u32 reg;
+ unsigned int retries = 1000;
+ struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
+
+ if (dw_pcie_link_up(pp)) {
+ dev_err(pp->dev, "link is already up\n");
+ return 0;
+ }
+
+ reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
+ reg |= LTSSM_EN;
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
+
+ while (retries--) {
+ reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);
+ if (reg & LINK_UP)
+ break;
+ usleep_range(10, 20);
+ }
+
+ if (retries == 0) {
+ dev_err(pp->dev, "link is not up\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
+{
+ struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
+
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
+ ~INTERRUPTS);
+ dra7xx_pcie_writel(dra7xx,
+ PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
+ ~LEG_EP_INTERRUPTS & ~MSI);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ dra7xx_pcie_writel(dra7xx,
+ PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
+ else
+ dra7xx_pcie_writel(dra7xx,
+ PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
+ LEG_EP_INTERRUPTS);
+}
+
+static void dra7xx_pcie_host_init(struct pcie_port *pp)
+{
+ dw_pcie_setup_rc(pp);
+ dra7xx_pcie_establish_link(pp);
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ dw_pcie_msi_init(pp);
+ dra7xx_pcie_enable_interrupts(pp);
+}
+
+static struct pcie_host_ops dra7xx_pcie_host_ops = {
+ .link_up = dra7xx_pcie_link_up,
+ .host_init = dra7xx_pcie_host_init,
+};
+
+static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
+ irq_set_chip_data(irq, domain->host_data);
+ set_irq_flags(irq, IRQF_VALID);
+
+ return 0;
+}
+
+static const struct irq_domain_ops intx_domain_ops = {
+ .map = dra7xx_pcie_intx_map,
+};
+
+static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
+{
+ struct device *dev = pp->dev;
+ struct device_node *node = dev->of_node;
+ struct device_node *pcie_intc_node = of_get_next_child(node, NULL);
+
+ if (!pcie_intc_node) {
+ dev_err(dev, "No PCIe Intc node found\n");
+ return PTR_ERR(pcie_intc_node);
+ }
+
+ pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
+ &intx_domain_ops, pp);
+ if (!pp->irq_domain) {
+ dev_err(dev, "Failed to get a INTx IRQ domain\n");
+ return PTR_ERR(pp->irq_domain);
+ }
+
+ return 0;
+}
+
+static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+ struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
+ u32 reg;
+
+ reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);
+
+ switch (reg) {
+ case MSI:
+ dw_handle_msi_irq(pp);
+ break;
+ case INTA:
+ case INTB:
+ case INTC:
+ case INTD:
+ generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
+ break;
+ }
+
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);
+
+ return IRQ_HANDLED;
+}
+
+
+static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
+{
+ struct dra7xx_pcie *dra7xx = arg;
+ u32 reg;
+
+ reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);
+
+ if (reg & ERR_SYS)
+ dev_dbg(dra7xx->dev, "System Error\n");
+
+ if (reg & ERR_FATAL)
+ dev_dbg(dra7xx->dev, "Fatal Error\n");
+
+ if (reg & ERR_NONFATAL)
+ dev_dbg(dra7xx->dev, "Non Fatal Error\n");
+
+ if (reg & ERR_COR)
+ dev_dbg(dra7xx->dev, "Correctable Error\n");
+
+ if (reg & ERR_AXI)
+ dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");
+
+ if (reg & ERR_ECRC)
+ dev_dbg(dra7xx->dev, "ECRC Error\n");
+
+ if (reg & PME_TURN_OFF)
+ dev_dbg(dra7xx->dev,
+ "Power Management Event Turn-Off message received\n");
+
+ if (reg & PME_TO_ACK)
+ dev_dbg(dra7xx->dev,
+ "Power Management Turn-Off Ack message received\n");
+
+ if (reg & PM_PME)
+ dev_dbg(dra7xx->dev,
+ "PM Power Management Event message received\n");
+
+ if (reg & LINK_REQ_RST)
+ dev_dbg(dra7xx->dev, "Link Request Reset\n");
+
+ if (reg & LINK_UP_EVT)
+ dev_dbg(dra7xx->dev, "Link-up state change\n");
+
+ if (reg & CFG_BME_EVT)
+ dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");
+
+ if (reg & CFG_MSE_EVT)
+ dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");
+
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);
+
+ return IRQ_HANDLED;
+}
+
+static int add_pcie_port(struct dra7xx_pcie *dra7xx,
+ struct platform_device *pdev)
+{
+ int ret;
+ struct pcie_port *pp;
+ struct resource *res;
+ struct device *dev = &pdev->dev;
+
+ pp = &dra7xx->pp;
+ pp->dev = dev;
+ pp->ops = &dra7xx_pcie_host_ops;
+
+ pp->irq = platform_get_irq(pdev, 1);
+ if (pp->irq < 0) {
+ dev_err(dev, "missing IRQ resource\n");
+ return -EINVAL;
+ }
+
+ ret = devm_request_irq(&pdev->dev, pp->irq,
+ dra7xx_pcie_msi_irq_handler, IRQF_SHARED,
+ "dra7-pcie-msi", pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request irq\n");
+ return ret;
+ }
+
+ if (!IS_ENABLED(CONFIG_PCI_MSI)) {
+ ret = dra7xx_pcie_init_irq_domain(pp);
+ if (ret < 0)
+ return ret;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
+ pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!pp->dbi_base)
+ return -ENOMEM;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(dra7xx->dev, "failed to initialize host\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int __init dra7xx_pcie_probe(struct platform_device *pdev)
+{
+ u32 reg;
+ int ret;
+ int irq;
+ int i;
+ int phy_count;
+ struct phy **phy;
+ void __iomem *base;
+ struct resource *res;
+ struct dra7xx_pcie *dra7xx;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ char name[10];
+
+ dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
+ if (!dra7xx)
+ return -ENOMEM;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(dev, "missing IRQ resource\n");
+ return -EINVAL;
+ }
+
+ ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
+ IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
+ if (ret) {
+ dev_err(dev, "failed to request irq\n");
+ return ret;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
+ base = devm_ioremap_nocache(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ phy_count = of_property_count_strings(np, "phy-names");
+ if (phy_count < 0) {
+ dev_err(dev, "unable to find the strings\n");
+ return phy_count;
+ }
+
+ phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
+ if (!phy)
+ return -ENOMEM;
+
+ for (i = 0; i < phy_count; i++) {
+ snprintf(name, sizeof(name), "pcie-phy%d", i);
+ phy[i] = devm_phy_get(dev, name);
+ if (IS_ERR(phy[i]))
+ return PTR_ERR(phy[i]);
+
+ ret = phy_init(phy[i]);
+ if (ret < 0)
+ goto err_phy;
+
+ ret = phy_power_on(phy[i]);
+ if (ret < 0) {
+ phy_exit(phy[i]);
+ goto err_phy;
+ }
+ }
+
+ dra7xx->base = base;
+ dra7xx->phy = phy;
+ dra7xx->dev = dev;
+ dra7xx->phy_count = phy_count;
+
+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (IS_ERR_VALUE(ret)) {
+ dev_err(dev, "pm_runtime_get_sync failed\n");
+ goto err_phy;
+ }
+
+ reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
+ reg &= ~LTSSM_EN;
+ dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
+
+ platform_set_drvdata(pdev, dra7xx);
+
+ ret = add_pcie_port(dra7xx, pdev);
+ if (ret < 0)
+ goto err_add_port;
+
+ return 0;
+
+err_add_port:
+ pm_runtime_put(dev);
+ pm_runtime_disable(dev);
+
+err_phy:
+ while (--i >= 0) {
+ phy_power_off(phy[i]);
+ phy_exit(phy[i]);
+ }
+
+ return ret;
+}
+
+static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
+{
+ struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
+ struct pcie_port *pp = &dra7xx->pp;
+ struct device *dev = &pdev->dev;
+ int count = dra7xx->phy_count;
+
+ if (pp->irq_domain)
+ irq_domain_remove(pp->irq_domain);
+ pm_runtime_put(dev);
+ pm_runtime_disable(dev);
+ while (count--) {
+ phy_power_off(dra7xx->phy[count]);
+ phy_exit(dra7xx->phy[count]);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_dra7xx_pcie_match[] = {
+ { .compatible = "ti,dra7-pcie", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);
+
+static struct platform_driver dra7xx_pcie_driver = {
+ .remove = __exit_p(dra7xx_pcie_remove),
+ .driver = {
+ .name = "dra7-pcie",
+ .owner = THIS_MODULE,
+ .of_match_table = of_dra7xx_pcie_match,
+ },
+};
+
+module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);
+
+MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
+MODULE_DESCRIPTION("TI PCIe controller driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5