[RFC PATCH 4/6] PCI: exynos5433: Add new exynos pci host controller for Exynos5433

From: Jaehoon Chung
Date: Mon Dec 26 2016 - 00:20:56 EST


Exynos5433 supports the PCIe.
This patch adds new pci-exynos5433.c file for Exynos ARM64.

Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
---
drivers/pci/host/Kconfig | 9 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-exynos5433.c | 338 ++++++++++++++++++++++++++++++++++++++
3 files changed, 348 insertions(+)
create mode 100644 drivers/pci/host/pci-exynos5433.c

diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index d7e7c0a..3d77d0b 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -60,6 +60,15 @@ config PCI_EXYNOS
select PCIEPORTBUS
select PCIE_DW

+config PCI_EXYNOS5433
+ bool "Samsung Exynos5433 PCIe controller"
+ depends on ARCH_EXYNOS && ARM64
+ depends on PCI_MSI_IRQ_DOMAIN
+ select PCIEPORTBUS
+ select PCIE_DW
+ help
+ If you want support for Exynos5433 PCIe host controller, say Y.
+
config PCI_IMX6
bool "Freescale i.MX6 PCIe controller"
depends on SOC_IMX6Q
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 084cb49..2168de2 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_PCIE_DW) += pcie-designware.o
obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o
obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
+obj-$(CONFIG_PCI_EXYNOS5433) += pci-exynos5433.o
obj-$(CONFIG_PCI_IMX6) += pci-imx6.o
obj-$(CONFIG_PCI_HYPERV) += pci-hyperv.o
obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
diff --git a/drivers/pci/host/pci-exynos5433.c b/drivers/pci/host/pci-exynos5433.c
new file mode 100644
index 0000000..ff254ca
--- /dev/null
+++ b/drivers/pci/host/pci-exynos5433.c
@@ -0,0 +1,338 @@
+/*
+ * PCIe host controller driver for Samsung EXYNOS5433 SoCs
+ *
+ * Copyright (C) 2016 Samsung Electronics Co., Ltd.
+ * http://www.samsung.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/clk.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+#include <linux/mfd/syscon.h>
+#include <linux/phy/phy.h>
+
+#include "pcie-designware.h"
+
+#define to_exynos_pcie(x) container_of(x, struct exynos_pcie, pp)
+
+/* Pcie structure for Exynos specific data */
+struct exynos_pcie {
+ void __iomem *elbi_base;
+ struct clk *clk;
+ struct clk *bus_clk;
+ struct pcie_port pp;
+ struct phy *phy;
+};
+
+/* PCIe ELBI registers */
+#define PCIE_IRQ_PULSE 0x000
+#define IRQ_INTA_ASSERT BIT(0)
+#define IRQ_INTB_ASSERT BIT(2)
+#define IRQ_INTC_ASSERT BIT(4)
+#define IRQ_INTD_ASSERT BIT(6)
+#define IRQ_INTX_ASSERT (IRQ_INTA_ASSERT | IRQ_INTB_ASSERT | \
+ IRQ_INTC_ASSERT | IRQ_INTD_ASSERT)
+#define PCIE_IRQ_EN_PULSE 0x00c
+#define PCIE_IRQ_EN_LEVEL 0x010
+#define PCIE_SW_WAKE 0x018
+#define PCIE_BUS_EN BIT(1)
+#define PCIE_APP_LTSSM_ENABLE 0x02c
+#define PCIE_ELBI_LTSSM_ENABLE 0x1
+#define PCIE_ELBI_DEBUG_L 0x074
+#define PCIE_ELBI_XMLH_LINK_UP BIT(4)
+#define PCIE_ELBI_SLV_AWMISC 0x11c
+#define PCIE_ELBI_SLV_ARMISC 0x120
+#define PCIE_ELBI_SLV_DBI_ENABLE BIT(21)
+
+/* DBI register */
+#define PCIE_MISC_CONTROL_1_OFF 0x8BC
+#define DBI_RO_WR_EN BIT(0)
+
+static inline void exynos_pcie_writel(void __iomem *base, u32 val, u32 offset)
+{
+ writel(val, base + offset);
+}
+
+static inline u32 exynos_pcie_readl(void __iomem *base, u32 offset)
+{
+ return readl(base + offset);
+}
+
+static void exynos_pcie_clear_irq_pulse(struct exynos_pcie *ep)
+{
+ u32 val;
+
+ val = exynos_pcie_readl(ep->elbi_base, PCIE_IRQ_PULSE);
+ val &= ~IRQ_INTX_ASSERT;
+ exynos_pcie_writel(ep->elbi_base, val, PCIE_IRQ_PULSE);
+}
+
+static void exynos_pcie_enable_irq_pulse(struct exynos_pcie *ep)
+{
+ exynos_pcie_writel(ep->elbi_base, IRQ_INTX_ASSERT, PCIE_IRQ_EN_PULSE);
+
+ /* Clear PCIE_IRQ_EN_LEVEL register */
+ exynos_pcie_writel(ep->elbi_base, 0, PCIE_IRQ_EN_LEVEL);
+}
+
+static irqreturn_t exynos_pcie_irq_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+ struct exynos_pcie *ep = to_exynos_pcie(pp);
+
+ exynos_pcie_clear_irq_pulse(ep);
+
+ return IRQ_HANDLED;
+}
+
+static void exynos_pcie_sideband_dbi_w_mode(struct exynos_pcie *ep, bool on)
+{
+ u32 val;
+
+ val = exynos_pcie_readl(ep->elbi_base, PCIE_ELBI_SLV_AWMISC);
+ if (on)
+ val |= PCIE_ELBI_SLV_DBI_ENABLE;
+ else
+ val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+ exynos_pcie_writel(ep->elbi_base, val, PCIE_ELBI_SLV_AWMISC);
+}
+
+static void exynos_pcie_sideband_dbi_r_mode(struct exynos_pcie *ep, bool on)
+{
+ u32 val;
+
+ val = exynos_pcie_readl(ep->elbi_base, PCIE_ELBI_SLV_ARMISC);
+ if (on)
+ val |= PCIE_ELBI_SLV_DBI_ENABLE;
+ else
+ val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+ exynos_pcie_writel(ep->elbi_base, val, PCIE_ELBI_SLV_ARMISC);
+}
+
+static int exynos_pcie_establish_link(struct exynos_pcie *ep)
+{
+ struct pcie_port *pp = &ep->pp;
+ u32 val;
+
+ if (dw_pcie_link_up(pp)) {
+ dev_info(pp->dev, "Link already up\n");
+ return 0;
+ }
+
+ phy_power_on(ep->phy);
+
+ /* Exynos Pcie assert PHY reset and init */
+ phy_init(ep->phy);
+
+ val = exynos_pcie_readl(ep->elbi_base, PCIE_SW_WAKE);
+ val &= ~PCIE_BUS_EN;
+ exynos_pcie_writel(ep->elbi_base, val, PCIE_SW_WAKE);
+
+ /*
+ * Enable DBI_RO_WR_EN bit.
+ * - When set to 1, some RO and HWinit bits are wriatble from
+ * the local application through the DBI.
+ */
+ dw_pcie_writel_rc(pp, PCIE_MISC_CONTROL_1_OFF, DBI_RO_WR_EN);
+
+ /* Setup root complex */
+ dw_pcie_setup_rc(pp);
+
+ /* assert LTSSM enable */
+ exynos_pcie_writel(ep->elbi_base, PCIE_ELBI_LTSSM_ENABLE,
+ PCIE_APP_LTSSM_ENABLE);
+
+ return dw_pcie_wait_for_link(pp);
+}
+
+
+static int exynos_pcie_link_up(struct pcie_port *pp)
+{
+ struct exynos_pcie *ep = to_exynos_pcie(pp);
+ u32 val;
+
+ /* Check the Receive Transaction Layer Handler */
+ val = exynos_pcie_readl(ep->elbi_base, PCIE_ELBI_DEBUG_L);
+
+ return (val & PCIE_ELBI_XMLH_LINK_UP);
+}
+
+static void exynos_pcie_host_init(struct pcie_port *pp)
+{
+ struct exynos_pcie *ep = to_exynos_pcie(pp);
+
+ exynos_pcie_enable_irq_pulse(ep);
+ exynos_pcie_establish_link(ep);
+}
+
+static u32 exynos_pcie_readl_rc(struct pcie_port *pp, u32 reg)
+{
+ struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+ u32 val;
+
+ exynos_pcie_sideband_dbi_r_mode(exynos_pcie, true);
+ val = readl(pp->dbi_base + reg);
+ exynos_pcie_sideband_dbi_r_mode(exynos_pcie, false);
+ return val;
+}
+
+static void exynos_pcie_writel_rc(struct pcie_port *pp, u32 reg, u32 val)
+{
+ struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+
+ exynos_pcie_sideband_dbi_w_mode(exynos_pcie, true);
+ writel(val, pp->dbi_base + reg);
+ exynos_pcie_sideband_dbi_w_mode(exynos_pcie, false);
+}
+
+static int exynos_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
+ u32 *val)
+{
+ struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+ int ret;
+
+ exynos_pcie_sideband_dbi_r_mode(exynos_pcie, true);
+ ret = dw_pcie_cfg_read(pp->dbi_base + where, size, val);
+ exynos_pcie_sideband_dbi_r_mode(exynos_pcie, false);
+ return ret;
+}
+
+static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
+ u32 val)
+{
+ struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+ int ret;
+
+ exynos_pcie_sideband_dbi_w_mode(exynos_pcie, true);
+ ret = dw_pcie_cfg_write(pp->dbi_base + where, size, val);
+ exynos_pcie_sideband_dbi_w_mode(exynos_pcie, false);
+ return ret;
+}
+
+static struct pcie_host_ops exynos_pcie_host_ops = {
+ .readl_rc = exynos_pcie_readl_rc,
+ .writel_rc = exynos_pcie_writel_rc,
+ .rd_own_conf = exynos_pcie_rd_own_conf,
+ .wr_own_conf = exynos_pcie_wr_own_conf,
+ .host_init = exynos_pcie_host_init,
+ .link_up = exynos_pcie_link_up,
+};
+
+static int __init exynos_pcie_probe(struct platform_device *pdev)
+{
+ struct exynos_pcie *exynos_pcie;
+ struct pcie_port *pp;
+ struct resource *res;
+ int ret;
+
+ exynos_pcie = devm_kzalloc(&pdev->dev, sizeof(*exynos_pcie),
+ GFP_KERNEL);
+ if (!exynos_pcie)
+ return -ENOMEM;
+
+ pp = &exynos_pcie->pp;
+ pp->dev = &pdev->dev;
+
+ exynos_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
+ if (IS_ERR(exynos_pcie->clk)) {
+ dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
+ return PTR_ERR(exynos_pcie->clk);
+ }
+ ret = clk_prepare_enable(exynos_pcie->clk);
+ if (ret)
+ return ret;
+
+ exynos_pcie->bus_clk = devm_clk_get(&pdev->dev, "pcie_bus");
+ if (IS_ERR(exynos_pcie->bus_clk)) {
+ dev_err(&pdev->dev, "Failed to get pcie bus clock\n");
+ ret = PTR_ERR(exynos_pcie->bus_clk);
+ goto fail_clk;
+ }
+ ret = clk_prepare_enable(exynos_pcie->bus_clk);
+ if (ret)
+ goto fail_clk;
+
+ /* External Local Bus interface(ELBI) Register */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
+ exynos_pcie->elbi_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(exynos_pcie->elbi_base)) {
+ ret = PTR_ERR(exynos_pcie->elbi_base);
+ goto fail_bus_clk;
+ }
+
+ /* Data Bus Interface(DBI) Register */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ pp->dbi_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pp->dbi_base)) {
+ ret = PTR_ERR(pp->dbi_base);
+ goto fail_bus_clk;
+ }
+
+ exynos_pcie->phy = devm_phy_get(&pdev->dev, "pcie-phy");
+ if (IS_ERR(exynos_pcie->phy)) {
+ if (PTR_ERR(exynos_pcie->phy) != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "Can't find the pcie-phy\n");
+ return PTR_ERR(exynos_pcie->phy);
+ }
+
+ pp->irq = platform_get_irq_byname(pdev, "intr");
+ if (!pp->irq) {
+ dev_err(&pdev->dev, "failed to get irq\n");
+ ret = -ENODEV;
+ goto fail_bus_clk;
+ }
+ ret = devm_request_irq(&pdev->dev, pp->irq, exynos_pcie_irq_handler,
+ IRQF_SHARED, "exynos-pcie", exynos_pcie);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request irq\n");
+ goto fail_bus_clk;
+ }
+
+ pp->root_bus_nr = -1;
+ pp->ops = &exynos_pcie_host_ops;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize host\n");
+ goto fail_bus_clk;
+ }
+
+ platform_set_drvdata(pdev, exynos_pcie);
+
+ return 0;
+
+fail_bus_clk:
+ clk_disable_unprepare(exynos_pcie->bus_clk);
+fail_clk:
+ clk_disable_unprepare(exynos_pcie->clk);
+ return ret;
+}
+
+static const struct of_device_id exynos_pcie_of_match[] = {
+ { .compatible = "samsung,exynos5433-pcie", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, exynos_pcie_of_match);
+
+static struct platform_driver exynos_pcie_driver = {
+ .probe = exynos_pcie_probe,
+ .driver = {
+ .name = "exynos5433-pcie",
+ .of_match_table = exynos_pcie_of_match,
+ },
+};
+builtin_platform_driver(exynos_pcie_driver);
--
2.10.2