pci: Add PCIe driver for Samsung Exynos

Exynos5440 has a PCIe controller which can be used as Root Complex.
This driver supports a PCIe controller as Root Complex mode.

Signed-off-by: Surendranath Gurivireddy Balla <suren.reddy@samsung.com>
Signed-off-by: Siva Reddy Kallam <siva.kallam@samsung.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Pratyush Anand <pratyush.anand@st.com>
Cc: Mohit KUMAR <Mohit.KUMAR@st.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

3 files changed, 1067 insertions, 0 deletions

diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 1f1d67fec8b2..1184ff6fe864 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -5,4 +5,13 @@ config PCI_MVEBU
 	bool "Marvell EBU PCIe controller"
 	depends on ARCH_MVEBU || ARCH_KIRKWOOD
 
+config PCIE_DW
+	bool
+
+config PCI_EXYNOS
+	bool "Samsung Exynos PCIe controller"
+	depends on SOC_EXYNOS5440
+	select PCIEPORTBUS
+	select PCIE_DW
+
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 5ea2d8bf013a..086d8500e849 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
+obj-$(CONFIG_PCIE_DW) += pcie-designware.o
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
new file mode 100644
index 000000000000..26bdbda8ff90
--- /dev/null
+++ b/drivers/pci/host/pcie-designware.c
@@ -0,0 +1,1057 @@
+/*
+ * PCIe host controller driver for Samsung EXYNOS SoCs
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Jingoo Han <jg1.han@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/delay.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_gpio.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+struct pcie_port_info {
+	u32		cfg0_size;
+	u32		cfg1_size;
+	u32		io_size;
+	u32		mem_size;
+	phys_addr_t	io_bus_addr;
+	phys_addr_t	mem_bus_addr;
+};
+
+struct pcie_port {
+	struct device		*dev;
+	u8			controller;
+	u8			root_bus_nr;
+	void __iomem		*dbi_base;
+	void __iomem		*elbi_base;
+	void __iomem		*phy_base;
+	void __iomem		*purple_base;
+	u64			cfg0_base;
+	void __iomem		*va_cfg0_base;
+	u64			cfg1_base;
+	void __iomem		*va_cfg1_base;
+	u64			io_base;
+	u64			mem_base;
+	spinlock_t		conf_lock;
+	struct resource		cfg;
+	struct resource		io;
+	struct resource		mem;
+	struct pcie_port_info	config;
+	struct clk		*clk;
+	struct clk		*bus_clk;
+	int			irq;
+	int			reset_gpio;
+};
+
+/*
+ * Exynos PCIe IP consists of Synopsys specific part and Exynos
+ * specific part. Only core block is a Synopsys designware part;
+ * other parts are Exynos specific.
+ */
+
+/* Synopsis specific PCIE configuration registers */
+#define PCIE_PORT_LINK_CONTROL		0x710
+#define PORT_LINK_MODE_MASK		(0x3f << 16)
+#define PORT_LINK_MODE_4_LANES		(0x7 << 16)
+
+#define PCIE_LINK_WIDTH_SPEED_CONTROL	0x80C
+#define PORT_LOGIC_SPEED_CHANGE		(0x1 << 17)
+#define PORT_LOGIC_LINK_WIDTH_MASK	(0x1ff << 8)
+#define PORT_LOGIC_LINK_WIDTH_4_LANES	(0x7 << 8)
+
+#define PCIE_MSI_ADDR_LO		0x820
+#define PCIE_MSI_ADDR_HI		0x824
+#define PCIE_MSI_INTR0_ENABLE		0x828
+#define PCIE_MSI_INTR0_MASK		0x82C
+#define PCIE_MSI_INTR0_STATUS		0x830
+
+#define PCIE_ATU_VIEWPORT		0x900
+#define PCIE_ATU_REGION_INBOUND		(0x1 << 31)
+#define PCIE_ATU_REGION_OUTBOUND	(0x0 << 31)
+#define PCIE_ATU_REGION_INDEX1		(0x1 << 0)
+#define PCIE_ATU_REGION_INDEX0		(0x0 << 0)
+#define PCIE_ATU_CR1			0x904
+#define PCIE_ATU_TYPE_MEM		(0x0 << 0)
+#define PCIE_ATU_TYPE_IO		(0x2 << 0)
+#define PCIE_ATU_TYPE_CFG0		(0x4 << 0)
+#define PCIE_ATU_TYPE_CFG1		(0x5 << 0)
+#define PCIE_ATU_CR2			0x908
+#define PCIE_ATU_ENABLE			(0x1 << 31)
+#define PCIE_ATU_BAR_MODE_ENABLE	(0x1 << 30)
+#define PCIE_ATU_LOWER_BASE		0x90C
+#define PCIE_ATU_UPPER_BASE		0x910
+#define PCIE_ATU_LIMIT			0x914
+#define PCIE_ATU_LOWER_TARGET		0x918
+#define PCIE_ATU_BUS(x)			(((x) & 0xff) << 24)
+#define PCIE_ATU_DEV(x)			(((x) & 0x1f) << 19)
+#define PCIE_ATU_FUNC(x)		(((x) & 0x7) << 16)
+#define PCIE_ATU_UPPER_TARGET		0x91C
+
+/* Exynos specific PCIE configuration registers */
+
+/* PCIe ELBI registers */
+#define PCIE_IRQ_PULSE			0x000
+#define IRQ_INTA_ASSERT			(0x1 << 0)
+#define IRQ_INTB_ASSERT			(0x1 << 2)
+#define IRQ_INTC_ASSERT			(0x1 << 4)
+#define IRQ_INTD_ASSERT			(0x1 << 6)
+#define PCIE_IRQ_LEVEL			0x004
+#define PCIE_IRQ_SPECIAL		0x008
+#define PCIE_IRQ_EN_PULSE		0x00c
+#define PCIE_IRQ_EN_LEVEL		0x010
+#define PCIE_IRQ_EN_SPECIAL		0x014
+#define PCIE_PWR_RESET			0x018
+#define PCIE_CORE_RESET			0x01c
+#define PCIE_CORE_RESET_ENABLE		(0x1 << 0)
+#define PCIE_STICKY_RESET		0x020
+#define PCIE_NONSTICKY_RESET		0x024
+#define PCIE_APP_INIT_RESET		0x028
+#define PCIE_APP_LTSSM_ENABLE		0x02c
+#define PCIE_ELBI_RDLH_LINKUP		0x064
+#define PCIE_ELBI_LTSSM_ENABLE		0x1
+#define PCIE_ELBI_SLV_AWMISC		0x11c
+#define PCIE_ELBI_SLV_ARMISC		0x120
+#define PCIE_ELBI_SLV_DBI_ENABLE	(0x1 << 21)
+
+/* PCIe Purple registers */
+#define PCIE_PHY_GLOBAL_RESET		0x000
+#define PCIE_PHY_COMMON_RESET		0x004
+#define PCIE_PHY_CMN_REG		0x008
+#define PCIE_PHY_MAC_RESET		0x00c
+#define PCIE_PHY_PLL_LOCKED		0x010
+#define PCIE_PHY_TRSVREG_RESET		0x020
+#define PCIE_PHY_TRSV_RESET		0x024
+
+/* PCIe PHY registers */
+#define PCIE_PHY_IMPEDANCE		0x004
+#define PCIE_PHY_PLL_DIV_0		0x008
+#define PCIE_PHY_PLL_BIAS		0x00c
+#define PCIE_PHY_DCC_FEEDBACK		0x014
+#define PCIE_PHY_PLL_DIV_1		0x05c
+#define PCIE_PHY_TRSV0_EMP_LVL		0x084
+#define PCIE_PHY_TRSV0_DRV_LVL		0x088
+#define PCIE_PHY_TRSV0_RXCDR		0x0ac
+#define PCIE_PHY_TRSV0_LVCC		0x0dc
+#define PCIE_PHY_TRSV1_EMP_LVL		0x144
+#define PCIE_PHY_TRSV1_RXCDR		0x16c
+#define PCIE_PHY_TRSV1_LVCC		0x19c
+#define PCIE_PHY_TRSV2_EMP_LVL		0x204
+#define PCIE_PHY_TRSV2_RXCDR		0x22c
+#define PCIE_PHY_TRSV2_LVCC		0x25c
+#define PCIE_PHY_TRSV3_EMP_LVL		0x2c4
+#define PCIE_PHY_TRSV3_RXCDR		0x2ec
+#define PCIE_PHY_TRSV3_LVCC		0x31c
+
+static struct hw_pci exynos_pci;
+
+static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
+{
+	return sys->private_data;
+}
+
+static inline int cfg_read(void *addr, int where, int size, u32 *val)
+{
+	*val = readl(addr);
+
+	if (size == 1)
+		*val = (*val >> (8 * (where & 3))) & 0xff;
+	else if (size == 2)
+		*val = (*val >> (8 * (where & 3))) & 0xffff;
+	else if (size != 4)
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int cfg_write(void *addr, int where, int size, u32 val)
+{
+	if (size == 4)
+		writel(val, addr);
+	else if (size == 2)
+		writew(val, addr + (where & 2));
+	else if (size == 1)
+		writeb(val, addr + (where & 3));
+	else
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static void exynos_pcie_sideband_dbi_w_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+
+	if (on) {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	} else {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	}
+}
+
+static void exynos_pcie_sideband_dbi_r_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+
+	if (on) {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	} else {
+		val = readl(pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, pp->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	}
+}
+
+static inline void readl_rc(struct pcie_port *pp, void *dbi_base, u32 *val)
+{
+	exynos_pcie_sideband_dbi_r_mode(pp, true);
+	*val = readl(dbi_base);
+	exynos_pcie_sideband_dbi_r_mode(pp, false);
+	return;
+}
+
+static inline void writel_rc(struct pcie_port *pp, u32 val, void *dbi_base)
+{
+	exynos_pcie_sideband_dbi_w_mode(pp, true);
+	writel(val, dbi_base);
+	exynos_pcie_sideband_dbi_w_mode(pp, false);
+	return;
+}
+
+static int exynos_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
+				u32 *val)
+{
+	int ret;
+
+	exynos_pcie_sideband_dbi_r_mode(pp, true);
+	ret = cfg_read(pp->dbi_base + (where & ~0x3), where, size, val);
+	exynos_pcie_sideband_dbi_r_mode(pp, false);
+	return ret;
+}
+
+static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
+				u32 val)
+{
+	int ret;
+
+	exynos_pcie_sideband_dbi_w_mode(pp, true);
+	ret = cfg_write(pp->dbi_base + (where & ~0x3), where, size, val);
+	exynos_pcie_sideband_dbi_w_mode(pp, false);
+	return ret;
+}
+
+static void exynos_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32 busdev)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 0 : OUTBOUND : CFG0 */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, pp->cfg0_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, (pp->cfg0_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, pp->cfg0_base + pp->config.cfg0_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+	writel_rc(pp, PCIE_ATU_TYPE_CFG0, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+}
+
+static void exynos_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32 busdev)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 1 : OUTBOUND : CFG1 */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_CFG1, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, pp->cfg1_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, (pp->cfg1_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, pp->cfg1_base + pp->config.cfg1_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, busdev, dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, 0, dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_mem_outbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 0 : OUTBOUND : MEM */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_MEM, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, pp->mem_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, (pp->mem_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, pp->mem_base + pp->config.mem_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, pp->config.mem_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, upper_32_bits(pp->config.mem_bus_addr),
+			dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static void exynos_pcie_prog_viewport_io_outbound(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *dbi_base = pp->dbi_base;
+
+	/* Program viewport 1 : OUTBOUND : IO */
+	val = PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_VIEWPORT);
+	writel_rc(pp, PCIE_ATU_TYPE_IO, dbi_base + PCIE_ATU_CR1);
+	val = PCIE_ATU_ENABLE;
+	writel_rc(pp, val, dbi_base + PCIE_ATU_CR2);
+	writel_rc(pp, pp->io_base, dbi_base + PCIE_ATU_LOWER_BASE);
+	writel_rc(pp, (pp->io_base >> 32), dbi_base + PCIE_ATU_UPPER_BASE);
+	writel_rc(pp, pp->io_base + pp->config.io_size - 1,
+			dbi_base + PCIE_ATU_LIMIT);
+	writel_rc(pp, pp->config.io_bus_addr,
+			dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel_rc(pp, upper_32_bits(pp->config.io_bus_addr),
+			dbi_base + PCIE_ATU_UPPER_TARGET);
+}
+
+static int exynos_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+		u32 devfn, int where, int size, u32 *val)
+{
+	int ret = PCIBIOS_SUCCESSFUL;
+	u32 address, busdev;
+
+	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
+		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
+	address = where & ~0x3;
+
+	if (bus->parent->number == pp->root_bus_nr) {
+		exynos_pcie_prog_viewport_cfg0(pp, busdev);
+		ret = cfg_read(pp->va_cfg0_base + address, where, size, val);
+		exynos_pcie_prog_viewport_mem_outbound(pp);
+	} else {
+		exynos_pcie_prog_viewport_cfg1(pp, busdev);
+		ret = cfg_read(pp->va_cfg1_base + address, where, size, val);
+		exynos_pcie_prog_viewport_io_outbound(pp);
+	}
+
+	return ret;
+}
+
+static int exynos_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+		u32 devfn, int where, int size, u32 val)
+{
+	int ret = PCIBIOS_SUCCESSFUL;
+	u32 address, busdev;
+
+	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
+		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
+	address = where & ~0x3;
+
+	if (bus->parent->number == pp->root_bus_nr) {
+		exynos_pcie_prog_viewport_cfg0(pp, busdev);
+		ret = cfg_write(pp->va_cfg0_base + address, where, size, val);
+		exynos_pcie_prog_viewport_mem_outbound(pp);
+	} else {
+		exynos_pcie_prog_viewport_cfg1(pp, busdev);
+		ret = cfg_write(pp->va_cfg1_base + address, where, size, val);
+		exynos_pcie_prog_viewport_io_outbound(pp);
+	}
+
+	return ret;
+}
+
+static unsigned long global_io_offset;
+
+static int exynos_pcie_setup(int nr, struct pci_sys_data *sys)
+{
+	struct pcie_port *pp;
+
+	pp = sys_to_pcie(sys);
+
+	if (!pp)
+		return 0;
+
+	if (global_io_offset < SZ_1M && pp->config.io_size > 0) {
+		sys->io_offset = global_io_offset - pp->config.io_bus_addr;
+		pci_ioremap_io(sys->io_offset, pp->io.start);
+		global_io_offset += SZ_64K;
+		pci_add_resource_offset(&sys->resources, &pp->io,
+					sys->io_offset);
+	}
+
+	sys->mem_offset = pp->mem.start - pp->config.mem_bus_addr;
+	pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);
+
+	return 1;
+}
+
+static int exynos_pcie_link_up(struct pcie_port *pp)
+{
+	u32 val = readl(pp->elbi_base + PCIE_ELBI_RDLH_LINKUP);
+
+	if (val == PCIE_ELBI_LTSSM_ENABLE)
+		return 1;
+
+	return 0;
+}
+
+static int exynos_pcie_valid_config(struct pcie_port *pp,
+				struct pci_bus *bus, int dev)
+{
+	/* If there is no link, then there is no device */
+	if (bus->number != pp->root_bus_nr) {
+		if (!exynos_pcie_link_up(pp))
+			return 0;
+	}
+
+	/* access only one slot on each root port */
+	if (bus->number == pp->root_bus_nr && dev > 0)
+		return 0;
+
+	/*
+	 * do not read more than one device on the bus directly attached
+	 * to RC's (Virtual Bridge's) DS side.
+	 */
+	if (bus->primary == pp->root_bus_nr && dev > 0)
+		return 0;
+
+	return 1;
+}
+
+static int exynos_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
+			int size, u32 *val)
+{
+	struct pcie_port *pp = sys_to_pcie(bus->sysdata);
+	unsigned long flags;
+	int ret;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (exynos_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
+		*val = 0xffffffff;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	spin_lock_irqsave(&pp->conf_lock, flags);
+	if (bus->number != pp->root_bus_nr)
+		ret = exynos_pcie_rd_other_conf(pp, bus, devfn,
+						where, size, val);
+	else
+		ret = exynos_pcie_rd_own_conf(pp, where, size, val);
+	spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+	return ret;
+}
+
+static int exynos_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
+			int where, int size, u32 val)
+{
+	struct pcie_port *pp = sys_to_pcie(bus->sysdata);
+	unsigned long flags;
+	int ret;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (exynos_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	spin_lock_irqsave(&pp->conf_lock, flags);
+	if (bus->number != pp->root_bus_nr)
+		ret = exynos_pcie_wr_other_conf(pp, bus, devfn,
+						where, size, val);
+	else
+		ret = exynos_pcie_wr_own_conf(pp, where, size, val);
+	spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+	return ret;
+}
+
+static struct pci_ops exynos_pcie_ops = {
+	.read = exynos_pcie_rd_conf,
+	.write = exynos_pcie_wr_conf,
+};
+
+static struct pci_bus *exynos_pcie_scan_bus(int nr,
+					struct pci_sys_data *sys)
+{
+	struct pci_bus *bus;
+	struct pcie_port *pp = sys_to_pcie(sys);
+
+	if (pp) {
+		pp->root_bus_nr = sys->busnr;
+		bus = pci_scan_root_bus(NULL, sys->busnr, &exynos_pcie_ops,
+					sys, &sys->resources);
+	} else {
+		bus = NULL;
+		BUG();
+	}
+
+	return bus;
+}
+
+static int exynos_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
+
+	return pp->irq;
+}
+
+static struct hw_pci exynos_pci = {
+	.setup		= exynos_pcie_setup,
+	.scan		= exynos_pcie_scan_bus,
+	.map_irq	= exynos_pcie_map_irq,
+};
+
+static void exynos_pcie_setup_rc(struct pcie_port *pp)
+{
+	struct pcie_port_info *config = &pp->config;
+	void __iomem *dbi_base = pp->dbi_base;
+	u32 val;
+	u32 membase;
+	u32 memlimit;
+
+	/* set the number of lines as 4 */
+	readl_rc(pp, dbi_base + PCIE_PORT_LINK_CONTROL, &val);
+	val &= ~PORT_LINK_MODE_MASK;
+	val |= PORT_LINK_MODE_4_LANES;
+	writel_rc(pp, val, dbi_base + PCIE_PORT_LINK_CONTROL);
+
+	/* set link width speed control register */
+	readl_rc(pp, dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL, &val);
+	val &= ~PORT_LOGIC_LINK_WIDTH_MASK;
+	val |= PORT_LOGIC_LINK_WIDTH_4_LANES;
+	writel_rc(pp, val, dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+
+	/* setup RC BARs */
+	writel_rc(pp, 0x00000004, dbi_base + PCI_BASE_ADDRESS_0);
+	writel_rc(pp, 0x00000004, dbi_base + PCI_BASE_ADDRESS_1);
+
+	/* setup interrupt pins */
+	readl_rc(pp, dbi_base + PCI_INTERRUPT_LINE, &val);
+	val &= 0xffff00ff;
+	val |= 0x00000100;
+	writel_rc(pp, val, dbi_base + PCI_INTERRUPT_LINE);
+
+	/* setup bus numbers */
+	readl_rc(pp, dbi_base + PCI_PRIMARY_BUS, &val);
+	val &= 0xff000000;
+	val |= 0x00010100;
+	writel_rc(pp, val, dbi_base + PCI_PRIMARY_BUS);
+
+	/* setup memory base, memory limit */
+	membase = ((u32)pp->mem_base & 0xfff00000) >> 16;
+	memlimit = (config->mem_size + (u32)pp->mem_base) & 0xfff00000;
+	val = memlimit | membase;
+	writel_rc(pp, val, dbi_base + PCI_MEMORY_BASE);
+
+	/* setup command register */
+	readl_rc(pp, dbi_base + PCI_COMMAND, &val);
+	val &= 0xffff0000;
+	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
+		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
+	writel_rc(pp, val, dbi_base + PCI_COMMAND);
+}
+
+static void exynos_pcie_assert_core_reset(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	val = readl(elbi_base + PCIE_CORE_RESET);
+	val &= ~PCIE_CORE_RESET_ENABLE;
+	writel(val, elbi_base + PCIE_CORE_RESET);
+	writel(0, elbi_base + PCIE_PWR_RESET);
+	writel(0, elbi_base + PCIE_STICKY_RESET);
+	writel(0, elbi_base + PCIE_NONSTICKY_RESET);
+}
+
+static void exynos_pcie_deassert_core_reset(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+
+	val = readl(elbi_base + PCIE_CORE_RESET);
+	val |= PCIE_CORE_RESET_ENABLE;
+	writel(val, elbi_base + PCIE_CORE_RESET);
+	writel(1, elbi_base + PCIE_STICKY_RESET);
+	writel(1, elbi_base + PCIE_NONSTICKY_RESET);
+	writel(1, elbi_base + PCIE_APP_INIT_RESET);
+	writel(0, elbi_base + PCIE_APP_INIT_RESET);
+	writel(1, purple_base + PCIE_PHY_MAC_RESET);
+}
+
+static void exynos_pcie_assert_phy_reset(struct pcie_port *pp)
+{
+	void __iomem *purple_base = pp->purple_base;
+
+	writel(0, purple_base + PCIE_PHY_MAC_RESET);
+	writel(1, purple_base + PCIE_PHY_GLOBAL_RESET);
+}
+
+static void exynos_pcie_deassert_phy_reset(struct pcie_port *pp)
+{
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+
+	writel(0, purple_base + PCIE_PHY_GLOBAL_RESET);
+	writel(1, elbi_base + PCIE_PWR_RESET);
+	writel(0, purple_base + PCIE_PHY_COMMON_RESET);
+	writel(0, purple_base + PCIE_PHY_CMN_REG);
+	writel(0, purple_base + PCIE_PHY_TRSVREG_RESET);
+	writel(0, purple_base + PCIE_PHY_TRSV_RESET);
+}
+
+static void exynos_pcie_init_phy(struct pcie_port *pp)
+{
+	void __iomem *phy_base = pp->phy_base;
+
+	/* DCC feedback control off */
+	writel(0x29, phy_base + PCIE_PHY_DCC_FEEDBACK);
+
+	/* set TX/RX impedance */
+	writel(0xd5, phy_base + PCIE_PHY_IMPEDANCE);
+
+	/* set 50Mhz PHY clock */
+	writel(0x14, phy_base + PCIE_PHY_PLL_DIV_0);
+	writel(0x12, phy_base + PCIE_PHY_PLL_DIV_1);
+
+	/* set TX Differential output for lane 0 */
+	writel(0x7f, phy_base + PCIE_PHY_TRSV0_DRV_LVL);
+
+	/* set TX Pre-emphasis Level Control for lane 0 to minimum */
+	writel(0x0, phy_base + PCIE_PHY_TRSV0_EMP_LVL);
+
+	/* set RX clock and data recovery bandwidth */
+	writel(0xe7, phy_base + PCIE_PHY_PLL_BIAS);
+	writel(0x82, phy_base + PCIE_PHY_TRSV0_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV1_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV2_RXCDR);
+	writel(0x82, phy_base + PCIE_PHY_TRSV3_RXCDR);
+
+	/* change TX Pre-emphasis Level Control for lanes */
+	writel(0x39, phy_base + PCIE_PHY_TRSV0_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV1_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV2_EMP_LVL);
+	writel(0x39, phy_base + PCIE_PHY_TRSV3_EMP_LVL);
+
+	/* set LVCC */
+	writel(0x20, phy_base + PCIE_PHY_TRSV0_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV1_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV2_LVCC);
+	writel(0xa0, phy_base + PCIE_PHY_TRSV3_LVCC);
+}
+
+static void exynos_pcie_assert_reset(struct pcie_port *pp)
+{
+	if (pp->reset_gpio >= 0)
+		devm_gpio_request_one(pp->dev, pp->reset_gpio,
+				GPIOF_OUT_INIT_HIGH, "RESET");
+	return;
+}
+
+static int exynos_pcie_establish_link(struct pcie_port *pp)
+{
+	u32 val;
+	int count = 0;
+	void __iomem *elbi_base = pp->elbi_base;
+	void __iomem *purple_base = pp->purple_base;
+	void __iomem *phy_base = pp->phy_base;
+
+	if (exynos_pcie_link_up(pp)) {
+		dev_err(pp->dev, "Link already up\n");
+		return 0;
+	}
+
+	/* assert reset signals */
+	exynos_pcie_assert_core_reset(pp);
+	exynos_pcie_assert_phy_reset(pp);
+
+	/* de-assert phy reset */
+	exynos_pcie_deassert_phy_reset(pp);
+
+	/* initialize phy */
+	exynos_pcie_init_phy(pp);
+
+	/* pulse for common reset */
+	writel(1, purple_base + PCIE_PHY_COMMON_RESET);
+	udelay(500);
+	writel(0, purple_base + PCIE_PHY_COMMON_RESET);
+
+	/* de-assert core reset */
+	exynos_pcie_deassert_core_reset(pp);
+
+	/* setup root complex */
+	exynos_pcie_setup_rc(pp);
+
+	/* assert reset signal */
+	exynos_pcie_assert_reset(pp);
+
+	/* assert LTSSM enable */
+	writel(PCIE_ELBI_LTSSM_ENABLE, elbi_base + PCIE_APP_LTSSM_ENABLE);
+
+	/* check if the link is up or not */
+	while (!exynos_pcie_link_up(pp)) {
+		mdelay(100);
+		count++;
+		if (count == 10) {
+			while (readl(phy_base + PCIE_PHY_PLL_LOCKED) == 0) {
+				val = readl(purple_base + PCIE_PHY_PLL_LOCKED);
+				dev_info(pp->dev, "PLL Locked: 0x%x\n", val);
+			}
+			dev_err(pp->dev, "PCIe Link Fail\n");
+			return -EINVAL;
+		}
+	}
+
+	dev_info(pp->dev, "Link up\n");
+
+	return 0;
+}
+
+static void exynos_pcie_clear_irq_pulse(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	val = readl(elbi_base + PCIE_IRQ_PULSE);
+	writel(val, elbi_base + PCIE_IRQ_PULSE);
+	return;
+}
+
+static void exynos_pcie_enable_irq_pulse(struct pcie_port *pp)
+{
+	u32 val;
+	void __iomem *elbi_base = pp->elbi_base;
+
+	/* enable INTX interrupt */
+	val = IRQ_INTA_ASSERT | IRQ_INTB_ASSERT |
+		IRQ_INTC_ASSERT | IRQ_INTD_ASSERT,
+	writel(val, elbi_base + PCIE_IRQ_EN_PULSE);
+	return;
+}
+
+static irqreturn_t exynos_pcie_irq_handler(int irq, void *arg)
+{
+	struct pcie_port *pp = arg;
+
+	exynos_pcie_clear_irq_pulse(pp);
+	return IRQ_HANDLED;
+}
+
+static void exynos_pcie_enable_interrupts(struct pcie_port *pp)
+{
+	exynos_pcie_enable_irq_pulse(pp);
+	return;
+}
+
+static void exynos_pcie_host_init(struct pcie_port *pp)
+{
+	struct pcie_port_info *config = &pp->config;
+	u32 val;
+
+	/* Keep first 64K for IO */
+	pp->cfg0_base = pp->cfg.start;
+	pp->cfg1_base = pp->cfg.start + config->cfg0_size;
+	pp->io_base = pp->io.start;
+	pp->mem_base = pp->mem.start;
+
+	/* enable link */
+	exynos_pcie_establish_link(pp);
+
+	exynos_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0);
+
+	/* program correct class for RC */
+	exynos_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI);
+
+	exynos_pcie_rd_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, &val);
+	val |= PORT_LOGIC_SPEED_CHANGE;
+	exynos_pcie_wr_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, val);
+
+	exynos_pcie_enable_interrupts(pp);
+}
+
+static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev)
+{
+	struct resource *elbi_base;
+	struct resource *phy_base;
+	struct resource *purple_base;
+	int ret;
+
+	elbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!elbi_base) {
+		dev_err(&pdev->dev, "couldn't get elbi base resource\n");
+		return -EINVAL;
+	}
+	pp->elbi_base = devm_ioremap_resource(&pdev->dev, elbi_base);
+	if (IS_ERR(pp->elbi_base))
+		return PTR_ERR(pp->elbi_base);
+
+	phy_base = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!phy_base) {
+		dev_err(&pdev->dev, "couldn't get phy base resource\n");
+		return -EINVAL;
+	}
+	pp->phy_base = devm_ioremap_resource(&pdev->dev, phy_base);
+	if (IS_ERR(pp->phy_base))
+		return PTR_ERR(pp->phy_base);
+
+	purple_base = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!purple_base) {
+		dev_err(&pdev->dev, "couldn't get purple base resource\n");
+		return -EINVAL;
+	}
+	pp->purple_base = devm_ioremap_resource(&pdev->dev, purple_base);
+	if (IS_ERR(pp->purple_base))
+		return PTR_ERR(pp->purple_base);
+
+	pp->irq = platform_get_irq(pdev, 1);
+	if (!pp->irq) {
+		dev_err(&pdev->dev, "failed to get irq\n");
+		return -ENODEV;
+	}
+	ret = devm_request_irq(&pdev->dev, pp->irq, exynos_pcie_irq_handler,
+				IRQF_SHARED, "exynos-pcie", pp);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		return ret;
+	}
+
+	pp->dbi_base = devm_ioremap(&pdev->dev, pp->cfg.start,
+				resource_size(&pp->cfg));
+	if (!pp->dbi_base) {
+		dev_err(&pdev->dev, "error with ioremap\n");
+		return -ENOMEM;
+	}
+
+	pp->root_bus_nr = -1;
+
+	spin_lock_init(&pp->conf_lock);
+	exynos_pcie_host_init(pp);
+	pp->va_cfg0_base = devm_ioremap(&pdev->dev, pp->cfg0_base,
+					pp->config.cfg0_size);
+	if (!pp->va_cfg0_base) {
+		dev_err(pp->dev, "error with ioremap in function\n");
+		return -ENOMEM;
+	}
+	pp->va_cfg1_base = devm_ioremap(&pdev->dev, pp->cfg1_base,
+					pp->config.cfg1_size);
+	if (!pp->va_cfg1_base) {
+		dev_err(pp->dev, "error with ioremap\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int __init exynos_pcie_probe(struct platform_device *pdev)
+{
+	struct pcie_port *pp;
+	struct device_node *np = pdev->dev.of_node;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	int ret;
+
+	pp = devm_kzalloc(&pdev->dev, sizeof(*pp), GFP_KERNEL);
+	if (!pp) {
+		dev_err(&pdev->dev, "no memory for pcie port\n");
+		return -ENOMEM;
+	}
+
+	pp->dev = &pdev->dev;
+
+	if (of_pci_range_parser_init(&parser, np)) {
+		dev_err(&pdev->dev, "missing ranges property\n");
+		return -EINVAL;
+	}
+
+	/* Get the I/O and memory ranges from DT */
+	for_each_of_pci_range(&parser, &range) {
+		unsigned long restype = range.flags & IORESOURCE_TYPE_BITS;
+		if (restype == IORESOURCE_IO) {
+			of_pci_range_to_resource(&range, np, &pp->io);
+			pp->io.name = "I/O";
+			pp->io.start = max_t(resource_size_t,
+					     PCIBIOS_MIN_IO,
+					     range.pci_addr + global_io_offset);
+			pp->io.end = min_t(resource_size_t,
+					   IO_SPACE_LIMIT,
+					   range.pci_addr + range.size
+					   + global_io_offset);
+			pp->config.io_size = resource_size(&pp->io);
+			pp->config.io_bus_addr = range.pci_addr;
+		}
+		if (restype == IORESOURCE_MEM) {
+			of_pci_range_to_resource(&range, np, &pp->mem);
+			pp->mem.name = "MEM";
+			pp->config.mem_size = resource_size(&pp->mem);
+			pp->config.mem_bus_addr = range.pci_addr;
+		}
+		if (restype == 0) {
+			of_pci_range_to_resource(&range, np, &pp->cfg);
+			pp->config.cfg0_size = resource_size(&pp->cfg)/2;
+			pp->config.cfg1_size = resource_size(&pp->cfg)/2;
+		}
+	}
+
+	pp->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+
+	pp->clk = devm_clk_get(&pdev->dev, "pcie");
+	if (IS_ERR(pp->clk)) {
+		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
+		return PTR_ERR(pp->clk);
+	}
+	ret = clk_prepare_enable(pp->clk);
+	if (ret)
+		return ret;
+
+	pp->bus_clk = devm_clk_get(&pdev->dev, "pcie_bus");
+	if (IS_ERR(pp->bus_clk)) {
+		dev_err(&pdev->dev, "Failed to get pcie bus clock\n");
+		ret = PTR_ERR(pp->bus_clk);
+		goto fail_clk;
+	}
+	ret = clk_prepare_enable(pp->bus_clk);
+	if (ret)
+		goto fail_clk;
+
+	ret = add_pcie_port(pp, pdev);
+	if (ret < 0)
+		goto fail_bus_clk;
+
+	pp->controller = exynos_pci.nr_controllers;
+	exynos_pci.nr_controllers = 1;
+	exynos_pci.private_data = (void **)&pp;
+
+	pci_common_init(&exynos_pci);
+	pci_assign_unassigned_resources();
+#ifdef CONFIG_PCI_DOMAINS
+	exynos_pci.domain++;
+#endif
+
+	platform_set_drvdata(pdev, pp);
+	return 0;
+
+fail_bus_clk:
+	clk_disable_unprepare(pp->bus_clk);
+fail_clk:
+	clk_disable_unprepare(pp->clk);
+	return ret;
+}
+
+static int __exit exynos_pcie_remove(struct platform_device *pdev)
+{
+	struct pcie_port *pp = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(pp->bus_clk);
+	clk_disable_unprepare(pp->clk);
+
+	return 0;
+}
+
+static const struct of_device_id exynos_pcie_of_match[] = {
+	{ .compatible = "samsung,exynos5440-pcie", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, exynos_pcie_of_match);
+
+static struct platform_driver exynos_pcie_driver = {
+	.remove		= __exit_p(exynos_pcie_remove),
+	.driver = {
+		.name	= "exynos-pcie",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(exynos_pcie_of_match),
+	},
+};
+
+static int exynos_pcie_abort(unsigned long addr, unsigned int fsr,
+			struct pt_regs *regs)
+{
+	unsigned long pc = instruction_pointer(regs);
+	unsigned long instr = *(unsigned long *)pc;
+
+	WARN_ONCE(1, "pcie abort\n");
+
+	/*
+	 * If the instruction being executed was a read,
+	 * make it look like it read all-ones.
+	 */
+	if ((instr & 0x0c100000) == 0x04100000) {
+		int reg = (instr >> 12) & 15;
+		unsigned long val;
+
+		if (instr & 0x00400000)
+			val = 255;
+		else
+			val = -1;
+
+		regs->uregs[reg] = val;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	if ((instr & 0x0e100090) == 0x00100090) {
+		int reg = (instr >> 12) & 15;
+
+		regs->uregs[reg] = -1;
+		regs->ARM_pc += 4;
+		return 0;
+	}
+
+	return 1;
+}
+
+/* Exynos PCIe driver does not allow module unload */
+
+static int __init pcie_init(void)
+{
+	hook_fault_code(16 + 6, exynos_pcie_abort, SIGBUS, 0,
+			"imprecise external abort");
+
+	platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);
+
+	return 0;
+}
+subsys_initcall(pcie_init);
+
+MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
+MODULE_DESCRIPTION("Samsung PCIe host controller driver");
+MODULE_LICENSE("GPL v2");