PCI: exynos: Split into Synopsys part and Exynos part

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.

Also, the Synopsys Designware part can be shared with other
platforms; thus, it can be split two parts such as Synopsys
Designware part and Exynos specific part.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Pratyush Anand <pratyush.anand@st.com>
Cc: Mohit KUMAR <Mohit.KUMAR@st.com>

Documentation/devicetree/bindings/pci/designware-pcie.txt

@@ -18,6 +18,7 @@ Required properties:
 - interrupt-map-mask and interrupt-map: standard PCI properties
 	to define the mapping of the PCIe interface to interrupt
 	numbers.
+- num-lanes: number of lanes to use
 - reset-gpio: gpio pin number of power good signal
 
 Example:
@@ -41,6 +42,7 @@ SoC specific DT Entry:
 		#interrupt-cells = <1>;
 		interrupt-map-mask = <0 0 0 0>;
 		interrupt-map = <0x0 0 &gic 53>;
+		num-lanes = <4>;
 	};
 
 	pcie@2a0000 {
@@ -60,6 +62,7 @@ SoC specific DT Entry:
 		#interrupt-cells = <1>;
 		interrupt-map-mask = <0 0 0 0>;
 		interrupt-map = <0x0 0 &gic 56>;
+		num-lanes = <4>;
 	};
 
 Board specific DT Entry:

arch/arm/boot/dts/exynos5440.dtsi

@@ -248,6 +248,7 @@
 		#interrupt-cells = <1>;
 		interrupt-map-mask = <0 0 0 0>;
 		interrupt-map = <0x0 0 &gic 53>;
+		num-lanes = <4>;
 	};
 
 	pcie@2a0000 {
@@ -267,5 +268,6 @@
 		#interrupt-cells = <1>;
 		interrupt-map-mask = <0 0 0 0>;
 		interrupt-map = <0x0 0 &gic 56>;
+		num-lanes = <4>;
 	};
 };

drivers/pci/host/Makefile

-obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
 obj-$(CONFIG_PCIE_DW) += pcie-designware.o
+obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
+obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o

drivers/pci/host/pci-exynos.c

+/*
+ * 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/module.h>
+#include <linux/of_gpio.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+
+#define to_exynos_pcie(x)	container_of(x, struct exynos_pcie, pp)
+
+struct exynos_pcie {
+	void __iomem		*elbi_base;
+	void __iomem		*phy_base;
+	void __iomem		*block_base;
+	int			reset_gpio;
+	struct clk		*clk;
+	struct clk		*bus_clk;
+	struct pcie_port	pp;
+};
+
+/* 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 void exynos_pcie_sideband_dbi_w_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+
+	if (on) {
+		val = readl(exynos_pcie->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, exynos_pcie->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	} else {
+		val = readl(exynos_pcie->elbi_base + PCIE_ELBI_SLV_AWMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, exynos_pcie->elbi_base + PCIE_ELBI_SLV_AWMISC);
+	}
+}
+
+static void exynos_pcie_sideband_dbi_r_mode(struct pcie_port *pp, bool on)
+{
+	u32 val;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+
+	if (on) {
+		val = readl(exynos_pcie->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val |= PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, exynos_pcie->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	} else {
+		val = readl(exynos_pcie->elbi_base + PCIE_ELBI_SLV_ARMISC);
+		val &= ~PCIE_ELBI_SLV_DBI_ENABLE;
+		writel(val, exynos_pcie->elbi_base + PCIE_ELBI_SLV_ARMISC);
+	}
+}
+
+static void exynos_pcie_assert_core_reset(struct pcie_port *pp)
+{
+	u32 val;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->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;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->elbi_base;
+	void __iomem *block_base = exynos_pcie->block_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, block_base + PCIE_PHY_MAC_RESET);
+}
+
+static void exynos_pcie_assert_phy_reset(struct pcie_port *pp)
+{
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *block_base = exynos_pcie->block_base;
+
+	writel(0, block_base + PCIE_PHY_MAC_RESET);
+	writel(1, block_base + PCIE_PHY_GLOBAL_RESET);
+}
+
+static void exynos_pcie_deassert_phy_reset(struct pcie_port *pp)
+{
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->elbi_base;
+	void __iomem *block_base = exynos_pcie->block_base;
+
+	writel(0, block_base + PCIE_PHY_GLOBAL_RESET);
+	writel(1, elbi_base + PCIE_PWR_RESET);
+	writel(0, block_base + PCIE_PHY_COMMON_RESET);
+	writel(0, block_base + PCIE_PHY_CMN_REG);
+	writel(0, block_base + PCIE_PHY_TRSVREG_RESET);
+	writel(0, block_base + PCIE_PHY_TRSV_RESET);
+}
+
+static void exynos_pcie_init_phy(struct pcie_port *pp)
+{
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *phy_base = exynos_pcie->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)
+{
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+
+	if (exynos_pcie->reset_gpio >= 0)
+		devm_gpio_request_one(pp->dev, exynos_pcie->reset_gpio,
+				GPIOF_OUT_INIT_HIGH, "RESET");
+	return;
+}
+
+static int exynos_pcie_establish_link(struct pcie_port *pp)
+{
+	u32 val;
+	int count = 0;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->elbi_base;
+	void __iomem *block_base = exynos_pcie->block_base;
+	void __iomem *phy_base = exynos_pcie->phy_base;
+
+	if (dw_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, block_base + PCIE_PHY_COMMON_RESET);
+	udelay(500);
+	writel(0, block_base + PCIE_PHY_COMMON_RESET);
+
+	/* de-assert core reset */
+	exynos_pcie_deassert_core_reset(pp);
+
+	/* setup root complex */
+	dw_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 (!dw_pcie_link_up(pp)) {
+		mdelay(100);
+		count++;
+		if (count == 10) {
+			while (readl(phy_base + PCIE_PHY_PLL_LOCKED) == 0) {
+				val = readl(block_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;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->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;
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	void __iomem *elbi_base = exynos_pcie->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 inline void exynos_pcie_readl_rc(struct pcie_port *pp,
+					void __iomem *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 exynos_pcie_writel_rc(struct pcie_port *pp,
+					u32 val, void __iomem *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 int exynos_pcie_link_up(struct pcie_port *pp)
+{
+	struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
+	u32 val = readl(exynos_pcie->elbi_base + PCIE_ELBI_RDLH_LINKUP);
+
+	if (val == PCIE_ELBI_LTSSM_ENABLE)
+		return 1;
+
+	return 0;
+}
+
+static void exynos_pcie_host_init(struct pcie_port *pp)
+{
+	exynos_pcie_establish_link(pp);
+	exynos_pcie_enable_interrupts(pp);
+}
+
+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,
+	.link_up = exynos_pcie_link_up,
+	.host_init = exynos_pcie_host_init,
+};
+
+static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev)
+{
+	int ret;
+
+	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->root_bus_nr = -1;
+	pp->ops = &exynos_pcie_host_ops;
+
+	spin_lock_init(&pp->conf_lock);
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __init exynos_pcie_probe(struct platform_device *pdev)
+{
+	struct exynos_pcie *exynos_pcie;
+	struct pcie_port *pp;
+	struct device_node *np = pdev->dev.of_node;
+	struct resource *elbi_base;
+	struct resource *phy_base;
+	struct resource *block_base;
+	int ret;
+
+	exynos_pcie = devm_kzalloc(&pdev->dev, sizeof(*exynos_pcie),
+				GFP_KERNEL);
+	if (!exynos_pcie) {
+		dev_err(&pdev->dev, "no memory for exynos pcie\n");
+		return -ENOMEM;
+	}
+
+	pp = &exynos_pcie->pp;
+
+	pp->dev = &pdev->dev;
+
+	exynos_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+
+	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;
+
+	elbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	exynos_pcie->elbi_base = devm_ioremap_resource(&pdev->dev, elbi_base);
+	if (IS_ERR(exynos_pcie->elbi_base))
+		return PTR_ERR(exynos_pcie->elbi_base);
+
+	phy_base = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	exynos_pcie->phy_base = devm_ioremap_resource(&pdev->dev, phy_base);
+	if (IS_ERR(exynos_pcie->phy_base))
+		return PTR_ERR(exynos_pcie->phy_base);
+
+	block_base = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	exynos_pcie->block_base = devm_ioremap_resource(&pdev->dev, block_base);
+	if (IS_ERR(exynos_pcie->block_base))
+		return PTR_ERR(exynos_pcie->block_base);
+
+	ret = add_pcie_port(pp, pdev);
+	if (ret < 0)
+		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 int __exit exynos_pcie_remove(struct platform_device *pdev)
+{
+	struct exynos_pcie *exynos_pcie = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(exynos_pcie->bus_clk);
+	clk_disable_unprepare(exynos_pcie->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),
+	},
+};
+
+/* Exynos PCIe driver does not allow module unload */
+
+static int __init pcie_init(void)
+{
+	return platform_driver_probe(&exynos_pcie_driver, exynos_pcie_probe);
+}
+subsys_initcall(pcie_init);
+
+MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
+MODULE_DESCRIPTION("Samsung PCIe host controller driver");
+MODULE_LICENSE("GPL v2");

drivers/pci/host/pcie-designware.h

+/*
+ * Synopsys Designware PCIe host controller driver
+ *
+ * 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.
+ */
+
+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			root_bus_nr;
+	void __iomem		*dbi_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;
+	int			irq;
+	u32			lanes;
+	struct pcie_host_ops	*ops;
+};
+
+struct pcie_host_ops {
+	void (*readl_rc)(struct pcie_port *pp,
+			void __iomem *dbi_base, u32 *val);
+	void (*writel_rc)(struct pcie_port *pp,
+			u32 val, void __iomem *dbi_base);
+	int (*rd_own_conf)(struct pcie_port *pp, int where, int size, u32 *val);
+	int (*wr_own_conf)(struct pcie_port *pp, int where, int size, u32 val);
+	int (*link_up)(struct pcie_port *pp);
+	void (*host_init)(struct pcie_port *pp);
+};
+
+extern unsigned long global_io_offset;
+
+int cfg_read(void __iomem *addr, int where, int size, u32 *val);
+int cfg_write(void __iomem *addr, int where, int size, u32 val);
+int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size, u32 val);
+int dw_pcie_rd_own_conf(struct pcie_port *pp, int where, int size, u32 *val);
+int dw_pcie_link_up(struct pcie_port *pp);
+void dw_pcie_setup_rc(struct pcie_port *pp);
+int dw_pcie_host_init(struct pcie_port *pp);
+int dw_pcie_setup(int nr, struct pci_sys_data *sys);
+struct pci_bus *dw_pcie_scan_bus(int nr, struct pci_sys_data *sys);
+int dw_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin);