[PATCH 3/4] PCI: Add driver for i.MX6 PCI Express

Sean Cross xobs at kosagi.com
Mon Jul 1 17:15:46 EST 2013


This adds a PCI Express port driver for the on-chip PCI Express port
present on the i.MX6 SoC.  It is based on the PCI Express driver available
in the Freescale BSP.

Signed-off-by: Sean Cross <xobs at kosagi.com>
---
 .../devicetree/bindings/pci/imx6q-pcie.txt         |   20 +
 arch/arm/mach-imx/Kconfig                          |    1 +
 drivers/pci/pcie/Kconfig                           |   10 +
 drivers/pci/pcie/Makefile                          |    2 +
 drivers/pci/pcie/pcie-imx.c                        | 1049 ++++++++++++++++++++
 5 files changed, 1082 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/imx6q-pcie.txt
 create mode 100644 drivers/pci/pcie/pcie-imx.c

diff --git a/Documentation/devicetree/bindings/pci/imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/imx6q-pcie.txt
new file mode 100644
index 0000000..2dc9eae
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/imx6q-pcie.txt
@@ -0,0 +1,20 @@
+* Freescale i.MX6Q PCI Express bridge
+
+Example (i.MX6Q)
+	pcie: pcie at 01ffc000 {
+		compatible = "fsl,imx6q-pcie";
+		reg = <0x01ffc000 0x4000>,
+		      <0x01000000 0x100000>,
+		      <0x01100000 0xe00000>,
+		      <0x01f00000 0xfc000>;
+		interrupts = <0 122 0x04>;
+		clocks = <&clks 186>, <&clks 189>, <&clks 196>,
+			 <&clks 198>, <&clks 144>;
+		clock-names = "sata_ref", "pcie_ref_125m", "lvds1_sel",
+			      "lvds1", "pcie_axi";
+		power-enable = <&gpio7 12 0>;
+		pcie-reset = <&gpio3 29 0>;
+		wake-up = <&gpio3 22 0>;
+		disable-endpoint = <&gpio2 16 0>;
+	};
+
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index ba44328..cad4e5a 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -811,6 +811,7 @@ config SOC_IMX6Q
 	select PL310_ERRATA_588369 if CACHE_PL310
 	select PL310_ERRATA_727915 if CACHE_PL310
 	select PL310_ERRATA_769419 if CACHE_PL310
+	select MIGHT_HAVE_PCI
 	select PM_OPP if PM
 
 	help
diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
index 569f82f..d1d70db 100644
--- a/drivers/pci/pcie/Kconfig
+++ b/drivers/pci/pcie/Kconfig
@@ -83,3 +83,13 @@ endchoice
 config PCIE_PME
 	def_bool y
 	depends on PCIEPORTBUS && PM_RUNTIME
+
+#
+# Platform driver for i.MX6
+#
+config PCIE_IMX
+        bool "Support for i.MX6"
+        depends on SOC_IMX6Q
+        help
+          Enable support for the 1x PCI Express bus on the Freescale i.MX6
+        depends on PCIEPORTBUS && PM_RUNTIME
diff --git a/drivers/pci/pcie/Makefile b/drivers/pci/pcie/Makefile
index 00c62df..5393d21 100644
--- a/drivers/pci/pcie/Makefile
+++ b/drivers/pci/pcie/Makefile
@@ -14,3 +14,5 @@ obj-$(CONFIG_PCIEPORTBUS)	+= pcieportdrv.o
 obj-$(CONFIG_PCIEAER)		+= aer/
 
 obj-$(CONFIG_PCIE_PME) += pme.o
+
+obj-$(CONFIG_PCIE_IMX)		+= pcie-imx.o
diff --git a/drivers/pci/pcie/pcie-imx.c b/drivers/pci/pcie/pcie-imx.c
new file mode 100644
index 0000000..664679e
--- /dev/null
+++ b/drivers/pci/pcie/pcie-imx.c
@@ -0,0 +1,1049 @@
+/*
+ * drivers/pci/pcie/pcie-imx.c
+ *
+ * PCIe host controller driver for IMX6 SOCs
+ *
+ * Copyright (C) 2012 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * Code originally taken from Freescale linux-2.6.35 BSP.
+ *
+ * Other bits taken from arch/arm/mach-dove/pcie.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_device.h>
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+#include <linux/rfkill.h>
+
+#include <asm/sizes.h>
+#include <asm/io.h>
+
+
+/* IOMUXC */
+#define IOMUXC_GPR0                     (0x00)
+#define IOMUXC_GPR1                     (0x04)
+#define IOMUXC_GPR2                     (0x08)
+#define IOMUXC_GPR3                     (0x0C)
+#define IOMUXC_GPR4                     (0x10)
+#define IOMUXC_GPR5                     (0x14)
+#define IOMUXC_GPR6                     (0x18)
+#define IOMUXC_GPR7                     (0x1C)
+#define IOMUXC_GPR8                     (0x20)
+#define IOMUXC_GPR9                     (0x24)
+#define IOMUXC_GPR10                    (0x28)
+#define IOMUXC_GPR11                    (0x2C)
+#define IOMUXC_GPR12                    (0x30)
+#define IOMUXC_GPR13                    (0x34)
+
+
+/* Register Definitions */
+#define PRT_LOG_R_BaseAddress 0x700
+
+/* Register DEBUG_R0 */
+/* Debug Register 0 */
+#define DEBUG_R0 (PRT_LOG_R_BaseAddress + 0x28)
+#define DEBUG_R0_RegisterSize 32
+#define DEBUG_R0_RegisterResetValue 0x0
+#define DEBUG_R0_RegisterResetMask 0xFFFFFFFF
+/* End of Register Definition for DEBUG_R0 */
+
+/* Register DEBUG_R1 */
+/* Debug Register 1 */
+#define DEBUG_R1 (PRT_LOG_R_BaseAddress + 0x2c)
+#define DEBUG_R1_RegisterSize 32
+#define DEBUG_R1_RegisterResetValue 0x0
+#define DEBUG_R1_RegisterResetMask 0xFFFFFFFF
+/* End of Register Definition for DEBUG_R1 */
+
+#define ATU_R_BaseAddress 0x900
+#define PCIE_PL_iATUVR (ATU_R_BaseAddress + 0x0)
+#define PCIE_PL_iATURC1 (ATU_R_BaseAddress + 0x4)
+#define PCIE_PL_iATURC2 (ATU_R_BaseAddress + 0x8)
+#define PCIE_PL_iATURLBA (ATU_R_BaseAddress + 0xC)
+#define PCIE_PL_iATURUBA (ATU_R_BaseAddress + 0x10)
+#define PCIE_PL_iATURLA (ATU_R_BaseAddress + 0x14)
+#define PCIE_PL_iATURLTA (ATU_R_BaseAddress + 0x18)
+#define PCIE_PL_iATURUTA (ATU_R_BaseAddress + 0x1C)
+
+/* GPR1: iomuxc_gpr1_pcie_ref_clk_en(iomuxc_gpr1[16]) */
+#define iomuxc_gpr1_pcie_ref_clk_en		(1 << 16)
+/* GPR1: iomuxc_gpr1_test_powerdown(iomuxc_gpr1_18) */
+#define iomuxc_gpr1_test_powerdown		(1 << 18)
+
+/* GPR12: iomuxc_gpr12_los_level(iomuxc_gpr12[8:4]) */
+#define iomuxc_gpr12_los_level			(0x1F << 4)
+/* GPR12: iomuxc_gpr12_app_ltssm_enable(iomuxc_gpr12[10]) */
+#define iomuxc_gpr12_app_ltssm_enable		(1 << 10)
+/* GPR12: iomuxc_gpr12_device_type(iomuxc_gpr12[15:12]) */
+#define iomuxc_gpr12_device_type		(0xF << 12)
+
+/* GPR8: iomuxc_gpr8_tx_deemph_gen1(iomuxc_gpr8[5:0]) */
+#define iomuxc_gpr8_tx_deemph_gen1		(0x3F << 0)
+/* GPR8: iomuxc_gpr8_tx_deemph_gen2_3p5db(iomuxc_gpr8[11:6]) */
+#define iomuxc_gpr8_tx_deemph_gen2_3p5db	(0x3F << 6)
+/* GPR8: iomuxc_gpr8_tx_deemph_gen2_6db(iomuxc_gpr8[17:12]) */
+#define iomuxc_gpr8_tx_deemph_gen2_6db		(0x3F << 12)
+/* GPR8: iomuxc_gpr8_tx_swing_full(iomuxc_gpr8[24:18]) */
+#define iomuxc_gpr8_tx_swing_full		(0x7F << 18)
+/* GPR8: iomuxc_gpr8_tx_swing_low(iomuxc_gpr8[31:25]) */
+#define iomuxc_gpr8_tx_swing_low		(0x7F << 25)
+
+/* Registers of PHY */
+/* Register PHY_STS_R */
+/* PHY Status Register */
+#define PHY_STS_R (PRT_LOG_R_BaseAddress + 0x110)
+
+/* Register PHY_CTRL_R */
+/* PHY Control Register */
+#define PHY_CTRL_R (PRT_LOG_R_BaseAddress + 0x114)
+
+#define SSP_CR_SUP_DIG_MPLL_OVRD_IN_LO 0x0011
+/* FIELD: RES_ACK_IN_OVRD [15:15]
+// FIELD: RES_ACK_IN [14:14]
+// FIELD: RES_REQ_IN_OVRD [13:13]
+// FIELD: RES_REQ_IN [12:12]
+// FIELD: RTUNE_REQ_OVRD [11:11]
+// FIELD: RTUNE_REQ [10:10]
+// FIELD: MPLL_MULTIPLIER_OVRD [9:9]
+// FIELD: MPLL_MULTIPLIER [8:2]
+// FIELD: MPLL_EN_OVRD [1:1]
+// FIELD: MPLL_EN [0:0]
+*/
+
+#define SSP_CR_SUP_DIG_ATEOVRD 0x0010
+/* FIELD: ateovrd_en [2:2]
+// FIELD: ref_usb2_en [1:1]
+// FIELD: ref_clkdiv2 [0:0]
+*/
+
+#define SSP_CR_LANE0_DIG_RX_OVRD_IN_LO 0x1005
+/* FIELD: RX_LOS_EN_OVRD [13:13]
+// FIELD: RX_LOS_EN [12:12]
+// FIELD: RX_TERM_EN_OVRD [11:11]
+// FIELD: RX_TERM_EN [10:10]
+// FIELD: RX_BIT_SHIFT_OVRD [9:9]
+// FIELD: RX_BIT_SHIFT [8:8]
+// FIELD: RX_ALIGN_EN_OVRD [7:7]
+// FIELD: RX_ALIGN_EN [6:6]
+// FIELD: RX_DATA_EN_OVRD [5:5]
+// FIELD: RX_DATA_EN [4:4]
+// FIELD: RX_PLL_EN_OVRD [3:3]
+// FIELD: RX_PLL_EN [2:2]
+// FIELD: RX_INVERT_OVRD [1:1]
+// FIELD: RX_INVERT [0:0]
+*/
+
+#define SSP_CR_LANE0_DIG_RX_ASIC_OUT 0x100D
+/* FIELD: LOS [2:2]
+// FIELD: PLL_STATE [1:1]
+// FIELD: VALID [0:0]
+*/
+
+/* control bus bit definition */
+#define PCIE_CR_CTL_DATA_LOC 0
+#define PCIE_CR_CTL_CAP_ADR_LOC 16
+#define PCIE_CR_CTL_CAP_DAT_LOC 17
+#define PCIE_CR_CTL_WR_LOC 18
+#define PCIE_CR_CTL_RD_LOC 19
+#define PCIE_CR_STAT_DATA_LOC 0
+#define PCIE_CR_STAT_ACK_LOC 16
+
+/* End of Register Definitions */
+
+#define  PCIE_CONF_BUS(b)		(((b) & 0xFF) << 16)
+#define  PCIE_CONF_DEV(d)		(((d) & 0x1F) << 11)
+#define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
+#define  PCIE_CONF_REG(r)		((r) & ~0x3)
+
+
+/* Taken from PCI specs */
+enum {
+	MemRdWr = 0,
+	MemRdLk = 1,
+	IORdWr = 2,
+	CfgRdWr0 = 4,
+	CfgRdWr1 = 5
+};
+
+
+struct imx_pcie_port {
+	struct device		*dev;
+	u8			index;
+	u8			root_bus_nr;
+	int			interrupt;
+
+	struct resource		*dbi;
+	struct resource		*io;
+	struct resource 	*mem;
+	struct resource 	*root;
+
+	struct regmap		*iomuxc_gpr;
+
+	void __iomem		*root_base;
+	void __iomem		*dbi_base;
+	void __iomem		*io_base;
+	void __iomem		*mem_base;
+	spinlock_t		conf_lock;
+
+	char			io_space_name[16];
+	char			mem_space_name[16];
+
+	struct list_head	next;
+
+	struct clk		*lvds1_sel;
+	struct clk		*lvds1;
+	struct clk		*pcie_ref_125m;
+	struct clk		*pcie_axi;
+	struct clk		*sata_ref;
+
+        unsigned int		pcie_pwr_en;
+        unsigned int		pcie_rst;
+        unsigned int		pcie_wake_up;
+
+	struct rfkill		*rfkill;
+};
+
+static const struct of_device_id pcie_of_match[] = {
+	{
+		.compatible	= "fsl,imx6q-pcie",
+		.data		= NULL,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, pcie_of_match);
+
+static struct list_head pcie_port_list;
+static struct hw_pci imx_pcie;
+
+static int pcie_phy_cr_read(void __iomem *dbi_base, int addr, int *data);
+static int pcie_phy_cr_write(void __iomem *dbi_base, int addr, int data);
+
+
+/* IMX PCIE GPR configure routines */
+static void imx_pcie_clrset(struct imx_pcie_port *pp,
+			    u32 mask, u32 val, u32 reg)
+{
+	u32 tmp;
+	regmap_read(pp->iomuxc_gpr, reg, &tmp);
+	tmp &= ~mask;
+	tmp |= (val & mask);
+	regmap_write(pp->iomuxc_gpr, reg, tmp);
+}
+
+static void change_field(int *in, int start, int end, int val)
+{
+	int mask;
+	mask = ((0xFFFFFFFF << start) ^ (0xFFFFFFFF << (end + 1))) & 0xFFFFFFFF;
+	*in = (*in & ~mask) | (val << start);
+}
+
+
+static struct imx_pcie_port *controller_to_port(int index)
+{
+	struct imx_pcie_port *pp;
+
+	if (index >= imx_pcie.nr_controllers) {
+		pr_err("%d exceeded number of controllers %d\n",
+			index, imx_pcie.nr_controllers);
+		return NULL;
+	}
+
+	list_for_each_entry(pp, &pcie_port_list, next) {
+		if (pp->index == index)
+			return pp;
+	}
+	return NULL;
+}
+
+static struct imx_pcie_port *bus_to_port(int bus)
+{
+	int i;
+	int rbus;
+	struct imx_pcie_port *pp;
+
+	for (i = imx_pcie.nr_controllers - 1 ; i >= 0; i--) {
+		pp = controller_to_port(i);
+		rbus = pp->root_bus_nr;
+		if (rbus != -1 && rbus <= bus)
+			break;
+	}
+
+	return i >= 0 ? pp : NULL;
+}
+
+static int __init imx_pcie_setup(int nr, struct pci_sys_data *sys)
+{
+	struct imx_pcie_port *pp;
+	int ret;
+
+	pp = controller_to_port(nr);
+	if (!pp) {
+		pr_err("unable to find port %d\n", nr);
+		return 0;
+	}
+
+	pp->root_bus_nr = sys->busnr;
+
+	/*
+	 * IORESOURCE_MEM
+	 */
+	snprintf(pp->mem_space_name, sizeof(pp->mem_space_name),
+			"PCIe %d MEM", pp->index);
+
+	pp->mem_space_name[sizeof(pp->mem_space_name) - 1] = 0;
+	pp->mem->name = pp->mem_space_name;
+	pp->mem->flags = IORESOURCE_MEM;
+	ret = request_resource(&iomem_resource, pp->mem);
+	if (ret)
+		dev_err(pp->dev, "Request PCIe Memory resource failed\n");
+	pci_add_resource_offset(&sys->resources, pp->mem, sys->mem_offset);
+
+
+	snprintf(pp->io_space_name, sizeof(pp->io_space_name),
+		 "PCIe %d I/O", pp->index);
+	pp->io_space_name[sizeof(pp->io_space_name) - 1] = 0;
+	pp->io->name = pp->io_space_name;
+	pp->io->flags = IORESOURCE_IO;
+
+	ret = request_resource(&iomem_resource, pp->io);
+	if (ret)
+		dev_err(pp->dev, "Request PCIe IO resource failed\n");
+	pci_add_resource_offset(&sys->resources, pp->io, sys->io_offset);
+
+	/*
+	 * IORESOURCE_IO
+	 */
+	ret = pci_ioremap_io(PCIBIOS_MIN_IO, pp->io->start);
+	if (ret)
+		dev_err(pp->dev, "Request PCIe IO resource failed\n");
+
+	return 1;
+}
+
+static int imx_pcie_link_up(struct platform_device *pdev)
+{
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+	int iterations = 200;
+	u32 rc, ltssm, rx_valid, temp;
+
+	rc = 0;
+	for (iterations = 200; iterations > 0 && !rc; iterations--) {
+		/* link is debug bit 36, debug register 1 starts at bit 32 */
+		rc = readl(pp->dbi_base + DEBUG_R1) & (0x1 << (36 - 32)) ;
+		usleep_range(2000, 3000);
+
+		/* From L0, initiate MAC entry to gen2 if EP/RC supports gen2.
+		 * Wait 2ms (LTSSM timeout is 24ms, PHY lock is ~5us in gen2).
+		 * If (MAC/LTSSM.state == Recovery.RcvrLock)
+		 * && (PHY/rx_valid==0) then pulse PHY/rx_reset. Transition
+		 * to gen2 is stuck
+		 */
+		pcie_phy_cr_read(pp->dbi_base, SSP_CR_LANE0_DIG_RX_ASIC_OUT, &rx_valid);
+		ltssm = readl(pp->dbi_base + DEBUG_R0) & 0x3F;
+		if ((ltssm == 0x0D) && ((rx_valid & 0x01) == 0)) {
+			dev_err(&pdev->dev,
+				"transition to gen2 is stuck, reset PHY!\n");
+			pcie_phy_cr_read(pp->dbi_base, SSP_CR_LANE0_DIG_RX_OVRD_IN_LO, &temp);
+			change_field(&temp, 3, 3, 0x1);
+			change_field(&temp, 5, 5, 0x1);
+			pcie_phy_cr_write(pp->dbi_base, SSP_CR_LANE0_DIG_RX_OVRD_IN_LO,
+					0x0028);
+			usleep_range(2000, 3000);
+			pcie_phy_cr_read(pp->dbi_base, SSP_CR_LANE0_DIG_RX_OVRD_IN_LO, &temp);
+			change_field(&temp, 3, 3, 0x0);
+			change_field(&temp, 5, 5, 0x0);
+			pcie_phy_cr_write(pp->dbi_base, SSP_CR_LANE0_DIG_RX_OVRD_IN_LO,
+					0x0000);
+		}
+
+	}
+
+	if (!rc) {
+		if (iterations <= 0) {
+			dev_err(&pdev->dev,
+				"link up failed, DEBUG_R0:0x%08x, DEBUG_R1:0x%08x  RX_VALID:0x%x!\n",
+				readl(pp->dbi_base + DEBUG_R0),
+				readl(pp->dbi_base + DEBUG_R1),
+				rx_valid);
+			return -ETIMEDOUT;
+		}
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int imx_pcie_regions_setup(struct platform_device *pdev,
+					struct imx_pcie_port *pp)
+{
+	void __iomem *dbi_base = pp->dbi_base;
+	/*
+	 * i.MX6 defines 16MB in the AXI address map for PCIe.
+	 *
+	 * That address space excepted the pcie registers is
+	 * split and defined into different regions by iATU,
+	 * with sizes and offsets as follows:
+	 *
+	 * 0x0100_0000 --- 0x010F_FFFF 1MB IORESOURCE_IO
+	 * 0x0110_0000 --- 0x01EF_FFFF 14MB IORESOURCE_MEM
+	 * 0x01F0_0000 --- 0x01FF_FFFF 1MB Cfg + Registers
+	 */
+
+	/* CMD reg:I/O space, MEM space, and Bus Master Enable */
+	writel(readl(dbi_base + PCI_COMMAND)
+			| PCI_COMMAND_IO
+			| PCI_COMMAND_MEMORY
+			| PCI_COMMAND_MASTER,
+			dbi_base + PCI_COMMAND);
+
+	/* Set the CLASS_REV of RC CFG header to PCI_CLASS_BRIDGE_PCI */
+	writel(readl(dbi_base + PCI_CLASS_REVISION)
+			| (PCI_CLASS_BRIDGE_PCI << 16),
+			dbi_base + PCI_CLASS_REVISION);
+
+	/*
+	 * region0 outbound used to access target cfg
+	 */
+	writel(0, dbi_base + PCIE_PL_iATUVR);
+	writel(pp->root->start, dbi_base + PCIE_PL_iATURLBA);
+	writel(pp->dbi->end, dbi_base + PCIE_PL_iATURLA);
+	writel(0, dbi_base + PCIE_PL_iATURUBA);
+
+	writel(0, dbi_base + PCIE_PL_iATURLTA);
+	writel(0, dbi_base + PCIE_PL_iATURUTA);
+	writel(CfgRdWr0, dbi_base + PCIE_PL_iATURC1);
+	writel((1<<31), dbi_base + PCIE_PL_iATURC2);
+
+	return 0;
+}
+
+
+static int imx_pcie_valid_config(struct imx_pcie_port *pp,
+				struct pci_bus *bus, int devfn)
+{
+	if (bus->number >= 2)
+		return 0;
+
+	if (devfn != 0)
+		return 0;
+
+	return 1;
+}
+
+
+static u32 get_bus_address(struct imx_pcie_port *pp,
+			   struct pci_bus *bus, u32 devfn, int where)
+{
+	u32 va_address;
+	if (bus->number == 0) {
+		va_address = (u32)pp->dbi_base + (where & ~0x3);
+	}
+	else {
+		va_address = (u32)pp->root_base +
+					(PCIE_CONF_BUS(bus->number - 1) +
+					PCIE_CONF_DEV(PCI_SLOT(devfn)) +
+					PCIE_CONF_FUNC(PCI_FUNC(devfn)) +
+					PCIE_CONF_REG(where));
+	}
+	return va_address;
+}
+
+static int imx_pcie_read_config(struct pci_bus *bus, u32 devfn, int where,
+			int size, u32 *val)
+{
+	struct imx_pcie_port *pp = bus_to_port(bus->number);
+	u32 va_address;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (imx_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
+		*val = 0xffffffff;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	va_address = get_bus_address(pp, bus, devfn, where);
+
+	*val = readl((u32 *)va_address);
+
+	if (size == 1)
+		*val = (*val >> (8 * (where & 3))) & 0xFF;
+	else if (size == 2)
+		*val = (*val >> (8 * (where & 3))) & 0xFFFF;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int imx_pcie_write_config(struct pci_bus *bus, u32 devfn,
+			int where, int size, u32 val)
+{
+	struct imx_pcie_port *pp = bus_to_port(bus->number);
+	u32 va_address = 0, mask = 0, tmp = 0;
+	int ret = PCIBIOS_SUCCESSFUL;
+
+	if (!pp) {
+		BUG();
+		return -EINVAL;
+	}
+
+	if (imx_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	va_address = get_bus_address(pp, bus, devfn, where);
+
+	if (size == 4) {
+		writel(val, (u32 *)va_address);
+		goto exit;
+	}
+
+	if (size == 2)
+		mask = ~(0xFFFF << ((where & 0x3) * 8));
+	else if (size == 1)
+		mask = ~(0xFF << ((where & 0x3) * 8));
+	else
+		ret = PCIBIOS_BAD_REGISTER_NUMBER;
+
+	tmp = readl((u32 *)va_address) & mask;
+	tmp |= val << ((where & 0x3) * 8);
+	writel(tmp, (u32 *)va_address);
+exit:
+
+	return ret;
+}
+
+
+
+static struct pci_ops imx_pcie_ops = {
+	.read = imx_pcie_read_config,
+	.write = imx_pcie_write_config,
+};
+
+static struct pci_bus __init *
+imx_pcie_scan_bus(int nr, struct pci_sys_data *sys)
+{
+	struct imx_pcie_port *pp = controller_to_port(nr);
+	if (nr > 1)
+		return NULL;
+        pp->root_bus_nr = sys->busnr;
+
+        return pci_scan_root_bus(NULL, sys->busnr, &imx_pcie_ops, sys,
+                                 &sys->resources);
+}
+
+static int __init imx_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct imx_pcie_port *pp = controller_to_port(0);
+	return pp->interrupt;
+}
+
+static struct hw_pci imx_pci __initdata = {
+	.nr_controllers	= 1,
+	.setup		= imx_pcie_setup,
+	.scan		= imx_pcie_scan_bus,
+	.map_irq	= imx_pcie_map_irq,
+};
+
+/* PHY CR bus acess routines */
+static int pcie_phy_cr_ack_polling(void __iomem *dbi_base, int max_iterations, int exp_val)
+{
+	u32 temp_rd_data, wait_counter = 0;
+
+	do {
+		temp_rd_data = readl(dbi_base + PHY_STS_R);
+		temp_rd_data = (temp_rd_data >> PCIE_CR_STAT_ACK_LOC) & 0x1;
+		wait_counter++;
+	} while ((wait_counter < max_iterations) && (temp_rd_data != exp_val));
+
+	if (temp_rd_data != exp_val)
+		return 0 ;
+	return 1 ;
+}
+
+static int pcie_phy_cr_cap_addr(void __iomem *dbi_base, int addr)
+{
+	u32 temp_wr_data;
+
+	/* write addr */
+	temp_wr_data = addr << PCIE_CR_CTL_DATA_LOC ;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* capture addr */
+	temp_wr_data |= (0x1 << PCIE_CR_CTL_CAP_ADR_LOC);
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 1))
+		return 0;
+
+	/* deassert cap addr */
+	temp_wr_data = addr << PCIE_CR_CTL_DATA_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack de-assetion */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 0))
+		return 0 ;
+
+	return 1 ;
+}
+
+static int pcie_phy_cr_read(void __iomem *dbi_base, int addr , int *data)
+{
+	u32 temp_rd_data, temp_wr_data;
+
+	/*  write addr */
+	/* cap addr */
+	if (!pcie_phy_cr_cap_addr(dbi_base, addr))
+		return 0;
+
+	/* assert rd signal */
+	temp_wr_data = 0x1 << PCIE_CR_CTL_RD_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 1))
+		return 0;
+
+	/* after got ack return data */
+	temp_rd_data = readl(dbi_base + PHY_STS_R);
+	*data = (temp_rd_data & (0xffff << PCIE_CR_STAT_DATA_LOC)) ;
+
+	/* deassert rd signal */
+	temp_wr_data = 0x0;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack de-assetion */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 0))
+		return 0 ;
+
+	return 1 ;
+
+}
+
+static int pcie_phy_cr_write(void __iomem *dbi_base, int addr, int data)
+{
+	u32 temp_wr_data;
+
+	/* write addr */
+	/* cap addr */
+	if (!pcie_phy_cr_cap_addr(dbi_base, addr))
+		return 0 ;
+
+	temp_wr_data = data << PCIE_CR_CTL_DATA_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* capture data */
+	temp_wr_data |= (0x1 << PCIE_CR_CTL_CAP_DAT_LOC);
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 1))
+		return 0 ;
+
+	/* deassert cap data */
+	temp_wr_data = data << PCIE_CR_CTL_DATA_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack de-assetion */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 0))
+		return 0;
+
+	/* assert wr signal */
+	temp_wr_data = 0x1 << PCIE_CR_CTL_WR_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 1))
+		return 0;
+
+	/* deassert wr signal */
+	temp_wr_data = data << PCIE_CR_CTL_DATA_LOC;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	/* wait for ack de-assetion */
+	if (!pcie_phy_cr_ack_polling(dbi_base, 100, 0))
+		return 0;
+
+	temp_wr_data = 0x0 ;
+	writel(temp_wr_data, dbi_base + PHY_CTRL_R);
+
+	return 1;
+}
+
+static int imx_pcie_enable_controller(struct platform_device *pdev)
+{
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+	int ret;
+
+	/* Enable PCIE power */
+	gpio_set_value(pp->pcie_pwr_en, 1);
+
+	imx_pcie_clrset(pp, iomuxc_gpr1_test_powerdown, 0 << 18, IOMUXC_GPR1);
+	imx_pcie_clrset(pp, iomuxc_gpr1_pcie_ref_clk_en, 1 << 16, IOMUXC_GPR1);
+
+	/* Enable clocks */
+	ret = clk_set_parent(pp->lvds1_sel, pp->sata_ref);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to set lvds1 parent: %d\n", ret);
+		return -EINVAL;
+	}
+
+	ret = clk_prepare_enable(pp->pcie_ref_125m);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable pcie_ref_125m: %d\n", ret);
+		return -EINVAL;
+	}
+
+	ret = clk_prepare_enable(pp->lvds1);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable lvds1: %d\n", ret);
+		return -EINVAL;
+	}
+
+	ret = clk_prepare_enable(pp->pcie_axi);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to enable pcie_axi: %d\n", ret);
+		return -EINVAL;
+	}
+
+
+	return 0;
+}
+
+static void card_reset(struct platform_device *pdev)
+{
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+
+	imx_pcie_clrset(pp, iomuxc_gpr1_test_powerdown, 1 << 18, IOMUXC_GPR1);
+	imx_pcie_clrset(pp, iomuxc_gpr12_app_ltssm_enable, 1 << 10, IOMUXC_GPR12);
+	imx_pcie_clrset(pp, iomuxc_gpr1_pcie_ref_clk_en, 0 << 16, IOMUXC_GPR1);
+
+	gpio_set_value(pp->pcie_rst, 0);
+	msleep(100);
+	gpio_set_value(pp->pcie_rst, 1);
+}
+
+static int __init add_pcie_port(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = imx_pcie_link_up(pdev);
+	if (ret) {
+		dev_info(dev, "IMX PCIe port: link down!\n");
+		/* Release the clocks, and disable the power */
+
+		clk_disable(pp->pcie_axi);
+		clk_put(pp->pcie_axi);
+
+		clk_disable(pp->lvds1);
+		clk_put(pp->lvds1);
+
+		clk_put(pp->pcie_ref_125m);
+		clk_put(pp->sata_ref);
+
+		imx_pcie_clrset(pp, iomuxc_gpr1_pcie_ref_clk_en, 0 << 16,
+				IOMUXC_GPR1);
+
+		/* Disable PCIE power */
+		gpio_set_value(pp->pcie_pwr_en, 0);
+
+		imx_pcie_clrset(pp, iomuxc_gpr1_test_powerdown, 1 << 18,
+				IOMUXC_GPR1);
+
+		return ret;
+	}
+
+	dev_info(dev, "IMX PCIe port: link up.\n");
+	pp->index = 0;
+	pp->root_bus_nr = -1;
+	spin_lock_init(&pp->conf_lock);
+	return 0;
+}
+
+
+static int set_pcie_clock_tunings(struct platform_device *pdev)
+{
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+	/* FIXME the field name should be aligned to RM */
+	imx_pcie_clrset(pp, iomuxc_gpr12_app_ltssm_enable, 0 << 10, IOMUXC_GPR12);
+
+	/* configure constant input signal to the pcie ctrl and phy */
+	imx_pcie_clrset(pp, iomuxc_gpr12_device_type, PCI_EXP_TYPE_ROOT_PORT << 12,
+			IOMUXC_GPR12);
+	imx_pcie_clrset(pp, iomuxc_gpr12_los_level, 9 << 4, IOMUXC_GPR12);
+
+	imx_pcie_clrset(pp, iomuxc_gpr8_tx_deemph_gen1, 0 << 0, IOMUXC_GPR8);
+	imx_pcie_clrset(pp, iomuxc_gpr8_tx_deemph_gen2_3p5db, 0 << 6, IOMUXC_GPR8);
+	imx_pcie_clrset(pp, iomuxc_gpr8_tx_deemph_gen2_6db, 20 << 12, IOMUXC_GPR8);
+	imx_pcie_clrset(pp, iomuxc_gpr8_tx_swing_full, 127 << 18, IOMUXC_GPR8);
+	imx_pcie_clrset(pp, iomuxc_gpr8_tx_swing_low, 127 << 25, IOMUXC_GPR8);
+	return 0;
+}
+
+
+static int __init imx_pcie_pltfm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct imx_pcie_port *pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
+	int ret;
+
+	platform_set_drvdata(pdev, pp);
+	pp->dev = &pdev->dev;
+
+        pp->pcie_pwr_en = of_get_named_gpio(pdev->dev.of_node,
+                                "power-enable", 0);
+        if (gpio_is_valid(pp->pcie_pwr_en))
+                devm_gpio_request_one(dev, pp->pcie_pwr_en,
+                                    GPIOF_OUT_INIT_LOW,
+                                    "PCIe power enable");
+
+        pp->pcie_rst = of_get_named_gpio(pdev->dev.of_node,
+                                "pcie-reset", 0);
+        if (gpio_is_valid(pp->pcie_rst))
+                devm_gpio_request_one(dev, pp->pcie_rst,
+                                    GPIOF_OUT_INIT_LOW,
+                                    "PCIe reset");
+
+        pp->pcie_wake_up = of_get_named_gpio(pdev->dev.of_node,
+                                "wake-up", 0);
+        if (gpio_is_valid(pp->pcie_wake_up))
+                devm_gpio_request_one(dev, pp->pcie_wake_up,
+                                    GPIOF_IN,
+                                    "PCIe wake up");
+
+	pp->dbi = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!pp->dbi) {
+		dev_err(dev, "no mmio space\n");
+		return -EINVAL;
+	}
+
+	pp->dbi_base = devm_request_and_ioremap(&pdev->dev, pp->dbi);
+	if (!pp->dbi_base) {
+		pr_err("unable to remap dbi\n");
+		return -ENOMEM;
+	}
+
+
+	pp->io = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!pp->io) {
+		dev_err(dev, "no mmio space\n");
+		return -EINVAL;
+	}
+
+	pp->mem = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!pp->mem) {
+		dev_err(dev, "no mmio space\n");
+		return -EINVAL;
+	}
+
+	pp->root = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	if (!pp->root) {
+		dev_err(dev, "no root memory space\n");
+		return -EINVAL;
+	}
+
+	pp->root_base = devm_request_and_ioremap(&pdev->dev, pp->root);
+	if (!pp->root_base) {
+		dev_err(&pdev->dev, "unable to remap root mem\n");
+		return -ENOMEM;
+	}
+
+
+	pp->interrupt = platform_get_irq(pdev, 0);
+
+
+        /* Setup clocks */
+	pp->lvds1_sel = clk_get(dev, "lvds1_sel");
+	if (IS_ERR(pp->lvds1_sel)) {
+		dev_err(dev,
+			"lvds1_sel clock missing or invalid\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	pp->lvds1 = clk_get(dev, "lvds1");
+	if (IS_ERR(pp->lvds1)) {
+		dev_err(dev,
+			"lvds1 clock select missing or invalid\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	pp->pcie_ref_125m = clk_get(dev, "pcie_ref_125m");
+	if (IS_ERR(pp->pcie_ref_125m)) {
+		dev_err(dev,
+			"pcie_ref_125m clock source missing or invalid\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	pp->pcie_axi = clk_get(dev, "pcie_axi");
+	if (IS_ERR(pp->pcie_axi)) {
+		dev_err(dev, "pcie_axi clock source missing or invalid\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	pp->sata_ref = clk_get(dev, "sata_ref");
+	if (IS_ERR(pp->sata_ref)) {
+		dev_err(dev, "sata_ref clock source missing or invalid\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	pp->iomuxc_gpr = syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
+	if (IS_ERR(pp->iomuxc_gpr)) {
+		dev_err(dev, "unable to find iomuxc registers\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	/* togle the external card's reset */
+	card_reset(pdev);
+
+	/* Enable the pwr, clks and so on */
+	set_pcie_clock_tunings(pdev);
+	ret = imx_pcie_enable_controller(pdev);
+	if (ret)
+		goto err_out;
+
+	usleep_range(3000, 4000);
+	imx_pcie_regions_setup(pdev, pp);
+	usleep_range(3000, 4000);
+
+	/* start link up */
+	imx_pcie_clrset(pp, iomuxc_gpr12_app_ltssm_enable, 1 << 10, IOMUXC_GPR12);
+
+	/* add the pcie port */
+	ret = add_pcie_port(pdev);
+	if (ret)
+		goto err_out;
+
+	pp->index = imx_pcie.nr_controllers;
+	imx_pcie.nr_controllers++;
+	list_add_tail(&pp->next, &pcie_port_list);
+
+	pci_common_init(&imx_pci);
+
+	return 0;
+
+err_out:
+	if (pp->lvds1_sel)
+		clk_put(pp->lvds1_sel);
+	if (pp->lvds1)
+		clk_put(pp->lvds1);
+	if (pp->pcie_ref_125m)
+		clk_put(pp->pcie_ref_125m);
+	if (pp->pcie_axi)
+		clk_put(pp->pcie_axi);
+	if (pp->sata_ref)
+		clk_put(pp->sata_ref);
+	return ret;
+}
+
+static int __exit imx_pcie_pltfm_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct imx_pcie_port *pp = platform_get_drvdata(pdev);
+
+	if (pp->rfkill) {
+		rfkill_unregister(pp->rfkill);
+		rfkill_destroy(pp->rfkill);
+		pp->rfkill = NULL;
+	}
+
+	imx_pcie_clrset(pp, iomuxc_gpr1_pcie_ref_clk_en, 0 << 16, IOMUXC_GPR1);
+	imx_pcie_clrset(pp, iomuxc_gpr1_test_powerdown, 1 << 18, IOMUXC_GPR1);
+	imx_pcie_clrset(pp, iomuxc_gpr12_app_ltssm_enable, 1 << 10, IOMUXC_GPR12);
+
+	/* Release clocks, and disable power  */
+	if (pp->pcie_axi) {
+		clk_disable(pp->pcie_axi);
+		clk_put(pp->pcie_axi);
+	}
+
+	if (pp->lvds1) {
+		clk_disable(pp->lvds1);
+		clk_put(pp->lvds1);
+	}
+
+	if (pp->pcie_ref_125m)
+		clk_put(pp->pcie_ref_125m);
+
+	if (pp->sata_ref)
+		clk_put(pp->sata_ref);
+
+	gpio_set_value(pp->pcie_rst, 0);
+	gpio_set_value(pp->pcie_pwr_en, 0);
+
+	dev_err(dev, "disabled everything\n");
+	msleep(500);
+
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static struct platform_driver imx_pcie_pltfm_driver = {
+	.driver = {
+		.name		= "imx-pcie",
+		.owner		= THIS_MODULE,
+		.of_match_table = pcie_of_match,
+	},
+	.probe		= imx_pcie_pltfm_probe,
+	.remove		= __exit_p(imx_pcie_pltfm_remove),
+};
+
+/*****************************************************************************\
+ *                                                                           *
+ * Driver init/exit                                                          *
+ *                                                                           *
+\*****************************************************************************/
+
+static int __init imx_pcie_drv_init(void)
+{
+	INIT_LIST_HEAD(&pcie_port_list);
+	return platform_driver_register(&imx_pcie_pltfm_driver);
+}
+
+static void __exit imx_pcie_drv_exit(void)
+{
+	platform_driver_unregister(&imx_pcie_pltfm_driver);
+}
+
+module_init(imx_pcie_drv_init);
+module_exit(imx_pcie_drv_exit);
+
+MODULE_DESCRIPTION("i.MX PCIE platform driver");
+MODULE_AUTHOR("Sean Cross <xobs at kosagi.com>");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5



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