[PATCH 7/7] pci: Add i.MX6 pcie support

Sascha Hauer s.hauer at pengutronix.de
Mon Mar 16 23:38:51 PDT 2015


Based on the corresponding kernel driver with changes to make it
work on barebox.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 arch/arm/mach-imx/Kconfig      |   1 +
 drivers/pci/Kconfig            |   7 +
 drivers/pci/Makefile           |   1 +
 drivers/pci/pci-imx6.c         | 612 +++++++++++++++++++++++++++++++++++++++++
 include/mfd/imx6q-iomuxc-gpr.h |   8 +
 5 files changed, 629 insertions(+)
 create mode 100644 drivers/pci/pci-imx6.c

diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index c62cea8..fe6c679 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -174,6 +174,7 @@ config ARCH_IMX6
 	select CPU_V7
 	select PINCTRL_IMX_IOMUX_V3
 	select COMMON_CLK_OF_PROVIDER
+	select HW_HAS_PCI
 
 config ARCH_IMX6SX
 	bool
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index bd24ce0..1c45a1c 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -40,6 +40,13 @@ config PCI_TEGRA
 	select OF_PCI
 	select PCI
 
+config PCI_IMX6
+	bool "Freescale i.MX6 PCIe controller"
+	depends on ARCH_IMX6
+	select PCIE_DW
+	select OF_PCI
+	select PCI
+
 endmenu
 
 endif
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 3240abd..ce5d0e2 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -10,3 +10,4 @@ CPPFLAGS += $(ccflags-y)
 obj-$(CONFIG_PCI_MVEBU)	+= pci-mvebu.o pci-mvebu-phy.o
 obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
 obj-$(CONFIG_PCIE_DW) += pcie-designware.o
+obj-$(CONFIG_PCI_IMX6) += pci-imx6.o
diff --git a/drivers/pci/pci-imx6.c b/drivers/pci/pci-imx6.c
new file mode 100644
index 0000000..eaa5f0e
--- /dev/null
+++ b/drivers/pci/pci-imx6.c
@@ -0,0 +1,612 @@
+/*
+ * PCIe host controller driver for Freescale i.MX6 SoCs
+ *
+ * Copyright (C) 2013 Kosagi
+ *		http://www.kosagi.com
+ *
+ * Author: Sean Cross <xobs at kosagi.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 <common.h>
+#include <clock.h>
+#include <malloc.h>
+#include <io.h>
+#include <init.h>
+#include <gpio.h>
+#include <asm/mmu.h>
+#include <of_gpio.h>
+#include <linux/clk.h>
+#include <linux/kernel.h>
+#include <of_address.h>
+#include <of_pci.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/reset.h>
+#include <linux/sizes.h>
+#include <mfd/imx6q-iomuxc-gpr.h>
+
+#include <mach/imx6-regs.h>
+
+#include "pcie-designware.h"
+
+#define to_imx6_pcie(x)	container_of(x, struct imx6_pcie, pp)
+
+struct imx6_pcie {
+	int			reset_gpio;
+	struct clk		*pcie_bus;
+	struct clk		*pcie_phy;
+	struct clk		*pcie;
+	struct pcie_port	pp;
+	void __iomem		*iomuxc_gpr;
+	void __iomem		*mem_base;
+};
+
+/* PCIe Root Complex registers (memory-mapped) */
+#define PCIE_RC_LCR				0x7c
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1	0x1
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2	0x2
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK	0xf
+
+/* PCIe Port Logic registers (memory-mapped) */
+#define PL_OFFSET 0x700
+#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
+#define PCIE_PL_PFLR_LINK_STATE_MASK		(0x3f << 16)
+#define PCIE_PL_PFLR_FORCE_LINK			(1 << 15)
+#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
+#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING	(1 << 29)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP		(1 << 4)
+
+#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
+#define PCIE_PHY_CTRL_DATA_LOC 0
+#define PCIE_PHY_CTRL_CAP_ADR_LOC 16
+#define PCIE_PHY_CTRL_CAP_DAT_LOC 17
+#define PCIE_PHY_CTRL_WR_LOC 18
+#define PCIE_PHY_CTRL_RD_LOC 19
+
+#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
+#define PCIE_PHY_STAT_ACK_LOC 16
+
+#define PCIE_LINK_WIDTH_SPEED_CONTROL	0x80C
+#define PORT_LOGIC_SPEED_CHANGE		(0x1 << 17)
+
+/* PHY registers (not memory-mapped) */
+#define PCIE_PHY_RX_ASIC_OUT 0x100D
+
+#define PHY_RX_OVRD_IN_LO 0x1005
+#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
+#define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
+
+static int pcie_phy_poll_ack(void __iomem *dbi_base, int exp_val)
+{
+	u32 val;
+	u32 max_iterations = 10;
+	u32 wait_counter = 0;
+
+	do {
+		val = readl(dbi_base + PCIE_PHY_STAT);
+		val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
+		wait_counter++;
+
+		if (val == exp_val)
+			return 0;
+
+		udelay(1);
+	} while (wait_counter < max_iterations);
+
+	return -ETIMEDOUT;
+}
+
+static int pcie_phy_wait_ack(void __iomem *dbi_base, int addr)
+{
+	u32 val;
+	int ret;
+
+	val = addr << PCIE_PHY_CTRL_DATA_LOC;
+	writel(val, dbi_base + PCIE_PHY_CTRL);
+
+	val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
+	writel(val, dbi_base + PCIE_PHY_CTRL);
+
+	ret = pcie_phy_poll_ack(dbi_base, 1);
+	if (ret)
+		return ret;
+
+	val = addr << PCIE_PHY_CTRL_DATA_LOC;
+	writel(val, dbi_base + PCIE_PHY_CTRL);
+
+	ret = pcie_phy_poll_ack(dbi_base, 0);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
+static int pcie_phy_read(void __iomem *dbi_base, int addr , int *data)
+{
+	u32 val, phy_ctl;
+	int ret;
+
+	ret = pcie_phy_wait_ack(dbi_base, addr);
+	if (ret)
+		return ret;
+
+	/* assert Read signal */
+	phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
+	writel(phy_ctl, dbi_base + PCIE_PHY_CTRL);
+
+	ret = pcie_phy_poll_ack(dbi_base, 1);
+	if (ret)
+		return ret;
+
+	val = readl(dbi_base + PCIE_PHY_STAT);
+	*data = val & 0xffff;
+
+	/* deassert Read signal */
+	writel(0x00, dbi_base + PCIE_PHY_CTRL);
+
+	ret = pcie_phy_poll_ack(dbi_base, 0);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int pcie_phy_write(void __iomem *dbi_base, int addr, int data)
+{
+	u32 var;
+	int ret;
+
+	/* write addr */
+	/* cap addr */
+	ret = pcie_phy_wait_ack(dbi_base, addr);
+	if (ret)
+		return ret;
+
+	var = data << PCIE_PHY_CTRL_DATA_LOC;
+	writel(var, dbi_base + PCIE_PHY_CTRL);
+
+	/* capture data */
+	var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
+	writel(var, dbi_base + PCIE_PHY_CTRL);
+
+	ret = pcie_phy_poll_ack(dbi_base, 1);
+	if (ret)
+		return ret;
+
+	/* deassert cap data */
+	var = data << PCIE_PHY_CTRL_DATA_LOC;
+	writel(var, dbi_base + PCIE_PHY_CTRL);
+
+	/* wait for ack de-assertion */
+	ret = pcie_phy_poll_ack(dbi_base, 0);
+	if (ret)
+		return ret;
+
+	/* assert wr signal */
+	var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
+	writel(var, dbi_base + PCIE_PHY_CTRL);
+
+	/* wait for ack */
+	ret = pcie_phy_poll_ack(dbi_base, 1);
+	if (ret)
+		return ret;
+
+	/* deassert wr signal */
+	var = data << PCIE_PHY_CTRL_DATA_LOC;
+	writel(var, dbi_base + PCIE_PHY_CTRL);
+
+	/* wait for ack de-assertion */
+	ret = pcie_phy_poll_ack(dbi_base, 0);
+	if (ret)
+		return ret;
+
+	writel(0x0, dbi_base + PCIE_PHY_CTRL);
+
+	return 0;
+}
+
+static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
+{
+	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	u32 val, gpr1, gpr12;
+
+	/*
+	 * If the bootloader already enabled the link we need some special
+	 * handling to get the core back into a state where it is safe to
+	 * touch it for configuration.  As there is no dedicated reset signal
+	 * wired up for MX6QDL, we need to manually force LTSSM into "detect"
+	 * state before completely disabling LTSSM, which is a prerequisite
+	 * for core configuration.
+	 *
+	 * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
+	 * indication that the bootloader activated the link.
+	 */
+	gpr1 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+	gpr12 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+
+	if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
+	    (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
+		val = readl(pp->dbi_base + PCIE_PL_PFLR);
+		val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
+		val |= PCIE_PL_PFLR_FORCE_LINK;
+		writel(val, pp->dbi_base + PCIE_PL_PFLR);
+
+		gpr12 &= ~IMX6Q_GPR12_PCIE_CTL_2;
+		writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+	}
+
+	gpr1 |= IMX6Q_GPR1_PCIE_TEST_PD;
+	writel(gpr1, imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+
+	gpr1 &= ~IMX6Q_GPR1_PCIE_REF_CLK_EN;
+	writel(gpr1, imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+
+	return 0;
+}
+
+static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
+{
+	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	int ret;
+	u32 gpr1;
+
+	ret = clk_enable(imx6_pcie->pcie_phy);
+	if (ret)
+		goto err_pcie_phy;
+
+	ret = clk_enable(imx6_pcie->pcie_bus);
+	if (ret)
+		goto err_pcie_bus;
+
+	ret = clk_enable(imx6_pcie->pcie);
+	if (ret)
+		goto err_pcie;
+
+	/* power up core phy and enable ref clock */
+	gpr1 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+	gpr1 &= ~IMX6Q_GPR1_PCIE_TEST_PD;
+	writel(gpr1, imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+	/*
+	 * the async reset input need ref clock to sync internally,
+	 * when the ref clock comes after reset, internal synced
+	 * reset time is too short, cannot meet the requirement.
+	 * add one ~10us delay here.
+	 */
+	udelay(10);
+	gpr1 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+	gpr1 |= IMX6Q_GPR1_PCIE_REF_CLK_EN;
+	writel(gpr1, imx6_pcie->iomuxc_gpr + IOMUXC_GPR1);
+
+	/* allow the clocks to stabilize */
+	udelay(200);
+
+	/* Some boards don't have PCIe reset GPIO. */
+	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+		gpio_set_value(imx6_pcie->reset_gpio, 0);
+		mdelay(100);
+		gpio_set_value(imx6_pcie->reset_gpio, 1);
+	}
+	return 0;
+
+err_pcie:
+	clk_disable(imx6_pcie->pcie_bus);
+err_pcie_bus:
+	clk_disable(imx6_pcie->pcie_phy);
+err_pcie_phy:
+	return ret;
+
+}
+
+static void imx6_pcie_init_phy(struct pcie_port *pp)
+{
+	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	u32 gpr12, gpr8;
+
+	gpr12 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+	gpr12 &= ~IMX6Q_GPR12_PCIE_CTL_2;
+	writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+
+	/* configure constant input signal to the pcie ctrl and phy */
+	gpr12 &= ~IMX6Q_GPR12_DEVICE_TYPE;
+	gpr12 |= PCI_EXP_TYPE_ROOT_PORT << 12;
+	writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+
+	gpr12 &= ~IMX6Q_GPR12_LOS_LEVEL;
+	gpr12 |= 9 << 4;
+	writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+
+	gpr8 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+	gpr8 &= ~IMX6Q_GPR8_TX_DEEMPH_GEN1;
+	writel(gpr8, imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+
+	gpr8 &= ~IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB;
+	writel(gpr8, imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+
+	gpr8 &= ~IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB;
+	gpr8 |= 20 << 12;
+	writel(gpr8, imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+
+	gpr8 &= ~IMX6Q_GPR8_TX_SWING_FULL;
+	gpr8 |= 127 << 18;
+	writel(gpr8, imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+
+	gpr8 &= ~IMX6Q_GPR8_TX_SWING_LOW;
+	gpr8 |= 127 << 25;
+	writel(gpr8, imx6_pcie->iomuxc_gpr + IOMUXC_GPR8);
+}
+
+static int imx6_pcie_wait_for_link(struct pcie_port *pp)
+{
+	uint64_t start = get_time_ns();
+
+	while (1) {
+		if (dw_pcie_link_up(pp))
+			return 0;
+
+		if (!is_timeout(start, SECOND))
+			continue;
+
+		dev_err(pp->dev, "phy link never came up\n");
+		dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+			readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+			readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+		return -EINVAL;
+	}
+}
+
+static int imx6_pcie_start_link(struct pcie_port *pp)
+{
+	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	uint32_t tmp;
+	int ret;
+	u32 gpr12;
+	u64 start;
+
+	/*
+	 * Force Gen1 operation when starting the link.  In case the link is
+	 * started in Gen2 mode, there is a possibility the devices on the
+	 * bus will not be detected at all.  This happens with PCIe switches.
+	 */
+	tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+	tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+	tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
+	writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+	/* Start LTSSM. */
+	gpr12 = readl(imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+	gpr12 |= IMX6Q_GPR12_PCIE_CTL_2;
+	writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12);
+
+	ret = imx6_pcie_wait_for_link(pp);
+	if (ret)
+		return ret;
+
+	/* Allow Gen2 mode after the link is up. */
+	tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+	tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+	tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
+	writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+	/*
+	 * Start Directed Speed Change so the best possible speed both link
+	 * partners support can be negotiated.
+	 */
+	tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+	tmp |= PORT_LOGIC_SPEED_CHANGE;
+	writel(tmp, pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+
+	start = get_time_ns();
+	while (!is_timeout(start, SECOND)) {
+		tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+		/* Test if the speed change finished. */
+		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+			break;
+	}
+
+	/* Make sure link training is finished as well! */
+	if (tmp & PORT_LOGIC_SPEED_CHANGE)
+		ret = -EINVAL;
+	else
+		ret = imx6_pcie_wait_for_link(pp);
+
+	if (ret) {
+		dev_err(pp->dev, "Failed to bring link up!\n");
+	} else {
+		tmp = readl(pp->dbi_base + 0x80);
+		dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+	}
+
+	return ret;
+}
+
+static void imx6_pcie_host_init(struct pcie_port *pp)
+{
+	imx6_pcie_assert_core_reset(pp);
+
+	imx6_pcie_init_phy(pp);
+
+	imx6_pcie_deassert_core_reset(pp);
+
+	dw_pcie_setup_rc(pp);
+
+	imx6_pcie_start_link(pp);
+}
+
+static void imx6_pcie_reset_phy(struct pcie_port *pp)
+{
+	uint32_t temp;
+
+	pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+	temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+		 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+	pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+
+	udelay(2000);
+
+	pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+	temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+		  PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+	pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+}
+
+static int imx6_pcie_link_up(struct pcie_port *pp)
+{
+	u32 rc, debug_r0, rx_valid;
+	int count = 5;
+
+	/*
+	 * Test if the PHY reports that the link is up and also that the LTSSM
+	 * training finished. There are three possible states of the link when
+	 * this code is called:
+	 * 1) The link is DOWN (unlikely)
+	 *     The link didn't come up yet for some reason. This usually means
+	 *     we have a real problem somewhere. Reset the PHY and exit. This
+	 *     state calls for inspection of the DEBUG registers.
+	 * 2) The link is UP, but still in LTSSM training
+	 *     Wait for the training to finish, which should take a very short
+	 *     time. If the training does not finish, we have a problem and we
+	 *     need to inspect the DEBUG registers. If the training does finish,
+	 *     the link is up and operating correctly.
+	 * 3) The link is UP and no longer in LTSSM training
+	 *     The link is up and operating correctly.
+	 */
+	while (1) {
+		rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1);
+		if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_UP))
+			break;
+		if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING))
+			return 1;
+		if (!count--)
+			break;
+		dev_dbg(pp->dev, "Link is up, but still in training\n");
+		/*
+		 * Wait a little bit, then re-check if the link finished
+		 * the training.
+		 */
+		udelay(1000);
+	}
+	/*
+	 * 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_read(pp->dbi_base, PCIE_PHY_RX_ASIC_OUT, &rx_valid);
+	debug_r0 = readl(pp->dbi_base + PCIE_PHY_DEBUG_R0);
+
+	if (rx_valid & 0x01)
+		return 0;
+
+	if ((debug_r0 & 0x3f) != 0x0d)
+		return 0;
+
+	dev_err(pp->dev, "transition to gen2 is stuck, reset PHY!\n");
+	dev_dbg(pp->dev, "debug_r0=%08x debug_r1=%08x\n", debug_r0, rc);
+
+	imx6_pcie_reset_phy(pp);
+
+	return 0;
+}
+
+static struct pcie_host_ops imx6_pcie_host_ops = {
+	.link_up = imx6_pcie_link_up,
+	.host_init = imx6_pcie_host_init,
+};
+
+static int __init imx6_add_pcie_port(struct pcie_port *pp,
+			struct device_d *dev)
+{
+	int ret;
+
+	pp->root_bus_nr = -1;
+	pp->ops = &imx6_pcie_host_ops;
+
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __init imx6_pcie_probe(struct device_d *dev)
+{
+	struct imx6_pcie *imx6_pcie;
+	struct pcie_port *pp;
+	struct device_node *np = dev->device_node;
+	int ret;
+
+	imx6_pcie = xzalloc(sizeof(*imx6_pcie));
+	if (!imx6_pcie)
+		return -ENOMEM;
+
+	pp = &imx6_pcie->pp;
+	pp->dev = dev;
+
+	pp->dbi_base = dev_request_mem_region(dev, 0);
+	if (IS_ERR(pp->dbi_base))
+		return PTR_ERR(pp->dbi_base);
+
+	/* Fetch GPIOs */
+	imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+		ret = gpio_request_one(imx6_pcie->reset_gpio,
+					    GPIOF_OUT_INIT_LOW, "PCIe reset");
+		if (ret) {
+			dev_err(dev, "unable to get reset gpio\n");
+			return ret;
+		}
+	}
+
+	/* Fetch clocks */
+	imx6_pcie->pcie_phy = clk_get(dev, "pcie_phy");
+	if (IS_ERR(imx6_pcie->pcie_phy)) {
+		dev_err(dev, "pcie_phy clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie_phy);
+	}
+
+	imx6_pcie->pcie_bus = clk_get(dev, "pcie_bus");
+	if (IS_ERR(imx6_pcie->pcie_bus)) {
+		dev_err(dev, "pcie_bus clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie_bus);
+	}
+
+	imx6_pcie->pcie = clk_get(dev, "pcie");
+	if (IS_ERR(imx6_pcie->pcie)) {
+		dev_err(dev, "pcie clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie);
+	}
+
+	/* Grab GPR config register range */
+	imx6_pcie->iomuxc_gpr = IOMEM(MX6_IOMUXC_BASE_ADDR);
+
+	ret = imx6_add_pcie_port(pp, dev);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static struct of_device_id imx6_pcie_of_match[] = {
+	{ .compatible = "fsl,imx6q-pcie", },
+	{},
+};
+
+static struct driver_d imx6_pcie_driver = {
+	.name = "imx6-pcie",
+	.of_compatible = DRV_OF_COMPAT(imx6_pcie_of_match),
+	.probe = imx6_pcie_probe,
+};
+device_platform_driver(imx6_pcie_driver);
+
+MODULE_AUTHOR("Sean Cross <xobs at kosagi.com>");
+MODULE_DESCRIPTION("Freescale i.MX6 PCIe host controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/mfd/imx6q-iomuxc-gpr.h b/include/mfd/imx6q-iomuxc-gpr.h
index 24993ff..a7ef1c8 100644
--- a/include/mfd/imx6q-iomuxc-gpr.h
+++ b/include/mfd/imx6q-iomuxc-gpr.h
@@ -259,6 +259,12 @@
 #define IMX6Q_GPR7_IPU2_ID10_RD_QOS_MASK	(0xf << 24)
 #define IMX6Q_GPR7_IPU2_ID11_RD_QOS_MASK	(0xf << 28)
 
+#define IMX6Q_GPR8_TX_SWING_LOW			(0x7f << 25)
+#define IMX6Q_GPR8_TX_SWING_FULL		(0x7f << 18)
+#define IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB		(0x3f << 12)
+#define IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB		(0x3f << 6)
+#define IMX6Q_GPR8_TX_DEEMPH_GEN1		(0x3f << 0)
+
 #define IMX6Q_GPR9_TZASC2_BYP			BIT(1)
 #define IMX6Q_GPR9_TZASC1_BYP			BIT(0)
 
@@ -291,7 +297,9 @@
 #define IMX6Q_GPR12_ARMP_AHB_CLK_EN		BIT(26)
 #define IMX6Q_GPR12_ARMP_ATB_CLK_EN		BIT(25)
 #define IMX6Q_GPR12_ARMP_APB_CLK_EN		BIT(24)
+#define IMX6Q_GPR12_DEVICE_TYPE			(0xf << 12)
 #define IMX6Q_GPR12_PCIE_CTL_2			BIT(10)
+#define IMX6Q_GPR12_LOS_LEVEL			(0x1f << 4)
 
 #define IMX6Q_GPR13_SDMA_STOP_REQ		BIT(30)
 #define IMX6Q_GPR13_CAN2_STOP_REQ		BIT(29)
-- 
2.1.4




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