[PATCH v5 0/4] PCIE support for i.MX8MQ

[PATCH v5 0/4] PCIE support for i.MX8MQ

[Andrey Smirnov]

Everyone:

This series contains changes I made in order to enable support of PCIE
IP block on i.MX8MQ SoCs.

Changes since [v4]:

 - Collected Reviewed-by from Lucas

 - Replaced ((ARM || ARM64) && COMPILE_TEST) with COMPILE_TEST as per
   suggestion from Rob

Changes since [v3]:

 - Based on feedback from NXP, DIRECT_SPEED_CHANGE quirk was expanded
   to cover both i.MX7 and i.MX8MQ

 - Code setting device type in GPR12 moved to a standalone function

 - Explicit "fsl,controller-id" binding was dropped, replaced by using
   controller physical address to determine logical ID

 - Dropped Reviewed-by from Lucas for patch 4/4 due to the change
   above (haven't heard explicit "yea" for it from him)

Changes since [v2], [fixes]:

 - Incorporated [patch] introducing drvdata

 - i.MX6 PHY operation gating converted to a single patch and to use a
   dedicated flag instead of doing explicit variant check

 - Kconfig entry changed to use ARM64 && ARCH_MXC

 - Dropped FALLTHROUGH annotations

Changes since [v1]:

 - Driver changed to use single "fsl,controller-id" property to
   distinguish between two intances of PCIE IP block

 - All code pertaining to L1SS was dropped to simplify the patch

 - Documented additions to DT bindings

Feedback is welcome!

Thanks,
Andrey Smirnov

[v4] https://lore.kernel.org/linux-arm-kernel/20190104165335.13205-1-andrew.smirnov@gmail.com
[v3] https://lore.kernel.org/linux-arm-kernel/20181218040702.29231-1-andrew.smirnov@gmail.com
[patch] https://patchwork.kernel.org/patch/10712261/
[fixes] https://lore.kernel.org/linux-arm-kernel/20181216230916.22982-1-andrew.smirnov@gmail.com
[v2] https://lore.kernel.org/linux-arm-kernel/20181206073545.10967-1-andrew.smirnov@gmail.com
[v1] https://lore.kernel.org/linux-arm-kernel/20181117181225.10737-1-andrew.smirnov@gmail.com/

Andrey Smirnov (4):
  PCI: imx6: introduce drvdata
  PCI: imx6: Mark PHY functions as i.MX6 specific
  PCI: imx6: Convert DIRECT_SPEED_CHANGE quirk code to use a flag
  PCI: imx6: Add support for i.MX8MQ

 .../bindings/pci/fsl,imx6q-pcie.txt           |   3 +-
 drivers/pci/controller/dwc/Kconfig            |   4 +-
 drivers/pci/controller/dwc/pci-imx6.c         | 150 +++++++++++++++---
 3 files changed, 133 insertions(+), 24 deletions(-)

-- 
2.20.1

[PATCH v5 1/4] PCI: imx6: introduce drvdata

[Andrey Smirnov]

Introduce driver data struct. This will simplify handling of device
specific differences.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
[andrew.smirnov@gmail.com reformatted drvdata, to simplify future diffs]
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/pci/controller/dwc/pci-imx6.c | 56 ++++++++++++++++++---------
 1 file changed, 37 insertions(+), 19 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 25a2b7683e55..efff3d5e9162 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -41,6 +41,10 @@ enum imx6_pcie_variants {
 	IMX7D,
 };
 
+struct imx6_pcie_drvdata {
+	enum imx6_pcie_variants variant;
+};
+
 struct imx6_pcie {
 	struct dw_pcie		*pci;
 	int			reset_gpio;
@@ -53,7 +57,6 @@ struct imx6_pcie {
 	struct reset_control	*pciephy_reset;
 	struct reset_control	*apps_reset;
 	struct reset_control	*turnoff_reset;
-	enum imx6_pcie_variants variant;
 	u32			tx_deemph_gen1;
 	u32			tx_deemph_gen2_3p5db;
 	u32			tx_deemph_gen2_6db;
@@ -66,6 +69,7 @@ struct imx6_pcie {
 	struct device		*pd_pcie;
 	/* power domain for pcie phy */
 	struct device		*pd_pcie_phy;
+	const struct imx6_pcie_drvdata *drvdata;
 };
 
 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
@@ -340,7 +344,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 {
 	struct device *dev = imx6_pcie->pci->dev;
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX7D:
 		reset_control_assert(imx6_pcie->pciephy_reset);
 		reset_control_assert(imx6_pcie->apps_reset);
@@ -382,7 +386,7 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
 	struct device *dev = pci->dev;
 	int ret = 0;
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6SX:
 		ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
 		if (ret) {
@@ -485,7 +489,7 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 					!imx6_pcie->gpio_active_high);
 	}
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX7D:
 		reset_control_deassert(imx6_pcie->pciephy_reset);
 		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
@@ -523,7 +527,7 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 
 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 {
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX7D:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
@@ -645,7 +649,7 @@ static void imx6_pcie_ltssm_enable(struct device *dev)
 {
 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6Q:
 	case IMX6SX:
 	case IMX6QP:
@@ -698,7 +702,7 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
 		tmp |= PORT_LOGIC_SPEED_CHANGE;
 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
 
-		if (imx6_pcie->variant != IMX7D) {
+		if (imx6_pcie->drvdata->variant != IMX7D) {
 			/*
 			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
 			 * from i.MX6 family when no link speed transition
@@ -801,7 +805,7 @@ static void imx6_pcie_ltssm_disable(struct device *dev)
 {
 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6SX:
 	case IMX6QP:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
@@ -827,7 +831,7 @@ static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
 	}
 
 	/* Others poke directly at IOMUXC registers */
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6SX:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
 				IMX6SX_GPR12_PCIE_PM_TURN_OFF,
@@ -857,7 +861,7 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
 	clk_disable_unprepare(imx6_pcie->pcie_phy);
 	clk_disable_unprepare(imx6_pcie->pcie_bus);
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6SX:
 		clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
 		break;
@@ -873,8 +877,8 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
 
 static inline bool imx6_pcie_supports_suspend(struct imx6_pcie *imx6_pcie)
 {
-	return (imx6_pcie->variant == IMX7D ||
-		imx6_pcie->variant == IMX6SX);
+	return (imx6_pcie->drvdata->variant == IMX7D ||
+		imx6_pcie->drvdata->variant == IMX6SX);
 }
 
 static int imx6_pcie_suspend_noirq(struct device *dev)
@@ -939,8 +943,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 	pci->ops = &dw_pcie_ops;
 
 	imx6_pcie->pci = pci;
-	imx6_pcie->variant =
-		(enum imx6_pcie_variants)of_device_get_match_data(dev);
+	imx6_pcie->drvdata = of_device_get_match_data(dev);
 
 	dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
@@ -984,7 +987,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 		return PTR_ERR(imx6_pcie->pcie);
 	}
 
-	switch (imx6_pcie->variant) {
+	switch (imx6_pcie->drvdata->variant) {
 	case IMX6SX:
 		imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
 							   "pcie_inbound_axi");
@@ -1082,11 +1085,26 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
 	imx6_pcie_assert_core_reset(imx6_pcie);
 }
 
+static const struct imx6_pcie_drvdata drvdata[] = {
+	[IMX6Q] = {
+		.variant = IMX6Q,
+	},
+	[IMX6SX] = {
+		.variant = IMX6SX,
+	},
+	[IMX6QP] = {
+		.variant = IMX6QP,
+	},
+	[IMX7D] = {
+		.variant = IMX7D,
+	},
+};
+
 static const struct of_device_id imx6_pcie_of_match[] = {
-	{ .compatible = "fsl,imx6q-pcie",  .data = (void *)IMX6Q,  },
-	{ .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
-	{ .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
-	{ .compatible = "fsl,imx7d-pcie",  .data = (void *)IMX7D,  },
+	{ .compatible = "fsl,imx6q-pcie",  .data = &drvdata[IMX6Q],  },
+	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
+	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
+	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
 	{},
 };
 
-- 
2.20.1

[PATCH v5 2/4] PCI: imx6: Mark PHY functions as i.MX6 specific

[Andrey Smirnov]

PCIE PHY IP block on i.MX7D differs from the one used on i.MX6 family,
so none of the code in current implementation of imx6_setup_phy_mpll()
is applicable.

Tested-by: Trent Piepho <tpiepho@impinj.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
---
 drivers/pci/controller/dwc/pci-imx6.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index efff3d5e9162..c55d93c1187d 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -41,8 +41,11 @@ enum imx6_pcie_variants {
 	IMX7D,
 };
 
+#define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
+
 struct imx6_pcie_drvdata {
 	enum imx6_pcie_variants variant;
+	u32 flags;
 };
 
 struct imx6_pcie {
@@ -256,6 +259,9 @@ static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
 {
 	u32 tmp;
 
+	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
+		return;
+
 	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
 	tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
 		PHY_RX_OVRD_IN_LO_RX_PLL_EN);
@@ -573,6 +579,9 @@ static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
 	int mult, div;
 	u32 val;
 
+	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
+		return 0;
+
 	switch (phy_rate) {
 	case 125000000:
 		/*
@@ -1088,12 +1097,15 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
 static const struct imx6_pcie_drvdata drvdata[] = {
 	[IMX6Q] = {
 		.variant = IMX6Q,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
 	},
 	[IMX6SX] = {
 		.variant = IMX6SX,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
 	},
 	[IMX6QP] = {
 		.variant = IMX6QP,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
 	},
 	[IMX7D] = {
 		.variant = IMX7D,
-- 
2.20.1

[PATCH v5 3/4] PCI: imx6: Convert DIRECT_SPEED_CHANGE quirk code to use a flag

[Andrey Smirnov]

Both i.MX7D and i.MX8MQ have the same behaviour when it comes to
clearing DIRECT_SPEED_CHANGE bit when no speed change occur. To
account for that change the code handling that to use a generic flag
instead of checking IP block variant.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/pci/controller/dwc/pci-imx6.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index c55d93c1187d..75ee0cd7af3b 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -42,6 +42,7 @@ enum imx6_pcie_variants {
 };
 
 #define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
+#define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE	BIT(1)
 
 struct imx6_pcie_drvdata {
 	enum imx6_pcie_variants variant;
@@ -711,7 +712,8 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
 		tmp |= PORT_LOGIC_SPEED_CHANGE;
 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
 
-		if (imx6_pcie->drvdata->variant != IMX7D) {
+		if (imx6_pcie->drvdata->flags &
+		    IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
 			/*
 			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
 			 * from i.MX6 family when no link speed transition
@@ -1097,15 +1099,18 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
 static const struct imx6_pcie_drvdata drvdata[] = {
 	[IMX6Q] = {
 		.variant = IMX6Q,
-		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
+			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
 	},
 	[IMX6SX] = {
 		.variant = IMX6SX,
-		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
+			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
 	},
 	[IMX6QP] = {
 		.variant = IMX6QP,
-		.flags = IMX6_PCIE_FLAG_IMX6_PHY,
+		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
+			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
 	},
 	[IMX7D] = {
 		.variant = IMX7D,
-- 
2.20.1

[PATCH v5 4/4] PCI: imx6: Add support for i.MX8MQ

[Andrey Smirnov]

Add code needed to support i.MX8MQ variant.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Leonard Crestez <leonard.crestez@nxp.com>
Cc: "A.s. Dong" <aisheng.dong@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 .../bindings/pci/fsl,imx6q-pcie.txt           |  3 +-
 drivers/pci/controller/dwc/Kconfig            |  4 +-
 drivers/pci/controller/dwc/pci-imx6.c         | 77 ++++++++++++++++++-
 3 files changed, 79 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
index d514c1f2365f..920ca93870a8 100644
--- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
@@ -9,6 +9,7 @@ Required properties:
 	- "fsl,imx6sx-pcie",
 	- "fsl,imx6qp-pcie"
 	- "fsl,imx7d-pcie"
+	- "fsl,imx8mq-pcie"
 - reg: base address and length of the PCIe controller
 - interrupts: A list of interrupt outputs of the controller. Must contain an
   entry for each entry in the interrupt-names property.
@@ -45,7 +46,7 @@ Additional required properties for imx6sx-pcie:
   PCIE_PHY power domains
 - power-domain-names: Must be "pcie", "pcie_phy"
 
-Additional required properties for imx7d-pcie:
+Additional required properties for imx7d-pcie and imx8mq-pcie:
 - power-domains: Must be set to a phandle pointing to PCIE_PHY power domain
 - resets: Must contain phandles to PCIe-related reset lines exposed by SRC
   IP block
diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 6aafec3fad00..adf7f2061890 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -89,8 +89,8 @@ config PCI_EXYNOS
 	select PCIE_DW_HOST
 
 config PCI_IMX6
-	bool "Freescale i.MX6/7 PCIe controller"
-	depends on SOC_IMX6Q || SOC_IMX7D || (ARM && COMPILE_TEST)
+	bool "Freescale i.MX6/7/8 PCIe controller"
+	depends on SOC_IMX6Q || SOC_IMX7D || (ARM64 && ARCH_MXC) || COMPILE_TEST
 	depends on PCI_MSI_IRQ_DOMAIN
 	select PCIE_DW_HOST
 
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 75ee0cd7af3b..dd9d8732f6ba 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -8,6 +8,7 @@
  * Author: Sean Cross <xobs@kosagi.com>
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/gpio.h>
@@ -32,6 +33,12 @@
 
 #include "pcie-designware.h"
 
+#define IMX8MQ_GPR_PCIE_REF_USE_PAD		BIT(9)
+#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN	BIT(10)
+#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE	BIT(11)
+#define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE	GENMASK(11, 8)
+#define IMX8MQ_PCIE2_BASE_ADDR			0x33c00000
+
 #define to_imx6_pcie(x)	dev_get_drvdata((x)->dev)
 
 enum imx6_pcie_variants {
@@ -39,6 +46,7 @@ enum imx6_pcie_variants {
 	IMX6SX,
 	IMX6QP,
 	IMX7D,
+	IMX8MQ,
 };
 
 #define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
@@ -58,6 +66,7 @@ struct imx6_pcie {
 	struct clk		*pcie_inbound_axi;
 	struct clk		*pcie;
 	struct regmap		*iomuxc_gpr;
+	u32			controller_id;
 	struct reset_control	*pciephy_reset;
 	struct reset_control	*apps_reset;
 	struct reset_control	*turnoff_reset;
@@ -276,6 +285,7 @@ static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
 	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
 }
 
+#ifdef CONFIG_ARM
 /*  Added for PCI abort handling */
 static int imx6q_pcie_abort_handler(unsigned long addr,
 		unsigned int fsr, struct pt_regs *regs)
@@ -309,6 +319,7 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
 
 	return 1;
 }
+#endif
 
 static int imx6_pcie_attach_pd(struct device *dev)
 {
@@ -353,6 +364,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 
 	switch (imx6_pcie->drvdata->variant) {
 	case IMX7D:
+	case IMX8MQ:
 		reset_control_assert(imx6_pcie->pciephy_reset);
 		reset_control_assert(imx6_pcie->apps_reset);
 		break;
@@ -387,10 +399,17 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 	}
 }
 
+static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
+{
+	WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ);
+	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
+}
+
 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
 {
 	struct dw_pcie *pci = imx6_pcie->pci;
 	struct device *dev = pci->dev;
+	unsigned int offset;
 	int ret = 0;
 
 	switch (imx6_pcie->drvdata->variant) {
@@ -421,6 +440,19 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
 		break;
 	case IMX7D:
 		break;
+	case IMX8MQ:
+		offset = imx6_pcie_grp_offset(imx6_pcie);
+		/*
+		 * Set the over ride low and enabled
+		 * make sure that REF_CLK is turned on.
+		 */
+		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
+				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
+				   0);
+		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
+				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
+				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
+		break;
 	}
 
 	return ret;
@@ -497,6 +529,9 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 	}
 
 	switch (imx6_pcie->drvdata->variant) {
+	case IMX8MQ:
+		reset_control_deassert(imx6_pcie->pciephy_reset);
+		break;
 	case IMX7D:
 		reset_control_deassert(imx6_pcie->pciephy_reset);
 		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
@@ -532,9 +567,37 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 	}
 }
 
+static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
+{
+	unsigned int mask, val;
+
+	if (imx6_pcie->drvdata->variant == IMX8MQ &&
+	    imx6_pcie->controller_id == 1) {
+		mask   = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
+		val    = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
+				    PCI_EXP_TYPE_ROOT_PORT);
+	} else {
+		mask = IMX6Q_GPR12_DEVICE_TYPE;
+		val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
+				  PCI_EXP_TYPE_ROOT_PORT);
+	}
+
+	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
+}
+
 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 {
 	switch (imx6_pcie->drvdata->variant) {
+	case IMX8MQ:
+		/*
+		 * TODO: Currently this code assumes external
+		 * oscillator is being used
+		 */
+		regmap_update_bits(imx6_pcie->iomuxc_gpr,
+				   imx6_pcie_grp_offset(imx6_pcie),
+				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
+				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
+		break;
 	case IMX7D:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
@@ -570,8 +633,7 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 		break;
 	}
 
-	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-			IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12);
+	imx6_pcie_configure_type(imx6_pcie);
 }
 
 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
@@ -668,6 +730,7 @@ static void imx6_pcie_ltssm_enable(struct device *dev)
 				   IMX6Q_GPR12_PCIE_CTL_2);
 		break;
 	case IMX7D:
+	case IMX8MQ:
 		reset_control_deassert(imx6_pcie->apps_reset);
 		break;
 	}
@@ -1008,6 +1071,10 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 		}
 		break;
 	case IMX7D:
+	case IMX8MQ:
+		if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
+			imx6_pcie->controller_id = 1;
+
 		imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
 									    "pciephy");
 		if (IS_ERR(imx6_pcie->pciephy_reset)) {
@@ -1115,6 +1182,9 @@ static const struct imx6_pcie_drvdata drvdata[] = {
 	[IMX7D] = {
 		.variant = IMX7D,
 	},
+	[IMX8MQ] = {
+		.variant = IMX8MQ,
+	},
 };
 
 static const struct of_device_id imx6_pcie_of_match[] = {
@@ -1122,6 +1192,7 @@ static const struct of_device_id imx6_pcie_of_match[] = {
 	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
 	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
 	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
+	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } ,
 	{},
 };
 
@@ -1138,6 +1209,7 @@ static struct platform_driver imx6_pcie_driver = {
 
 static int __init imx6_pcie_init(void)
 {
+#ifdef CONFIG_ARM
 	/*
 	 * Since probe() can be deferred we need to make sure that
 	 * hook_fault_code is not called after __init memory is freed
@@ -1147,6 +1219,7 @@ static int __init imx6_pcie_init(void)
 	 */
 	hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
 			"external abort on non-linefetch");
+#endif
 
 	return platform_driver_register(&imx6_pcie_driver);
 }
-- 
2.20.1

Re: [PATCH v5 0/4] PCIE support for i.MX8MQ

[Lorenzo Pieralisi]

On Sat, Jan 12, 2019 at 01:55:57PM -0800, Andrey Smirnov wrote:
> Everyone:
> 
> This series contains changes I made in order to enable support of PCIE
> IP block on i.MX8MQ SoCs.
> 
> Changes since [v4]:
> 
>  - Collected Reviewed-by from Lucas
> 
>  - Replaced ((ARM || ARM64) && COMPILE_TEST) with COMPILE_TEST as per
>    suggestion from Rob
> 
> Changes since [v3]:
> 
>  - Based on feedback from NXP, DIRECT_SPEED_CHANGE quirk was expanded
>    to cover both i.MX7 and i.MX8MQ
> 
>  - Code setting device type in GPR12 moved to a standalone function
> 
>  - Explicit "fsl,controller-id" binding was dropped, replaced by using
>    controller physical address to determine logical ID
> 
>  - Dropped Reviewed-by from Lucas for patch 4/4 due to the change
>    above (haven't heard explicit "yea" for it from him)
> 
> Changes since [v2], [fixes]:
> 
>  - Incorporated [patch] introducing drvdata
> 
>  - i.MX6 PHY operation gating converted to a single patch and to use a
>    dedicated flag instead of doing explicit variant check
> 
>  - Kconfig entry changed to use ARM64 && ARCH_MXC
> 
>  - Dropped FALLTHROUGH annotations
> 
> Changes since [v1]:
> 
>  - Driver changed to use single "fsl,controller-id" property to
>    distinguish between two intances of PCIE IP block
> 
>  - All code pertaining to L1SS was dropped to simplify the patch
> 
>  - Documented additions to DT bindings
> 
> Feedback is welcome!
> 
> Thanks,
> Andrey Smirnov
> 
> [v4] https://lore.kernel.org/linux-arm-kernel/20190104165335.13205-1-andrew.smirnov@gmail.com
> [v3] https://lore.kernel.org/linux-arm-kernel/20181218040702.29231-1-andrew.smirnov@gmail.com
> [patch] https://patchwork.kernel.org/patch/10712261/
> [fixes] https://lore.kernel.org/linux-arm-kernel/20181216230916.22982-1-andrew.smirnov@gmail.com
> [v2] https://lore.kernel.org/linux-arm-kernel/20181206073545.10967-1-andrew.smirnov@gmail.com
> [v1] https://lore.kernel.org/linux-arm-kernel/20181117181225.10737-1-andrew.smirnov@gmail.com/
> 
> Andrey Smirnov (4):
>   PCI: imx6: introduce drvdata
>   PCI: imx6: Mark PHY functions as i.MX6 specific
>   PCI: imx6: Convert DIRECT_SPEED_CHANGE quirk code to use a flag
>   PCI: imx6: Add support for i.MX8MQ
> 
>  .../bindings/pci/fsl,imx6q-pcie.txt           |   3 +-
>  drivers/pci/controller/dwc/Kconfig            |   4 +-
>  drivers/pci/controller/dwc/pci-imx6.c         | 150 +++++++++++++++---
>  3 files changed, 133 insertions(+), 24 deletions(-)

Please read this:

https://lore.kernel.org/linux-pci/20171026223701.GA25649@bhelgaas-glaptop.roam.corp.google.com/

reformat the patches, repost and I will merge them.

Thanks,
Lorenzo