[v5] PCI: Microchip: Add host driver for Microchip PCIe controller

diff --git a/Documentation/devicetree/bindings/pci/microchip-pcie.txt b/Documentation/devicetree/bindings/pci/microchip-pcie.txt
new file mode 100644
index 000000000000..4e226545d3f4
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/microchip-pcie.txt
@@ -0,0 +1,64 @@ 
+* Microchip AXI PCIe Root Port Bridge DT description
+
+Required properties:
+- #address-cells: Address representation for root ports, set to <3>
+- #size-cells: Size representation for root ports, set to <2>
+- #interrupt-cells: specifies the number of cells needed to encode an
+	interrupt source. The value must be 1.
+- compatible: Should contain "microchip,pf-axi-pcie-host"
+- reg: Should contain two address length tuples. 
+	The first is for the internal PCI bridge registers
+	The second is for the PCI config space access registers
+- device_type: must be "pci"
+- interrupts: Should contain AXI PCIe interrupt
+- interrupt-map-mask,
+- interrupt-map: standard PCI properties to define the mapping of the
+	PCI interface to interrupt numbers.
+- ranges: ranges for the PCI memory regions (I/O space region is not
+	supported by hardware)
+	Please refer to the standard PCI bus binding document for a more
+	detailed explanation
+
+Optional properties for PolarFire:
+- bus-range: PCI bus numbers covered
+
+Interrupt controller child node
++++++++++++++++++++++++++++++++
+Required properties:
+- interrupt-controller: identifies the node as an interrupt controller
+- #address-cells: specifies the number of cells needed to encode an
+	address. The value must be 0.
+- #interrupt-cells: specifies the number of cells needed to encode an
+	interrupt source. The value must be 1.
+
+NOTE:
+The core provides a single interrupt for both INTx/MSI messages. So,
+create an interrupt controller node to support 'interrupt-map' DT
+functionality.  The driver will create an IRQ domain for this map, decode
+the four INTx interrupts in ISR and route them to this domain.
+
+
+Example:
+++++++++
+AloeVera:
+
+	pcie: pcie@2030000000 {
+		#address-cells = <3>;
+		#size-cells = <2>;
+		#interrupt-cells = <1>;
+		compatible = "microchip,pf-axi-pcie-host-1.0";
+		device_type = "pci";
+		bus-range = <0x01 0x7f>;
+		interrupt-map = <0 0 0 1 &pcie 1>,
+				<0 0 0 2 &pcie 2>,
+				<0 0 0 3 &pcie 3>,
+				<0 0 0 4 &pcie 4>;
+		interrupt-map-mask = <0 0 0 7>;
+		interrupt-parent = <&L4>;
+		interrupts = <32>;
+		ranges = <0x3000000 0 0x40000000 0x0 0x40000000 0x0 0x20000000>;
+		reg = <0x20 0x30000000 0x0 0x4000000>,	/* internal registers */
+			<0x20 0x0 0x0 0x100000>;	/* config space access registers */
+		reg-names = "control", "apb";
+		interrupt-controller;
+	};
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 6671946dbf66..7141d26e668c 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -280,5 +280,15 @@  config VMD
 	  To compile this driver as a module, choose M here: the
 	  module will be called vmd.
 
+config PCIE_MICROCHIP
+	bool "Microchip AXI PCIe host bridge support"
+	depends on PCI_MSI && OF
+	select PCI_MSI_IRQ_DOMAIN
+	select GENERIC_MSI_IRQ_DOMAIN
+	select PC
+	help
+	  Say Y here if you want kernel to support the Microchip AXI PCIe
+	  Host Bridge driver.
+
 source "drivers/pci/controller/dwc/Kconfig"
 endmenu
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index d56a507495c5..cb5ef5ccf1f6 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -28,6 +28,7 @@  obj-$(CONFIG_PCIE_ROCKCHIP_HOST) += pcie-rockchip-host.o
 obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
 obj-$(CONFIG_PCIE_MOBIVEIL) += pcie-mobiveil.o
 obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o
+obj-$(CONFIG_PCIE_MICROCHIP) += pcie-microchip.o
 obj-$(CONFIG_VMD) += vmd.o
 # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
 obj-y				+= dwc/
diff --git a/drivers/pci/controller/pcie-microchip.c b/drivers/pci/controller/pcie-microchip.c
new file mode 100644
index 000000000000..5ee30a449e11
--- /dev/null
+++ b/drivers/pci/controller/pcie-microchip.c
@@ -0,0 +1,786 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Microchip AXI PCIe Bridge host controller driver
+ *
+ * Copyright (c) 2018 - 2019 Microchip Corporation. All rights reserved.
+ *
+ * Author: Daire McNamara <daire.mcnamara@microchip.com>
+ *
+ * Based on:
+ *	pcie-rcar.c
+ *	pcie-xilinx.c
+ *	pcie-altera.c
+ */
+
+#include <linux/irqchip/chained_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/module.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/msi.h>
+
+#include "../pci.h"
+
+/* ECAM definitions */
+#define ECAM_BUS_NUM_SHIFT			20
+#define ECAM_DEV_NUM_SHIFT			12
+
+/* Number of MSI IRQs */
+#define MICROCHIP_NUM_MSI_IRQS			4
+#define MICROCHIP_NUM_MSI_IRQS_CODED		2
+
+/* PCIe Bridge Phy and Controller Phy offsets */
+#define MICROCHIP_PCIE0_BRIDGE_ADDR		0x00004000u
+#define MICROCHIP_PCIE0_CTRL_ADDR		0x00006000u
+
+#define MICROCHIP_PCIE1_BRIDGE_ADDR		0x00008000u
+#define MICROCHIP_PCIE1_CTRL_ADDR		0x0000a000u
+
+/* PCIe Controller Phy Regs */
+#define MICROCHIP_SEC_ERROR_INT			0x28
+#define  SEC_ERROR_INT_TX_RAM_SEC_ERR_INT	GENMASK(3, 0)
+#define  SEC_ERROR_INT_RX_RAM_SEC_ERR_INT	GENMASK(7, 4)
+#define  SEC_ERROR_INT_PCIE2AXI_RAM_SEC_ERR_INT	GENMASK(11, 8)
+#define  SEC_ERROR_INT_AXI2PCIE_RAM_SEC_ERR_INT	GENMASK(15, 12)
+#define MICROCHIP_SEC_ERROR_INT_MASK		0x2c
+#define MICROCHIP_DED_ERROR_INT			0x30
+#define  DED_ERROR_INT_TX_RAM_DED_ERR_INT	GENMASK(3, 0)
+#define  DED_ERROR_INT_RX_RAM_DED_ERR_INT	GENMASK(7, 4)
+#define  DED_ERROR_INT_PCIE2AXI_RAM_DED_ERR_INT	GENMASK(11, 8)
+#define  DED_ERROR_INT_AXI2PCIE_RAM_DED_ERR_INT	GENMASK(15, 12)
+#define MICROCHIP_DED_ERROR_INT_MASK		0x34
+#define MICROCHIP_ECC_CONTROL			0x38
+#define  ECC_CONTROL_AXI2PCIE_RAM_ECC_BYPASS	BIT(27)
+#define  ECC_CONTROL_PCIE2AXI_RAM_ECC_BYPASS	BIT(26)
+#define  ECC_CONTROL_RX_RAM_ECC_BYPASS		BIT(25)
+#define  ECC_CONTROL_TX_RAM_ECC_BYPASS		BIT(24)
+#define MICROCHIP_LTSSM_STATE			0x5c
+#define  LTSSM_L0_STATE				0x10
+#define MICROCHIP_PCIE_EVENT_INT		0x14c
+#define  PCIE_EVENT_INT_L2_EXIT_INT		BIT(0)
+#define  PCIE_EVENT_INT_HOTRST_EXIT_INT		BIT(1)
+#define  PCIE_EVENT_INT_DLUP_EXIT_INT		BIT(2)
+#define  PCIE_EVENT_INT_L2_EXIT_INT_MASK	BIT(16)
+#define  PCIE_EVENT_INT_HOTRST_EXIT_INT_MASK	BIT(17)
+#define  PCIE_EVENT_INT_DLUP_EXIT_INT_MASK	BIT(18)
+
+/* PCIe Bridge Phy Regs */
+#define MICROCHIP_PCIE_PCI_IDS_DW1		0x9c
+
+/* PCIe Config space MSI capability structure */
+#define MICROCHIP_MSI_CAP_CTRL			0xe0u
+#define  MSI_ENABLE				(0x01u << 16)
+#define  MSI_CAP_MULTI				\
+	 (MICROCHIP_NUM_MSI_IRQS_CODED << 17)
+#define  MSI_ENABLE_MULTI			\
+	 (MICROCHIP_NUM_MSI_IRQS_CODED << 20)
+#define MICROCHIP_MSI_MSG_LO_ADDR		0xe4u
+#define MICROCHIP_MSI_MSG_HI_ADDR		0xe8u
+#define MICROCHIP_MSI_MSG_DATA			0xf0u
+
+#define MICROCHIP_IMASK_LOCAL			0x180
+#define  PCIE_LOCAL_INT_ENABLE			0x0f000000u
+#define  PCI_INTS				0x0f000000u
+#define  PM_MSI_INT_SHIFT			24
+#define  PCIE_ENABLE_MSI			0x10000000u
+#define  MSI_INT				0x10000000u
+#define  MSI_INT_SHIFT				28
+#define MICROCHIP_ISTATUS_LOCAL			0x184
+#define MICROCHIP_IMASK_HOST			0x188
+#define MICROCHIP_ISTATUS_HOST			0x18c
+#define MICROCHIP_ISTATUS_MSI			0x194
+
+/* PCIe Master table init defines */
+#define MICROCHIP_ATR0_PCIE_WIN0_SRCADDR_31_12	0x600u
+#define  ATR0_PCIE_WIN0_SIZE			0x1f
+#define  ATR0_PCIE_WIN0_SIZE_SHIFT		1
+#define MICROCHIP_ATR0_PCIE_WIN0_SRCADDR_63_32	0x604u
+
+/* PCIe AXI slave table init defines */
+#define MICROCHIP_ATR0_AXI4_SLV0_SRCADDR_PARAM	0x800u
+#define  ATR_SIZE_SHIFT				1
+#define  ATR_IMPL_ENABLE			1
+#define MICROCHIP_ATR0_AXI4_SLV0_SRC_ADDR	0x804u
+#define MICROCHIP_ATR0_AXI4_SLV0_TRSL_ADDR_LSB	0x808u
+#define MICROCHIP_ATR0_AXI4_SLV0_TRSL_ADDR_UDW	0x80cu
+#define MICROCHIP_ATR0_AXI4_SLV0_TRSL_PARAM	0x810u
+#define  PCIE_TX_RX_INTERFACE			0x00000000u
+#define  PCIE_CONFIG_INTERFACE			0x00000001u
+#define  ATR0_AXI4_SLV_SIZE			32
+
+struct microchip_msi {
+	struct mutex		lock;		/* protect used bitmap */
+	struct irq_domain	*msi_domain;
+	struct irq_domain	*dev_domain;
+	u32			num_vectors;
+	phys_addr_t		vector_phy;
+	DECLARE_BITMAP(used, MICROCHIP_NUM_MSI_IRQS);
+};
+
+/**
+ * struct microchip_pcie - PCIe port information
+ * @base_addr: IO Mapped Register Base
+ * @irq: Interrupt number
+ * @root_busno: Root Bus number
+ * @dev: Device pointer
+ * @leg_domain: Legacy IRQ domain pointer
+ */
+struct microchip_pcie {
+	struct platform_device *pdev;
+	void __iomem *base_addr;
+	void __iomem *bridge_base_addr;
+	void __iomem *ctrl_base_addr;
+	u64 hw_base_addr;
+	u32 atr_sz;
+	int bridgeno;
+	u32 irq;
+	u8 root_busno;
+	struct irq_domain *intx_domain;
+	raw_spinlock_t intx_mask_lock;
+	struct microchip_msi msi;
+};
+
+static inline u32 pcie_readl(struct microchip_pcie *pcie, const u32 reg)
+{
+	return readl_relaxed(pcie->base_addr + reg);
+}
+
+static inline void pcie_writel(struct microchip_pcie *pcie,
+			       const u32 val, const u32 reg)
+{
+	writel_relaxed(val, pcie->base_addr + reg);
+}
+
+static void microchip_pcie_enable(struct microchip_pcie *pcie)
+{
+	u32 enb;
+
+	enb = readl(pcie->bridge_base_addr + MICROCHIP_LTSSM_STATE);
+	enb |= LTSSM_L0_STATE;
+	writel(enb, pcie->bridge_base_addr + MICROCHIP_LTSSM_STATE);
+}
+
+static bool microchip_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
+{
+	struct microchip_pcie *pcie = bus->sysdata;
+
+	/* Only one device down on each root port */
+	if (bus->number == pcie->root_busno && (PCI_SLOT(devfn) > 0))
+		return false;
+
+	/*
+	 * Do not read more than one device on the bus directly
+	 * attached
+	 */
+	if (bus->primary == pcie->root_busno && devfn > 0)
+		return false;
+
+	return true;
+}
+
+/*
+ * microchip_pcie_map_bus - routine to get the configuration base
+ * of either root port or endpoint
+ */
+static void __iomem *microchip_pcie_map_bus(struct pci_bus *bus,
+					    unsigned int devfn, int where)
+{
+	struct microchip_pcie *pcie = bus->sysdata;
+	int relbus;
+
+	if (!microchip_pcie_valid_device(bus, devfn))
+		return NULL;
+
+	relbus = (bus->number << ECAM_BUS_NUM_SHIFT) |
+		(devfn << ECAM_DEV_NUM_SHIFT);
+
+	return pcie->base_addr + relbus + where;
+}
+
+static struct pci_ops microchip_pcie_ops = {
+	.map_bus = microchip_pcie_map_bus,
+	.read = pci_generic_config_read,
+	.write = pci_generic_config_write,
+};
+
+static void microchip_pcie_isr(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct microchip_pcie *pcie = irq_desc_get_handler_data(desc);
+	struct device *dev = &pcie->pdev->dev;
+	struct microchip_msi *msi = &pcie->msi;
+	unsigned long status;
+	unsigned long intx_status;
+	unsigned long msi_status;
+	unsigned long msi_data;
+	u32 bit;
+	u32 virq;
+
+	/*
+	 * The core provides a single interrupt for both INTx/MSI messages.
+	 * So we'll read both INTx and MSI status
+	 */
+	chained_irq_enter(chip, desc);
+
+	status = readl(pcie->bridge_base_addr + MICROCHIP_ISTATUS_LOCAL);
+	while (status & (PCI_INTS | MSI_INT)) {
+		intx_status = (status & PCI_INTS) >> PM_MSI_INT_SHIFT;
+		for_each_set_bit(bit, &intx_status, PCI_NUM_INTX) {
+			virq = irq_find_mapping(pcie->intx_domain, bit + 1);
+			if (virq)
+				generic_handle_irq(virq);
+			else
+				dev_err_ratelimited(dev,
+						    "bad INTx IRQ %d\n",
+						    bit);
+
+			/* clear that interrupt bit */
+			writel(1 << (bit + PM_MSI_INT_SHIFT),
+			       pcie->bridge_base_addr +
+			       MICROCHIP_ISTATUS_LOCAL);
+		}
+
+		msi_status = (status & MSI_INT);
+		if (msi_status) {
+			msi_status = readl(pcie->bridge_base_addr +
+					   MICROCHIP_ISTATUS_MSI);
+			msi_data = pcie_readl(pcie, MICROCHIP_MSI_MSG_DATA);
+			for_each_set_bit(bit, &msi_status, msi->num_vectors) {
+				virq = irq_find_mapping(msi->dev_domain, bit);
+				if (virq)
+					generic_handle_irq(virq);
+				else
+					dev_err_ratelimited(dev,
+							    "bad MSI IRQ %d\n",
+							    bit);
+
+				/* clear that MSI interrupt bit */
+				writel((1 << bit), pcie->bridge_base_addr +
+				       MICROCHIP_ISTATUS_MSI);
+			}
+			/* clear the ISTATUS MSI bit */
+			writel(1 << MSI_INT_SHIFT, pcie->bridge_base_addr +
+			       MICROCHIP_ISTATUS_LOCAL);
+		}
+
+		status = readl(pcie->bridge_base_addr +
+			       MICROCHIP_ISTATUS_LOCAL);
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static int microchip_pcie_parse_dt(struct microchip_pcie *pcie)
+{
+	struct platform_device *pdev = pcie->pdev;
+	struct device *dev = &pcie->pdev->dev;
+	struct device_node *node = dev->of_node;
+	struct microchip_msi *msi = &pcie->msi;
+	struct resource res;
+	const char *type;
+	resource_size_t size;
+	int ret;
+	void __iomem *axi_base_addr;
+
+	type = of_get_property(node, "device_type", NULL);
+	if (!type || strcmp(type, "pci")) {
+		dev_err(dev, "invalid \"device_type\" %s\n", type);
+		return -EINVAL;
+	}
+
+	/* Only supporting bridge 1 */
+	pcie->bridgeno = 1;
+
+	pcie->root_busno = 0;
+
+	ret = of_address_to_resource(node, 0, &res);
+	if (ret) {
+		dev_err(dev, "missing \"reg\" property\n");
+		return ret;
+	}
+
+	pcie->base_addr = devm_pci_remap_cfg_resource(dev, &res);
+	if (IS_ERR(pcie->base_addr))
+		return PTR_ERR(pcie->base_addr);
+
+	pcie->hw_base_addr = res.start;
+
+	size = resource_size(&res);
+	pcie->atr_sz = find_first_bit((const unsigned long *)&size, 64) - 1;
+
+	ret = of_address_to_resource(node, 1, &res);
+	if (ret) {
+		dev_err(dev, "missing \"reg\" property\n");
+		return ret;
+	}
+
+	axi_base_addr = devm_ioremap_resource(dev, &res);
+	if (IS_ERR(axi_base_addr))
+		return PTR_ERR(axi_base_addr);
+
+	if (pcie->bridgeno == 0) {
+		pcie->bridge_base_addr = axi_base_addr
+			+ MICROCHIP_PCIE0_BRIDGE_ADDR;
+		pcie->ctrl_base_addr = axi_base_addr
+			+ MICROCHIP_PCIE0_CTRL_ADDR;
+	} else {
+		pcie->bridge_base_addr = axi_base_addr
+			+ MICROCHIP_PCIE1_BRIDGE_ADDR;
+		pcie->ctrl_base_addr = axi_base_addr
+			+ MICROCHIP_PCIE1_CTRL_ADDR;
+	}
+
+	if (of_property_read_u64(node, "vector-slave", &msi->vector_phy))
+		msi->vector_phy = 0x190;
+
+	if (of_property_read_u32(node, "num-vectors", &msi->num_vectors))
+		msi->num_vectors = 32;
+
+	pcie->irq = platform_get_irq(pdev, 0);
+	if (pcie->irq < 0) {
+		dev_err(dev, "unable to request IRQ%d\n", pcie->irq);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static void microchip_pcie_enable_msi(struct microchip_pcie *pcie)
+{
+	struct microchip_msi *msi = &pcie->msi;
+	u32 msg_ctrl = pcie_readl(pcie, MICROCHIP_MSI_CAP_CTRL);
+
+	msg_ctrl |= MSI_ENABLE_MULTI | MSI_CAP_MULTI | MSI_ENABLE;
+	pcie_writel(pcie, msg_ctrl, MICROCHIP_MSI_CAP_CTRL);
+	pcie_writel(pcie, lower_32_bits(msi->vector_phy),
+		    MICROCHIP_MSI_MSG_LO_ADDR);
+	pcie_writel(pcie, upper_32_bits(msi->vector_phy),
+		    MICROCHIP_MSI_MSG_HI_ADDR);
+}
+
+static int microchip_host_init(struct microchip_pcie *pcie)
+{
+	u32 val;
+
+	microchip_pcie_enable(pcie);
+
+	val = ECC_CONTROL_AXI2PCIE_RAM_ECC_BYPASS
+		| ECC_CONTROL_PCIE2AXI_RAM_ECC_BYPASS
+		| ECC_CONTROL_RX_RAM_ECC_BYPASS
+		| ECC_CONTROL_TX_RAM_ECC_BYPASS;
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_ECC_CONTROL);
+
+	val = PCIE_EVENT_INT_L2_EXIT_INT
+		| PCIE_EVENT_INT_HOTRST_EXIT_INT
+		| PCIE_EVENT_INT_DLUP_EXIT_INT
+		| PCIE_EVENT_INT_L2_EXIT_INT_MASK
+		| PCIE_EVENT_INT_HOTRST_EXIT_INT_MASK
+		| PCIE_EVENT_INT_DLUP_EXIT_INT_MASK;
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_PCIE_EVENT_INT);
+
+	val = SEC_ERROR_INT_TX_RAM_SEC_ERR_INT
+		| SEC_ERROR_INT_RX_RAM_SEC_ERR_INT
+		| SEC_ERROR_INT_PCIE2AXI_RAM_SEC_ERR_INT
+		| SEC_ERROR_INT_AXI2PCIE_RAM_SEC_ERR_INT;
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_SEC_ERROR_INT);
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_SEC_ERROR_INT_MASK);
+
+	val = DED_ERROR_INT_TX_RAM_DED_ERR_INT
+		| DED_ERROR_INT_RX_RAM_DED_ERR_INT
+		| DED_ERROR_INT_PCIE2AXI_RAM_DED_ERR_INT
+		| DED_ERROR_INT_AXI2PCIE_RAM_DED_ERR_INT;
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_DED_ERROR_INT);
+	writel(val, pcie->ctrl_base_addr + MICROCHIP_DED_ERROR_INT_MASK);
+
+	writel(0, pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	writel(GENMASK(31, 0),
+	       pcie->bridge_base_addr + MICROCHIP_ISTATUS_LOCAL);
+	writel(0, pcie->bridge_base_addr + MICROCHIP_IMASK_HOST);
+	writel(GENMASK(31, 0), pcie->bridge_base_addr + MICROCHIP_ISTATUS_HOST);
+
+	/* Configure Address Translation Table 0 for PCIe config space */
+	writel(PCIE_CONFIG_INTERFACE,
+	       pcie->bridge_base_addr + MICROCHIP_ATR0_AXI4_SLV0_TRSL_PARAM);
+
+	val = lower_32_bits(pcie->hw_base_addr) |
+		(pcie->atr_sz << ATR_SIZE_SHIFT) | ATR_IMPL_ENABLE;
+	writel(val, pcie->bridge_base_addr +
+		MICROCHIP_ATR0_AXI4_SLV0_SRCADDR_PARAM);
+
+	val  = lower_32_bits(pcie->hw_base_addr);
+	writel(val, pcie->bridge_base_addr +
+		MICROCHIP_ATR0_AXI4_SLV0_TRSL_ADDR_LSB);
+
+	val = readl(pcie->bridge_base_addr +
+		MICROCHIP_ATR0_PCIE_WIN0_SRCADDR_31_12);
+	val |= (ATR0_PCIE_WIN0_SIZE << ATR0_PCIE_WIN0_SIZE_SHIFT);
+
+	writel(val, pcie->bridge_base_addr +
+		MICROCHIP_ATR0_PCIE_WIN0_SRCADDR_31_12);
+
+	writel(0, pcie->bridge_base_addr +
+		MICROCHIP_ATR0_PCIE_WIN0_SRCADDR_63_32);
+
+	val = readl(pcie->bridge_base_addr + MICROCHIP_PCIE_PCI_IDS_DW1);
+	val &= 0xffff;
+	val |= (PCI_CLASS_BRIDGE_PCI << 16);
+	writel(val, pcie->bridge_base_addr + MICROCHIP_PCIE_PCI_IDS_DW1);
+
+	/* setup bus numbers */
+	val = pcie_readl(pcie, PCI_PRIMARY_BUS);
+	val &= 0xff000000;
+	val |= 0x00ff0100;
+	pcie_writel(pcie, val, PCI_PRIMARY_BUS);
+
+	/* setup MSI hardware registers */
+	microchip_pcie_enable_msi(pcie);
+
+	val = PCIE_ENABLE_MSI | PCIE_LOCAL_INT_ENABLE;
+	writel(val, pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+
+	return 0;
+}
+
+static void microchip_mask_intx_irq(struct irq_data *data)
+{
+	struct irq_desc *desc = irq_to_desc(data->irq);
+	struct microchip_pcie *pcie;
+	unsigned long flags;
+	u32 mask, val;
+
+	pcie = irq_desc_get_chip_data(desc);
+	mask = PCIE_LOCAL_INT_ENABLE;
+	raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
+	val = readl(pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	val &= ~mask;
+	writel(val, pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
+}
+
+static void microchip_unmask_intx_irq(struct irq_data *data)
+{
+	struct irq_desc *desc = irq_to_desc(data->irq);
+	struct microchip_pcie *pcie;
+	unsigned long flags;
+	u32 mask, val;
+
+	pcie = irq_desc_get_chip_data(desc);
+	mask = PCIE_LOCAL_INT_ENABLE;
+	raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
+	val = readl(pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	val |= mask;
+	writel(val, pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
+}
+
+static struct irq_chip microchip_intx_irq_chip = {
+	.name = "microchip_pcie:intx",
+	.irq_enable = microchip_unmask_intx_irq,
+	.irq_disable = microchip_mask_intx_irq,
+	.irq_mask = microchip_mask_intx_irq,
+	.irq_unmask = microchip_unmask_intx_irq,
+};
+
+/* routine to setup the INTx related data */
+static int microchip_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+				   irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &microchip_intx_irq_chip,
+				 handle_simple_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+/* INTx domain operations structure */
+static const struct irq_domain_ops intx_domain_ops = {
+	.map = microchip_pcie_intx_map,
+};
+
+static struct irq_chip microchip_msi_irq_chip = {
+	.name = "Microchip PCIe MSI",
+	.irq_mask = pci_msi_mask_irq,
+	.irq_unmask = pci_msi_unmask_irq,
+};
+
+static struct msi_domain_info microchip_msi_domain_info = {
+	.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+			MSI_FLAG_PCI_MSIX),
+	.chip = &microchip_msi_irq_chip,
+};
+
+static void microchip_compose_msi_msg(struct irq_data *data,
+				      struct msi_msg *msg)
+{
+	struct microchip_pcie *pcie = irq_data_get_irq_chip_data(data);
+	phys_addr_t addr = pcie->msi.vector_phy;
+
+	msg->address_lo = lower_32_bits(addr);
+	msg->address_hi = upper_32_bits(addr);
+	msg->data = data->hwirq;
+
+	dev_dbg(&pcie->pdev->dev, "msi#%x address_hi %#x address_lo %#x\n",
+		(int)data->hwirq, msg->address_hi, msg->address_lo);
+}
+
+static int microchip_msi_set_affinity(struct irq_data *irq_data,
+				      const struct cpumask *mask, bool force)
+{
+	return -EINVAL;
+}
+
+static struct irq_chip microchip_msi_bottom_irq_chip = {
+	.name		= "Microchip MSI",
+	.irq_compose_msi_msg	= microchip_compose_msi_msg,
+	.irq_set_affinity	= microchip_msi_set_affinity,
+};
+
+static int microchip_irq_msi_domain_alloc(struct irq_domain *domain,
+					  unsigned int virq,
+					  unsigned int nr_irqs, void *args)
+{
+	struct microchip_pcie *pcie = domain->host_data;
+	struct microchip_msi *msi = &pcie->msi;
+	unsigned long bit;
+	u32 reg;
+
+	WARN_ON(nr_irqs != 1);
+	mutex_lock(&msi->lock);
+	bit = find_first_zero_bit(msi->used, msi->num_vectors);
+	if (bit >= msi->num_vectors) {
+		mutex_unlock(&msi->lock);
+		return -ENOSPC;
+	}
+
+	set_bit(bit, msi->used);
+	mutex_unlock(&msi->lock);
+
+	irq_domain_set_info(domain, virq, bit, &microchip_msi_bottom_irq_chip,
+			    domain->host_data, handle_simple_irq,
+			    NULL, NULL);
+
+	/* Enable MSI interrupts */
+	reg = readl(pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+	reg |= PCIE_ENABLE_MSI;
+	writel(reg, pcie->bridge_base_addr + MICROCHIP_IMASK_LOCAL);
+
+	return 0;
+}
+
+static void microchip_irq_msi_domain_free(struct irq_domain *domain,
+					  unsigned int virq,
+					  unsigned int nr_irqs)
+{
+	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+	struct microchip_pcie *pcie = irq_data_get_irq_chip_data(d);
+	struct microchip_msi *msi = &pcie->msi;
+
+	mutex_lock(&msi->lock);
+
+	if (!test_bit(d->hwirq, msi->used))
+		dev_err(&pcie->pdev->dev, "trying to free unused MSI%lu\n",
+			d->hwirq);
+	else
+		__clear_bit(d->hwirq, msi->used);
+
+	mutex_unlock(&msi->lock);
+}
+
+static const struct irq_domain_ops msi_domain_ops = {
+	.alloc	= microchip_irq_msi_domain_alloc,
+	.free	= microchip_irq_msi_domain_free,
+};
+
+static int microchip_allocate_msi_domains(struct microchip_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+	struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
+	struct microchip_msi *msi = &pcie->msi;
+
+	mutex_init(&pcie->msi.lock);
+
+	msi->dev_domain = irq_domain_add_linear(NULL, msi->num_vectors,
+						&msi_domain_ops,
+						pcie);
+	if (!msi->dev_domain) {
+		dev_err(dev, "failed to create IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	msi->msi_domain =
+		pci_msi_create_irq_domain(fwnode,
+					  &microchip_msi_domain_info,
+					  msi->dev_domain);
+	if (!msi->msi_domain) {
+		dev_err(dev, "failed to create MSI domain\n");
+		irq_domain_remove(msi->dev_domain);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int microchip_pcie_init_irq_domains(struct microchip_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+	struct device_node *node = dev->of_node;
+	int ret;
+
+	/* Setup INTx */
+	pcie->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
+						  &intx_domain_ops,
+						  pcie);
+	if (!pcie->intx_domain) {
+		dev_err(dev, "failed to get an INTx IRQ domain\n");
+		return -ENOMEM;
+	}
+	raw_spin_lock_init(&pcie->intx_mask_lock);
+
+	/* setup MSI */
+	ret = microchip_allocate_msi_domains(pcie);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int microchip_pcie_probe(struct platform_device *pdev)
+{
+	struct microchip_pcie *pcie;
+	struct pci_bus *bus;
+	struct pci_bus *child;
+	struct pci_host_bridge *bridge;
+	struct device *dev = &pdev->dev;
+	struct resource_entry *win;
+	int ret;
+	resource_size_t size;
+	u32 index = 1;
+	u32 atr_sz;
+	u32 val;
+
+	if (!dev->of_node)
+		return -ENODEV;
+
+	/* allocate the PCIe port */
+	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
+	if (!bridge)
+		return -ENOMEM;
+
+	pcie = pci_host_bridge_priv(bridge);
+
+	pcie->pdev = pdev;
+
+	ret = microchip_pcie_parse_dt(pcie);
+	if (ret) {
+		dev_err(dev, "parsing devicetree failed, ret %x\n", ret);
+		return ret;
+	}
+
+	irq_set_chained_handler_and_data(pcie->irq, microchip_pcie_isr, pcie);
+
+	/*
+	 * configure all inbound and outbound windows and prepare
+	 * for config access
+	 */
+	ret = microchip_host_init(pcie);
+	if (ret) {
+		dev_err(dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	ret = pci_parse_request_of_pci_ranges(dev, &bridge->windows,
+					      &bridge->dma_ranges, NULL);
+	if (ret) {
+		dev_err(dev, "failed to parse pci ranges\n");
+		return ret;
+	}
+
+	resource_list_for_each_entry(win, &bridge->windows) {
+		if (resource_type(win->res) == IORESOURCE_MEM)
+			;
+		else if (resource_type(win->res) == IORESOURCE_IO)
+			;
+		else
+			continue;
+
+		size = resource_size(win->res);
+		atr_sz =
+			find_first_bit((const unsigned long *)&size, 64)
+				- 1;
+
+		/* Configure Address Translation Table index for PCIe
+		 * mem space
+		 */
+		writel(PCIE_TX_RX_INTERFACE,
+		       pcie->bridge_base_addr
+		       + (index * ATR0_AXI4_SLV_SIZE)
+		       + MICROCHIP_ATR0_AXI4_SLV0_TRSL_PARAM);
+
+		val = lower_32_bits(win->res->start) |
+			(atr_sz << ATR_SIZE_SHIFT) | ATR_IMPL_ENABLE;
+
+		writel(val, pcie->bridge_base_addr
+			+ (index * ATR0_AXI4_SLV_SIZE)
+			+ MICROCHIP_ATR0_AXI4_SLV0_SRCADDR_PARAM);
+
+		val = lower_32_bits(win->res->start - win->offset);
+		writel(val,
+		       pcie->bridge_base_addr
+		       + (index * ATR0_AXI4_SLV_SIZE)
+		       + MICROCHIP_ATR0_AXI4_SLV0_TRSL_ADDR_LSB);
+
+		index++;
+	}
+
+	/* initialise the IRQ domains */
+	ret = microchip_pcie_init_irq_domains(pcie);
+	if (ret) {
+		dev_err(dev, "failed creating IRQ domains\n");
+		return ret;
+	}
+
+	/* Initialize bridge */
+	bridge->dev.parent = dev;
+	bridge->sysdata = pcie;
+	bridge->busnr = pcie->root_busno;
+	bridge->ops = &microchip_pcie_ops;
+	bridge->map_irq = of_irq_parse_and_map_pci;
+	bridge->swizzle_irq = pci_common_swizzle;
+
+	/* setup the kernel resources for the newly added PCIe root bus */
+	ret = pci_scan_root_bus_bridge(bridge);
+	if (ret < 0)
+		return ret;
+
+	bus = bridge->bus;
+
+	pci_assign_unassigned_bus_resources(bus);
+	list_for_each_entry(child, &bus->children, node)
+		pcie_bus_configure_settings(child);
+	pci_bus_add_devices(bus);
+
+	return 0;
+}
+
+static const struct of_device_id microchip_pcie_of_match[] = {
+	{ .compatible = "microchip,pf-axi-pcie-host-1.0", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, microchip_pcie_of_match)
+
+static struct platform_driver microchip_pcie_driver = {
+	.probe = microchip_pcie_probe,
+	.driver = {
+		.name = "microchip-pcie",
+		.of_match_table = microchip_pcie_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+
+builtin_platform_driver(microchip_pcie_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Microchip PCIe host controller driver");
+MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");