[PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[Bharat Kumar Gogada]

Adding PCIe Root Port driver for Xilinx PCIe NWL bridge IP.

Signed-off-by: Bharat Kumar Gogada <bharatku@xilinx.com>
Signed-off-by: Ravi Kiran Gummaluri <rgummal@xilinx.com>
---
Added MSI domain implementation for handling MSI interrupts
Added implementation for chained irq handlers
Added legacy domain for handling legacy interrupts
Added child node for handling legacy interrupt
---
 .../devicetree/bindings/pci/xilinx-nwl-pcie.txt    |   71 ++
 drivers/pci/host/Kconfig                           |    9 +
 drivers/pci/host/Makefile                          |    1 +
 drivers/pci/host/pcie-xilinx-nwl.c                 | 1066 ++++++++++++++++++++
 4 files changed, 1147 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
 create mode 100644 drivers/pci/host/pcie-xilinx-nwl.c

diff --git a/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt b/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
new file mode 100644
index 0000000..d64fc97
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
@@ -0,0 +1,71 @@
+* Xilinx NWL PCIe Root Port Bridge DT description
+
+Required properties:
+- compatible: Should contain "xlnx,nwl-pcie-2.11"
+- #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.
+- reg: Should contain Bridge, PCIe Controller registers location,
+	configuration sapce, and length
+- reg-names: Must include the following entries:
+	"breg": bridge registers
+	"pcireg": PCIe controller registers
+	"cfg": configuration space region
+- device_type: must be "pci"
+- interrupts: Should contain NWL PCIe interrupt
+- interrupt-names: Must include the following entries:
+	"misc": interrupt asserted when miscellaneous is recieved
+	"intx": interrupt that is asserted when an legacy interrupt is received
+	"msi_1, msi_0": interrupt asserted when msi is recieved
+- interrupt-map-mask and 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
+- msi-controller: indicates that this is MSI controller node
+- msi-parent:  MSI parent of the root complex itself
+- pcie_intc: Interrupt controller device node for Legacy interrupts
+	- interrupt-controller: identifies the node as an interrupt controller
+	- #interrupt-cells: should be set to 1
+	- #address-cells: specifies the number of cells needed to encode an
+		address. The value must be 0.
+
+
+Example:
+++++++++
+
+nwl_pcie: pcie@fd0e0000 {
+	#address-cells = <3>;
+	#size-cells = <2>;
+	compatible = "xlnx,nwl-pcie-2.11";
+	#interrupt-cells = <1>;
+	msi-controller;
+	device_type = "pci";
+	interrupt-parent = <&gic>;
+	interrupts = < 0 118 4
+		       0 116 4
+		       0 115 4          // MSI_1 [63...32]
+		       0 114 4 >;       // MSI_0 [31...0]
+	interrupt-names = "misc", "intx", "msi_1", "msi_0";
+	interrupt-map-mask = <0x0 0x0 0x0 0x7>;
+	interrupt-map = <0x0 0x0 0x0 0x1 &pcie_intc 0x1
+			 0x0 0x0 0x0 0x2 &pcie_intc 0x2
+			 0x0 0x0 0x0 0x3 &pcie_intc 0x3
+			 0x0 0x0 0x0 0x4 &pcie_intc 0x4>;
+
+	msi-parent = <&nwl_pcie>;
+	reg = <0x0 0xfd0e0000 0x1000
+	       0x0 0xfd480000 0x1000
+	       0x0 0xE0000000 0x1000000>;
+	reg-names = "breg", "pcireg", "cfg";
+	ranges = <0x02000000 0x00000000 0xE1000000 0x00000000 0xE1000000 0 0x0F000000>;
+
+	pcie_intc: legacy-interrupt-controller {
+		interrupt-controller;
+		#address-cells = <0>;
+		#interrupt-cells = <1>;
+	};
+
+};
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index c132bdd..33bbddb 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -15,6 +15,15 @@ config PCI_MVEBU
	depends on ARCH_MVEBU || ARCH_DOVE
	depends on OF

+config PCIE_XILINX_NWL
+	bool "NWL PCIe Core"
+	depends on ARCH_ZYNQMP
+	help
+	 Say 'Y' here if you want kernel to support for Xilinx
+	 NWL PCIe controller. The controller can act as Root Port
+	 or End Point. The current option selection will only
+	 support root port enabling.
+
 config PCIE_DW
	bool

diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 140d66f..6a56df7 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
 obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
 obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
 obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
+obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
 obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
 obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
 obj-$(CONFIG_PCI_LAYERSCAPE) += pci-layerscape.o
diff --git a/drivers/pci/host/pcie-xilinx-nwl.c b/drivers/pci/host/pcie-xilinx-nwl.c
new file mode 100644
index 0000000..11c29bd
--- /dev/null
+++ b/drivers/pci/host/pcie-xilinx-nwl.c
@@ -0,0 +1,1066 @@
+/*
+ * PCIe host controller driver for NWL PCIe Bridge
+ * Based on pcie-xilinx.c, pci-tegra.c
+ *
+ * (C) Copyright 2014 - 2015, Xilinx, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/irqchip/chained_irq.h>
+
+/* Bridge core config registers */
+#define BRCFG_PCIE_RX0			0x00000000
+#define BRCFG_PCIE_RX1			0x00000004
+#define BRCFG_AXI_MASTER		0x00000008
+#define BRCFG_PCIE_TX			0x0000000C
+#define BRCFG_INTERRUPT			0x00000010
+#define BRCFG_RAM_DISABLE0		0x00000014
+#define BRCFG_RAM_DISABLE1		0x00000018
+#define BRCFG_PCIE_RELAXED_ORDER	0x0000001C
+#define BRCFG_PCIE_RX_MSG_FILTER	0x00000020
+
+/* Attribute registers */
+#define NWL_ATTRIB_100			0x00000190
+
+/* Egress - Bridge translation registers */
+#define E_BREG_CAPABILITIES		0x00000200
+#define E_BREG_STATUS			0x00000204
+#define E_BREG_CONTROL			0x00000208
+#define E_BREG_BASE_LO			0x00000210
+#define E_BREG_BASE_HI			0x00000214
+#define E_ECAM_CAPABILITIES		0x00000220
+#define E_ECAM_STATUS			0x00000224
+#define E_ECAM_CONTROL			0x00000228
+#define E_ECAM_BASE_LO			0x00000230
+#define E_ECAM_BASE_HI			0x00000234
+
+/* Ingress - address translations */
+#define I_MSII_CAPABILITIES		0x00000300
+#define I_MSII_CONTROL			0x00000308
+#define I_MSII_BASE_LO			0x00000310
+#define I_MSII_BASE_HI			0x00000314
+
+#define I_ISUB_CONTROL			0x000003E8
+#define SET_ISUB_CONTROL		BIT(0)
+/* Rxed msg fifo  - Interrupt status registers */
+#define MSGF_MISC_STATUS		0x00000400
+#define MSGF_MISC_MASK			0x00000404
+#define MSGF_LEG_STATUS			0x00000420
+#define MSGF_LEG_MASK			0x00000424
+#define MSGF_MSI_STATUS_LO		0x00000440
+#define MSGF_MSI_STATUS_HI		0x00000444
+#define MSGF_MSI_MASK_LO		0x00000448
+#define MSGF_MSI_MASK_HI		0x0000044C
+#define MSGF_RX_FIFO_POP		0x00000484
+#define MSGF_RX_FIFO_TYPE		0x00000488
+#define MSGF_RX_FIFO_ADDRLO		0x00000490
+#define MSGF_RX_FIFO_ADDRHI		0x00000494
+#define MSGF_RX_FIFO_DATA		0x00000498
+
+/* Msg filter mask bits */
+#define CFG_ENABLE_PM_MSG_FWD		BIT(1)
+#define CFG_ENABLE_INT_MSG_FWD		BIT(2)
+#define CFG_ENABLE_ERR_MSG_FWD		BIT(3)
+#define CFG_ENABLE_SLT_MSG_FWD		BIT(5)
+#define CFG_ENABLE_VEN_MSG_FWD		BIT(7)
+#define CFG_ENABLE_OTH_MSG_FWD		BIT(13)
+#define CFG_ENABLE_VEN_MSG_EN		BIT(14)
+#define CFG_ENABLE_VEN_MSG_VEN_INV	BIT(15)
+#define CFG_ENABLE_VEN_MSG_VEN_ID	GENMASK(31, 16)
+#define CFG_ENABLE_MSG_FILTER_MASK	(CFG_ENABLE_PM_MSG_FWD | \
+					CFG_ENABLE_INT_MSG_FWD | \
+					CFG_ENABLE_ERR_MSG_FWD | \
+					CFG_ENABLE_SLT_MSG_FWD | \
+					CFG_ENABLE_VEN_MSG_FWD | \
+					CFG_ENABLE_OTH_MSG_FWD | \
+					CFG_ENABLE_VEN_MSG_EN | \
+					CFG_ENABLE_VEN_MSG_VEN_INV | \
+					CFG_ENABLE_VEN_MSG_VEN_ID)
+
+/* Misc interrupt status mask bits */
+#define MSGF_MISC_SR_RXMSG_AVAIL	BIT(0)
+#define MSGF_MISC_SR_RXMSG_OVER		BIT(1)
+#define MSGF_MISC_SR_SLAVE_ERR		BIT(4)
+#define MSGF_MISC_SR_MASTER_ERR		BIT(5)
+#define MSGF_MISC_SR_I_ADDR_ERR		BIT(6)
+#define MSGF_MISC_SR_E_ADDR_ERR		BIT(7)
+
+#define MSGF_MISC_SR_PCIE_CORE		GENMASK(18, 16)
+#define MSGF_MISC_SR_PCIE_CORE_ERR	GENMASK(31, 20)
+
+#define MSGF_MISC_SR_MASKALL		(MSGF_MISC_SR_RXMSG_AVAIL | \
+					MSGF_MISC_SR_RXMSG_OVER | \
+					MSGF_MISC_SR_SLAVE_ERR | \
+					MSGF_MISC_SR_MASTER_ERR | \
+					MSGF_MISC_SR_I_ADDR_ERR | \
+					MSGF_MISC_SR_E_ADDR_ERR | \
+					MSGF_MISC_SR_PCIE_CORE | \
+					MSGF_MISC_SR_PCIE_CORE_ERR)
+
+/* Message rx fifo type mask bits */
+#define MSGF_RX_FIFO_TYPE_MSI	(1)
+#define MSGF_RX_FIFO_TYPE_TYPE	GENMASK(1, 0)
+
+/* Legacy interrupt status mask bits */
+#define MSGF_LEG_SR_INTA		BIT(0)
+#define MSGF_LEG_SR_INTB		BIT(1)
+#define MSGF_LEG_SR_INTC		BIT(2)
+#define MSGF_LEG_SR_INTD		BIT(3)
+#define MSGF_LEG_SR_MASKALL		(MSGF_LEG_SR_INTA | MSGF_LEG_SR_INTB | \
+					MSGF_LEG_SR_INTC | MSGF_LEG_SR_INTD)
+
+/* MSI interrupt status mask bits */
+#define MSGF_MSI_SR_LO_MASK		BIT(0)
+#define MSGF_MSI_SR_HI_MASK		BIT(0)
+
+#define MSII_PRESENT			BIT(0)
+#define MSII_ENABLE			BIT(0)
+#define MSII_STATUS_ENABLE		BIT(15)
+
+/* Bridge config interrupt mask */
+#define BRCFG_INTERRUPT_MASK		BIT(0)
+#define BREG_PRESENT			BIT(0)
+#define BREG_ENABLE			BIT(0)
+#define BREG_ENABLE_FORCE		BIT(1)
+
+/* E_ECAM status mask bits */
+#define E_ECAM_PRESENT			BIT(0)
+#define E_ECAM_SR_WR_PEND		BIT(16)
+#define E_ECAM_SR_RD_PEND		BIT(0)
+#define E_ECAM_SR_MASKALL		(E_ECAM_SR_WR_PEND | E_ECAM_SR_RD_PEND)
+#define E_ECAM_CR_ENABLE		BIT(0)
+#define E_ECAM_SIZE_LOC			GENMASK(20, 16)
+#define E_ECAM_SIZE_SHIFT		16
+#define ECAM_BUS_LOC_SHIFT		20
+#define ECAM_DEV_LOC_SHIFT		12
+#define NWL_ECAM_VALUE_DEFAULT		12
+#define NWL_ECAM_SIZE_MIN		4096
+
+#define ATTR_UPSTREAM_FACING		BIT(6)
+#define CFG_DMA_REG_BAR			GENMASK(2, 0)
+
+/* msgf_rx_fifo_pop bits */
+#define MSGF_RX_FIFO_POP_POP	BIT(0)
+
+#define INT_PCI_MSI_NR			(2 * 32)
+
+/* Readin the PS_LINKUP */
+#define PS_LINKUP_OFFSET			0x00000238
+#define PCIE_PHY_LINKUP_BIT			BIT(0)
+#define PHY_RDY_LINKUP_BIT			BIT(1)
+#define PCIE_USER_LINKUP			0
+#define PHY_RDY_LINKUP				1
+#define LINKUP_ITER_CHECK			5
+
+/* PCIE Message Request */
+#define TX_PCIE_MSG				0x00000620
+#define TX_PCIE_MSG_CNTL			0x00000004
+#define TX_PCIE_MSG_SPEC_LO			0x00000008
+#define TX_PCIE_MSG_SPEC_HI			0x0000000C
+#define TX_PCIE_MSG_DATA			0x00000010
+
+#define MSG_BUSY_BIT				BIT(8)
+#define MSG_EXECUTE_BIT				BIT(0)
+#define MSG_DONE_BIT				BIT(16)
+#define MSG_DONE_STATUS_BIT			(BIT(25) | BIT(24))
+#define RANDOM_DIGIT				0x11223344
+#define PATTRN_SSLP_TLP				0x01005074
+
+#define EXP_CAP_BASE				0x60
+
+/* SSPL ERROR */
+#define SLVERR					0x02
+#define DECERR					0x03
+
+struct nwl_msi {			/* struct nwl_msi - MSI information */
+	struct msi_controller msi_chip;	/* msi_chip: MSI domain */
+	DECLARE_BITMAP(used, INT_PCI_MSI_NR);	/* used: Declare Bitmap
+						for MSI	*/
+	struct irq_domain *dev_domain;	/* domain: MSI IRQ domain pointer */
+	unsigned long pages;		/* pages: MSI pages */
+	struct mutex lock;		/* lock: mutex lock */
+	int irq_msi0;			/* irq_msi0: msi0 interrupt number */
+	int irq_msi1;			/* irq_msi1: msi1 interrupt number */
+};
+
+/**
+ * struct nwl_pcie - PCIe port information
+ *
+ * @dev: Device pointer
+ * @breg_base: IO Mapped Bridge Register Base
+ * @pcireg_base: IO Mapped PCIe controller attributes
+ * @ecam_base: IO Mapped configuration space
+ * @phys_breg_base: Physical Bridge Register Base
+ * @phys_pcie_reg_base: Physical PCIe Controller Attributes
+ * @phys_ecam_base: Physical Configuration Base
+ * @breg_size: Bridge Register space
+ * @pcie_reg_size: PCIe controller attributes space
+ * @ecam_size: PCIe Configuration space
+ * @irq_intx: Legacy interrupt number
+ * @irq_misc: Misc interrupt number
+ * @ecam_value: ECAM value
+ * @last_busno: Last Bus number configured
+ * @link_up: Link status flag
+ * @bus: PCI bus
+ * @msi: MSI domain
+ * @legacy_irq_domain: legacy IRQ domain pointer
+ */
+struct nwl_pcie {
+	struct device *dev;
+	void __iomem *breg_base;
+	void __iomem *pcireg_base;
+	void __iomem *ecam_base;
+	u32 phys_breg_base;
+	u32 phys_pcie_reg_base;
+	u32 phys_ecam_base;
+	u32 breg_size;
+	u32 pcie_reg_size;
+	u32 ecam_size;
+	int irq_intx;
+	int irq_misc;
+	u32 ecam_value;
+	u8 last_busno;
+	u8 link_up;
+	struct pci_bus *bus;
+	struct nwl_msi msi;
+	struct irq_domain *legacy_irq_domain;
+};
+
+static inline u32 nwl_bridge_readl(struct nwl_pcie *pcie, u32 off)
+{
+	return readl(pcie->breg_base + off);
+}
+
+static inline void nwl_bridge_writel(struct nwl_pcie *pcie, u32 val, u32 off)
+{
+	writel(val, pcie->breg_base + off);
+}
+
+static inline bool nwl_pcie_link_up(struct nwl_pcie *pcie, u32 check_link_up)
+{
+	unsigned int status = -EINVAL;
+
+	if (check_link_up == PCIE_USER_LINKUP)
+		status = (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) &
+			  PCIE_PHY_LINKUP_BIT) ? 1 : 0;
+	else if (check_link_up == PHY_RDY_LINKUP)
+		status = (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) &
+			  PHY_RDY_LINKUP_BIT) ? 1 : 0;
+	return status;
+}
+
+/**
+ * nwl_pcie_get_config_base - Get configuration base
+ *
+ * @bus: Bus structure of current bus
+ * @devfn: Device/function
+ * @where: Offset from base
+ *
+ * Return: Base address of the configuration space needed to be
+ *	   accessed.
+ */
+static void __iomem *nwl_pcie_get_config_base(struct pci_bus *bus,
+						 unsigned int devfn,
+						 int where)
+{
+	struct nwl_pcie *pcie = bus->sysdata;
+	int relbus;
+
+	relbus = (bus->number << ECAM_BUS_LOC_SHIFT) |
+			(devfn << ECAM_DEV_LOC_SHIFT);
+
+	return pcie->ecam_base + relbus + where;
+}
+
+/**
+ * nwl_setup_sspl - Set Slot Power limit
+ *
+ * @pcie: PCIe port information
+ */
+static int nwl_setup_sspl(struct nwl_pcie *pcie)
+{
+	unsigned int status;
+	int retval = 0;
+
+	do {
+		status = nwl_bridge_readl(pcie, TX_PCIE_MSG) & MSG_BUSY_BIT;
+		if (!status) {
+			/*
+			 * Generate the TLP message for a single EP
+			 * [TODO] Add a multi-endpoint code
+			 */
+			nwl_bridge_writel(pcie, 0x0,
+					  TX_PCIE_MSG + TX_PCIE_MSG_CNTL);
+			nwl_bridge_writel(pcie, 0x0,
+					  TX_PCIE_MSG + TX_PCIE_MSG_SPEC_LO);
+			nwl_bridge_writel(pcie, 0x0,
+					  TX_PCIE_MSG + TX_PCIE_MSG_SPEC_HI);
+			nwl_bridge_writel(pcie, 0x0,
+					  TX_PCIE_MSG + TX_PCIE_MSG_DATA);
+			/* Pattern to generate SSLP TLP */
+			nwl_bridge_writel(pcie, PATTRN_SSLP_TLP,
+					  TX_PCIE_MSG + TX_PCIE_MSG_CNTL);
+			nwl_bridge_writel(pcie, RANDOM_DIGIT,
+					  TX_PCIE_MSG + TX_PCIE_MSG_DATA);
+			nwl_bridge_writel(pcie, nwl_bridge_readl(pcie,
+					  TX_PCIE_MSG) | 0x1, TX_PCIE_MSG);
+			status = 0;
+			mdelay(2);
+			status = nwl_bridge_readl(pcie, TX_PCIE_MSG)
+						  & MSG_DONE_BIT;
+			if (status) {
+				status = nwl_bridge_readl(pcie, TX_PCIE_MSG)
+						  & MSG_DONE_STATUS_BIT;
+				if (status == SLVERR) {
+					dev_err(pcie->dev, "AXI slave error");
+					retval = SLVERR;
+				} else if (status == DECERR) {
+					dev_err(pcie->dev, "AXI Decode error");
+					retval = DECERR;
+				}
+			} else {
+				retval = 1;
+			}
+		}
+	} while (status);
+
+	return retval;
+}
+
+/**
+ * nwl_nwl_readl_config - Read configuration space
+ *
+ * @bus: Bus structure of current bus
+ * @devfn: Device/function
+ * @where: Offset from base
+ * @size: Byte/word/dword
+ * @val: Value to be read
+ *
+ * Return: PCIBIOS_SUCCESSFUL on success
+ *	   PCIBIOS_DEVICE_NOT_FOUND on failure.
+ */
+static int nwl_nwl_readl_config(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				int size,
+				u32 *val)
+{
+	void __iomem *addr;
+
+	if (!bus->number && devfn > 0) {
+		*val = 0xFFFFFFFF;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	addr = nwl_pcie_get_config_base(bus, devfn, where);
+
+	switch (size) {
+	case 1:
+		*val = readb(addr);
+		break;
+	case 2:
+		*val = readw(addr);
+		break;
+	default:
+		*val = readl(addr);
+		break;
+	}
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/**
+ * nwl_nwl_writel_config - Write configuration space
+ *
+ * @bus: Bus structure of current bus
+ * @devfn: Device/function
+ * @where: Offset from base
+ * @size: Byte/word/dword
+ * @val: Value to be written to device
+ *
+ * Return: PCIBIOS_SUCCESSFUL on success,
+ *	   PCIBIOS_DEVICE_NOT_FOUND on failure.
+ */
+static int nwl_nwl_writel_config(struct pci_bus *bus,
+				unsigned int devfn,
+				int where,
+				int size,
+				u32 val)
+{
+	void __iomem *addr;
+	int retval;
+	struct nwl_pcie *pcie = bus->sysdata;
+
+	if (!bus->number && devfn > 0)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	addr = nwl_pcie_get_config_base(bus, devfn, where);
+
+	switch (size) {
+	case 1:
+		writeb(val, addr);
+		break;
+	case 2:
+		writew(val, addr);
+		break;
+	default:
+		writel(val, addr);
+		break;
+	}
+	if (addr == (pcie->ecam_base + EXP_CAP_BASE + PCI_EXP_SLTCAP)) {
+		retval = nwl_setup_sspl(pcie);
+		if (retval)
+			return PCIBIOS_SET_FAILED;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/* PCIe operations */
+static struct pci_ops nwl_pcie_ops = {
+	.read  = nwl_nwl_readl_config,
+	.write = nwl_nwl_writel_config,
+};
+
+static irqreturn_t nwl_pcie_misc_handler(int irq, void *data)
+{
+	struct nwl_pcie *pcie = (struct nwl_pcie *)data;
+	u32 misc_stat;
+
+	/* Checking for misc interrupts */
+	misc_stat = nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
+				     MSGF_MISC_SR_MASKALL;
+	if (!misc_stat)
+		return IRQ_NONE;
+
+	if (misc_stat & MSGF_MISC_SR_RXMSG_OVER)
+		dev_err(pcie->dev, "Received Message FIFO Overflow\n");
+
+	if (misc_stat & MSGF_MISC_SR_SLAVE_ERR)
+		dev_err(pcie->dev, "Slave error\n");
+
+	if (misc_stat & MSGF_MISC_SR_MASTER_ERR)
+		dev_err(pcie->dev, "Master error\n");
+
+	if (misc_stat & MSGF_MISC_SR_I_ADDR_ERR)
+		dev_err(pcie->dev,
+			"In Misc Ingress address translation error\n");
+
+	if (misc_stat & MSGF_MISC_SR_E_ADDR_ERR)
+		dev_err(pcie->dev,
+			"In Misc Egress address translation error\n");
+
+	if (misc_stat & MSGF_MISC_SR_PCIE_CORE_ERR)
+		dev_err(pcie->dev, "PCIe Core error\n");
+
+	/* Clear misc interrupt status */
+	nwl_bridge_writel(pcie, misc_stat, MSGF_MISC_STATUS);
+
+	return IRQ_HANDLED;
+}
+
+static void nwl_pcie_leg_handler(int irq, struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct nwl_pcie *pcie;
+	unsigned long status;
+	u32 bit;
+	u32 virq;
+
+	chained_irq_enter(chip, desc);
+	pcie = irq_desc_get_handler_data(desc);
+
+	while ((status = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
+				MSGF_LEG_SR_MASKALL) != 0) {
+		for_each_set_bit(bit, &status, 4) {
+
+			virq = irq_find_mapping(pcie->legacy_irq_domain,
+						bit + 1);
+			if (virq)
+				generic_handle_irq(virq);
+			else
+				dev_err(pcie->dev, "unexpected IRQ\n");
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+
+}
+
+static void nwl_pcie_msi_handler_high(unsigned int irq, struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct nwl_pcie *pcie;
+	struct nwl_msi *msi;
+	unsigned long status;
+	u32 bit;
+	u32 virq;
+
+	chained_irq_enter(chip, desc);
+	pcie = irq_desc_get_handler_data(desc);
+	msi = &pcie->msi;
+
+	while ((status = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_HI)) != 0) {
+		for_each_set_bit(bit, &status, 32) {
+			nwl_bridge_writel(pcie, 1 << bit, MSGF_MSI_STATUS_HI);
+			virq = irq_find_mapping(msi->dev_domain, bit);
+			if (virq)
+				generic_handle_irq(virq);
+			else
+				dev_err(pcie->dev, "unexpected MSI\n");
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+
+static void nwl_pcie_msi_handler_low(unsigned int irq, struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct nwl_pcie *pcie;
+	struct nwl_msi *msi;
+	unsigned long status;
+	u32 bit;
+	u32 virq;
+
+	chained_irq_enter(chip, desc);
+	pcie = irq_desc_get_handler_data(desc);
+	msi = &pcie->msi;
+
+	while ((status = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO)) != 0) {
+		for_each_set_bit(bit, &status, 32) {
+			nwl_bridge_writel(pcie, 1 << bit, MSGF_MSI_STATUS_LO);
+			virq = irq_find_mapping(msi->dev_domain, bit);
+			if (virq)
+				generic_handle_irq(virq);
+			else
+				dev_err(pcie->dev, "unexpected MSI\n");
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static int nwl_legacy_map(struct irq_domain *domain, unsigned int irq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
+	irq_set_chip_data(irq, domain->host_data);
+	set_irq_flags(irq, IRQF_VALID);
+
+	return 0;
+}
+
+static const struct irq_domain_ops legacy_domain_ops = {
+	.map = nwl_legacy_map,
+};
+
+#ifdef CONFIG_PCI_MSI
+static struct irq_chip nwl_msi_irq_chip = {
+	.name = "nwl_pcie:msi",
+	.irq_enable = unmask_msi_irq,
+	.irq_disable = mask_msi_irq,
+	.irq_mask = mask_msi_irq,
+	.irq_unmask = unmask_msi_irq,
+
+};
+
+static struct msi_domain_info nwl_msi_domain_info = {
+	.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
+	.chip = &nwl_msi_irq_chip,
+};
+#endif
+
+static void nwl_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
+	struct nwl_msi *msi = &pcie->msi;
+
+	msg->address_lo = virt_to_phys((void *)msi->pages);
+	msg->address_hi = 0;
+	msg->data = data->hwirq;
+
+}
+
+static int nwl_msi_set_affinity(struct irq_data *irq_data,
+				const struct cpumask *mask, bool force)
+{
+	return -EINVAL;
+}
+
+static struct irq_chip nwl_irq_chip = {
+	.name = "Xilinx MSI",
+	.irq_compose_msi_msg = nwl_compose_msi_msg,
+	.irq_set_affinity = nwl_msi_set_affinity,
+};
+
+static int nwl_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				unsigned int nr_irqs, void *args)
+{
+	struct nwl_pcie *pcie = domain->host_data;
+	struct nwl_msi *msi = &pcie->msi;
+	unsigned long bit;
+
+	mutex_lock(&msi->lock);
+	bit = find_first_zero_bit(msi->used, INT_PCI_MSI_NR);
+	if (bit < INT_PCI_MSI_NR)
+		set_bit(bit, msi->used);
+	else
+		bit = -ENOSPC;
+
+	mutex_unlock(&msi->lock);
+	irq_domain_set_info(domain, virq, bit, &nwl_irq_chip,
+			domain->host_data, handle_simple_irq,
+			NULL, NULL);
+	return 0;
+}
+
+static void nwl_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+					unsigned int nr_irqs)
+{
+	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
+	struct nwl_msi *msi = &pcie->msi;
+
+	if (!test_bit(data->hwirq, msi->used))
+		dev_err(pcie->dev, "freeing unused MSI %lu\n", data->hwirq);
+	else
+		clear_bit(data->hwirq, msi->used);
+
+}
+
+static const struct irq_domain_ops dev_msi_domain_ops = {
+	.alloc  = nwl_irq_domain_alloc,
+	.free   = nwl_irq_domain_free,
+};
+
+static void nwl_pcie_free_irq_domain(struct nwl_pcie *pcie)
+{
+	int i;
+	u32 irq;
+
+#ifdef CONFIG_PCI_MSI
+	struct nwl_msi *msi = &pcie->msi;
+#endif
+
+	for (i = 0; i < 4; i++) {
+		irq = irq_find_mapping(pcie->legacy_irq_domain, i + 1);
+		if (irq > 0)
+			irq_dispose_mapping(irq);
+	}
+
+	irq_domain_remove(pcie->legacy_irq_domain);
+
+#ifdef CONFIG_PCI_MSI
+	irq_set_chained_handler(msi->irq_msi0, NULL);
+	irq_set_handler_data(msi->irq_msi0, NULL);
+	irq_set_chained_handler(msi->irq_msi1, NULL);
+	irq_set_handler_data(msi->irq_msi1, NULL);
+
+	irq_domain_remove(msi->msi_chip.domain);
+	irq_domain_remove(msi->dev_domain);
+#endif
+
+}
+
+static int nwl_pcie_init_irq_domain(struct nwl_pcie *pcie)
+{
+	struct device_node *node = pcie->dev->of_node;
+	struct device_node *legacy_intc_node;
+
+#ifdef CONFIG_PCI_MSI
+	struct nwl_msi *msi = &pcie->msi;
+#endif
+
+	legacy_intc_node = of_get_next_child(node, NULL);
+	if (!legacy_intc_node) {
+		dev_err(pcie->dev, "No legacy intc node found\n");
+		return PTR_ERR(legacy_intc_node);
+	}
+
+	pcie->legacy_irq_domain = irq_domain_add_linear(legacy_intc_node, 4,
+							&legacy_domain_ops,
+							pcie);
+
+	if (!pcie->legacy_irq_domain) {
+		dev_err(pcie->dev, "failed to create IRQ domain\n");
+		return -ENOMEM;
+	}
+
+#ifdef CONFIG_PCI_MSI
+	msi->dev_domain = irq_domain_add_linear(NULL, INT_PCI_MSI_NR,
+					&dev_msi_domain_ops, pcie);
+	if (!msi->dev_domain) {
+		dev_err(pcie->dev, "failed to create dev IRQ domain\n");
+		return -ENOMEM;
+	}
+	msi->msi_chip.domain = pci_msi_create_irq_domain(node,
+							&nwl_msi_domain_info,
+							msi->dev_domain);
+	if (!msi->msi_chip.domain) {
+		dev_err(pcie->dev, "failed to create msi IRQ domain\n");
+		irq_domain_remove(msi->dev_domain);
+		return -ENOMEM;
+	}
+#endif
+	return 0;
+}
+
+static int nwl_pcie_enable_msi(struct nwl_pcie *pcie, struct pci_bus *bus)
+{
+	struct platform_device *pdev = to_platform_device(pcie->dev);
+	struct nwl_msi *msi = &pcie->msi;
+	unsigned long base;
+	int ret;
+
+	mutex_init(&msi->lock);
+
+	msi->msi_chip.dev = pcie->dev;
+	bus->msi = &msi->msi_chip;
+
+	/* Check for msii_present bit */
+	ret = nwl_bridge_readl(pcie, I_MSII_CAPABILITIES) & MSII_PRESENT;
+	if (!ret) {
+		dev_err(pcie->dev, "MSI not present\n");
+		ret = -EIO;
+		goto err;
+	}
+
+	/* Enable MSII */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
+			  MSII_ENABLE, I_MSII_CONTROL);
+
+	/* Enable MSII status */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
+			  MSII_STATUS_ENABLE, I_MSII_CONTROL);
+
+	/* setup AFI/FPCI range */
+	msi->pages = __get_free_pages(GFP_KERNEL, 0);
+	base = virt_to_phys((void *)msi->pages);
+	nwl_bridge_writel(pcie, base, I_MSII_BASE_LO);
+	nwl_bridge_writel(pcie, 0x0, I_MSII_BASE_HI);
+
+	/* Disable high range msi interrupts */
+	nwl_bridge_writel(pcie, (u32)~MSGF_MSI_SR_HI_MASK, MSGF_MSI_MASK_HI);
+
+	/* Clear pending high range msi interrupts */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie,  MSGF_MSI_STATUS_HI) &
+			  MSGF_MSI_SR_HI_MASK, MSGF_MSI_STATUS_HI);
+	/* Get msi_1 IRQ number */
+	msi->irq_msi1 = platform_get_irq_byname(pdev, "msi_1");
+	if (msi->irq_msi1 < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ#%d\n", msi->irq_msi1);
+		goto err;
+	}
+	/* Register msi handler */
+	irq_set_chained_handler_and_data(msi->irq_msi1,
+					 nwl_pcie_msi_handler_high, pcie);
+
+	/* Enable all high range msi interrupts */
+	nwl_bridge_writel(pcie, MSGF_MSI_SR_HI_MASK, MSGF_MSI_MASK_HI);
+
+	/* Disable low range msi interrupts */
+	nwl_bridge_writel(pcie, (u32)~MSGF_MSI_SR_LO_MASK, MSGF_MSI_MASK_LO);
+
+	/* Clear pending low range msi interrupts */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO) &
+			  MSGF_MSI_SR_LO_MASK, MSGF_MSI_STATUS_LO);
+	/* Get msi_0 IRQ number */
+	msi->irq_msi0 = platform_get_irq_byname(pdev, "msi_0");
+	if (msi->irq_msi0 < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ#%d\n", msi->irq_msi0);
+		goto err;
+	}
+	pr_info("MSI irq0 %x\n", msi->irq_msi0);
+
+	/* Register msi handler */
+	irq_set_chained_handler_and_data(msi->irq_msi0,
+					 nwl_pcie_msi_handler_low, pcie);
+
+	/* Enable all low range msi interrupts */
+	nwl_bridge_writel(pcie, MSGF_MSI_SR_LO_MASK, MSGF_MSI_MASK_LO);
+
+	return 0;
+err:
+	return ret;
+}
+
+static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
+{
+	struct platform_device *pdev = to_platform_device(pcie->dev);
+	u32 breg_val, ecam_val, first_busno = 0;
+	int err;
+	int check_link_up = 0;
+
+	/* Check for BREG present bit */
+	breg_val = nwl_bridge_readl(pcie, E_BREG_CAPABILITIES) & BREG_PRESENT;
+	if (!breg_val) {
+		dev_err(pcie->dev, "BREG is not present\n");
+		return breg_val;
+	}
+	/* Write bridge_off to breg base */
+	nwl_bridge_writel(pcie, (u32)(pcie->phys_breg_base),
+			  E_BREG_BASE_LO);
+
+	/* Enable BREG */
+	nwl_bridge_writel(pcie, ~BREG_ENABLE_FORCE & BREG_ENABLE,
+			  E_BREG_CONTROL);
+
+	/* Disable DMA channel registers */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_PCIE_RX0) |
+			  CFG_DMA_REG_BAR, BRCFG_PCIE_RX0);
+
+	/* Enable the bridge config interrupt */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_INTERRUPT) |
+			  BRCFG_INTERRUPT_MASK, BRCFG_INTERRUPT);
+	/* Enable Ingress subtractive decode translation */
+	nwl_bridge_writel(pcie, SET_ISUB_CONTROL, I_ISUB_CONTROL);
+
+	/* Enable msg filtering details */
+	nwl_bridge_writel(pcie, CFG_ENABLE_MSG_FILTER_MASK,
+			  BRCFG_PCIE_RX_MSG_FILTER);
+	do {
+		err = nwl_pcie_link_up(pcie, PHY_RDY_LINKUP);
+		if (err != 1) {
+			check_link_up++;
+			if (check_link_up > LINKUP_ITER_CHECK)
+				return -ENODEV;
+			mdelay(1000);
+		}
+	} while (!err);
+
+	/* Check for ECAM present bit */
+	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CAPABILITIES) & E_ECAM_PRESENT;
+	if (!ecam_val) {
+		dev_err(pcie->dev, "ECAM is not present\n");
+		return ecam_val;
+	}
+
+	/* Enable ECAM */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
+			  E_ECAM_CR_ENABLE, E_ECAM_CONTROL);
+	/* Write ecam_value on ecam_control */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
+			  (pcie->ecam_value << E_ECAM_SIZE_SHIFT),
+			  E_ECAM_CONTROL);
+	/* Write phy_reg_base to ecam base */
+	nwl_bridge_writel(pcie, (u32)pcie->phys_ecam_base, E_ECAM_BASE_LO);
+
+	/* Get bus range */
+	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CONTROL);
+	pcie->last_busno = (ecam_val & E_ECAM_SIZE_LOC) >> E_ECAM_SIZE_SHIFT;
+	/* Write primary, secondary and subordinate bus numbers */
+	ecam_val = first_busno;
+	ecam_val |= (first_busno + 1) << 8;
+	ecam_val |= (pcie->last_busno << E_ECAM_SIZE_SHIFT);
+	writel(ecam_val, (pcie->ecam_base + PCI_PRIMARY_BUS));
+
+	/* Check if PCIe link is up? */
+	pcie->link_up = nwl_pcie_link_up(pcie, PCIE_USER_LINKUP);
+	if (!pcie->link_up)
+		dev_info(pcie->dev, "Link is DOWN\n");
+	else
+		dev_info(pcie->dev, "Link is UP\n");
+
+	/* Disable all misc interrupts */
+	nwl_bridge_writel(pcie, (u32)~MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
+
+	/* Clear pending misc interrupts */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
+			  MSGF_MISC_SR_MASKALL, MSGF_MISC_STATUS);
+
+	/* Get misc IRQ number */
+	pcie->irq_misc = platform_get_irq_byname(pdev, "misc");
+	if (pcie->irq_misc < 0) {
+		dev_err(&pdev->dev, "failed to get misc IRQ#%d\n",
+			pcie->irq_misc);
+		return pcie->irq_misc;
+	}
+	/* Register misc handler */
+	err = devm_request_irq(pcie->dev, pcie->irq_misc,
+			       nwl_pcie_misc_handler, IRQF_SHARED,
+			       "nwl_pcie:misc", pcie);
+	if (err) {
+		dev_err(pcie->dev, "fail to register misc IRQ#%d\n",
+			pcie->irq_misc);
+		return err;
+	}
+	/* Enable all misc interrupts */
+	nwl_bridge_writel(pcie, MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
+
+	/* Disable all legacy interrupts */
+	nwl_bridge_writel(pcie, (u32)~MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
+
+	/* Clear pending legacy interrupts */
+	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
+			  MSGF_LEG_SR_MASKALL, MSGF_LEG_STATUS);
+	/* Get intx IRQ number */
+	pcie->irq_intx = platform_get_irq_byname(pdev, "intx");
+	if (pcie->irq_intx < 0) {
+		dev_err(&pdev->dev, "failed to get intx IRQ#%d\n",
+			pcie->irq_intx);
+		return pcie->irq_intx;
+	}
+
+	/* Enable all legacy interrupts */
+	nwl_bridge_writel(pcie, MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
+
+	return 0;
+}
+
+static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
+					struct platform_device *pdev)
+{
+	struct device_node *node = pcie->dev->of_node;
+	struct resource *res;
+	const char *type;
+
+	/* Check for device type */
+	type = of_get_property(node, "device_type", NULL);
+	if (!type || strcmp(type, "pci")) {
+		dev_err(pcie->dev, "invalid \"device_type\" %s\n", type);
+		return -EINVAL;
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "breg");
+	pcie->breg_base = devm_ioremap_resource(pcie->dev, res);
+	if (IS_ERR(pcie->breg_base))
+		return PTR_ERR(pcie->breg_base);
+	pcie->phys_breg_base = res->start;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcireg");
+	pcie->pcireg_base = devm_ioremap_resource(pcie->dev, res);
+	if (IS_ERR(pcie->pcireg_base))
+		return PTR_ERR(pcie->pcireg_base);
+	pcie->phys_pcie_reg_base = res->start;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+	pcie->ecam_base = devm_ioremap_resource(pcie->dev, res);
+	if (IS_ERR(pcie->ecam_base))
+		return PTR_ERR(pcie->ecam_base);
+	pcie->phys_ecam_base = res->start;
+
+	/* Get intx IRQ number */
+	pcie->irq_intx = platform_get_irq_byname(pdev, "intx");
+	if (pcie->irq_intx < 0) {
+		dev_err(&pdev->dev, "failed to get intx IRQ#%d\n",
+			pcie->irq_intx);
+		return pcie->irq_intx;
+	}
+
+	/* Register intx handler */
+	irq_set_chained_handler_and_data(pcie->irq_intx,
+					 nwl_pcie_leg_handler, pcie);
+
+	return 0;
+}
+
+static const struct of_device_id nwl_pcie_of_match[] = {
+	{ .compatible = "xlnx,nwl-pcie-2.11", },
+	{}
+};
+
+static int nwl_pcie_probe(struct platform_device *pdev)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct nwl_pcie *pcie;
+	struct pci_bus *bus;
+	int err;
+
+	resource_size_t iobase = 0;
+	LIST_HEAD(res);
+
+	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
+	if (!pcie)
+		return -ENOMEM;
+
+	pcie->ecam_value = NWL_ECAM_VALUE_DEFAULT;
+
+	pcie->dev = &pdev->dev;
+
+	err = nwl_pcie_parse_dt(pcie, pdev);
+	if (err) {
+		dev_err(pcie->dev, "Parsing DT failed\n");
+		return err;
+	}
+	/* Bridge initialization */
+	err = nwl_pcie_bridge_init(pcie);
+	if (err) {
+		dev_err(pcie->dev, "HW Initalization failed\n");
+		return err;
+	}
+
+	err = of_pci_get_host_bridge_resources(node, 0, 0xff, &res, &iobase);
+	if (err) {
+		pr_err("Getting bridge resources failed\n");
+		return err;
+	}
+
+	err = nwl_pcie_init_irq_domain(pcie);
+	if (err) {
+		dev_err(pcie->dev, "Failed creating IRQ Domain\n");
+		return err;
+	}
+
+	bus = pci_create_root_bus(&pdev->dev, 0,
+				  &nwl_pcie_ops, pcie, &res);
+	if (!bus)
+		return -ENOMEM;
+
+	/* Enable MSI */
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		err = nwl_pcie_enable_msi(pcie, bus);
+		if (err < 0) {
+			dev_err(&pdev->dev,
+				"failed to enable MSI support: %d\n", err);
+			return err;
+		}
+	}
+	pci_scan_child_bus(bus);
+	pci_assign_unassigned_bus_resources(bus);
+	pci_bus_add_devices(bus);
+	platform_set_drvdata(pdev, pcie);
+
+	return 0;
+}
+
+static int nwl_pcie_remove(struct platform_device *pdev)
+{
+	struct nwl_pcie *pcie = platform_get_drvdata(pdev);
+
+	nwl_pcie_free_irq_domain(pcie);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static struct platform_driver nwl_pcie_driver = {
+	.driver = {
+		.name = "nwl-pcie",
+		.of_match_table = nwl_pcie_of_match,
+	},
+	.probe = nwl_pcie_probe,
+	.remove = nwl_pcie_remove,
+};
+module_platform_driver(nwl_pcie_driver);
+
+MODULE_AUTHOR("Xilinx, Inc");
+MODULE_DESCRIPTION("NWL PCIe driver");
+MODULE_LICENSE("GPL");
--
1.7.1

Re: [PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[Arnd Bergmann]

On Saturday 17 October 2015 12:52:18 Bharat Kumar Gogada wrote:
> +       "msi_1, msi_0": interrupt asserted when msi is recieved

Better avoid underscores in DT, use "msi0" instead of "msi_0".

> +- interrupt-map-mask and 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
> +- msi-controller: indicates that this is MSI controller node
> +- msi-parent:  MSI parent of the root complex itself
> +- pcie_intc: Interrupt controller device node for Legacy interrupts
> +       - interrupt-controller: identifies the node as an interrupt controller
> +       - #interrupt-cells: should be set to 1
> +       - #address-cells: specifies the number of cells needed to encode an
> +               address. The value must be 0.

The name doesn't match: below, the name is "legacy-interrupt-controller",
not "pcie_intc". I suppose it should really be "interrupt-controller"
anyway.

> +
> +Example:
> +++++++++
> +
> +nwl_pcie: pcie@fd0e0000 {
> +       #address-cells = >;
> +       #size-cells = <2>;
> +       compatible = "xlnx,nwl-pcie-2.11";
> +       #interrupt-cells = <1>;
> +       msi-controller;
> +       device_type = "pci";
> +       interrupt-parent = <&gic>;
> +       interrupts = < 0 118 4
> +                      0 116 4
> +                      0 115 4          // MSI_1 [63...32]
> +                      0 114 4 >;       // MSI_0 [31...0]

Better write these as tuples:

	interrupts = <0 118 4>, <0 116 4>, <0 115 4>, <0 114 4>;

And maybe reverse the order? It looks that might be what the
soc integration person had in mind.

Also, what is interrupt <0 117 4>? Is that connected here as well?
Better list it as well then, even if you don't use it.

> +       interrupt-map-mask = <0x0 0x0 0x0 0x7>;
> +       interrupt-map = <0x0 0x0 0x0 0x1 &pcie_intc 0x1
> +                        0x0 0x0 0x0 0x2 &pcie_intc 0x2
> +                        0x0 0x0 0x0 0x3 &pcie_intc 0x3
> +                        0x0 0x0 0x0 0x4 &pcie_intc 0x4>;

> +       msi-parent = <&nwl_pcie>;
> +       reg = <0x0 0xfd0e0000 0x1000
> +              0x0 0xfd480000 0x1000
> +              0x0 0xE0000000 0x1000000>;

Same grouping for reg and interrupt-map as above for interrupts.

> +       reg-names = "breg", "pcireg", "cfg";
> +       ranges = <0x02000000 0x00000000 0xE1000000 0x00000000 0xE1000000 0 0x0F000000>;

No I/O space or prefetcheable memory?

	Arnd

Re: [PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[Josh Cartwright]

Hello,

I've got a few comments below.

On Sat, Oct 17, 2015 at 12:52:18PM +0530, Bharat Kumar Gogada wrote:
> Adding PCIe Root Port driver for Xilinx PCIe NWL bridge IP.
> 
> Signed-off-by: Bharat Kumar Gogada <bharatku@xilinx.com>
> Signed-off-by: Ravi Kiran Gummaluri <rgummal@xilinx.com>
> ---
> Added MSI domain implementation for handling MSI interrupts
> Added implementation for chained irq handlers
> Added legacy domain for handling legacy interrupts
> Added child node for handling legacy interrupt
[..]
> +++ b/drivers/pci/host/pcie-xilinx-nwl.c
[..]
> +static inline bool nwl_pcie_link_up(struct nwl_pcie *pcie, u32 check_link_up)
> +{
> +	unsigned int status = -EINVAL;
> +
> +	if (check_link_up == PCIE_USER_LINKUP)
> +		status = (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) &
> +			  PCIE_PHY_LINKUP_BIT) ? 1 : 0;
> +	else if (check_link_up == PHY_RDY_LINKUP)
> +		status = (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) &
> +			  PHY_RDY_LINKUP_BIT) ? 1 : 0;
> +	return status;

It would seem marginally simpler if the the bit to check was passed as
the argument, instead of a check_link_up -> bit mapping.

> +}
> +
> +/**
> + * nwl_pcie_get_config_base - Get configuration base
> + *
> + * @bus: Bus structure of current bus
> + * @devfn: Device/function
> + * @where: Offset from base
> + *
> + * Return: Base address of the configuration space needed to be
> + *	   accessed.
> + */
> +static void __iomem *nwl_pcie_get_config_base(struct pci_bus *bus,
> +						 unsigned int devfn,
> +						 int where)
> +{
> +	struct nwl_pcie *pcie = bus->sysdata;
> +	int relbus;
> +
> +	relbus = (bus->number << ECAM_BUS_LOC_SHIFT) |
> +			(devfn << ECAM_DEV_LOC_SHIFT);
> +
> +	return pcie->ecam_base + relbus + where;
> +}

It would seem you could simplify if you provide this as your map_bus
implementation of pci_ops.  Then you could use the
pci_generic_config_read/_write callbacks.

> +/**
> + * nwl_setup_sspl - Set Slot Power limit
> + *
> + * @pcie: PCIe port information
> + */
> +static int nwl_setup_sspl(struct nwl_pcie *pcie)
> +{
> +	unsigned int status;
> +	int retval = 0;
> +
> +	do {
> +		status = nwl_bridge_readl(pcie, TX_PCIE_MSG) & MSG_BUSY_BIT;
> +		if (!status) {
> +			/*
> +			 * Generate the TLP message for a single EP
> +			 * [TODO] Add a multi-endpoint code
> +			 */
> +			nwl_bridge_writel(pcie, 0x0,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_CNTL);
> +			nwl_bridge_writel(pcie, 0x0,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_SPEC_LO);
> +			nwl_bridge_writel(pcie, 0x0,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_SPEC_HI);
> +			nwl_bridge_writel(pcie, 0x0,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_DATA);
> +			/* Pattern to generate SSLP TLP */
> +			nwl_bridge_writel(pcie, PATTRN_SSLP_TLP,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_CNTL);
> +			nwl_bridge_writel(pcie, RANDOM_DIGIT,
> +					  TX_PCIE_MSG + TX_PCIE_MSG_DATA);
> +			nwl_bridge_writel(pcie, nwl_bridge_readl(pcie,
> +					  TX_PCIE_MSG) | 0x1, TX_PCIE_MSG);
> +			status = 0;

This assignment looks useless?

> +			mdelay(2);
> +			status = nwl_bridge_readl(pcie, TX_PCIE_MSG)
> +						  & MSG_DONE_BIT;
> +			if (status) {
> +				status = nwl_bridge_readl(pcie, TX_PCIE_MSG)
> +						  & MSG_DONE_STATUS_BIT;
> +				if (status == SLVERR) {
> +					dev_err(pcie->dev, "AXI slave error");
> +					retval = SLVERR;
> +				} else if (status == DECERR) {
> +					dev_err(pcie->dev, "AXI Decode error");
> +					retval = DECERR;
> +				}
> +			} else {
> +				retval = 1;
> +			}
> +		}
> +	} while (status);
> +
> +	return retval;
> +}
> +
[..]
> +static int nwl_nwl_writel_config(struct pci_bus *bus,
> +				unsigned int devfn,
> +				int where,
> +				int size,
> +				u32 val)
> +{
> +	void __iomem *addr;
> +	int retval;
> +	struct nwl_pcie *pcie = bus->sysdata;
> +
> +	if (!bus->number && devfn > 0)
> +		return PCIBIOS_DEVICE_NOT_FOUND;
> +
> +	addr = nwl_pcie_get_config_base(bus, devfn, where);
> +
> +	switch (size) {
> +	case 1:
> +		writeb(val, addr);
> +		break;
> +	case 2:
> +		writew(val, addr);
> +		break;
> +	default:
> +		writel(val, addr);
> +		break;
> +	}

Considering you can handle config space accesses smaller than a word,
the name of this function seems wrong :).

> +	if (addr == (pcie->ecam_base + EXP_CAP_BASE + PCI_EXP_SLTCAP)) {
> +		retval = nwl_setup_sspl(pcie);
> +		if (retval)
> +			return PCIBIOS_SET_FAILED;
> +	}

Ah, I see you need to do something special in this case.  Regardless,
you could still use pci_generic_config_write() from this function.

> +
> +	return PCIBIOS_SUCCESSFUL;
> +}
> +
> +/* PCIe operations */
> +static struct pci_ops nwl_pcie_ops = {

I wonder if there is a compelling reason why pci_ops hasn't been
constified yet.

> +	.read  = nwl_nwl_readl_config,
> +	.write = nwl_nwl_writel_config,
> +};
> +
> +static irqreturn_t nwl_pcie_misc_handler(int irq, void *data)
> +{
> +	struct nwl_pcie *pcie = (struct nwl_pcie *)data;

Nit: Don't need the cast.

> +	u32 misc_stat;
> +
[..]
> +static void nwl_pcie_leg_handler(int irq, struct irq_desc *desc)
> +{
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	struct nwl_pcie *pcie;
> +	unsigned long status;
> +	u32 bit;
> +	u32 virq;
> +
> +	chained_irq_enter(chip, desc);
> +	pcie = irq_desc_get_handler_data(desc);
> +
> +	while ((status = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
> +				MSGF_LEG_SR_MASKALL) != 0) {
> +		for_each_set_bit(bit, &status, 4) {
> +
> +			virq = irq_find_mapping(pcie->legacy_irq_domain,
> +						bit + 1);
> +			if (virq)
> +				generic_handle_irq(virq);
> +			else
> +				dev_err(pcie->dev, "unexpected IRQ\n");

The irq core will already handle this case for you, and better, as it
makes record of the spurious interrupt.

> +		}
> +	}
> +
> +	chained_irq_exit(chip, desc);
> +
> +}
> +
> +static void nwl_pcie_msi_handler_high(unsigned int irq, struct irq_desc *desc)
> +{
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	struct nwl_pcie *pcie;
> +	struct nwl_msi *msi;
> +	unsigned long status;
> +	u32 bit;
> +	u32 virq;
> +
> +	chained_irq_enter(chip, desc);
> +	pcie = irq_desc_get_handler_data(desc);
> +	msi = &pcie->msi;
> +
> +	while ((status = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_HI)) != 0) {
> +		for_each_set_bit(bit, &status, 32) {
> +			nwl_bridge_writel(pcie, 1 << bit, MSGF_MSI_STATUS_HI);
> +			virq = irq_find_mapping(msi->dev_domain, bit);
> +			if (virq)
> +				generic_handle_irq(virq);
> +			else
> +				dev_err(pcie->dev, "unexpected MSI\n");

Same here.

[..]
> +static void nwl_pcie_msi_handler_low(unsigned int irq, struct irq_desc *desc)
> +{
[..]
> +	while ((status = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO)) != 0) {
> +		for_each_set_bit(bit, &status, 32) {
> +			nwl_bridge_writel(pcie, 1 << bit, MSGF_MSI_STATUS_LO);
> +			virq = irq_find_mapping(msi->dev_domain, bit);
> +			if (virq)
> +				generic_handle_irq(virq);
> +			else
> +				dev_err(pcie->dev, "unexpected MSI\n");

And here.

> +		}
> +	}
> +
> +	chained_irq_exit(chip, desc);
> +}
> +
> +static int nwl_legacy_map(struct irq_domain *domain, unsigned int irq,
> +				irq_hw_number_t hwirq)
> +{
> +	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
> +	irq_set_chip_data(irq, domain->host_data);
> +	set_irq_flags(irq, IRQF_VALID);

There is an ongoing effort to kill more usages of the ARM-specific
set_irq_flags().  I don't actually think you need this at all, as the
IRQ domain takes care of the relevant pieces for you.

> +
> +	return 0;
> +}
> +
> +static const struct irq_domain_ops legacy_domain_ops = {
> +	.map = nwl_legacy_map,
> +};
> +
[..]
> +static int nwl_msi_set_affinity(struct irq_data *irq_data,
> +				const struct cpumask *mask, bool force)
> +{
> +	return -EINVAL;
> +}

This seems wrong.  Why even implement a irq_set_affinity() callback even
though you clearly cannot support it?

[..]
> +static void nwl_irq_domain_free(struct irq_domain *domain, unsigned int virq,
> +					unsigned int nr_irqs)
> +{
> +	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
> +	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
> +	struct nwl_msi *msi = &pcie->msi;
> +
> +	if (!test_bit(data->hwirq, msi->used))
> +		dev_err(pcie->dev, "freeing unused MSI %lu\n", data->hwirq);
> +	else
> +		clear_bit(data->hwirq, msi->used);

Is this racy, as you're not under &msi->lock?
> +
> +}
> +
[..]
> +static void nwl_pcie_free_irq_domain(struct nwl_pcie *pcie)
> +{
> +	int i;
> +	u32 irq;
> +
[..]
> +#ifdef CONFIG_PCI_MSI
> +	irq_set_chained_handler(msi->irq_msi0, NULL);
> +	irq_set_handler_data(msi->irq_msi0, NULL);

irq_set_chained_handler_and_data()?

> +	irq_set_chained_handler(msi->irq_msi1, NULL);
> +	irq_set_handler_data(msi->irq_msi1, NULL);
> +
> +	irq_domain_remove(msi->msi_chip.domain);
> +	irq_domain_remove(msi->dev_domain);
> +#endif
> +
> +}
> +
> +static int nwl_pcie_init_irq_domain(struct nwl_pcie *pcie)
> +{
> +	struct device_node *node = pcie->dev->of_node;
> +	struct device_node *legacy_intc_node;
> +
> +#ifdef CONFIG_PCI_MSI
> +	struct nwl_msi *msi = &pcie->msi;
> +#endif
> +
> +	legacy_intc_node = of_get_next_child(node, NULL);
> +	if (!legacy_intc_node) {
> +		dev_err(pcie->dev, "No legacy intc node found\n");
> +		return PTR_ERR(legacy_intc_node);

PTR_ERR() looks wrong here.

> +	}
> +
> +	pcie->legacy_irq_domain = irq_domain_add_linear(legacy_intc_node, 4,
> +							&legacy_domain_ops,
> +							pcie);
> +
> +	if (!pcie->legacy_irq_domain) {
> +		dev_err(pcie->dev, "failed to create IRQ domain\n");
> +		return -ENOMEM;
> +	}
> +
> +#ifdef CONFIG_PCI_MSI
> +	msi->dev_domain = irq_domain_add_linear(NULL, INT_PCI_MSI_NR,
> +					&dev_msi_domain_ops, pcie);
> +	if (!msi->dev_domain) {
> +		dev_err(pcie->dev, "failed to create dev IRQ domain\n");
> +		return -ENOMEM;
> +	}
> +	msi->msi_chip.domain = pci_msi_create_irq_domain(node,
> +							&nwl_msi_domain_info,
> +							msi->dev_domain);
> +	if (!msi->msi_chip.domain) {
> +		dev_err(pcie->dev, "failed to create msi IRQ domain\n");
> +		irq_domain_remove(msi->dev_domain);
> +		return -ENOMEM;
> +	}
> +#endif
> +	return 0;
> +}
> +
[..]
> +static const struct of_device_id nwl_pcie_of_match[] = {
> +	{ .compatible = "xlnx,nwl-pcie-2.11", },
> +	{}
> +};

You may want a MODULE_DEVICE_TABLE(of, niwl_pcie_of_match) here, too.
(Although, I guess it doesn't matter as you are not building modularly).

  Josh

RE: [PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[Bharat Kumar Gogada]

> > +       device_type = "pci";
> > +       interrupt-parent = <&gic>;
> > +       interrupts = < 0 118 4
> > +                      0 116 4
> > +                      0 115 4          // MSI_1 [63...32]
> > +                      0 114 4 >;       // MSI_0 [31...0]
> 
> Better write these as tuples:
> 
> 	interrupts = <0 118 4>, <0 116 4>, <0 115 4>, <0 114 4>;
> 
> And maybe reverse the order? It looks that might be what the soc
> integration person had in mind.
> 
> Also, what is interrupt <0 117 4>? Is that connected here as well?
> Better list it as well then, even if you don't use it.
> 
We have it but not using it, we will list it.

> > +       interrupt-map-mask = <0x0 0x0 0x0 0x7>;
> > +       interrupt-map = <0x0 0x0 0x0 0x1 &pcie_intc 0x1
> > +                        0x0 0x0 0x0 0x2 &pcie_intc 0x2
> > +                        0x0 0x0 0x0 0x3 &pcie_intc 0x3
> > +                        0x0 0x0 0x0 0x4 &pcie_intc 0x4>;
> 
> > +       msi-parent = <&nwl_pcie>;
> > +       reg = <0x0 0xfd0e0000 0x1000
> > +              0x0 0xfd480000 0x1000
> > +              0x0 0xE0000000 0x1000000>;
> 
> Same grouping for reg and interrupt-map as above for interrupts.

Grouping reg and interrupt-map as tuples will make lengthy line and reduces readability, is it compulsory ?
> 
> > +       reg-names = "breg", "pcireg", "cfg";
> > +       ranges = <0x02000000 0x00000000 0xE1000000 0x00000000
> > + 0xE1000000 0 0x0F000000>;
> 
> No I/O space or prefetcheable memory?
> 
> 	Arnd

Re: [PATCH v4] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

[Michal Simek]

On 10/26/2015 11:26 AM, Bharat Kumar Gogada wrote:
>>> +       device_type = "pci";
>>> +       interrupt-parent = <&gic>;
>>> +       interrupts = < 0 118 4
>>> +                      0 116 4
>>> +                      0 115 4          // MSI_1 [63...32]
>>> +                      0 114 4 >;       // MSI_0 [31...0]
>>
>> Better write these as tuples:
>>
>> 	interrupts = <0 118 4>, <0 116 4>, <0 115 4>, <0 114 4>;
>>
>> And maybe reverse the order? It looks that might be what the soc
>> integration person had in mind.
>>
>> Also, what is interrupt <0 117 4>? Is that connected here as well?
>> Better list it as well then, even if you don't use it.
>>
> We have it but not using it, we will list it.
> 
>>> +       interrupt-map-mask = <0x0 0x0 0x0 0x7>;
>>> +       interrupt-map = <0x0 0x0 0x0 0x1 &pcie_intc 0x1
>>> +                        0x0 0x0 0x0 0x2 &pcie_intc 0x2
>>> +                        0x0 0x0 0x0 0x3 &pcie_intc 0x3
>>> +                        0x0 0x0 0x0 0x4 &pcie_intc 0x4>;
>>
>>> +       msi-parent = <&nwl_pcie>;
>>> +       reg = <0x0 0xfd0e0000 0x1000
>>> +              0x0 0xfd480000 0x1000
>>> +              0x0 0xE0000000 0x1000000>;
>>
>> Same grouping for reg and interrupt-map as above for interrupts.
> 
> Grouping reg and interrupt-map as tuples will make lengthy line and reduces readability, is it compulsory ?


FYI: Just this.
      reg = <0x0 0xfd0e0000 0x1000>,
            <0x0 0xfd480000 0x1000>,
            <0x0 0xe0000000 0x1000000>;

Also please make sure that you are using the same case for addresses.
That 0xE0000000 case above.

Thanks,
Michal