PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver
authorSubrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
Wed, 30 May 2018 15:34:03 +0000 (10:34 -0500)
committerBjorn Helgaas <bhelgaas@google.com>
Mon, 4 Jun 2018 17:02:40 +0000 (12:02 -0500)
Add a driver for Mobiveil AXI PCIe Host Bridge Soft IP - GPEX 4.0,
a PCIe gen4 IP. This IP has upto 8 outbound and inbound windows
for the address translation.

Signed-off-by: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
[bhelgaas: fold in mobiveil_pcie_of_match[] NULL termination from Wei
Yongjun <weiyongjun1@huawei.com>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
drivers/pci/host/pcie-mobiveil.c [new file with mode: 0644]

diff --git a/drivers/pci/host/pcie-mobiveil.c b/drivers/pci/host/pcie-mobiveil.c
new file mode 100644 (file)
index 0000000..2fa3ad6
--- /dev/null
@@ -0,0 +1,669 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host controller driver for Mobiveil PCIe Host controller
+ *
+ * Copyright (c) 2018 Mobiveil Inc.
+ * Author: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* register offsets and bit positions */
+
+/*
+ * translation tables are grouped into windows, each window registers are
+ * grouped into blocks of 4 or 16 registers each
+ */
+#define PAB_REG_BLOCK_SIZE     16
+#define PAB_EXT_REG_BLOCK_SIZE 4
+
+#define PAB_REG_ADDR(offset, win) (offset + (win * PAB_REG_BLOCK_SIZE))
+#define PAB_EXT_REG_ADDR(offset, win) (offset + (win * PAB_EXT_REG_BLOCK_SIZE))
+
+#define LTSSM_STATUS           0x0404
+#define  LTSSM_STATUS_L0_MASK  0x3f
+#define  LTSSM_STATUS_L0       0x2d
+
+#define PAB_CTRL               0x0808
+#define  AMBA_PIO_ENABLE_SHIFT 0
+#define  PEX_PIO_ENABLE_SHIFT  1
+#define  PAGE_SEL_SHIFT        13
+#define  PAGE_SEL_MASK         0x3f
+#define  PAGE_LO_MASK          0x3ff
+#define  PAGE_SEL_EN           0xc00
+#define  PAGE_SEL_OFFSET_SHIFT 10
+
+#define PAB_AXI_PIO_CTRL       0x0840
+#define  APIO_EN_MASK          0xf
+
+#define PAB_PEX_PIO_CTRL       0x08c0
+#define  PIO_ENABLE_SHIFT      0
+
+#define PAB_INTP_AMBA_MISC_ENB         0x0b0c
+#define PAB_INTP_AMBA_MISC_STAT        0x0b1c
+#define  PAB_INTP_INTX_MASK            0x01e0
+
+#define PAB_AXI_AMAP_CTRL(win) PAB_REG_ADDR(0x0ba0, win)
+#define  WIN_ENABLE_SHIFT      0
+#define  WIN_TYPE_SHIFT        1
+
+#define PAB_EXT_AXI_AMAP_SIZE(win)     PAB_EXT_REG_ADDR(0xbaf0, win)
+
+#define PAB_AXI_AMAP_AXI_WIN(win)      PAB_REG_ADDR(0x0ba4, win)
+#define  AXI_WINDOW_ALIGN_MASK         3
+
+#define PAB_AXI_AMAP_PEX_WIN_L(win)    PAB_REG_ADDR(0x0ba8, win)
+#define  PAB_BUS_SHIFT         24
+#define  PAB_DEVICE_SHIFT      19
+#define  PAB_FUNCTION_SHIFT    16
+
+#define PAB_AXI_AMAP_PEX_WIN_H(win)    PAB_REG_ADDR(0x0bac, win)
+#define PAB_INTP_AXI_PIO_CLASS         0x474
+
+#define PAB_PEX_AMAP_CTRL(win) PAB_REG_ADDR(0x4ba0, win)
+#define  AMAP_CTRL_EN_SHIFT    0
+#define  AMAP_CTRL_TYPE_SHIFT  1
+
+#define PAB_EXT_PEX_AMAP_SIZEN(win)    PAB_EXT_REG_ADDR(0xbef0, win)
+#define PAB_PEX_AMAP_AXI_WIN(win)      PAB_REG_ADDR(0x4ba4, win)
+#define PAB_PEX_AMAP_PEX_WIN_L(win)    PAB_REG_ADDR(0x4ba8, win)
+#define PAB_PEX_AMAP_PEX_WIN_H(win)    PAB_REG_ADDR(0x4bac, win)
+
+/* starting offset of INTX bits in status register */
+#define PAB_INTX_START 5
+
+/* outbound and inbound window definitions */
+#define WIN_NUM_0              0
+#define WIN_NUM_1              1
+#define CFG_WINDOW_TYPE        0
+#define IO_WINDOW_TYPE         1
+#define MEM_WINDOW_TYPE        2
+#define IB_WIN_SIZE            (256 * 1024 * 1024 * 1024)
+#define MAX_PIO_WINDOWS        8
+
+/* Parameters for the waiting for link up routine */
+#define LINK_WAIT_MAX_RETRIES  10
+#define LINK_WAIT_MIN  90000
+#define LINK_WAIT_MAX  100000
+
+struct mobiveil_pcie {
+       struct platform_device *pdev;
+       struct list_head resources;
+       void __iomem *config_axi_slave_base;    /* endpoint config base */
+       void __iomem *csr_axi_slave_base;       /* root port config base */
+       void __iomem *pcie_reg_base;    /* Physical PCIe Controller Base */
+       struct irq_domain *intx_domain;
+       raw_spinlock_t intx_mask_lock;
+       int irq;
+       int apio_wins;
+       int ppio_wins;
+       int ob_wins_configured;         /* configured outbound windows */
+       int ib_wins_configured;         /* configured inbound windows */
+       struct resource *ob_io_res;
+       char root_bus_nr;
+};
+
+static inline void csr_writel(struct mobiveil_pcie *pcie, const u32 value,
+               const u32 reg)
+{
+       writel_relaxed(value, pcie->csr_axi_slave_base + reg);
+}
+
+static inline u32 csr_readl(struct mobiveil_pcie *pcie, const u32 reg)
+{
+       return readl_relaxed(pcie->csr_axi_slave_base + reg);
+}
+
+static bool mobiveil_pcie_link_up(struct mobiveil_pcie *pcie)
+{
+       return (csr_readl(pcie, LTSSM_STATUS) &
+               LTSSM_STATUS_L0_MASK) == LTSSM_STATUS_L0;
+}
+
+static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
+{
+       struct mobiveil_pcie *pcie = bus->sysdata;
+
+       /* Only one device down on each root port */
+       if ((bus->number == pcie->root_bus_nr) && (devfn > 0))
+               return false;
+
+       /*
+        * Do not read more than one device on the bus directly
+        * attached to RC
+        */
+       if ((bus->primary == pcie->root_bus_nr) && (devfn > 0))
+               return false;
+
+       return true;
+}
+
+/*
+ * mobiveil_pcie_map_bus - routine to get the configuration base of either
+ * root port or endpoint
+ */
+static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
+                                       unsigned int devfn, int where)
+{
+       struct mobiveil_pcie *pcie = bus->sysdata;
+
+       if (!mobiveil_pcie_valid_device(bus, devfn))
+               return NULL;
+
+       if (bus->number == pcie->root_bus_nr) {
+               /* RC config access */
+               return pcie->csr_axi_slave_base + where;
+       }
+
+       /*
+        * EP config access (in Config/APIO space)
+        * Program PEX Address base (31..16 bits) with appropriate value
+        * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
+        * Relies on pci_lock serialization
+        */
+       csr_writel(pcie, bus->number << PAB_BUS_SHIFT |
+                       PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
+                       PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT,
+                       PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
+       return pcie->config_axi_slave_base + where;
+}
+
+static struct pci_ops mobiveil_pcie_ops = {
+       .map_bus = mobiveil_pcie_map_bus,
+       .read = pci_generic_config_read,
+       .write = pci_generic_config_write,
+};
+
+static void mobiveil_pcie_isr(struct irq_desc *desc)
+{
+       struct irq_chip *chip = irq_desc_get_chip(desc);
+       struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
+       struct device *dev = &pcie->pdev->dev;
+       u32 intr_status;
+       unsigned long shifted_status;
+       u32 bit, virq, val, mask;
+
+       /*
+        * The core provides interrupt for INTx.
+        * So we'll read INTx status.
+        */
+
+       chained_irq_enter(chip, desc);
+
+       /* read INTx status */
+       val = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
+       mask = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+       intr_status = val & mask;
+
+       /* Handle INTx */
+       if (intr_status & PAB_INTP_INTX_MASK) {
+               shifted_status = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT) >>
+                       PAB_INTX_START;
+               do {
+                       for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
+                               virq = irq_find_mapping(pcie->intx_domain,
+                                               bit + 1);
+                               if (virq)
+                                       generic_handle_irq(virq);
+                               else
+                                       dev_err_ratelimited(dev,
+                                               "unexpected IRQ, INT%d\n", bit);
+
+                               /* clear interrupt */
+                               csr_writel(pcie,
+                                       shifted_status << PAB_INTX_START,
+                                       PAB_INTP_AMBA_MISC_STAT);
+                       }
+               } while ((shifted_status >> PAB_INTX_START) != 0);
+       }
+
+       /* Clear the interrupt status */
+       csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
+       chained_irq_exit(chip, desc);
+}
+
+static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
+{
+       struct device *dev = &pcie->pdev->dev;
+       struct platform_device *pdev = pcie->pdev;
+       struct device_node *node = dev->of_node;
+       struct resource *res;
+       const char *type;
+
+       type = of_get_property(node, "device_type", NULL);
+       if (!type || strcmp(type, "pci")) {
+               dev_err(dev, "invalid \"device_type\" %s\n", type);
+               return -EINVAL;
+       }
+
+       /* map config resource */
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+                       "config_axi_slave");
+       pcie->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
+       if (IS_ERR(pcie->config_axi_slave_base))
+               return PTR_ERR(pcie->config_axi_slave_base);
+       pcie->ob_io_res = res;
+
+       /* map csr resource */
+       res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+                       "csr_axi_slave");
+       pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
+       if (IS_ERR(pcie->csr_axi_slave_base))
+               return PTR_ERR(pcie->csr_axi_slave_base);
+       pcie->pcie_reg_base = res->start;
+
+       /* read the number of windows requested */
+       if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
+               pcie->apio_wins = MAX_PIO_WINDOWS;
+
+       if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
+               pcie->ppio_wins = MAX_PIO_WINDOWS;
+
+       pcie->irq = platform_get_irq(pdev, 0);
+       if (pcie->irq <= 0) {
+               dev_err(dev, "failed to map IRQ: %d\n", pcie->irq);
+               return -ENODEV;
+       }
+
+       irq_set_chained_handler_and_data(pcie->irq, mobiveil_pcie_isr, pcie);
+
+       return 0;
+}
+
+/*
+ * select_paged_register - routine to access paged register of root complex
+ *
+ * registers of RC are paged, for this scheme to work
+ * extracted higher 6 bits of the offset will be written to pg_sel
+ * field of PAB_CTRL register and rest of the lower 10 bits enabled with
+ * PAGE_SEL_EN are used as offset of the register.
+ */
+static void select_paged_register(struct mobiveil_pcie *pcie, u32 offset)
+{
+       int pab_ctrl_dw, pg_sel;
+
+       /* clear pg_sel field */
+       pab_ctrl_dw = csr_readl(pcie, PAB_CTRL);
+       pab_ctrl_dw = (pab_ctrl_dw & ~(PAGE_SEL_MASK << PAGE_SEL_SHIFT));
+
+       /* set pg_sel field */
+       pg_sel = (offset >> PAGE_SEL_OFFSET_SHIFT) & PAGE_SEL_MASK;
+       pab_ctrl_dw |= ((pg_sel << PAGE_SEL_SHIFT));
+       csr_writel(pcie, pab_ctrl_dw, PAB_CTRL);
+}
+
+static void write_paged_register(struct mobiveil_pcie *pcie,
+               u32 val, u32 offset)
+{
+       u32 off = (offset & PAGE_LO_MASK) | PAGE_SEL_EN;
+
+       select_paged_register(pcie, offset);
+       csr_writel(pcie, val, off);
+}
+
+static u32 read_paged_register(struct mobiveil_pcie *pcie, u32 offset)
+{
+       u32 off = (offset & PAGE_LO_MASK) | PAGE_SEL_EN;
+
+       select_paged_register(pcie, offset);
+       return csr_readl(pcie, off);
+}
+
+static void program_ib_windows(struct mobiveil_pcie *pcie, int win_num,
+               int pci_addr, u32 type, u64 size)
+{
+       int pio_ctrl_val;
+       int amap_ctrl_dw;
+       u64 size64 = ~(size - 1);
+
+       if ((pcie->ib_wins_configured + 1) > pcie->ppio_wins) {
+               dev_err(&pcie->pdev->dev,
+                       "ERROR: max inbound windows reached !\n");
+               return;
+       }
+
+       pio_ctrl_val = csr_readl(pcie, PAB_PEX_PIO_CTRL);
+       csr_writel(pcie,
+               pio_ctrl_val | (1 << PIO_ENABLE_SHIFT), PAB_PEX_PIO_CTRL);
+       amap_ctrl_dw = read_paged_register(pcie, PAB_PEX_AMAP_CTRL(win_num));
+       amap_ctrl_dw = (amap_ctrl_dw | (type << AMAP_CTRL_TYPE_SHIFT));
+       amap_ctrl_dw = (amap_ctrl_dw | (1 << AMAP_CTRL_EN_SHIFT));
+
+       write_paged_register(pcie, amap_ctrl_dw | lower_32_bits(size64),
+                               PAB_PEX_AMAP_CTRL(win_num));
+
+       write_paged_register(pcie, upper_32_bits(size64),
+                               PAB_EXT_PEX_AMAP_SIZEN(win_num));
+
+       write_paged_register(pcie, pci_addr, PAB_PEX_AMAP_AXI_WIN(win_num));
+       write_paged_register(pcie, pci_addr, PAB_PEX_AMAP_PEX_WIN_L(win_num));
+       write_paged_register(pcie, 0, PAB_PEX_AMAP_PEX_WIN_H(win_num));
+}
+
+/*
+ * routine to program the outbound windows
+ */
+static void program_ob_windows(struct mobiveil_pcie *pcie, int win_num,
+               u64 cpu_addr, u64 pci_addr, u32 config_io_bit, u64 size)
+{
+
+       u32 value, type;
+       u64 size64 = ~(size - 1);
+
+       if ((pcie->ob_wins_configured + 1) > pcie->apio_wins) {
+               dev_err(&pcie->pdev->dev,
+                       "ERROR: max outbound windows reached !\n");
+               return;
+       }
+
+       /*
+        * program Enable Bit to 1, Type Bit to (00) base 2, AXI Window Size Bit
+        * to 4 KB in PAB_AXI_AMAP_CTRL register
+        */
+       type = config_io_bit;
+       value = csr_readl(pcie, PAB_AXI_AMAP_CTRL(win_num));
+       csr_writel(pcie, 1 << WIN_ENABLE_SHIFT | type << WIN_TYPE_SHIFT |
+                       lower_32_bits(size64), PAB_AXI_AMAP_CTRL(win_num));
+
+       write_paged_register(pcie, upper_32_bits(size64),
+                               PAB_EXT_AXI_AMAP_SIZE(win_num));
+
+       /*
+        * program AXI window base with appropriate value in
+        * PAB_AXI_AMAP_AXI_WIN0 register
+        */
+       value = csr_readl(pcie, PAB_AXI_AMAP_AXI_WIN(win_num));
+       csr_writel(pcie, cpu_addr & (~AXI_WINDOW_ALIGN_MASK),
+                       PAB_AXI_AMAP_AXI_WIN(win_num));
+
+       value = csr_readl(pcie, PAB_AXI_AMAP_PEX_WIN_H(win_num));
+
+       csr_writel(pcie, lower_32_bits(pci_addr),
+                       PAB_AXI_AMAP_PEX_WIN_L(win_num));
+       csr_writel(pcie, upper_32_bits(pci_addr),
+                       PAB_AXI_AMAP_PEX_WIN_H(win_num));
+
+       pcie->ob_wins_configured++;
+}
+
+static int mobiveil_bringup_link(struct mobiveil_pcie *pcie)
+{
+       int retries;
+
+       /* check if the link is up or not */
+       for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
+               if (mobiveil_pcie_link_up(pcie))
+                       return 0;
+
+               usleep_range(LINK_WAIT_MIN, LINK_WAIT_MAX);
+       }
+       dev_err(&pcie->pdev->dev, "link never came up\n");
+       return -ETIMEDOUT;
+}
+
+static int mobiveil_host_init(struct mobiveil_pcie *pcie)
+{
+       u32 value, pab_ctrl, type = 0;
+       int err;
+       struct resource_entry *win, *tmp;
+
+       err = mobiveil_bringup_link(pcie);
+       if (err) {
+               dev_info(&pcie->pdev->dev, "link bring-up failed\n");
+               return err;
+       }
+
+       /*
+        * program Bus Master Enable Bit in Command Register in PAB Config
+        * Space
+        */
+       value = csr_readl(pcie, PCI_COMMAND);
+       csr_writel(pcie, value | PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
+               PCI_COMMAND_MASTER, PCI_COMMAND);
+
+       /*
+        * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
+        * register
+        */
+       pab_ctrl = csr_readl(pcie, PAB_CTRL);
+       csr_writel(pcie, pab_ctrl | (1 << AMBA_PIO_ENABLE_SHIFT) |
+               (1 << PEX_PIO_ENABLE_SHIFT), PAB_CTRL);
+
+       csr_writel(pcie, PAB_INTP_INTX_MASK, PAB_INTP_AMBA_MISC_ENB);
+
+       /*
+        * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
+        * PAB_AXI_PIO_CTRL Register
+        */
+       value = csr_readl(pcie, PAB_AXI_PIO_CTRL);
+       csr_writel(pcie, value | APIO_EN_MASK, PAB_AXI_PIO_CTRL);
+
+       /*
+        * we'll program one outbound window for config reads and
+        * another default inbound window for all the upstream traffic
+        * rest of the outbound windows will be configured according to
+        * the "ranges" field defined in device tree
+        */
+
+       /* config outbound translation window */
+       program_ob_windows(pcie, pcie->ob_wins_configured,
+                       pcie->ob_io_res->start, 0, CFG_WINDOW_TYPE,
+                       resource_size(pcie->ob_io_res));
+
+       /* memory inbound translation window */
+       program_ib_windows(pcie, WIN_NUM_1, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
+
+       /* Get the I/O and memory ranges from DT */
+       resource_list_for_each_entry_safe(win, tmp, &pcie->resources) {
+               type = 0;
+               if (resource_type(win->res) == IORESOURCE_MEM)
+                       type = MEM_WINDOW_TYPE;
+               if (resource_type(win->res) == IORESOURCE_IO)
+                       type = IO_WINDOW_TYPE;
+               if (type) {
+                       /* configure outbound translation window */
+                       program_ob_windows(pcie, pcie->ob_wins_configured,
+                               win->res->start, 0, type,
+                               resource_size(win->res));
+               }
+       }
+
+       return err;
+}
+
+static void mobiveil_mask_intx_irq(struct irq_data *data)
+{
+       struct irq_desc *desc = irq_to_desc(data->irq);
+       struct mobiveil_pcie *pcie;
+       unsigned long flags;
+       u32 mask, shifted_val;
+
+       pcie = irq_desc_get_chip_data(desc);
+       mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
+       raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
+       shifted_val = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+       csr_writel(pcie, (shifted_val & (~mask)), PAB_INTP_AMBA_MISC_ENB);
+       raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
+}
+
+static void mobiveil_unmask_intx_irq(struct irq_data *data)
+{
+       struct irq_desc *desc = irq_to_desc(data->irq);
+       struct mobiveil_pcie *pcie;
+       unsigned long flags;
+       u32 shifted_val, mask;
+
+       pcie = irq_desc_get_chip_data(desc);
+       mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
+       raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
+       shifted_val = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+       csr_writel(pcie, (shifted_val | mask), PAB_INTP_AMBA_MISC_ENB);
+       raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
+}
+
+static struct irq_chip intx_irq_chip = {
+       .name = "mobiveil_pcie:intx",
+       .irq_enable = mobiveil_unmask_intx_irq,
+       .irq_disable = mobiveil_mask_intx_irq,
+       .irq_mask = mobiveil_mask_intx_irq,
+       .irq_unmask = mobiveil_unmask_intx_irq,
+};
+
+/* routine to setup the INTx related data */
+static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+               irq_hw_number_t hwirq)
+{
+       irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_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 = mobiveil_pcie_intx_map,
+};
+
+static int mobiveil_pcie_init_irq_domain(struct mobiveil_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 a INTx IRQ domain\n");
+               return -ENODEV;
+       }
+
+       raw_spin_lock_init(&pcie->intx_mask_lock);
+
+       return 0;
+}
+
+static int mobiveil_pcie_probe(struct platform_device *pdev)
+{
+       struct mobiveil_pcie *pcie;
+       struct pci_bus *bus;
+       struct pci_bus *child;
+       struct pci_host_bridge *bridge;
+       struct device *dev = &pdev->dev;
+       struct device_node *node = dev->of_node;
+       resource_size_t iobase;
+       int ret;
+
+       /* allocate the PCIe port */
+       bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
+       if (!bridge)
+               return -ENODEV;
+
+       pcie = pci_host_bridge_priv(bridge);
+       if (!pcie)
+               return -ENOMEM;
+
+       pcie->pdev = pdev;
+
+       ret = mobiveil_pcie_parse_dt(pcie);
+       if (ret) {
+               dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
+               return ret;
+       }
+
+       INIT_LIST_HEAD(&pcie->resources);
+
+       /* parse the host bridge base addresses from the device tree file */
+       ret = of_pci_get_host_bridge_resources(node, 0, 0xff,
+                       &pcie->resources, &iobase);
+       if (ret) {
+               dev_err(dev, "Getting bridge resources failed\n");
+               return -ENOMEM;
+       }
+
+       /*
+        * configure all inbound and outbound windows and prepare the RC for
+        * config access
+        */
+       ret = mobiveil_host_init(pcie);
+       if (ret) {
+               dev_err(dev, "Failed to initialize host\n");
+               goto error;
+       }
+
+       /* fixup for PCIe class register */
+       csr_writel(pcie, 0x060402ab, PAB_INTP_AXI_PIO_CLASS);
+
+       /* initialize the IRQ domains */
+       ret = mobiveil_pcie_init_irq_domain(pcie);
+       if (ret) {
+               dev_err(dev, "Failed creating IRQ Domain\n");
+               goto error;
+       }
+
+       ret = devm_request_pci_bus_resources(dev, &pcie->resources);
+       if (ret)
+               goto error;
+
+       /* Initialize bridge */
+       list_splice_init(&pcie->resources, &bridge->windows);
+       bridge->dev.parent = dev;
+       bridge->sysdata = pcie;
+       bridge->busnr = pcie->root_bus_nr;
+       bridge->ops = &mobiveil_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)
+               goto error;
+
+       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;
+error:
+       pci_free_resource_list(&pcie->resources);
+       return ret;
+}
+
+static const struct of_device_id mobiveil_pcie_of_match[] = {
+       {.compatible = "mbvl,gpex40-pcie",},
+       {},
+};
+
+MODULE_DEVICE_TABLE(of, mobiveil_pcie_of_match);
+
+static struct platform_driver mobiveil_pcie_driver = {
+       .probe = mobiveil_pcie_probe,
+       .driver = {
+                       .name = "mobiveil-pcie",
+                       .of_match_table = mobiveil_pcie_of_match,
+                       .suppress_bind_attrs = true,
+               },
+};
+
+builtin_platform_driver(mobiveil_pcie_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Mobiveil PCIe host controller driver");
+MODULE_AUTHOR("Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>");