keystone PCIe controller is based on v3.65 version of the
designware h/w. Main differences are
        1. No ATU support
        2. Legacy and MSI irq functions are implemented in
           application register space
        3. MSI interrupts are multiplexed over 8 IRQ lines to the Host
           side.
All of the Application register space handing code are organized into
pci-keystone-dw.c and the functions are called from pci-keystone.c
to implement PCI controller driver. Also add necessary DT documentation
for the driver.

Signed-off-by: Murali Karicheri <m-kariche...@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilim...@ti.com>

CC: Russell King <li...@arm.linux.org.uk>
CC: Grant Likely <grant.lik...@linaro.org>
CC: Rob Herring <robh...@kernel.org>
CC: Mohit Kumar <mohit.ku...@st.com>
CC: Jingoo Han <jg1....@samsung.com>
CC: Bjorn Helgaas <bhelg...@google.com>
CC: Pratyush Anand <pratyush.an...@st.com>
CC: Richard Zhu <r65...@freescale.com>
CC: Kishon Vijay Abraham I <kis...@ti.com>
CC: Marek Vasut <ma...@denx.de>
CC: Arnd Bergmann <a...@arndb.de>
CC: Pawel Moll <pawel.m...@arm.com>
CC: Mark Rutland <mark.rutl...@arm.com>
CC: Ian Campbell <ijc+devicet...@hellion.org.uk>
CC: Kumar Gala <ga...@codeaurora.org>
CC: Randy Dunlap <rdun...@infradead.org>
CC: Grant Likely <grant.lik...@linaro.org>
---
 .../devicetree/bindings/pci/pci-keystone.txt       |   69 +++
 drivers/pci/host/Kconfig                           |    5 +
 drivers/pci/host/Makefile                          |    1 +
 drivers/pci/host/pci-keystone-dw.c                 |  519 ++++++++++++++++++++
 drivers/pci/host/pci-keystone.c                    |  383 +++++++++++++++
 drivers/pci/host/pci-keystone.h                    |   56 +++
 6 files changed, 1033 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/pci-keystone.txt
 create mode 100644 drivers/pci/host/pci-keystone-dw.c
 create mode 100644 drivers/pci/host/pci-keystone.c
 create mode 100644 drivers/pci/host/pci-keystone.h

diff --git a/Documentation/devicetree/bindings/pci/pci-keystone.txt 
b/Documentation/devicetree/bindings/pci/pci-keystone.txt
new file mode 100644
index 0000000..bb39601
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pci-keystone.txt
@@ -0,0 +1,69 @@
+TI Keystone PCIe interface
+
+Keystone PCI host Controller is based on Designware PCI h/w version 3.65.
+It shares common functions with PCIE Designware core driver and inherit
+common properties defined in
+Documentation/devicetree/bindings/pci/designware-pci.txt
+Compatibility string "dw,snps-pcie-v3.65" is used to identify the verison
+of the DW h/w used on Keystone.
+
+Please refer to Documentation/devicetree/bindings/pci/designware-pci.txt
+for the details of designware DT bindings. Additional properties are
+described here as well propeties that are not applicable.
+
+Required Properties:-
+
+compatibility: "ti,keystone-pcie"
+reg:   index 1 is the base address and length of DW application registers.
+       index 2 is the base address and length of PCI mode configuration
+       register.
+       index 3 is the base address and length of PCI device ID register.
+
+pcie_msi_intc : Interrupt controller device node for MSI irq chip
+       interrupt-cells: should be set to 1
+       interrupt-parent: Parent interrupt controller phandle
+       interrupts: GIC interrupt lines connected to PCI MSI interrupt lines
+
+ Example:
+       pcie_msi_intc: msi-interrupt-controller {
+                       interrupt-controller;
+                       #interrupt-cells = <1>;
+                       interrupt-parent = <&gic>;
+                       interrupts = <GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 31 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 32 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 33 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 34 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 35 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 36 IRQ_TYPE_EDGE_RISING>,
+                                       <GIC_SPI 37 IRQ_TYPE_EDGE_RISING>;
+       };
+
+pcie_intc: Interrupt controller device node for Legacy irq chip
+       interrupt-cells: should be set to 1
+       interrupt-parent: Parent interrupt controller phandle
+       interrupts: GIC interrupt lines connected to PCI Legacy interrupt lines
+
+ Example:
+       pcie_intc: legacy-interrupt-controller {
+               interrupt-controller;
+               #interrupt-cells = <1>;
+               interrupt-parent = <&gic>;
+               interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>,
+                       <GIC_SPI 27 IRQ_TYPE_EDGE_RISING>,
+                       <GIC_SPI 28 IRQ_TYPE_EDGE_RISING>,
+                       <GIC_SPI 29 IRQ_TYPE_EDGE_RISING>;
+       };
+
+Optional properties:-
+       phys: phandle to Generic Keystone SerDes phy for PCI
+       phy-names: name of the Generic Keystine SerDes phy for PCI
+         - If boot loader already does PCI link establishment, then phys and
+           phy-names shouldn't be present.
+       ti,enable-linktrain - Enable Link training.
+         - If boot loader already does PCI link establishment, then this
+           shouldn't be present.
+
+Designware DT Properties not applicable for Keystone PCI
+
+1. pcie_bus clock-names not used. Instead, a phandle to phys is used.
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 21df477..f8bc475 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -46,4 +46,9 @@ config PCI_HOST_GENERIC
          Say Y here if you want to support a simple generic PCI host
          controller, such as the one emulated by kvmtool.
 
+config PCI_KEYSTONE
+       bool "TI Keystone PCIe controller"
+       depends on ARCH_KEYSTONE
+       select PCIE_DW
+       select PCIEPORTBUS
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 611ba4b..d1b6ce1 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
 obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
 obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o
 obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
+obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
diff --git a/drivers/pci/host/pci-keystone-dw.c 
b/drivers/pci/host/pci-keystone-dw.c
new file mode 100644
index 0000000..00a5a52
--- /dev/null
+++ b/drivers/pci/host/pci-keystone-dw.c
@@ -0,0 +1,519 @@
+/*
+ * Designware application register space functions for Keystone PCI controller
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ *             http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-kariche...@ti.com>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#include "pcie-designware.h"
+#include "pci-keystone.h"
+
+/* Application register defines */
+#define LTSSM_EN_VAL                   1
+#define LTSSM_STATE_MASK               0x1f
+#define LTSSM_STATE_L0                 0x11
+#define DBI_CS2_EN_VAL                 0x20
+#define OB_XLAT_EN_VAL                 2
+
+/* Application registers */
+#define CMD_STATUS                     0x004
+#define CFG_SETUP                      0x008
+#define OB_SIZE                                0x030
+#define CFG_PCIM_WIN_SZ_IDX            3
+#define CFG_PCIM_WIN_CNT               32
+#define SPACE0_REMOTE_CFG_OFFSET       0x1000
+#define OB_OFFSET_INDEX(n)             (0x200 + (8 * n))
+#define OB_OFFSET_HI(n)                        (0x204 + (8 * n))
+
+/* IRQ register defines */
+#define IRQ_EOI                                0x050
+#define IRQ_STATUS                     0x184
+#define IRQ_ENABLE_SET                 0x188
+#define IRQ_ENABLE_CLR                 0x18c
+
+#define MSI_IRQ                                0x054
+#define MSI0_IRQ_STATUS                        0x104
+#define MSI0_IRQ_ENABLE_SET            0x108
+#define MSI0_IRQ_ENABLE_CLR            0x10c
+#define IRQ_STATUS                     0x184
+#define MSI_IRQ_OFFSET                 4
+
+/* Config space registers */
+#define DEBUG0                         0x728
+
+#define to_keystone_pcie(x)    container_of(x, struct keystone_pcie, pp)
+
+static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
+{
+       return sys->private_data;
+}
+
+static inline void update_reg_offset_bit_pos(u32 offset, u32 *reg_offset,
+                                       u32 *bit_pos)
+{
+       *reg_offset = offset % 8;
+       *bit_pos = offset >> 3;
+}
+
+u32 ks_dw_pcie_get_msi_data(struct pcie_port *pp)
+{
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+       return ks_pcie->app.start + MSI_IRQ;
+}
+
+void ks_dw_pcie_handle_msi_irq(struct keystone_pcie *ks_pcie , int offset)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       u32 pending, vector;
+       int src, virq;
+
+       pending = readl(ks_pcie->va_app_base + MSI0_IRQ_STATUS + (offset << 4));
+       /*
+        * MSI0, Status bit 0-3 shows vectors 0, 8, 16, 24, MSI1 status bit
+        * shows 1, 9, 17, 25 and so forth
+        */
+       for (src = 0; src < 4; src++) {
+               if (BIT(src) & pending) {
+                       vector = offset + (src << 3);
+                       virq = irq_linear_revmap(pp->irq_domain, vector);
+                       dev_dbg(pp->dev,
+                               "irq: bit %d, vector %d, virq %d\n",
+                                src, vector, virq);
+                       generic_handle_irq(virq);
+               }
+       }
+}
+
+static void ks_dw_pcie_msi_irq_ack(struct irq_data *d)
+{
+       u32 offset, reg_offset, bit_pos;
+       struct keystone_pcie *ks_pcie;
+       unsigned int irq = d->irq;
+       struct msi_desc *msi;
+       struct pcie_port *pp;
+
+       msi = irq_get_msi_desc(irq);
+       pp = sys_to_pcie(msi->dev->bus->sysdata);
+       ks_pcie = to_keystone_pcie(pp);
+       offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+       update_reg_offset_bit_pos(offset, &reg_offset, &bit_pos);
+
+       writel(BIT(bit_pos),
+               ks_pcie->va_app_base + MSI0_IRQ_STATUS + (reg_offset << 4));
+       writel(reg_offset + MSI_IRQ_OFFSET, ks_pcie->va_app_base + IRQ_EOI);
+}
+
+void ks_dw_pcie_msi_set_irq(struct pcie_port *pp, int irq)
+{
+       u32 reg_offset, bit_pos;
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+       update_reg_offset_bit_pos(irq, &reg_offset, &bit_pos);
+       writel(BIT(bit_pos),
+               ks_pcie->va_app_base + MSI0_IRQ_ENABLE_SET + (reg_offset << 4));
+}
+
+void ks_dw_pcie_msi_clear_irq(struct pcie_port *pp, int irq)
+{
+       u32 reg_offset, bit_pos;
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+       update_reg_offset_bit_pos(irq, &reg_offset, &bit_pos);
+       writel(BIT(bit_pos),
+               ks_pcie->va_app_base + MSI0_IRQ_ENABLE_CLR + (reg_offset << 4));
+}
+
+static void ks_dw_pcie_msi_irq_mask(struct irq_data *d)
+{
+       struct keystone_pcie *ks_pcie;
+       unsigned int irq = d->irq;
+       struct msi_desc *msi;
+       struct pcie_port *pp;
+       u32 offset;
+
+       msi = irq_get_msi_desc(irq);
+       pp = sys_to_pcie(msi->dev->bus->sysdata);
+       ks_pcie = to_keystone_pcie(pp);
+       offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+
+       /* mask the end point if PVM implemented */
+       if (IS_ENABLED(CONFIG_PCI_MSI)) {
+               if (msi->msi_attrib.maskbit)
+                       mask_msi_irq(d);
+       }
+
+       ks_dw_pcie_msi_clear_irq(pp, offset);
+}
+
+static void ks_dw_pcie_msi_irq_unmask(struct irq_data *d)
+{
+       struct keystone_pcie *ks_pcie;
+       unsigned int irq = d->irq;
+       struct msi_desc *msi;
+       struct pcie_port *pp;
+       u32 offset;
+
+       msi = irq_get_msi_desc(irq);
+       pp = sys_to_pcie(msi->dev->bus->sysdata);
+       ks_pcie = to_keystone_pcie(pp);
+       offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+
+       /* mask the end point if PVM implemented */
+       if (IS_ENABLED(CONFIG_PCI_MSI)) {
+               if (msi->msi_attrib.maskbit)
+                       unmask_msi_irq(d);
+       }
+
+       ks_dw_pcie_msi_set_irq(pp, offset);
+}
+
+static struct irq_chip ks_dw_pcie_msi_irq_chip = {
+       .name = "Keystone-PCIe-MSI-IRQ",
+       .irq_ack = ks_dw_pcie_msi_irq_ack,
+       .irq_mask = ks_dw_pcie_msi_irq_mask,
+       .irq_unmask = ks_dw_pcie_msi_irq_unmask,
+};
+
+static int ks_dw_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
+                       irq_hw_number_t hwirq)
+{
+       irq_set_chip_and_handler(irq, &ks_dw_pcie_msi_irq_chip,
+                                handle_level_irq);
+       irq_set_chip_data(irq, domain->host_data);
+       set_irq_flags(irq, IRQF_VALID);
+
+       return 0;
+}
+
+const struct irq_domain_ops ks_dw_pcie_msi_domain_ops = {
+       .map = ks_dw_pcie_msi_map,
+};
+
+void ks_dw_pcie_enable_legacy_irqs(struct keystone_pcie *ks_pcie)
+{
+       int i;
+
+       for (i = 0; i < MAX_LEGACY_IRQS; i++)
+               writel(0x1, ks_pcie->va_app_base + IRQ_ENABLE_SET + (i << 4));
+}
+
+void ks_dw_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie, int offset)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       u32 pending;
+       int virq;
+
+       pending = readl(ks_pcie->va_app_base + IRQ_STATUS + (offset << 4));
+
+       if (BIT(0) & pending) {
+               virq = irq_linear_revmap(ks_pcie->legacy_irq_domain, offset);
+               dev_dbg(pp->dev,
+                       ": irq: irq_offset %d, virq %d\n", offset, virq);
+               generic_handle_irq(virq);
+       }
+
+       /* EOI the INTx interrupt */
+       writel(offset, ks_pcie->va_app_base + IRQ_EOI);
+}
+
+static void ks_dw_pcie_ack_legacy_irq(struct irq_data *d)
+{
+}
+
+static void ks_dw_pcie_mask_legacy_irq(struct irq_data *d)
+{
+}
+
+static void ks_dw_pcie_unmask_legacy_irq(struct irq_data *d)
+{
+}
+
+static struct irq_chip ks_dw_pcie_legacy_irq_chip = {
+       .name = "Keystone-PCI-Legacy-IRQ",
+       .irq_ack = ks_dw_pcie_ack_legacy_irq,
+       .irq_mask = ks_dw_pcie_mask_legacy_irq,
+       .irq_unmask = ks_dw_pcie_unmask_legacy_irq,
+};
+
+static int ks_dw_pcie_init_legacy_irq_map(struct irq_domain *d,
+                               unsigned int irq, irq_hw_number_t hw_irq)
+{
+       irq_set_chip_and_handler(irq, &ks_dw_pcie_legacy_irq_chip,
+                               handle_level_irq);
+       irq_set_chip_data(irq, d->host_data);
+       set_irq_flags(irq, IRQF_VALID);
+
+       return 0;
+}
+
+static const struct irq_domain_ops ks_dw_pcie_legacy_irq_domian_ops = {
+       .map = ks_dw_pcie_init_legacy_irq_map,
+       .xlate = irq_domain_xlate_onetwocell,
+};
+
+/**
+ * ks_dw_pcie_set_dbi_mode() - Set DBI mode to access overlaid BAR mask 
registers
+ *
+ * Since modification of dbi_cs2 involves different clock domain, read the
+ * status back to ensure the transition is complete.
+ */
+static void ks_dw_pcie_set_dbi_mode(void __iomem *reg_virt)
+{
+       u32 val;
+
+       writel(DBI_CS2_EN_VAL | readl(reg_virt + CMD_STATUS),
+                    reg_virt + CMD_STATUS);
+
+       do {
+               val = readl(reg_virt + CMD_STATUS);
+       } while (!(val & DBI_CS2_EN_VAL));
+}
+
+/**
+ * ks_dw_pcie_clear_dbi_mode() - Disable DBI mode
+ *
+ * Since modification of dbi_cs2 involves different clock domain, read the
+ * status back to ensure the transition is complete.
+ */
+static void ks_dw_pcie_clear_dbi_mode(void __iomem *reg_virt)
+{
+       u32 val;
+
+       writel(~DBI_CS2_EN_VAL & readl(reg_virt + CMD_STATUS),
+                    reg_virt + CMD_STATUS);
+
+       do {
+               val = readl(reg_virt + CMD_STATUS);
+       } while (val & DBI_CS2_EN_VAL);
+}
+
+void ks_dw_pcie_setup_rc_app_regs(struct keystone_pcie *ks_pcie)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       u32 start = pp->mem.start, end = pp->mem.end;
+       int i, tr_size;
+
+       /* disable BARS for inbound access */
+       ks_dw_pcie_set_dbi_mode(ks_pcie->va_app_base);
+       writel(0, pp->dbi_base + PCI_BASE_ADDRESS_0);
+       writel(0, pp->dbi_base + PCI_BASE_ADDRESS_1);
+       ks_dw_pcie_clear_dbi_mode(ks_pcie->va_app_base);
+
+       /* Set outbound translation size per window division */
+       writel(CFG_PCIM_WIN_SZ_IDX & 0x7, ks_pcie->va_app_base + OB_SIZE);
+
+       tr_size = (1 << (CFG_PCIM_WIN_SZ_IDX & 0x7)) * SZ_1M;
+
+       /* Using Direct 1:1 mapping of RC <-> PCI memory space */
+       for (i = 0; (i < CFG_PCIM_WIN_CNT) && (start < end); i++) {
+               writel(start | 1, ks_pcie->va_app_base + OB_OFFSET_INDEX(i));
+               writel(0, ks_pcie->va_app_base + OB_OFFSET_HI(i));
+               start += tr_size;
+       }
+
+       /* Enable OB translation */
+       writel(OB_XLAT_EN_VAL | readl(ks_pcie->va_app_base + CMD_STATUS),
+               ks_pcie->va_app_base + CMD_STATUS);
+}
+
+/**
+ * ks_pcie_cfg_addr() - Set up configuration space address for a
+ * device
+ *
+ * @ks_pcie: ptr to keystone_pcie structure
+ * @bus: Bus number the device is residing on
+ * @devfn: device, function number info
+ *
+ * Forms and returns the address of configuration space mapped in PCIESS
+ * address space 0. Also configures CFG_SETUP for remote configuration space
+ * access.
+ *
+ * The address space has two regions to access configuration - local and 
remote.
+ * We access local region for bus 0 (as RC is attached on bus 0) and remote
+ * region for others with TYPE 1 access when bus > 1. As for device on bus = 1,
+ * we will do TYPE 0 access as it will be on our secondary bus (logical).
+ * CFG_SETUP is needed only for remote configuration access.
+ */
+static void __iomem *ks_pcie_cfg_addr(struct keystone_pcie *ks_pcie, u8 bus,
+                                       unsigned int devfn)
+{
+       u8 device = PCI_SLOT(devfn), function = PCI_FUNC(devfn);
+       struct pcie_port *pp = &ks_pcie->pp;
+       u32 regval;
+
+       if (bus == 0)
+               return pp->dbi_base;
+
+       regval = (bus << 16) | (device << 8) | function;
+       /*
+        * Since Bus#1 will be a virtual bus, we need to have TYPE0
+        * access only.
+        * TYPE 1
+        */
+       if (bus != 1)
+               regval |= BIT(24);
+
+       writel(regval, ks_pcie->va_app_base + CFG_SETUP);
+
+       return pp->dbi_base + SPACE0_REMOTE_CFG_OFFSET;
+}
+
+int ks_dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+               unsigned int devfn, int where, int size, u32 *val)
+{
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+       u8 bus_num = bus->number;
+       void __iomem *addr;
+       int ret;
+
+       addr = ks_pcie_cfg_addr(ks_pcie, bus_num, devfn);
+       ret = dw_pcie_cfg_read(addr + (where & ~0x3), where, size, val);
+
+       return ret;
+}
+
+int ks_dw_pcie_wr_other_conf(struct pcie_port *pp,
+               struct pci_bus *bus, unsigned int devfn, int where,
+               int size, u32 val)
+{
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+       u8 bus_num = bus->number;
+       void __iomem *addr;
+
+       addr = ks_pcie_cfg_addr(ks_pcie, bus_num, devfn);
+       return dw_pcie_cfg_write(addr + (where & ~0x3), where, size, val);
+}
+
+/**
+ * ks_dw_pcie_set_ib_access() - Setup inbound access
+ *
+ * Configure BAR0 for inbound access. BAR0 is set up in h/w to have
+ * access to PCIESS application register space and just needs to set up
+ * inbound address (mainly used for MSI).
+ */
+static void ks_dw_pcie_set_ib_access(struct keystone_pcie *ks_pcie)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+
+       /* Configure and set up BAR0 */
+       ks_dw_pcie_set_dbi_mode(ks_pcie->va_app_base);
+
+       /* Enable BAR0 */
+       writel(1, pp->dbi_base + PCI_BASE_ADDRESS_0);
+       writel(SZ_4K - 1, pp->dbi_base + PCI_BASE_ADDRESS_0);
+
+       ks_dw_pcie_clear_dbi_mode(ks_pcie->va_app_base);
+
+        /*
+         * For BAR0, just setting bus address for inbound writes (MSI) should
+         * be sufficient. Use physical address to avoid any conflicts.
+         */
+       writel(ks_pcie->app.start, pp->dbi_base + PCI_BASE_ADDRESS_0);
+}
+
+/**
+ * ks_dw_pcie_v3_65_scan_bus() - common function to scan bus
+ *
+ * common function to scan v3_65 dw based pci bus. This also sets inbound 
access
+ * after scan.
+ */
+static struct pci_bus *ks_dw_pcie_v3_65_scan_bus(int nr,
+                                                struct pci_sys_data *sys)
+{
+       struct pcie_port *pp = sys_to_pcie(sys);
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+       struct pci_bus *bus;
+
+       bus = dw_pcie_scan_bus(nr, sys);
+       if (bus)
+               ks_dw_pcie_set_ib_access(ks_pcie);
+
+       return bus;
+}
+
+/**
+ * ks_dw_pcie_link_up() - Check if link up
+ *
+ */
+int ks_dw_pcie_link_up(struct pcie_port *pp)
+{
+       u32 val = readl(pp->dbi_base + DEBUG0);
+
+       return (val & LTSSM_STATE_MASK) == LTSSM_STATE_L0;
+}
+
+void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
+{
+       u32 val;
+
+       /* Initiate Link Training.  */
+       val = readl(ks_pcie->va_app_base + CMD_STATUS);
+       writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);
+}
+
+static struct hw_pci ks_dw_pcie_v3_65_hw = {
+       .nr_controllers = 1,
+       .setup          = dw_pcie_setup,
+       .scan           = ks_dw_pcie_v3_65_scan_bus,
+       .add_bus        = dw_pcie_add_bus,
+       .map_irq        = dw_pcie_map_irq,
+};
+
+/**
+ * ks_dw_pcie_host_init() - initialize host for v3_65 dw hardware
+ *
+ * It ioremap the register resources, initialize legacy irq domain
+ * and then call dw_pcie_v3_65_host_init() API to intialize the Keystone
+ * PCI host controller.
+ *
+ */
+int __init ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
+                               struct device_node *msi_intc_np)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       struct platform_device *pdev = to_platform_device(pp->dev);
+       struct resource *res;
+
+       /* index 0 is the config reg. space address */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       pp->dbi_base = devm_ioremap_resource(pp->dev, res);
+       if (IS_ERR(pp->dbi_base))
+               return PTR_ERR(pp->dbi_base);
+
+       /* index 1 is the application reg. space address */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+       ks_pcie->app = *res;
+       ks_pcie->va_app_base = devm_ioremap_resource(pp->dev, res);
+       if (IS_ERR(ks_pcie->va_app_base))
+               return PTR_ERR(ks_pcie->va_app_base);
+
+       /* create legacy irq domain */
+       ks_pcie->legacy_irq_domain =
+                       irq_domain_add_linear(ks_pcie->legacy_intc_np,
+                                       MAX_LEGACY_IRQS,
+                                       &ks_dw_pcie_legacy_irq_domian_ops,
+                                       NULL);
+       if (!ks_pcie->legacy_irq_domain) {
+               dev_err(pp->dev, "Failed to add irq domain for legacy irqs\n");
+               return -EINVAL;
+       }
+
+       return dw_pcie_v3_65_host_init(pp, &ks_dw_pcie_v3_65_hw, msi_intc_np,
+                                       &ks_dw_pcie_msi_domain_ops);
+}
diff --git a/drivers/pci/host/pci-keystone.c b/drivers/pci/host/pci-keystone.c
new file mode 100644
index 0000000..97845f7
--- /dev/null
+++ b/drivers/pci/host/pci-keystone.c
@@ -0,0 +1,383 @@
+/*
+ * PCIe host controller driver for Texas Instruments Keystone SoCs
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ *             http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-kariche...@ti.com>
+ * Implementation based on pci-exynos.c and pcie-designware.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/irqchip/chained_irq.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+
+#include "pcie-designware.h"
+#include "pci-keystone.h"
+
+#define DRIVER_NAME    "keystone-pcie"
+
+/* driver specific constants */
+#define MAX_MSI_HOST_IRQS              8
+#define MAX_LEGACY_HOST_IRQS           4
+
+/* RC mode settings masks */
+#define PCIE_RC_MODE           BIT(2)
+#define PCIE_MODE_MASK         (BIT(1) | BIT(2))
+
+/* DEV_STAT_CTRL */
+#define PCIE_CAP_BASE          0x70
+
+#define to_keystone_pcie(x)    container_of(x, struct keystone_pcie, pp)
+
+static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       int count = 200;
+
+       dw_pcie_setup_rc(pp);
+       if (ks_pcie->link_train)
+               ks_dw_pcie_initiate_link_train(ks_pcie);
+
+       /* check if the link is up or not */
+       while (!dw_pcie_link_up(pp)) {
+               usleep_range(100, 1000);
+               if (--count)
+                       continue;
+               dev_err(pp->dev, "phy link never came up\n");
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+       struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
+       u32 offset = irq - ks_pcie->msi_host_irqs[0];
+       struct pcie_port *pp = &ks_pcie->pp;
+       struct irq_chip *chip = irq_desc_get_chip(desc);
+
+       dev_dbg(pp->dev, "ks_pci_msi_irq_handler, irq %d\n", irq);
+
+       /*
+        * The chained irq handler installation would have replaced normal
+        * interrupt driver handler so we need to take care of mask/unmask and
+        * ack operation.
+        */
+       chained_irq_enter(chip, desc);
+       ks_dw_pcie_handle_msi_irq(ks_pcie, offset);
+       chained_irq_exit(chip, desc);
+}
+
+/**
+ * ks_pcie_legacy_irq_handler() - Handle legacy interrupt
+ * @irq: IRQ line for legacy interrupts
+ * @desc: Pointer to irq descriptor
+ *
+ * Traverse through pending legacy interrupts and invoke handler for each. Also
+ * takes care of interrupt controller level mask/ack operation.
+ */
+static void ks_pcie_legacy_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+       struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
+       struct pcie_port *pp = &ks_pcie->pp;
+       u32 irq_offset = irq - ks_pcie->legacy_host_irqs[0];
+       struct irq_chip *chip = irq_desc_get_chip(desc);
+
+       dev_dbg(pp->dev, ": Handling legacy irq %d\n", irq);
+
+       /*
+        * The chained irq handler installation would have replaced normal
+        * interrupt driver handler so we need to take care of mask/unmask and
+        * ack operation.
+        */
+       chained_irq_enter(chip, desc);
+       ks_dw_pcie_handle_legacy_irq(ks_pcie, irq_offset);
+       chained_irq_exit(chip, desc);
+}
+
+static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie,
+                                          char *controller, int *num_irqs)
+{
+       int temp, max_host_irqs, legacy = 1, *host_irqs, ret = -EINVAL;
+       struct device *dev = ks_pcie->pp.dev;
+       struct device_node *np_pcie = dev->of_node, **np_temp;
+
+       if (!strcmp(controller, "msi-interrupt-controller"))
+               legacy = 0;
+
+       if (legacy) {
+               np_temp = &ks_pcie->legacy_intc_np;
+               max_host_irqs = MAX_LEGACY_HOST_IRQS;
+               host_irqs = &ks_pcie->legacy_host_irqs[0];
+       } else {
+               np_temp = &ks_pcie->msi_intc_np;
+               max_host_irqs = MAX_MSI_HOST_IRQS;
+               host_irqs =  &ks_pcie->msi_host_irqs[0];
+       }
+
+       /* interrupt controller is in a child node */
+       *np_temp = of_find_node_by_name(np_pcie, controller);
+       if (!(*np_temp)) {
+               dev_err(dev, "Node for %s is absent\n", controller);
+               goto out;
+       }
+       temp = of_irq_count(*np_temp);
+       if (!temp)
+               goto out;
+       if (temp > max_host_irqs)
+               dev_warn(dev, "Too many %s interrupts defined %u\n",
+                       (legacy ? "legacy" : "MSI"), temp);
+
+       /*
+        * support upto max_host_irqs. In dt from index 0 to 3 (legacy) or 0 to
+        * 7 (MSI)
+        */
+       for (temp = 0; temp < max_host_irqs; temp++) {
+               host_irqs[temp] = irq_of_parse_and_map(*np_temp, temp);
+               if (host_irqs[temp] < 0)
+                       break;
+       }
+       if (temp) {
+               *num_irqs = temp;
+               ret = 0;
+       }
+out:
+       return ret;
+}
+
+static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie)
+{
+       int i;
+
+       /* Legacy IRQ */
+       for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
+               irq_set_handler_data(ks_pcie->legacy_host_irqs[i], ks_pcie);
+               irq_set_chained_handler(ks_pcie->legacy_host_irqs[i],
+                                       ks_pcie_legacy_irq_handler);
+       }
+       ks_dw_pcie_enable_legacy_irqs(ks_pcie);
+
+       /* MSI IRQ */
+       if (IS_ENABLED(CONFIG_PCI_MSI)) {
+               for (i = 0; i < ks_pcie->num_msi_host_irqs; i++) {
+                       irq_set_chained_handler(ks_pcie->msi_host_irqs[i],
+                                               ks_pcie_msi_irq_handler);
+                       irq_set_handler_data(ks_pcie->msi_host_irqs[i],
+                                            ks_pcie);
+               }
+       }
+}
+
+/*
+ * When a PCI device does not exist during config cycles, keystone host gets a
+ * bus error instead of returning 0xffffffff. This handler always returns 0
+ * for this kind of faults.
+ */
+static int keystone_pcie_fault(unsigned long addr, unsigned int fsr,
+                               struct pt_regs *regs)
+{
+       unsigned long instr = *(unsigned long *) instruction_pointer(regs);
+
+       if ((instr & 0x0e100090) == 0x00100090) {
+               int reg = (instr >> 12) & 15;
+
+               regs->uregs[reg] = -1;
+               regs->ARM_pc += 4;
+       }
+
+       return 0;
+}
+
+static void __init ks_pcie_host_init(struct pcie_port *pp)
+{
+       u32 vendor_device_id, val;
+       struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+       ks_pcie_establish_link(ks_pcie);
+       ks_dw_pcie_setup_rc_app_regs(ks_pcie);
+       ks_pcie_setup_interrupts(ks_pcie);
+       writew(PCI_IO_RANGE_TYPE_32 | (PCI_IO_RANGE_TYPE_32 << 8),
+                       pp->dbi_base + PCI_IO_BASE);
+
+       /* update the Vendor ID */
+       vendor_device_id = readl(ks_pcie->va_reg_pciid);
+       writew((vendor_device_id >> 16), pp->dbi_base + PCI_DEVICE_ID);
+
+       /* update the DEV_STAT_CTRL to publish right mrrs */
+       val = readl(pp->dbi_base + PCIE_CAP_BASE + PCI_EXP_DEVCTL);
+       val &= ~PCI_EXP_DEVCTL_READRQ;
+       /* set the mrrs to 256 bytes */
+       val |= BIT(12);
+       writel(val, pp->dbi_base + PCIE_CAP_BASE + PCI_EXP_DEVCTL);
+
+       /*
+        * PCIe access errors that result into OCP errors are caught by ARM as
+        * "External aborts"
+        */
+       hook_fault_code(17, keystone_pcie_fault, SIGBUS, 0,
+                       "Asynchronous external abort");
+}
+
+static struct pcie_host_ops keystone_pcie_host_ops = {
+       .rd_other_conf = ks_dw_pcie_rd_other_conf,
+       .wr_other_conf = ks_dw_pcie_wr_other_conf,
+       .link_up = ks_dw_pcie_link_up,
+       .host_init = ks_pcie_host_init,
+       .msi_set_irq = ks_dw_pcie_msi_set_irq,
+       .msi_clear_irq = ks_dw_pcie_msi_clear_irq,
+       .get_msi_data = ks_dw_pcie_get_msi_data,
+};
+
+static int __init ks_add_pcie_port(struct keystone_pcie *ks_pcie,
+                        struct platform_device *pdev)
+{
+       struct pcie_port *pp = &ks_pcie->pp;
+       int ret;
+
+       ret = ks_pcie_get_irq_controller_info(ks_pcie,
+                                       "legacy-interrupt-controller",
+                                       &ks_pcie->num_legacy_host_irqs);
+       if (ret)
+               return ret;
+
+       if (IS_ENABLED(CONFIG_PCI_MSI)) {
+               ret = ks_pcie_get_irq_controller_info(ks_pcie,
+                                               "msi-interrupt-controller",
+                                               &ks_pcie->num_msi_host_irqs);
+               if (ret)
+                       return ret;
+       }
+
+       pp->root_bus_nr = -1;
+       pp->ops = &keystone_pcie_host_ops;
+       ret = ks_dw_pcie_host_init(ks_pcie, ks_pcie->msi_intc_np);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to initialize host\n");
+               return ret;
+       }
+
+       return ret;
+}
+
+static const struct of_device_id ks_pcie_of_match[] = {
+       {
+               .type = "pci",
+               .compatible = "ti,keystone-pcie",
+       },
+       { },
+};
+MODULE_DEVICE_TABLE(of, ks_pcie_of_match);
+
+static int __exit ks_pcie_remove(struct platform_device *pdev)
+{
+       struct keystone_pcie *ks_pcie = platform_get_drvdata(pdev);
+
+       clk_disable_unprepare(ks_pcie->clk);
+
+       return 0;
+}
+
+static int __init ks_pcie_probe(struct platform_device *pdev)
+{
+       struct device_node *np = pdev->dev.of_node;
+       struct device *dev = &pdev->dev;
+       struct keystone_pcie *ks_pcie;
+       struct pcie_port *pp;
+       struct resource *res;
+       void __iomem *reg_p;
+       struct phy *phy;
+       int ret = 0;
+       u32 val;
+
+       ks_pcie = devm_kzalloc(&pdev->dev, sizeof(*ks_pcie),
+                               GFP_KERNEL);
+       if (!ks_pcie) {
+               dev_err(dev, "no memory for keystone pcie\n");
+               return -ENOMEM;
+       }
+       pp = &ks_pcie->pp;
+
+       /* initialize SerDes Phy if present */
+       phy = devm_phy_get(dev, "pcie-phy");
+       if (!IS_ERR_OR_NULL(phy)) {
+               ret = phy_init(phy);
+               if (ret < 0)
+                       return ret;
+       }
+
+       /* index 2 is the devcfg register for RC mode settings */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+       reg_p = devm_ioremap_resource(dev, res);
+       if (IS_ERR(reg_p))
+               return PTR_ERR(reg_p);
+
+       /* enable RC mode in devcfg */
+       val = readl(reg_p);
+       val &= ~PCIE_MODE_MASK;
+       val |= PCIE_RC_MODE;
+       writel(val, reg_p);
+
+       /* index 3 is to read PCI DEVICE_ID */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+       reg_p = devm_ioremap_resource(dev, res);
+       if (IS_ERR(reg_p))
+               return PTR_ERR(reg_p);
+       ks_pcie->va_reg_pciid = reg_p;
+
+       /* check if we need to enable link training */
+       ks_pcie->link_train =
+               (of_get_property(np, "ti,enable-linktrain", NULL) != NULL);
+
+       pp->dev = dev;
+       platform_set_drvdata(pdev, ks_pcie);
+       ks_pcie->clk = devm_clk_get(dev, "pcie");
+       if (IS_ERR(ks_pcie->clk)) {
+               dev_err(dev, "Failed to get pcie rc clock\n");
+               return PTR_ERR(ks_pcie->clk);
+       }
+       ret = clk_prepare_enable(ks_pcie->clk);
+       if (ret)
+               return ret;
+
+       ret = ks_add_pcie_port(ks_pcie, pdev);
+       if (ret < 0)
+               goto fail_clk;
+
+       return 0;
+fail_clk:
+       clk_disable_unprepare(ks_pcie->clk);
+
+       return ret;
+}
+
+static struct platform_driver ks_pcie_driver __refdata = {
+       .probe  = ks_pcie_probe,
+       .remove = __exit_p(ks_pcie_remove),
+       .driver = {
+               .name   = "keystone-pcie",
+               .owner  = THIS_MODULE,
+               .of_match_table = of_match_ptr(ks_pcie_of_match),
+       },
+};
+
+module_platform_driver(ks_pcie_driver);
+
+MODULE_AUTHOR("Murali Karicheri <m-kariche...@ti.com>");
+MODULE_DESCRIPTION("Keystone PCIe host controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/host/pci-keystone.h b/drivers/pci/host/pci-keystone.h
new file mode 100644
index 0000000..b133f5c
--- /dev/null
+++ b/drivers/pci/host/pci-keystone.h
@@ -0,0 +1,56 @@
+/*
+ * Keystone PCI Controller's common includes
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ *             http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-kariche...@ti.com>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define MAX_LEGACY_IRQS                        4
+#define MAX_MSI_HOST_IRQS              8
+#define MAX_LEGACY_HOST_IRQS           4
+
+struct keystone_pcie {
+       struct  clk             *clk;
+       int                     link_train;
+       struct  pcie_port       pp;
+       void __iomem            *va_reg_pciid;
+
+       int                     num_legacy_host_irqs;
+       int                     legacy_host_irqs[MAX_LEGACY_HOST_IRQS];
+       struct                  device_node *legacy_intc_np;
+
+       int                     num_msi_host_irqs;
+       int                     msi_host_irqs[MAX_MSI_HOST_IRQS];
+       struct                  device_node *msi_intc_np;
+       struct irq_domain       *legacy_irq_domain;
+
+       /* Application register space */
+       void __iomem            *va_app_base;
+       struct resource         app;
+};
+
+/* Keystone DW specific MSI controller APIs/definitions */
+void ks_dw_pcie_handle_msi_irq(struct keystone_pcie *ks_pcie, int offset);
+u32 ks_dw_pcie_get_msi_data(struct pcie_port *pp);
+
+/* Keystone specific PCI controller APIs */
+void ks_dw_pcie_enable_legacy_irqs(struct keystone_pcie *ks_pcie);
+void ks_dw_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie, int offset);
+int  ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
+                       struct device_node *msi_intc_np);
+int ks_dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+               unsigned int devfn, int where, int size, u32 val);
+int ks_dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+               unsigned int devfn, int where, int size, u32 *val);
+void ks_dw_pcie_setup_rc_app_regs(struct keystone_pcie *ks_pcie);
+int ks_dw_pcie_link_up(struct pcie_port *pp);
+void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie);
+void ks_dw_pcie_msi_set_irq(struct pcie_port *pp, int irq);
+void ks_dw_pcie_msi_clear_irq(struct pcie_port *pp, int irq);
-- 
1.7.9.5

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