[PATCH v6 4/5] PCI: add PCI controller for keystone PCIe h/w

From: Murali Karicheri
Date: Fri Jul 18 2014 - 11:16:53 EST


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-karicheri2@xxxxxx>
Acked-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>

CC: Russell King <linux@xxxxxxxxxxxxxxxx>
CC: Grant Likely <grant.likely@xxxxxxxxxx>
CC: Rob Herring <robh+dt@xxxxxxxxxx>
CC: Mohit Kumar <mohit.kumar@xxxxxx>
CC: Jingoo Han <jg1.han@xxxxxxxxxxx>
CC: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
CC: Pratyush Anand <pratyush.anand@xxxxxx>
CC: Richard Zhu <r65037@xxxxxxxxxxxxx>
CC: Kishon Vijay Abraham I <kishon@xxxxxx>
CC: Marek Vasut <marex@xxxxxxx>
CC: Arnd Bergmann <arnd@xxxxxxxx>
CC: Pawel Moll <pawel.moll@xxxxxxx>
CC: Mark Rutland <mark.rutland@xxxxxxx>
CC: Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx>
CC: Kumar Gala <galak@xxxxxxxxxxxxxx>
CC: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
CC: Grant Likely <grant.likely@xxxxxxxxxx>
---
.../devicetree/bindings/pci/pci-keystone.txt | 71 +++
drivers/pci/host/Kconfig | 5 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-keystone-dw.c | 516 ++++++++++++++++++++
drivers/pci/host/pci-keystone.c | 385 +++++++++++++++
drivers/pci/host/pci-keystone.h | 59 +++
6 files changed, 1037 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..9c96164
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pci-keystone.txt
@@ -0,0 +1,71 @@
+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
+
+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.
+
+Note for PCI driver usage
+=========================
+Driver requires pci=pcie_bus_perf in the bootargs for proper functioning.
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..b75582c
--- /dev/null
+++ b/drivers/pci/host/pci-keystone-dw.c
@@ -0,0 +1,516 @@
+/*
+ * Designware application register space functions for Keystone PCI controller
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ * http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@xxxxxx>
+ *
+ *
+ * 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,
+};
+
+int ks_dw_pcie_msi_host_init(struct pcie_port *pp,
+ struct msi_chip *chip)
+{
+ struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+ int i;
+
+ pp->irq_domain = irq_domain_add_linear(ks_pcie->msi_intc_np,
+ MAX_MSI_IRQS,
+ &ks_dw_pcie_msi_domain_ops,
+ chip);
+ if (!pp->irq_domain) {
+ dev_err(pp->dev, "irq domain init failed\n");
+ return -ENXIO;
+ }
+
+ for (i = 0; i < MAX_MSI_IRQS; i++)
+ irq_create_mapping(pp->irq_domain, i);
+
+ return 0;
+}
+
+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_setup() - 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_setup(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->va_cfg0_base;
+}
+
+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_setup(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_setup(ks_pcie, bus_num, devfn);
+
+ return dw_pcie_cfg_write(addr + (where & ~0x3), where, size, val);
+}
+
+/**
+ * ks_dw_pcie_v3_65_scan_bus() - keystone scan_bus post initialization
+ *
+ * This sets BAR0 to enable inbound access for MSI_IRQ register
+ */
+void ks_dw_pcie_v3_65_scan_bus(struct pcie_port *pp)
+{
+ struct keystone_pcie *ks_pcie = to_keystone_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_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);
+}
+
+/**
+ * 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);
+
+ /*
+ * we set these same and is used in pcie rd/wr_other_conf
+ * functions
+ */
+ pp->va_cfg0_base = pp->dbi_base + SPACE0_REMOTE_CFG_OFFSET;
+ pp->va_cfg1_base = pp->va_cfg0_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_host_init(pp);
+}
diff --git a/drivers/pci/host/pci-keystone.c b/drivers/pci/host/pci-keystone.c
new file mode 100644
index 0000000..341ced8
--- /dev/null
+++ b/drivers/pci/host/pci-keystone.c
@@ -0,0 +1,385 @@
+/*
+ * PCIe host controller driver for Texas Instruments Keystone SoCs
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ * http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@xxxxxx>
+ * 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,
+ .msi_host_init = ks_dw_pcie_msi_host_init,
+ .scan_bus = ks_dw_pcie_v3_65_scan_bus,
+};
+
+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-karicheri2@xxxxxx>");
+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..0bedfc5
--- /dev/null
+++ b/drivers/pci/host/pci-keystone.h
@@ -0,0 +1,59 @@
+/*
+ * Keystone PCI Controller's common includes
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ * http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@xxxxxx>
+ *
+ *
+ * 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);
+void ks_dw_pcie_v3_65_scan_bus(struct pcie_port *pp);
+int ks_dw_pcie_msi_host_init(struct pcie_port *pp,
+ struct msi_chip *chip);
--
1.7.9.5

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