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-rw-r--r--arch/mips/pci/pci-ar71xx.c401
1 files changed, 401 insertions, 0 deletions
diff --git a/arch/mips/pci/pci-ar71xx.c b/arch/mips/pci/pci-ar71xx.c
new file mode 100644
index 000000000..118760b3f
--- /dev/null
+++ b/arch/mips/pci/pci-ar71xx.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Atheros AR71xx PCI host controller driver
+ *
+ * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ *
+ * Parts of this file are based on Atheros' 2.6.15 BSP
+ */
+
+#include <linux/resource.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+
+#include <asm/mach-ath79/ar71xx_regs.h>
+#include <asm/mach-ath79/ath79.h>
+
+#define AR71XX_PCI_REG_CRP_AD_CBE 0x00
+#define AR71XX_PCI_REG_CRP_WRDATA 0x04
+#define AR71XX_PCI_REG_CRP_RDDATA 0x08
+#define AR71XX_PCI_REG_CFG_AD 0x0c
+#define AR71XX_PCI_REG_CFG_CBE 0x10
+#define AR71XX_PCI_REG_CFG_WRDATA 0x14
+#define AR71XX_PCI_REG_CFG_RDDATA 0x18
+#define AR71XX_PCI_REG_PCI_ERR 0x1c
+#define AR71XX_PCI_REG_PCI_ERR_ADDR 0x20
+#define AR71XX_PCI_REG_AHB_ERR 0x24
+#define AR71XX_PCI_REG_AHB_ERR_ADDR 0x28
+
+#define AR71XX_PCI_CRP_CMD_WRITE 0x00010000
+#define AR71XX_PCI_CRP_CMD_READ 0x00000000
+#define AR71XX_PCI_CFG_CMD_READ 0x0000000a
+#define AR71XX_PCI_CFG_CMD_WRITE 0x0000000b
+
+#define AR71XX_PCI_INT_CORE BIT(4)
+#define AR71XX_PCI_INT_DEV2 BIT(2)
+#define AR71XX_PCI_INT_DEV1 BIT(1)
+#define AR71XX_PCI_INT_DEV0 BIT(0)
+
+#define AR71XX_PCI_IRQ_COUNT 5
+
+struct ar71xx_pci_controller {
+ void __iomem *cfg_base;
+ int irq;
+ int irq_base;
+ struct pci_controller pci_ctrl;
+ struct resource io_res;
+ struct resource mem_res;
+};
+
+/* Byte lane enable bits */
+static const u8 ar71xx_pci_ble_table[4][4] = {
+ {0x0, 0xf, 0xf, 0xf},
+ {0xe, 0xd, 0xb, 0x7},
+ {0xc, 0xf, 0x3, 0xf},
+ {0xf, 0xf, 0xf, 0xf},
+};
+
+static const u32 ar71xx_pci_read_mask[8] = {
+ 0, 0xff, 0xffff, 0, 0xffffffff, 0, 0, 0
+};
+
+static inline u32 ar71xx_pci_get_ble(int where, int size, int local)
+{
+ u32 t;
+
+ t = ar71xx_pci_ble_table[size & 3][where & 3];
+ BUG_ON(t == 0xf);
+ t <<= (local) ? 20 : 4;
+
+ return t;
+}
+
+static inline u32 ar71xx_pci_bus_addr(struct pci_bus *bus, unsigned int devfn,
+ int where)
+{
+ u32 ret;
+
+ if (!bus->number) {
+ /* type 0 */
+ ret = (1 << PCI_SLOT(devfn)) | (PCI_FUNC(devfn) << 8) |
+ (where & ~3);
+ } else {
+ /* type 1 */
+ ret = (bus->number << 16) | (PCI_SLOT(devfn) << 11) |
+ (PCI_FUNC(devfn) << 8) | (where & ~3) | 1;
+ }
+
+ return ret;
+}
+
+static inline struct ar71xx_pci_controller *
+pci_bus_to_ar71xx_controller(struct pci_bus *bus)
+{
+ struct pci_controller *hose;
+
+ hose = (struct pci_controller *) bus->sysdata;
+ return container_of(hose, struct ar71xx_pci_controller, pci_ctrl);
+}
+
+static int ar71xx_pci_check_error(struct ar71xx_pci_controller *apc, int quiet)
+{
+ void __iomem *base = apc->cfg_base;
+ u32 pci_err;
+ u32 ahb_err;
+
+ pci_err = __raw_readl(base + AR71XX_PCI_REG_PCI_ERR) & 3;
+ if (pci_err) {
+ if (!quiet) {
+ u32 addr;
+
+ addr = __raw_readl(base + AR71XX_PCI_REG_PCI_ERR_ADDR);
+ pr_crit("ar71xx: %s bus error %d at addr 0x%x\n",
+ "PCI", pci_err, addr);
+ }
+
+ /* clear PCI error status */
+ __raw_writel(pci_err, base + AR71XX_PCI_REG_PCI_ERR);
+ }
+
+ ahb_err = __raw_readl(base + AR71XX_PCI_REG_AHB_ERR) & 1;
+ if (ahb_err) {
+ if (!quiet) {
+ u32 addr;
+
+ addr = __raw_readl(base + AR71XX_PCI_REG_AHB_ERR_ADDR);
+ pr_crit("ar71xx: %s bus error %d at addr 0x%x\n",
+ "AHB", ahb_err, addr);
+ }
+
+ /* clear AHB error status */
+ __raw_writel(ahb_err, base + AR71XX_PCI_REG_AHB_ERR);
+ }
+
+ return !!(ahb_err | pci_err);
+}
+
+static inline void ar71xx_pci_local_write(struct ar71xx_pci_controller *apc,
+ int where, int size, u32 value)
+{
+ void __iomem *base = apc->cfg_base;
+ u32 ad_cbe;
+
+ value = value << (8 * (where & 3));
+
+ ad_cbe = AR71XX_PCI_CRP_CMD_WRITE | (where & ~3);
+ ad_cbe |= ar71xx_pci_get_ble(where, size, 1);
+
+ __raw_writel(ad_cbe, base + AR71XX_PCI_REG_CRP_AD_CBE);
+ __raw_writel(value, base + AR71XX_PCI_REG_CRP_WRDATA);
+}
+
+static inline int ar71xx_pci_set_cfgaddr(struct pci_bus *bus,
+ unsigned int devfn,
+ int where, int size, u32 cmd)
+{
+ struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus);
+ void __iomem *base = apc->cfg_base;
+ u32 addr;
+
+ addr = ar71xx_pci_bus_addr(bus, devfn, where);
+
+ __raw_writel(addr, base + AR71XX_PCI_REG_CFG_AD);
+ __raw_writel(cmd | ar71xx_pci_get_ble(where, size, 0),
+ base + AR71XX_PCI_REG_CFG_CBE);
+
+ return ar71xx_pci_check_error(apc, 1);
+}
+
+static int ar71xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *value)
+{
+ struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus);
+ void __iomem *base = apc->cfg_base;
+ u32 data;
+ int err;
+ int ret;
+
+ ret = PCIBIOS_SUCCESSFUL;
+ data = ~0;
+
+ err = ar71xx_pci_set_cfgaddr(bus, devfn, where, size,
+ AR71XX_PCI_CFG_CMD_READ);
+ if (err)
+ ret = PCIBIOS_DEVICE_NOT_FOUND;
+ else
+ data = __raw_readl(base + AR71XX_PCI_REG_CFG_RDDATA);
+
+ *value = (data >> (8 * (where & 3))) & ar71xx_pci_read_mask[size & 7];
+
+ return ret;
+}
+
+static int ar71xx_pci_write_config(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 value)
+{
+ struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus);
+ void __iomem *base = apc->cfg_base;
+ int err;
+ int ret;
+
+ value = value << (8 * (where & 3));
+ ret = PCIBIOS_SUCCESSFUL;
+
+ err = ar71xx_pci_set_cfgaddr(bus, devfn, where, size,
+ AR71XX_PCI_CFG_CMD_WRITE);
+ if (err)
+ ret = PCIBIOS_DEVICE_NOT_FOUND;
+ else
+ __raw_writel(value, base + AR71XX_PCI_REG_CFG_WRDATA);
+
+ return ret;
+}
+
+static struct pci_ops ar71xx_pci_ops = {
+ .read = ar71xx_pci_read_config,
+ .write = ar71xx_pci_write_config,
+};
+
+static void ar71xx_pci_irq_handler(struct irq_desc *desc)
+{
+ struct ar71xx_pci_controller *apc;
+ void __iomem *base = ath79_reset_base;
+ u32 pending;
+
+ apc = irq_desc_get_handler_data(desc);
+
+ pending = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_STATUS) &
+ __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+
+ if (pending & AR71XX_PCI_INT_DEV0)
+ generic_handle_irq(apc->irq_base + 0);
+
+ else if (pending & AR71XX_PCI_INT_DEV1)
+ generic_handle_irq(apc->irq_base + 1);
+
+ else if (pending & AR71XX_PCI_INT_DEV2)
+ generic_handle_irq(apc->irq_base + 2);
+
+ else if (pending & AR71XX_PCI_INT_CORE)
+ generic_handle_irq(apc->irq_base + 4);
+
+ else
+ spurious_interrupt();
+}
+
+static void ar71xx_pci_irq_unmask(struct irq_data *d)
+{
+ struct ar71xx_pci_controller *apc;
+ unsigned int irq;
+ void __iomem *base = ath79_reset_base;
+ u32 t;
+
+ apc = irq_data_get_irq_chip_data(d);
+ irq = d->irq - apc->irq_base;
+
+ t = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+ __raw_writel(t | (1 << irq), base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+
+ /* flush write */
+ __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+}
+
+static void ar71xx_pci_irq_mask(struct irq_data *d)
+{
+ struct ar71xx_pci_controller *apc;
+ unsigned int irq;
+ void __iomem *base = ath79_reset_base;
+ u32 t;
+
+ apc = irq_data_get_irq_chip_data(d);
+ irq = d->irq - apc->irq_base;
+
+ t = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+ __raw_writel(t & ~(1 << irq), base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+
+ /* flush write */
+ __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+}
+
+static struct irq_chip ar71xx_pci_irq_chip = {
+ .name = "AR71XX PCI",
+ .irq_mask = ar71xx_pci_irq_mask,
+ .irq_unmask = ar71xx_pci_irq_unmask,
+ .irq_mask_ack = ar71xx_pci_irq_mask,
+};
+
+static void ar71xx_pci_irq_init(struct ar71xx_pci_controller *apc)
+{
+ void __iomem *base = ath79_reset_base;
+ int i;
+
+ __raw_writel(0, base + AR71XX_RESET_REG_PCI_INT_ENABLE);
+ __raw_writel(0, base + AR71XX_RESET_REG_PCI_INT_STATUS);
+
+ BUILD_BUG_ON(ATH79_PCI_IRQ_COUNT < AR71XX_PCI_IRQ_COUNT);
+
+ apc->irq_base = ATH79_PCI_IRQ_BASE;
+ for (i = apc->irq_base;
+ i < apc->irq_base + AR71XX_PCI_IRQ_COUNT; i++) {
+ irq_set_chip_and_handler(i, &ar71xx_pci_irq_chip,
+ handle_level_irq);
+ irq_set_chip_data(i, apc);
+ }
+
+ irq_set_chained_handler_and_data(apc->irq, ar71xx_pci_irq_handler,
+ apc);
+}
+
+static void ar71xx_pci_reset(void)
+{
+ ath79_device_reset_set(AR71XX_RESET_PCI_BUS | AR71XX_RESET_PCI_CORE);
+ mdelay(100);
+
+ ath79_device_reset_clear(AR71XX_RESET_PCI_BUS | AR71XX_RESET_PCI_CORE);
+ mdelay(100);
+
+ ath79_ddr_set_pci_windows();
+ mdelay(100);
+}
+
+static int ar71xx_pci_probe(struct platform_device *pdev)
+{
+ struct ar71xx_pci_controller *apc;
+ struct resource *res;
+ u32 t;
+
+ apc = devm_kzalloc(&pdev->dev, sizeof(struct ar71xx_pci_controller),
+ GFP_KERNEL);
+ if (!apc)
+ return -ENOMEM;
+
+ apc->cfg_base = devm_platform_ioremap_resource_byname(pdev,
+ "cfg_base");
+ if (IS_ERR(apc->cfg_base))
+ return PTR_ERR(apc->cfg_base);
+
+ apc->irq = platform_get_irq(pdev, 0);
+ if (apc->irq < 0)
+ return -EINVAL;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_IO, "io_base");
+ if (!res)
+ return -EINVAL;
+
+ apc->io_res.parent = res;
+ apc->io_res.name = "PCI IO space";
+ apc->io_res.start = res->start;
+ apc->io_res.end = res->end;
+ apc->io_res.flags = IORESOURCE_IO;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem_base");
+ if (!res)
+ return -EINVAL;
+
+ apc->mem_res.parent = res;
+ apc->mem_res.name = "PCI memory space";
+ apc->mem_res.start = res->start;
+ apc->mem_res.end = res->end;
+ apc->mem_res.flags = IORESOURCE_MEM;
+
+ ar71xx_pci_reset();
+
+ /* setup COMMAND register */
+ t = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE
+ | PCI_COMMAND_PARITY | PCI_COMMAND_SERR | PCI_COMMAND_FAST_BACK;
+ ar71xx_pci_local_write(apc, PCI_COMMAND, 4, t);
+
+ /* clear bus errors */
+ ar71xx_pci_check_error(apc, 1);
+
+ ar71xx_pci_irq_init(apc);
+
+ apc->pci_ctrl.pci_ops = &ar71xx_pci_ops;
+ apc->pci_ctrl.mem_resource = &apc->mem_res;
+ apc->pci_ctrl.io_resource = &apc->io_res;
+
+ register_pci_controller(&apc->pci_ctrl);
+
+ return 0;
+}
+
+static struct platform_driver ar71xx_pci_driver = {
+ .probe = ar71xx_pci_probe,
+ .driver = {
+ .name = "ar71xx-pci",
+ },
+};
+
+static int __init ar71xx_pci_init(void)
+{
+ return platform_driver_register(&ar71xx_pci_driver);
+}
+
+postcore_initcall(ar71xx_pci_init);