diff options
Diffstat (limited to 'drivers/pci/controller/pci-loongson.c')
| -rw-r--r-- | drivers/pci/controller/pci-loongson.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c new file mode 100644 index 0000000000..8b34ccff07 --- /dev/null +++ b/drivers/pci/controller/pci-loongson.c @@ -0,0 +1,397 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Loongson PCI Host Controller Driver + * + * Copyright (C) 2020 Jiaxun Yang <jiaxun.yang@flygoat.com> + */ + +#include <linux/of.h> +#include <linux/of_pci.h> +#include <linux/pci.h> +#include <linux/pci_ids.h> +#include <linux/pci-acpi.h> +#include <linux/pci-ecam.h> + +#include "../pci.h" + +/* Device IDs */ +#define DEV_LS2K_PCIE_PORT0 0x1a05 +#define DEV_LS7A_PCIE_PORT0 0x7a09 +#define DEV_LS7A_PCIE_PORT1 0x7a19 +#define DEV_LS7A_PCIE_PORT2 0x7a29 +#define DEV_LS7A_PCIE_PORT3 0x7a39 +#define DEV_LS7A_PCIE_PORT4 0x7a49 +#define DEV_LS7A_PCIE_PORT5 0x7a59 +#define DEV_LS7A_PCIE_PORT6 0x7a69 + +#define DEV_LS2K_APB 0x7a02 +#define DEV_LS7A_GMAC 0x7a03 +#define DEV_LS7A_DC1 0x7a06 +#define DEV_LS7A_LPC 0x7a0c +#define DEV_LS7A_AHCI 0x7a08 +#define DEV_LS7A_CONF 0x7a10 +#define DEV_LS7A_GNET 0x7a13 +#define DEV_LS7A_EHCI 0x7a14 +#define DEV_LS7A_DC2 0x7a36 +#define DEV_LS7A_HDMI 0x7a37 + +#define FLAG_CFG0 BIT(0) +#define FLAG_CFG1 BIT(1) +#define FLAG_DEV_FIX BIT(2) +#define FLAG_DEV_HIDDEN BIT(3) + +struct loongson_pci_data { + u32 flags; + struct pci_ops *ops; +}; + +struct loongson_pci { + void __iomem *cfg0_base; + void __iomem *cfg1_base; + struct platform_device *pdev; + const struct loongson_pci_data *data; +}; + +/* Fixup wrong class code in PCIe bridges */ +static void bridge_class_quirk(struct pci_dev *dev) +{ + dev->class = PCI_CLASS_BRIDGE_PCI_NORMAL; +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT0, bridge_class_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT1, bridge_class_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT2, bridge_class_quirk); + +static void system_bus_quirk(struct pci_dev *pdev) +{ + /* + * The address space consumed by these devices is outside the + * resources of the host bridge. + */ + pdev->mmio_always_on = 1; + pdev->non_compliant_bars = 1; +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS2K_APB, system_bus_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_CONF, system_bus_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_LPC, system_bus_quirk); + +/* + * Some Loongson PCIe ports have hardware limitations on their Maximum Read + * Request Size. They can't handle anything larger than this. Sane + * firmware will set proper MRRS at boot, so we only need no_inc_mrrs for + * bridges. However, some MIPS Loongson firmware doesn't set MRRS properly, + * so we have to enforce maximum safe MRRS, which is 256 bytes. + */ +#ifdef CONFIG_MIPS +static void loongson_set_min_mrrs_quirk(struct pci_dev *pdev) +{ + struct pci_bus *bus = pdev->bus; + struct pci_dev *bridge; + static const struct pci_device_id bridge_devids[] = { + { PCI_VDEVICE(LOONGSON, DEV_LS2K_PCIE_PORT0) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT0) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT1) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT2) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT3) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT4) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT5) }, + { PCI_VDEVICE(LOONGSON, DEV_LS7A_PCIE_PORT6) }, + { 0, }, + }; + + /* look for the matching bridge */ + while (!pci_is_root_bus(bus)) { + bridge = bus->self; + bus = bus->parent; + + if (pci_match_id(bridge_devids, bridge)) { + if (pcie_get_readrq(pdev) > 256) { + pci_info(pdev, "limiting MRRS to 256\n"); + pcie_set_readrq(pdev, 256); + } + break; + } + } +} +DECLARE_PCI_FIXUP_ENABLE(PCI_ANY_ID, PCI_ANY_ID, loongson_set_min_mrrs_quirk); +#endif + +static void loongson_mrrs_quirk(struct pci_dev *pdev) +{ + struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); + + bridge->no_inc_mrrs = 1; +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS2K_PCIE_PORT0, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT0, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT1, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT2, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT3, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT4, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT5, loongson_mrrs_quirk); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_PCIE_PORT6, loongson_mrrs_quirk); + +static void loongson_pci_pin_quirk(struct pci_dev *pdev) +{ + pdev->pin = 1 + (PCI_FUNC(pdev->devfn) & 3); +} +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_DC1, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_DC2, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_GMAC, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_AHCI, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_EHCI, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_GNET, loongson_pci_pin_quirk); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, + DEV_LS7A_HDMI, loongson_pci_pin_quirk); + +static struct loongson_pci *pci_bus_to_loongson_pci(struct pci_bus *bus) +{ + struct pci_config_window *cfg; + + if (acpi_disabled) + return (struct loongson_pci *)(bus->sysdata); + + cfg = bus->sysdata; + return (struct loongson_pci *)(cfg->priv); +} + +static void __iomem *cfg0_map(struct loongson_pci *priv, struct pci_bus *bus, + unsigned int devfn, int where) +{ + unsigned long addroff = 0x0; + unsigned char busnum = bus->number; + + if (!pci_is_root_bus(bus)) { + addroff |= BIT(24); /* Type 1 Access */ + addroff |= (busnum << 16); + } + addroff |= (devfn << 8) | where; + return priv->cfg0_base + addroff; +} + +static void __iomem *cfg1_map(struct loongson_pci *priv, struct pci_bus *bus, + unsigned int devfn, int where) +{ + unsigned long addroff = 0x0; + unsigned char busnum = bus->number; + + if (!pci_is_root_bus(bus)) { + addroff |= BIT(28); /* Type 1 Access */ + addroff |= (busnum << 16); + } + addroff |= (devfn << 8) | (where & 0xff) | ((where & 0xf00) << 16); + return priv->cfg1_base + addroff; +} + +static bool pdev_may_exist(struct pci_bus *bus, unsigned int device, + unsigned int function) +{ + return !(pci_is_root_bus(bus) && + (device >= 9 && device <= 20) && (function > 0)); +} + +static void __iomem *pci_loongson_map_bus(struct pci_bus *bus, + unsigned int devfn, int where) +{ + unsigned int device = PCI_SLOT(devfn); + unsigned int function = PCI_FUNC(devfn); + struct loongson_pci *priv = pci_bus_to_loongson_pci(bus); + + /* + * Do not read more than one device on the bus other than + * the host bus. + */ + if ((priv->data->flags & FLAG_DEV_FIX) && bus->self) { + if (!pci_is_root_bus(bus) && (device > 0)) + return NULL; + } + + /* Don't access non-existent devices */ + if (priv->data->flags & FLAG_DEV_HIDDEN) { + if (!pdev_may_exist(bus, device, function)) + return NULL; + } + + /* CFG0 can only access standard space */ + if (where < PCI_CFG_SPACE_SIZE && priv->cfg0_base) + return cfg0_map(priv, bus, devfn, where); + + /* CFG1 can access extended space */ + if (where < PCI_CFG_SPACE_EXP_SIZE && priv->cfg1_base) + return cfg1_map(priv, bus, devfn, where); + + return NULL; +} + +#ifdef CONFIG_OF + +static int loongson_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +{ + int irq; + u8 val; + + irq = of_irq_parse_and_map_pci(dev, slot, pin); + if (irq > 0) + return irq; + + /* Care i8259 legacy systems */ + pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &val); + /* i8259 only have 15 IRQs */ + if (val > 15) + return 0; + + return val; +} + +/* LS2K/LS7A accept 8/16/32-bit PCI config operations */ +static struct pci_ops loongson_pci_ops = { + .map_bus = pci_loongson_map_bus, + .read = pci_generic_config_read, + .write = pci_generic_config_write, +}; + +/* RS780/SR5690 only accept 32-bit PCI config operations */ +static struct pci_ops loongson_pci_ops32 = { + .map_bus = pci_loongson_map_bus, + .read = pci_generic_config_read32, + .write = pci_generic_config_write32, +}; + +static const struct loongson_pci_data ls2k_pci_data = { + .flags = FLAG_CFG1 | FLAG_DEV_FIX | FLAG_DEV_HIDDEN, + .ops = &loongson_pci_ops, +}; + +static const struct loongson_pci_data ls7a_pci_data = { + .flags = FLAG_CFG1 | FLAG_DEV_FIX | FLAG_DEV_HIDDEN, + .ops = &loongson_pci_ops, +}; + +static const struct loongson_pci_data rs780e_pci_data = { + .flags = FLAG_CFG0, + .ops = &loongson_pci_ops32, +}; + +static const struct of_device_id loongson_pci_of_match[] = { + { .compatible = "loongson,ls2k-pci", + .data = &ls2k_pci_data, }, + { .compatible = "loongson,ls7a-pci", + .data = &ls7a_pci_data, }, + { .compatible = "loongson,rs780e-pci", + .data = &rs780e_pci_data, }, + {} +}; + +static int loongson_pci_probe(struct platform_device *pdev) +{ + struct loongson_pci *priv; + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node; + struct pci_host_bridge *bridge; + struct resource *regs; + + if (!node) + return -ENODEV; + + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*priv)); + if (!bridge) + return -ENODEV; + + priv = pci_host_bridge_priv(bridge); + priv->pdev = pdev; + priv->data = of_device_get_match_data(dev); + + if (priv->data->flags & FLAG_CFG0) { + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!regs) + dev_err(dev, "missing mem resources for cfg0\n"); + else { + priv->cfg0_base = devm_pci_remap_cfg_resource(dev, regs); + if (IS_ERR(priv->cfg0_base)) + return PTR_ERR(priv->cfg0_base); + } + } + + if (priv->data->flags & FLAG_CFG1) { + regs = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!regs) + dev_info(dev, "missing mem resource for cfg1\n"); + else { + priv->cfg1_base = devm_pci_remap_cfg_resource(dev, regs); + if (IS_ERR(priv->cfg1_base)) + priv->cfg1_base = NULL; + } + } + + bridge->sysdata = priv; + bridge->ops = priv->data->ops; + bridge->map_irq = loongson_map_irq; + + return pci_host_probe(bridge); +} + +static struct platform_driver loongson_pci_driver = { + .driver = { + .name = "loongson-pci", + .of_match_table = loongson_pci_of_match, + }, + .probe = loongson_pci_probe, +}; +builtin_platform_driver(loongson_pci_driver); + +#endif + +#ifdef CONFIG_ACPI + +static int loongson_pci_ecam_init(struct pci_config_window *cfg) +{ + struct device *dev = cfg->parent; + struct loongson_pci *priv; + struct loongson_pci_data *data; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + cfg->priv = priv; + data->flags = FLAG_CFG1 | FLAG_DEV_HIDDEN; + priv->data = data; + priv->cfg1_base = cfg->win - (cfg->busr.start << 16); + + return 0; +} + +const struct pci_ecam_ops loongson_pci_ecam_ops = { + .bus_shift = 16, + .init = loongson_pci_ecam_init, + .pci_ops = { + .map_bus = pci_loongson_map_bus, + .read = pci_generic_config_read, + .write = pci_generic_config_write, + } +}; + +#endif |