| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (c) 2017 Cadence |
| // Cadence PCIe host controller driver. |
| // Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com> |
| |
| #include <linux/kernel.h> |
| #include <linux/of_address.h> |
| #include <linux/of_pci.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| |
| #include "pcie-cadence.h" |
| |
| /** |
| * struct cdns_pcie_rc - private data for this PCIe Root Complex driver |
| * @pcie: Cadence PCIe controller |
| * @dev: pointer to PCIe device |
| * @cfg_res: start/end offsets in the physical system memory to map PCI |
| * configuration space accesses |
| * @bus_range: first/last buses behind the PCIe host controller |
| * @cfg_base: IO mapped window to access the PCI configuration space of a |
| * single function at a time |
| * @max_regions: maximum number of regions supported by the hardware |
| * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address |
| * translation (nbits sets into the "no BAR match" register) |
| * @vendor_id: PCI vendor ID |
| * @device_id: PCI device ID |
| */ |
| struct cdns_pcie_rc { |
| struct cdns_pcie pcie; |
| struct device *dev; |
| struct resource *cfg_res; |
| struct resource *bus_range; |
| void __iomem *cfg_base; |
| u32 max_regions; |
| u32 no_bar_nbits; |
| u16 vendor_id; |
| u16 device_id; |
| }; |
| |
| static void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn, |
| int where) |
| { |
| struct pci_host_bridge *bridge = pci_find_host_bridge(bus); |
| struct cdns_pcie_rc *rc = pci_host_bridge_priv(bridge); |
| struct cdns_pcie *pcie = &rc->pcie; |
| unsigned int busn = bus->number; |
| u32 addr0, desc0; |
| |
| if (busn == rc->bus_range->start) { |
| /* |
| * Only the root port (devfn == 0) is connected to this bus. |
| * All other PCI devices are behind some bridge hence on another |
| * bus. |
| */ |
| if (devfn) |
| return NULL; |
| |
| return pcie->reg_base + (where & 0xfff); |
| } |
| |
| /* Update Output registers for AXI region 0. */ |
| addr0 = CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_NBITS(12) | |
| CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_DEVFN(devfn) | |
| CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_BUS(busn); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(0), addr0); |
| |
| /* Configuration Type 0 or Type 1 access. */ |
| desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID | |
| CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0); |
| /* |
| * The bus number was already set once for all in desc1 by |
| * cdns_pcie_host_init_address_translation(). |
| */ |
| if (busn == rc->bus_range->start + 1) |
| desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE0; |
| else |
| desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE1; |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(0), desc0); |
| |
| return rc->cfg_base + (where & 0xfff); |
| } |
| |
| static struct pci_ops cdns_pcie_host_ops = { |
| .map_bus = cdns_pci_map_bus, |
| .read = pci_generic_config_read, |
| .write = pci_generic_config_write, |
| }; |
| |
| static const struct of_device_id cdns_pcie_host_of_match[] = { |
| { .compatible = "cdns,cdns-pcie-host" }, |
| |
| { }, |
| }; |
| |
| static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc) |
| { |
| struct cdns_pcie *pcie = &rc->pcie; |
| u32 value, ctrl; |
| |
| /* |
| * Set the root complex BAR configuration register: |
| * - disable both BAR0 and BAR1. |
| * - enable Prefetchable Memory Base and Limit registers in type 1 |
| * config space (64 bits). |
| * - enable IO Base and Limit registers in type 1 config |
| * space (32 bits). |
| */ |
| ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED; |
| value = CDNS_PCIE_LM_RC_BAR_CFG_BAR0_CTRL(ctrl) | |
| CDNS_PCIE_LM_RC_BAR_CFG_BAR1_CTRL(ctrl) | |
| CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_ENABLE | |
| CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_64BITS | |
| CDNS_PCIE_LM_RC_BAR_CFG_IO_ENABLE | |
| CDNS_PCIE_LM_RC_BAR_CFG_IO_32BITS; |
| cdns_pcie_writel(pcie, CDNS_PCIE_LM_RC_BAR_CFG, value); |
| |
| /* Set root port configuration space */ |
| if (rc->vendor_id != 0xffff) |
| cdns_pcie_rp_writew(pcie, PCI_VENDOR_ID, rc->vendor_id); |
| if (rc->device_id != 0xffff) |
| cdns_pcie_rp_writew(pcie, PCI_DEVICE_ID, rc->device_id); |
| |
| cdns_pcie_rp_writeb(pcie, PCI_CLASS_REVISION, 0); |
| cdns_pcie_rp_writeb(pcie, PCI_CLASS_PROG, 0); |
| cdns_pcie_rp_writew(pcie, PCI_CLASS_DEVICE, PCI_CLASS_BRIDGE_PCI); |
| |
| return 0; |
| } |
| |
| static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc) |
| { |
| struct cdns_pcie *pcie = &rc->pcie; |
| struct resource *cfg_res = rc->cfg_res; |
| struct resource *mem_res = pcie->mem_res; |
| struct resource *bus_range = rc->bus_range; |
| struct device *dev = rc->dev; |
| struct device_node *np = dev->of_node; |
| struct of_pci_range_parser parser; |
| struct of_pci_range range; |
| u32 addr0, addr1, desc1; |
| u64 cpu_addr; |
| int r, err; |
| |
| /* |
| * Reserve region 0 for PCI configure space accesses: |
| * OB_REGION_PCI_ADDR0 and OB_REGION_DESC0 are updated dynamically by |
| * cdns_pci_map_bus(), other region registers are set here once for all. |
| */ |
| addr1 = 0; /* Should be programmed to zero. */ |
| desc1 = CDNS_PCIE_AT_OB_REGION_DESC1_BUS(bus_range->start); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(0), addr1); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(0), desc1); |
| |
| cpu_addr = cfg_res->start - mem_res->start; |
| addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(12) | |
| (lower_32_bits(cpu_addr) & GENMASK(31, 8)); |
| addr1 = upper_32_bits(cpu_addr); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(0), addr0); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(0), addr1); |
| |
| err = of_pci_range_parser_init(&parser, np); |
| if (err) |
| return err; |
| |
| r = 1; |
| for_each_of_pci_range(&parser, &range) { |
| bool is_io; |
| |
| if (r >= rc->max_regions) |
| break; |
| |
| if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM) |
| is_io = false; |
| else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO) |
| is_io = true; |
| else |
| continue; |
| |
| cdns_pcie_set_outbound_region(pcie, 0, r, is_io, |
| range.cpu_addr, |
| range.pci_addr, |
| range.size); |
| r++; |
| } |
| |
| /* |
| * Set Root Port no BAR match Inbound Translation registers: |
| * needed for MSI and DMA. |
| * Root Port BAR0 and BAR1 are disabled, hence no need to set their |
| * inbound translation registers. |
| */ |
| addr0 = CDNS_PCIE_AT_IB_RP_BAR_ADDR0_NBITS(rc->no_bar_nbits); |
| addr1 = 0; |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR0(RP_NO_BAR), addr0); |
| cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR1(RP_NO_BAR), addr1); |
| |
| return 0; |
| } |
| |
| static int cdns_pcie_host_init(struct device *dev, |
| struct list_head *resources, |
| struct cdns_pcie_rc *rc) |
| { |
| struct resource *bus_range = NULL; |
| int err; |
| |
| /* Parse our PCI ranges and request their resources */ |
| err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range); |
| if (err) |
| return err; |
| |
| rc->bus_range = bus_range; |
| rc->pcie.bus = bus_range->start; |
| |
| err = cdns_pcie_host_init_root_port(rc); |
| if (err) |
| goto err_out; |
| |
| err = cdns_pcie_host_init_address_translation(rc); |
| if (err) |
| goto err_out; |
| |
| return 0; |
| |
| err_out: |
| pci_free_resource_list(resources); |
| return err; |
| } |
| |
| static int cdns_pcie_host_probe(struct platform_device *pdev) |
| { |
| const char *type; |
| struct device *dev = &pdev->dev; |
| struct device_node *np = dev->of_node; |
| struct pci_host_bridge *bridge; |
| struct list_head resources; |
| struct cdns_pcie_rc *rc; |
| struct cdns_pcie *pcie; |
| struct resource *res; |
| int ret; |
| |
| bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc)); |
| if (!bridge) |
| return -ENOMEM; |
| |
| rc = pci_host_bridge_priv(bridge); |
| rc->dev = dev; |
| |
| pcie = &rc->pcie; |
| pcie->is_rc = true; |
| |
| rc->max_regions = 32; |
| of_property_read_u32(np, "cdns,max-outbound-regions", &rc->max_regions); |
| |
| rc->no_bar_nbits = 32; |
| of_property_read_u32(np, "cdns,no-bar-match-nbits", &rc->no_bar_nbits); |
| |
| rc->vendor_id = 0xffff; |
| of_property_read_u16(np, "vendor-id", &rc->vendor_id); |
| |
| rc->device_id = 0xffff; |
| of_property_read_u16(np, "device-id", &rc->device_id); |
| |
| type = of_get_property(np, "device_type", NULL); |
| if (!type || strcmp(type, "pci")) { |
| dev_err(dev, "invalid \"device_type\" %s\n", type); |
| return -EINVAL; |
| } |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg"); |
| pcie->reg_base = devm_ioremap_resource(dev, res); |
| if (IS_ERR(pcie->reg_base)) { |
| dev_err(dev, "missing \"reg\"\n"); |
| return PTR_ERR(pcie->reg_base); |
| } |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg"); |
| rc->cfg_base = devm_pci_remap_cfg_resource(dev, res); |
| if (IS_ERR(rc->cfg_base)) { |
| dev_err(dev, "missing \"cfg\"\n"); |
| return PTR_ERR(rc->cfg_base); |
| } |
| rc->cfg_res = res; |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem"); |
| if (!res) { |
| dev_err(dev, "missing \"mem\"\n"); |
| return -EINVAL; |
| } |
| pcie->mem_res = res; |
| |
| pm_runtime_enable(dev); |
| ret = pm_runtime_get_sync(dev); |
| if (ret < 0) { |
| dev_err(dev, "pm_runtime_get_sync() failed\n"); |
| goto err_get_sync; |
| } |
| |
| ret = cdns_pcie_host_init(dev, &resources, rc); |
| if (ret) |
| goto err_init; |
| |
| list_splice_init(&resources, &bridge->windows); |
| bridge->dev.parent = dev; |
| bridge->busnr = pcie->bus; |
| bridge->ops = &cdns_pcie_host_ops; |
| bridge->map_irq = of_irq_parse_and_map_pci; |
| bridge->swizzle_irq = pci_common_swizzle; |
| |
| ret = pci_host_probe(bridge); |
| if (ret < 0) |
| goto err_host_probe; |
| |
| return 0; |
| |
| err_host_probe: |
| pci_free_resource_list(&resources); |
| |
| err_init: |
| pm_runtime_put_sync(dev); |
| |
| err_get_sync: |
| pm_runtime_disable(dev); |
| |
| return ret; |
| } |
| |
| static struct platform_driver cdns_pcie_host_driver = { |
| .driver = { |
| .name = "cdns-pcie-host", |
| .of_match_table = cdns_pcie_host_of_match, |
| }, |
| .probe = cdns_pcie_host_probe, |
| }; |
| builtin_platform_driver(cdns_pcie_host_driver); |