diff options
Diffstat (limited to 'drivers/pci/controller/pcie-cadence-host.c')
| -rw-r--r-- | drivers/pci/controller/pcie-cadence-host.c | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-cadence-host.c b/drivers/pci/controller/pcie-cadence-host.c new file mode 100644 index 000000000000..a4ebbd37b553 --- /dev/null +++ b/drivers/pci/controller/pcie-cadence-host.c @@ -0,0 +1,336 @@ +// 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); 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