diff options
Diffstat (limited to 'arch/loongarch/pci/acpi.c')
| -rw-r--r-- | arch/loongarch/pci/acpi.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/arch/loongarch/pci/acpi.c b/arch/loongarch/pci/acpi.c new file mode 100644 index 000000000..8235ec92b --- /dev/null +++ b/arch/loongarch/pci/acpi.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <linux/pci.h> +#include <linux/acpi.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/pci-acpi.h> +#include <linux/pci-ecam.h> + +#include <asm/pci.h> +#include <asm/numa.h> +#include <asm/loongson.h> + +struct pci_root_info { + struct acpi_pci_root_info common; + struct pci_config_window *cfg; +}; + +void pcibios_add_bus(struct pci_bus *bus) +{ + acpi_pci_add_bus(bus); +} + +int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) +{ + struct pci_config_window *cfg = bridge->bus->sysdata; + struct acpi_device *adev = to_acpi_device(cfg->parent); + struct device *bus_dev = &bridge->bus->dev; + + ACPI_COMPANION_SET(&bridge->dev, adev); + set_dev_node(bus_dev, pa_to_nid(cfg->res.start)); + + return 0; +} + +int acpi_pci_bus_find_domain_nr(struct pci_bus *bus) +{ + struct pci_config_window *cfg = bus->sysdata; + struct acpi_device *adev = to_acpi_device(cfg->parent); + struct acpi_pci_root *root = acpi_driver_data(adev); + + return root->segment; +} + +static void acpi_release_root_info(struct acpi_pci_root_info *ci) +{ + struct pci_root_info *info; + + info = container_of(ci, struct pci_root_info, common); + pci_ecam_free(info->cfg); + kfree(ci->ops); + kfree(info); +} + +static int acpi_prepare_root_resources(struct acpi_pci_root_info *ci) +{ + int status; + struct resource_entry *entry, *tmp; + struct acpi_device *device = ci->bridge; + + status = acpi_pci_probe_root_resources(ci); + if (status > 0) { + resource_list_for_each_entry_safe(entry, tmp, &ci->resources) { + if (entry->res->flags & IORESOURCE_MEM) { + entry->offset = ci->root->mcfg_addr & GENMASK_ULL(63, 40); + entry->res->start |= entry->offset; + entry->res->end |= entry->offset; + } + } + return status; + } + + resource_list_for_each_entry_safe(entry, tmp, &ci->resources) { + dev_dbg(&device->dev, + "host bridge window %pR (ignored)\n", entry->res); + resource_list_destroy_entry(entry); + } + + return 0; +} + +/* + * Create a PCI config space window + * - reserve mem region + * - alloc struct pci_config_window with space for all mappings + * - ioremap the config space + */ +static struct pci_config_window *arch_pci_ecam_create(struct device *dev, + struct resource *cfgres, struct resource *busr, const struct pci_ecam_ops *ops) +{ + int bsz, bus_range, err; + struct resource *conflict; + struct pci_config_window *cfg; + + if (busr->start > busr->end) + return ERR_PTR(-EINVAL); + + cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); + if (!cfg) + return ERR_PTR(-ENOMEM); + + cfg->parent = dev; + cfg->ops = ops; + cfg->busr.start = busr->start; + cfg->busr.end = busr->end; + cfg->busr.flags = IORESOURCE_BUS; + bus_range = resource_size(cfgres) >> ops->bus_shift; + + bsz = 1 << ops->bus_shift; + + cfg->res.start = cfgres->start; + cfg->res.end = cfgres->end; + cfg->res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; + cfg->res.name = "PCI ECAM"; + + conflict = request_resource_conflict(&iomem_resource, &cfg->res); + if (conflict) { + err = -EBUSY; + dev_err(dev, "can't claim ECAM area %pR: address conflict with %s %pR\n", + &cfg->res, conflict->name, conflict); + goto err_exit; + } + + cfg->win = pci_remap_cfgspace(cfgres->start, bus_range * bsz); + if (!cfg->win) + goto err_exit_iomap; + + if (ops->init) { + err = ops->init(cfg); + if (err) + goto err_exit; + } + dev_info(dev, "ECAM at %pR for %pR\n", &cfg->res, &cfg->busr); + + return cfg; + +err_exit_iomap: + err = -ENOMEM; + dev_err(dev, "ECAM ioremap failed\n"); +err_exit: + pci_ecam_free(cfg); + return ERR_PTR(err); +} + +/* + * Lookup the bus range for the domain in MCFG, and set up config space + * mapping. + */ +static struct pci_config_window * +pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root) +{ + int ret, bus_shift; + u16 seg = root->segment; + struct device *dev = &root->device->dev; + struct resource cfgres; + struct resource *bus_res = &root->secondary; + struct pci_config_window *cfg; + const struct pci_ecam_ops *ecam_ops; + + ret = pci_mcfg_lookup(root, &cfgres, &ecam_ops); + if (ret < 0) { + dev_err(dev, "%04x:%pR ECAM region not found, use default value\n", seg, bus_res); + ecam_ops = &loongson_pci_ecam_ops; + root->mcfg_addr = mcfg_addr_init(0); + } + + bus_shift = ecam_ops->bus_shift ? : 20; + + if (bus_shift == 20) + cfg = pci_ecam_create(dev, &cfgres, bus_res, ecam_ops); + else { + cfgres.start = root->mcfg_addr + (bus_res->start << bus_shift); + cfgres.end = cfgres.start + (resource_size(bus_res) << bus_shift) - 1; + cfgres.end |= BIT(28) + (((PCI_CFG_SPACE_EXP_SIZE - 1) & 0xf00) << 16); + cfgres.flags = IORESOURCE_MEM; + cfg = arch_pci_ecam_create(dev, &cfgres, bus_res, ecam_ops); + } + + if (IS_ERR(cfg)) { + dev_err(dev, "%04x:%pR error %ld mapping ECAM\n", seg, bus_res, PTR_ERR(cfg)); + return NULL; + } + + return cfg; +} + +struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) +{ + struct pci_bus *bus; + struct pci_root_info *info; + struct acpi_pci_root_ops *root_ops; + int domain = root->segment; + int busnum = root->secondary.start; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + pr_warn("pci_bus %04x:%02x: ignored (out of memory)\n", domain, busnum); + return NULL; + } + + root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL); + if (!root_ops) { + kfree(info); + return NULL; + } + + info->cfg = pci_acpi_setup_ecam_mapping(root); + if (!info->cfg) { + kfree(info); + kfree(root_ops); + return NULL; + } + + root_ops->release_info = acpi_release_root_info; + root_ops->prepare_resources = acpi_prepare_root_resources; + root_ops->pci_ops = (struct pci_ops *)&info->cfg->ops->pci_ops; + + bus = pci_find_bus(domain, busnum); + if (bus) { + memcpy(bus->sysdata, info->cfg, sizeof(struct pci_config_window)); + kfree(info); + } else { + struct pci_bus *child; + + bus = acpi_pci_root_create(root, root_ops, + &info->common, info->cfg); + if (!bus) { + kfree(info); + kfree(root_ops); + return NULL; + } + + pci_bus_size_bridges(bus); + pci_bus_assign_resources(bus); + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); + } + + return bus; +} |