diff options
Diffstat (limited to 'arch/arm64/kernel/pci.c')
| -rw-r--r-- | arch/arm64/kernel/pci.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c new file mode 100644 index 000000000..2276689b5 --- /dev/null +++ b/arch/arm64/kernel/pci.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Code borrowed from powerpc/kernel/pci-common.c + * + * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM + * Copyright (C) 2014 ARM Ltd. + */ + +#include <linux/acpi.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/of_pci.h> +#include <linux/of_platform.h> +#include <linux/pci.h> +#include <linux/pci-acpi.h> +#include <linux/pci-ecam.h> +#include <linux/slab.h> + +#ifdef CONFIG_ACPI +/* + * Try to assign the IRQ number when probing a new device + */ +int pcibios_alloc_irq(struct pci_dev *dev) +{ + if (!acpi_disabled) + acpi_pci_irq_enable(dev); + + return 0; +} +#endif + +/* + * raw_pci_read/write - Platform-specific PCI config space access. + */ +int raw_pci_read(unsigned int domain, unsigned int bus, + unsigned int devfn, int reg, int len, u32 *val) +{ + struct pci_bus *b = pci_find_bus(domain, bus); + + if (!b) + return PCIBIOS_DEVICE_NOT_FOUND; + return b->ops->read(b, devfn, reg, len, val); +} + +int raw_pci_write(unsigned int domain, unsigned int bus, + unsigned int devfn, int reg, int len, u32 val) +{ + struct pci_bus *b = pci_find_bus(domain, bus); + + if (!b) + return PCIBIOS_DEVICE_NOT_FOUND; + return b->ops->write(b, devfn, reg, len, val); +} + +#ifdef CONFIG_NUMA + +int pcibus_to_node(struct pci_bus *bus) +{ + return dev_to_node(&bus->dev); +} +EXPORT_SYMBOL(pcibus_to_node); + +#endif + +#ifdef CONFIG_ACPI + +struct acpi_pci_generic_root_info { + struct acpi_pci_root_info common; + struct pci_config_window *cfg; /* config space mapping */ +}; + +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; +} + +int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) +{ + struct pci_config_window *cfg; + struct acpi_device *adev; + struct device *bus_dev; + + if (acpi_disabled) + return 0; + + cfg = bridge->bus->sysdata; + + /* + * On Hyper-V there is no corresponding ACPI device for a root bridge, + * therefore ->parent is set as NULL by the driver. And set 'adev' as + * NULL in this case because there is no proper ACPI device. + */ + if (!cfg->parent) + adev = NULL; + else + adev = to_acpi_device(cfg->parent); + + bus_dev = &bridge->bus->dev; + + ACPI_COMPANION_SET(&bridge->dev, adev); + set_dev_node(bus_dev, acpi_get_node(acpi_device_handle(adev))); + + return 0; +} + +static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci) +{ + struct resource_entry *entry, *tmp; + int status; + + status = acpi_pci_probe_root_resources(ci); + resource_list_for_each_entry_safe(entry, tmp, &ci->resources) { + if (!(entry->res->flags & IORESOURCE_WINDOW)) + resource_list_destroy_entry(entry); + } + return status; +} + +/* + * 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) +{ + struct device *dev = &root->device->dev; + struct resource *bus_res = &root->secondary; + u16 seg = root->segment; + const struct pci_ecam_ops *ecam_ops; + struct resource cfgres; + struct acpi_device *adev; + struct pci_config_window *cfg; + int ret; + + ret = pci_mcfg_lookup(root, &cfgres, &ecam_ops); + if (ret) { + dev_err(dev, "%04x:%pR ECAM region not found\n", seg, bus_res); + return NULL; + } + + adev = acpi_resource_consumer(&cfgres); + if (adev) + dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres, + dev_name(&adev->dev)); + else + dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n", + &cfgres); + + cfg = 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; +} + +/* release_info: free resources allocated by init_info */ +static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) +{ + struct acpi_pci_generic_root_info *ri; + + ri = container_of(ci, struct acpi_pci_generic_root_info, common); + pci_ecam_free(ri->cfg); + kfree(ci->ops); + kfree(ri); +} + +/* Interface called from ACPI code to setup PCI host controller */ +struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) +{ + struct acpi_pci_generic_root_info *ri; + struct pci_bus *bus, *child; + struct acpi_pci_root_ops *root_ops; + struct pci_host_bridge *host; + + ri = kzalloc(sizeof(*ri), GFP_KERNEL); + if (!ri) + return NULL; + + root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL); + if (!root_ops) { + kfree(ri); + return NULL; + } + + ri->cfg = pci_acpi_setup_ecam_mapping(root); + if (!ri->cfg) { + kfree(ri); + kfree(root_ops); + return NULL; + } + + root_ops->release_info = pci_acpi_generic_release_info; + root_ops->prepare_resources = pci_acpi_root_prepare_resources; + root_ops->pci_ops = (struct pci_ops *)&ri->cfg->ops->pci_ops; + bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg); + if (!bus) + return NULL; + + /* If we must preserve the resource configuration, claim now */ + host = pci_find_host_bridge(bus); + if (host->preserve_config) + pci_bus_claim_resources(bus); + + /* + * Assign whatever was left unassigned. If we didn't claim above, + * this will reassign everything. + */ + pci_assign_unassigned_root_bus_resources(bus); + + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); + + return bus; +} + +void pcibios_add_bus(struct pci_bus *bus) +{ + acpi_pci_add_bus(bus); +} + +void pcibios_remove_bus(struct pci_bus *bus) +{ + acpi_pci_remove_bus(bus); +} + +#endif |