diff options
Diffstat (limited to 'drivers/pci/host/pci-host-common.c')
| -rw-r--r-- | drivers/pci/host/pci-host-common.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c new file mode 100644 index 000000000000..e9f850f07968 --- /dev/null +++ b/drivers/pci/host/pci-host-common.c @@ -0,0 +1,194 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Copyright (C) 2014 ARM Limited + * + * Author: Will Deacon <will.deacon@arm.com> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_pci.h> +#include <linux/platform_device.h> + +#include "pci-host-common.h" + +static void gen_pci_release_of_pci_ranges(struct gen_pci *pci) +{ + pci_free_resource_list(&pci->resources); +} + +static int gen_pci_parse_request_of_pci_ranges(struct gen_pci *pci) +{ + int err, res_valid = 0; + struct device *dev = pci->host.dev.parent; + struct device_node *np = dev->of_node; + resource_size_t iobase; + struct resource_entry *win; + + err = of_pci_get_host_bridge_resources(np, 0, 0xff, &pci->resources, + &iobase); + if (err) + return err; + + resource_list_for_each_entry(win, &pci->resources) { + struct resource *parent, *res = win->res; + + switch (resource_type(res)) { + case IORESOURCE_IO: + parent = &ioport_resource; + err = pci_remap_iospace(res, iobase); + if (err) { + dev_warn(dev, "error %d: failed to map resource %pR\n", + err, res); + continue; + } + break; + case IORESOURCE_MEM: + parent = &iomem_resource; + res_valid |= !(res->flags & IORESOURCE_PREFETCH); + break; + case IORESOURCE_BUS: + pci->cfg.bus_range = res; + default: + continue; + } + + err = devm_request_resource(dev, parent, res); + if (err) + goto out_release_res; + } + + if (!res_valid) { + dev_err(dev, "non-prefetchable memory resource required\n"); + err = -EINVAL; + goto out_release_res; + } + + return 0; + +out_release_res: + gen_pci_release_of_pci_ranges(pci); + return err; +} + +static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci) +{ + int err; + u8 bus_max; + resource_size_t busn; + struct resource *bus_range; + struct device *dev = pci->host.dev.parent; + struct device_node *np = dev->of_node; + u32 sz = 1 << pci->cfg.ops->bus_shift; + + err = of_address_to_resource(np, 0, &pci->cfg.res); + if (err) { + dev_err(dev, "missing \"reg\" property\n"); + return err; + } + + /* Limit the bus-range to fit within reg */ + bus_max = pci->cfg.bus_range->start + + (resource_size(&pci->cfg.res) >> pci->cfg.ops->bus_shift) - 1; + pci->cfg.bus_range->end = min_t(resource_size_t, + pci->cfg.bus_range->end, bus_max); + + pci->cfg.win = devm_kcalloc(dev, resource_size(pci->cfg.bus_range), + sizeof(*pci->cfg.win), GFP_KERNEL); + if (!pci->cfg.win) + return -ENOMEM; + + /* Map our Configuration Space windows */ + if (!devm_request_mem_region(dev, pci->cfg.res.start, + resource_size(&pci->cfg.res), + "Configuration Space")) + return -ENOMEM; + + bus_range = pci->cfg.bus_range; + for (busn = bus_range->start; busn <= bus_range->end; ++busn) { + u32 idx = busn - bus_range->start; + + pci->cfg.win[idx] = devm_ioremap(dev, + pci->cfg.res.start + idx * sz, + sz); + if (!pci->cfg.win[idx]) + return -ENOMEM; + } + + return 0; +} + +int pci_host_common_probe(struct platform_device *pdev, + struct gen_pci *pci) +{ + int err; + const char *type; + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct pci_bus *bus, *child; + + type = of_get_property(np, "device_type", NULL); + if (!type || strcmp(type, "pci")) { + dev_err(dev, "invalid \"device_type\" %s\n", type); + return -EINVAL; + } + + of_pci_check_probe_only(); + + pci->host.dev.parent = dev; + INIT_LIST_HEAD(&pci->host.windows); + INIT_LIST_HEAD(&pci->resources); + + /* Parse our PCI ranges and request their resources */ + err = gen_pci_parse_request_of_pci_ranges(pci); + if (err) + return err; + + /* Parse and map our Configuration Space windows */ + err = gen_pci_parse_map_cfg_windows(pci); + if (err) { + gen_pci_release_of_pci_ranges(pci); + return err; + } + + /* Do not reassign resources if probe only */ + if (!pci_has_flag(PCI_PROBE_ONLY)) + pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS); + + + bus = pci_scan_root_bus(dev, pci->cfg.bus_range->start, + &pci->cfg.ops->ops, pci, &pci->resources); + if (!bus) { + dev_err(dev, "Scanning rootbus failed"); + return -ENODEV; + } + + pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); + + if (!pci_has_flag(PCI_PROBE_ONLY)) { + pci_bus_size_bridges(bus); + pci_bus_assign_resources(bus); + + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); + } + + pci_bus_add_devices(bus); + return 0; +} + +MODULE_DESCRIPTION("Generic PCI host driver common code"); +MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>"); +MODULE_LICENSE("GPL v2"); |