On 2015/11/5 22:21, Tomasz Nowicki wrote: > On 14.10.2015 08:29, Jiang Liu wrote: >> Introduce common interface acpi_pci_root_create() and related data >> structures to create PCI root bus for ACPI PCI host bridges. It will >> be used to kill duplicated arch specific code for IA64 and x86. It may >> also help ARM64 in future. >> >> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> >> Tested-by: Tony Luck <tony.luck@xxxxxxxxx> >> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> >> Signed-off-by: Liu Jiang <jiang.liu@xxxxxxxxxxxxxxx> >> --- >> drivers/acpi/pci_root.c | 204 >> ++++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/pci-acpi.h | 24 ++++++ >> 2 files changed, 228 insertions(+) >> >> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c >> index 393706a5261b..850d7bf0c873 100644 >> --- a/drivers/acpi/pci_root.c >> +++ b/drivers/acpi/pci_root.c >> @@ -652,6 +652,210 @@ static void acpi_pci_root_remove(struct >> acpi_device *device) >> kfree(root); >> } >> >> +/* >> + * Following code to support acpi_pci_root_create() is copied from >> + * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64 >> + * and ARM64. >> + */ >> +static void acpi_pci_root_validate_resources(struct device *dev, >> + struct list_head *resources, >> + unsigned long type) >> +{ >> + LIST_HEAD(list); >> + struct resource *res1, *res2, *root = NULL; >> + struct resource_entry *tmp, *entry, *entry2; >> + >> + BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0); >> + root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource; >> + >> + list_splice_init(resources, &list); >> + resource_list_for_each_entry_safe(entry, tmp, &list) { >> + bool free = false; >> + resource_size_t end; >> + >> + res1 = entry->res; >> + if (!(res1->flags & type)) >> + goto next; >> + >> + /* Exclude non-addressable range or non-addressable portion */ >> + end = min(res1->end, root->end); >> + if (end <= res1->start) { >> + dev_info(dev, "host bridge window %pR (ignored, not CPU >> addressable)\n", >> + res1); >> + free = true; >> + goto next; >> + } else if (res1->end != end) { >> + dev_info(dev, "host bridge window %pR ([%#llx-%#llx] >> ignored, not CPU addressable)\n", >> + res1, (unsigned long long)end + 1, >> + (unsigned long long)res1->end); >> + res1->end = end; >> + } >> + >> + resource_list_for_each_entry(entry2, resources) { >> + res2 = entry2->res; >> + if (!(res2->flags & type)) >> + continue; >> + >> + /* >> + * I don't like throwing away windows because then >> + * our resources no longer match the ACPI _CRS, but >> + * the kernel resource tree doesn't allow overlaps. >> + */ >> + if (resource_overlaps(res1, res2)) { >> + res2->start = min(res1->start, res2->start); >> + res2->end = max(res1->end, res2->end); >> + dev_info(dev, "host bridge window expanded to %pR; >> %pR ignored\n", >> + res2, res1); >> + free = true; >> + goto next; >> + } >> + } >> + >> +next: >> + resource_list_del(entry); >> + if (free) >> + resource_list_free_entry(entry); >> + else >> + resource_list_add_tail(entry, resources); >> + } >> +} >> + >> +int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info) >> +{ >> + int ret; >> + struct list_head *list = &info->resources; >> + struct acpi_device *device = info->bridge; >> + struct resource_entry *entry, *tmp; >> + unsigned long flags; >> + >> + flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT; >> + ret = acpi_dev_get_resources(device, list, >> + acpi_dev_filter_resource_type_cb, >> + (void *)flags); >> + if (ret < 0) >> + dev_warn(&device->dev, >> + "failed to parse _CRS method, error code %d\n", ret); >> + else if (ret == 0) >> + dev_dbg(&device->dev, >> + "no IO and memory resources present in _CRS\n"); >> + else { >> + resource_list_for_each_entry_safe(entry, tmp, list) { >> + if (entry->res->flags & IORESOURCE_DISABLED) >> + resource_list_destroy_entry(entry); >> + else >> + entry->res->name = info->name; >> + } >> + acpi_pci_root_validate_resources(&device->dev, list, >> + IORESOURCE_MEM); >> + acpi_pci_root_validate_resources(&device->dev, list, >> + IORESOURCE_IO); > > It is not clear to me why we need these two calls above ^^^. We are > using pci_acpi_root_add_resources(info) later. Is it not enough? Hi Tomasz, acpi_pci_root_validate_resources() will try adjust (or fix) conflicting resources among all resources of the PCI host bridge, but pci_acpi_root_add_resources() only rejects conflicting resources. > > Also, I cannot use acpi_pci_probe_root_resources() in my ARM64 PCI > driver. It is because acpi_dev_get_resources is adding > translation_offset to IO ranges start address and then: > acpi_pci_root_validate_resources(&device->dev, list, > IORESOURCE_IO); > rejects that IO regions as it is out of my 0x0-SZ_16M window. > > Does acpi_pci_probe_root_resources meant to be x86 specific and I should > avoid using it? It should be generic, but we have some issue in support of translation_offset. I'm trying to get this fixed. Thanks, Gerry > > Thanks, > Tomasz -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html