Messages in this thread | | | Subject | Re: [Patch v7 4/7] PCI/ACPI: Add interface acpi_pci_root_create() | From | Tomasz Nowicki <> | Date | Thu, 5 Nov 2015 15:21:34 +0100 |
| |
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@arm.com> > Tested-by: Tony Luck <tony.luck@intel.com> > Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> > Signed-off-by: Liu Jiang <jiang.liu@linux.intel.com> > --- > 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?
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?
Thanks, Tomasz
| |