[PATCH V8 4/9] acpi, pci: Support IO resources when parsing PCI host bridge resources.
From: Lorenzo Pieralisi <hidden>
Date: 2016-06-02 17:29:43
Also in:
linux-acpi, linux-pci, lkml
On Mon, May 30, 2016 at 05:14:17PM +0200, Tomasz Nowicki wrote:
Platforms that have memory mapped IO port (such as ARM64) need special handling for PCI I/O resources. For host bridge's resource probing case these resources need to be fixed up with pci_register_io_range/pci_remap_iospace etc. The same I/O resources need to be released after hotplug removal so that it can be re-added back by the pci_remap_iospace function during insertion. As a consequence we unmap I/O resources with pci_unmap_iospace when we release host bridge resources. Signed-off-by: Jayachandran C <redacted> Signed-off-by: Sinan Kaya <redacted> Signed-off-by: Tomasz Nowicki <redacted> --- drivers/acpi/pci_root.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)
I will take a rain-check on ACPI PCI IO space consolidation between IA64 and ARM64.
quoted hunk ↗ jump to hunk
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index ae3fe4e..ee3b728 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c@@ -720,6 +720,40 @@ next: } } +#ifdef PCI_IOBASE +static void acpi_pci_root_remap_iospace(struct resource_entry *entry) +{ + struct resource *res = entry->res; + resource_size_t cpu_addr = res->start; + resource_size_t pci_addr = cpu_addr - entry->offset; + resource_size_t length = resource_size(res); + unsigned long port; + + if (pci_register_io_range(cpu_addr, length)) + goto err; + + port = pci_address_to_pio(cpu_addr); + if (port == (unsigned long)-1) + goto err; + + res->start = port; + res->end = port + length - 1; + entry->offset = port - pci_addr; + + if (pci_remap_iospace(res, cpu_addr) < 0) + goto err; + + pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
Side note: we need to allocate and request a resource for the corresponding memory resource (and do that for DT and ACPI alike), see above. Reviewed-by: Lorenzo Pieralisi <redacted>
quoted hunk ↗ jump to hunk
+ return; +err: + res->flags |= IORESOURCE_DISABLED; +} +#else +static void acpi_pci_root_remap_iospace(struct resource_entry *entry) +{ +} +#endif + int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info) { int ret;@@ -740,6 +774,9 @@ int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info) "no IO and memory resources present in _CRS\n"); else { resource_list_for_each_entry_safe(entry, tmp, list) { + if (entry->res->flags & IORESOURCE_IO) + acpi_pci_root_remap_iospace(entry); + if (entry->res->flags & IORESOURCE_DISABLED) resource_list_destroy_entry(entry); else@@ -811,6 +848,8 @@ static void acpi_pci_root_release_info(struct pci_host_bridge *bridge) resource_list_for_each_entry(entry, &bridge->windows) { res = entry->res; + if (res->flags & IORESOURCE_IO) + pci_unmap_iospace(res); if (res->parent && (res->flags & (IORESOURCE_MEM | IORESOURCE_IO))) release_resource(res);-- 1.9.1