From: Jayachandran C jchandra@broadcom.com
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 unmap I/O resources with pci_unmap_iospace() when we release host bridge resources.
Signed-off-by: Jayachandran C jchandra@broadcom.com Signed-off-by: Sinan Kaya okaya@codeaurora.org [ Tomasz: merged in Sinan's patch to unmap IO resources properly, updated changelog] Signed-off-by: Tomasz Nowicki tn@semihalf.com Reviewed-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com --- drivers/acpi/pci_root.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index ae3fe4e..9a26dd1 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); + return; +err: + res->flags |= IORESOURCE_DISABLED; +} +#else +static inline 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);