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| author | Jiang Liu <jiang.liu@linux.intel.com> | 2015-04-30 07:41:28 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-04-30 23:17:34 +0300 |
| commit | 2c62e8492ed7358bbe7da51666c7e0f6da9474ee (patch) | |
| tree | 2365277b20cc65a81df81fc6ad56187662d44f81 /drivers/acpi | |
| parent | b787f68c36d49bb1d9236f403813641efa74a031 (diff) | |
| download | linux-2c62e8492ed7358bbe7da51666c7e0f6da9474ee.tar.xz | |
x86/PCI/ACPI: Make all resources except [io 0xcf8-0xcff] available on PCI bus
An IO port or MMIO resource assigned to a PCI host bridge may be
consumed by the host bridge itself or available to its child
bus/devices. The ACPI specification defines a bit (Producer/Consumer)
to tell whether the resource is consumed by the host bridge itself,
but firmware hasn't used that bit consistently, so we can't rely on it.
Before commit 593669c2ac0f ("x86/PCI/ACPI: Use common ACPI resource
interfaces to simplify implementation"), arch/x86/pci/acpi.c ignored
all IO port resources defined by acpi_resource_io and
acpi_resource_fixed_io to filter out IO ports consumed by the host
bridge itself.
Commit 593669c2ac0f ("x86/PCI/ACPI: Use common ACPI resource interfaces
to simplify implementation") started accepting all IO port and MMIO
resources, which caused a regression that IO port resources consumed
by the host bridge itself became available to its child devices.
Then commit 63f1789ec716 ("x86/PCI/ACPI: Ignore resources consumed by
host bridge itself") ignored resources consumed by the host bridge
itself by checking the IORESOURCE_WINDOW flag, which accidently removed
MMIO resources defined by acpi_resource_memory24, acpi_resource_memory32
and acpi_resource_fixed_memory32.
On x86 and IA64 platforms, all IO port and MMIO resources are assumed
to be available to child bus/devices except one special case:
IO port [0xCF8-0xCFF] is consumed by the host bridge itself
to access PCI configuration space.
So explicitly filter out PCI CFG IO ports[0xCF8-0xCFF]. This solution
will also ease the way to consolidate ACPI PCI host bridge common code
from x86, ia64 and ARM64.
Related ACPI table are archived at:
https://bugzilla.kernel.org/show_bug.cgi?id=94221
Related discussions at:
http://patchwork.ozlabs.org/patch/461633/
https://lkml.org/lkml/2015/3/29/304
Fixes: 63f1789ec716 (Ignore resources consumed by host bridge itself)
Reported-by: Bernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: 4.0+ <stable@vger.kernel.org> # 4.0+
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/resource.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c index 5589a6e2a023..8244f013f210 100644 --- a/drivers/acpi/resource.c +++ b/drivers/acpi/resource.c @@ -573,7 +573,7 @@ EXPORT_SYMBOL_GPL(acpi_dev_get_resources); * @ares: Input ACPI resource object. * @types: Valid resource types of IORESOURCE_XXX * - * This is a hepler function to support acpi_dev_get_resources(), which filters + * This is a helper function to support acpi_dev_get_resources(), which filters * ACPI resource objects according to resource types. */ int acpi_dev_filter_resource_type(struct acpi_resource *ares, |