[Bugfix v4] x86/PCI/ACPI: Fix regression caused by commit 63f1789ec716

From: Jiang Liu
Date: Tue Apr 07 2015 - 00:28:00 EST


Before commit 593669c2ac0f("Use common ACPI resource interfaces to
simplify implementation"), arch/x86/pci/acpi.c applies following
rules when parsing ACPI resources for PCI host bridge:
1) Ignore IO port resources defined by acpi_resource_io and
acpi_resource_fixed_io, which should be used to define resource
for PCI device instead of PCI bridge.
2) Accept IOMEM resource defined by acpi_resource_memory24,
acpi_resource_memory32 and acpi_resource_fixed_memory32.
These IOMEM resources are accepted to workaround some BIOS issue,
though they should be ignored. For example, PC Engines APU.1C
platform defines PCI host bridge IOMEM resources as:
Memory32Fixed (ReadOnly,
0x000A0000, // Address Base
0x00020000, // Address Length
)
Memory32Fixed (ReadOnly,
0x00000000, // Address Base
0x00000000, // Address Length
_Y00)
3) Accept all IO port and IOMEM resources defined by
acpi_resource_address{16,32,64,extended64}, no matter it's marked as
ACPI_CONSUMER or ACPI_PRODUCER.

Commit 593669c2ac0f("Use common ACPI resource interfaces to
simplify implementation") accept all IO port and IOMEM resources
defined by acpi_resource_io, acpi_resource_fixed_io,
acpi_resource_memory24, acpi_resource_memory32,
acpi_resource_fixed_memory32 and
acpi_resource_address{16,32,64,extended64}, which causes IO port
resources consumed by host bridge itself are listed in to host bridge
resource list.

Then commit 63f1789ec716("Ignore resources consumed by host bridge
itself") ignores resources consumed by host bridge itself by checking
IORESOURCE_WINDOW flag, which accidently removed the workaround in 2)
above for BIOS bug .

It's really costed us much time to figure out this whole picture.
So we refine interface acpi_dev_filter_resource_type as below,
which should be easier for maintence:
1) Caller specifies IORESOURCE_WINDOW flag to explicitly query resource
for bridge(PRODUCER), otherwise it's querying resource for
device(CONSUMER).
2) Ignore IO port resources defined by acpi_resource_io and
acpi_resource_fixed_io if IORESOURCE_WINDOW is specified.
3) Accpet IOMEM resource defined by acpi_resource_memory24,
acpi_resource_memory32 and acpi_resource_fixed_memory32 if both
IORESOURCE_WINDOW and IORESOURCE_MEM_8AND16BIT are specified to work
around BIOS issues.
4) Accept IO port and IOMEM defined by acpi_resource_addressxx if
a) IORESOURCE_WINDOW is specified and ACPI_PRODUCER is true
b) IORESOURCE_WINDOW is not specified and ACPI_PRODUCER is false

Currently acpi_dev_filter_resource_type() is only used by ACPI pci
host bridge and IOAPIC driver, so it shouldn't affect other drivers.

Another possible fix is to only ignore IO resource consumed by host
bridge and keep IOMEM resource consumed by host bridge, please refer to:
http://www.spinics.net/lists/linux-pci/msg39706.html

Sample ACPI table are archived at:
https://bugzilla.kernel.org/show_bug.cgi?id=94221

V3->V4:
1) Improve comments
2) Use flag IORESOURCE_MEM_8AND16BIT to work around BIOS issue

Fixes: 63f1789ec716("Ignore resources consumed by host bridge itself")
Reported-and-Tested-by: Bernhard Thaler <bernhard.thaler@xxxxxxxx>
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
arch/x86/pci/acpi.c | 8 +++++---
drivers/acpi/resource.c | 52 +++++++++++++++++++++++++++++++++++++++++------
2 files changed, 51 insertions(+), 9 deletions(-)

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index e4695985f9de..150774be0f3f 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -332,12 +332,15 @@ static void probe_pci_root_info(struct pci_root_info *info,
{
int ret;
struct resource_entry *entry, *tmp;
+ unsigned long res_flags;

sprintf(info->name, "PCI Bus %04x:%02x", domain, busnum);
info->bridge = device;
+ res_flags = IORESOURCE_IO | IORESOURCE_MEM |
+ IORESOURCE_WINDOW | IORESOURCE_MEM_8AND16BIT;
ret = acpi_dev_get_resources(device, list,
acpi_dev_filter_resource_type_cb,
- (void *)(IORESOURCE_IO | IORESOURCE_MEM));
+ (void *)res_flags);
if (ret < 0)
dev_warn(&device->dev,
"failed to parse _CRS method, error code %d\n", ret);
@@ -346,8 +349,7 @@ static void probe_pci_root_info(struct 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_WINDOW) == 0 ||
- (entry->res->flags & IORESOURCE_DISABLED))
+ if (entry->res->flags & IORESOURCE_DISABLED)
resource_list_destroy_entry(entry);
else
entry->res->name = info->name;
diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 5589a6e2a023..0187e0e11bb8 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -567,6 +567,12 @@ int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
}
EXPORT_SYMBOL_GPL(acpi_dev_get_resources);

+static bool acpi_dev_match_producer_consumer(unsigned long types, int producer)
+{
+ return ((types & IORESOURCE_WINDOW) && producer == ACPI_PRODUCER) ||
+ ((types & IORESOURCE_WINDOW) == 0 && producer == ACPI_CONSUMER);
+}
+
/**
* acpi_dev_filter_resource_type - Filter ACPI resource according to resource
* types
@@ -574,7 +580,19 @@ EXPORT_SYMBOL_GPL(acpi_dev_get_resources);
* @types: Valid resource types of IORESOURCE_XXX
*
* This is a hepler function to support acpi_dev_get_resources(), which filters
- * ACPI resource objects according to resource types.
+ * ACPI resource objects according to resource types and flags as below:
+ * 1) If flag IORESOURCE_WINDOW is not specified, it's querying resources
+ * consumed by device. That is to return:
+ * a) ACPI resources without producer_consumer flag
+ * b) ACPI resources with producer_consumer flag setting to CONSUMER.
+ * 2) If flag IORESOURCE_WINDOW is specified, it's querying resources provided
+ * by device. That is to return:
+ * a) ACPI resources with producer_consumer flag setting to PRODUCER.
+ * 3) But there's an exception. Some platforms, such as PC Engines APU.1C,
+ * report PCI host bridge resource provision by Memory32Fixed().
+ * Please refer to https://bugzilla.kernel.org/show_bug.cgi?id=94221
+ * So a special flag IORESOURCE_MEM_8AND16BIT is used to work around this
+ * BIOS issue.
*/
int acpi_dev_filter_resource_type(struct acpi_resource *ares,
unsigned long types)
@@ -585,27 +603,49 @@ int acpi_dev_filter_resource_type(struct acpi_resource *ares,
case ACPI_RESOURCE_TYPE_MEMORY24:
case ACPI_RESOURCE_TYPE_MEMORY32:
case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
- type = IORESOURCE_MEM;
+ /*
+ * These types of resource descriptor should be used to
+ * describe resource consumption instead of resource provision.
+ * But some platforms, such as PC Engines APU.1C, report
+ * resource provision by Memory32Fixed(). Please refer to:
+ * https://bugzilla.kernel.org/show_bug.cgi?id=94221
+ * So a special rule to work around BIOS issues.
+ */
+ if ((types & (IORESOURCE_WINDOW | IORESOURCE_MEM_8AND16BIT)) ==
+ (IORESOURCE_WINDOW | IORESOURCE_MEM_8AND16BIT) ||
+ acpi_dev_match_producer_consumer(types, ACPI_CONSUMER))
+ type = IORESOURCE_MEM;
break;
case ACPI_RESOURCE_TYPE_IO:
case ACPI_RESOURCE_TYPE_FIXED_IO:
- type = IORESOURCE_IO;
+ if (acpi_dev_match_producer_consumer(types, ACPI_CONSUMER))
+ type = IORESOURCE_IO;
break;
case ACPI_RESOURCE_TYPE_IRQ:
+ if (acpi_dev_match_producer_consumer(types, ACPI_CONSUMER))
+ type = IORESOURCE_IRQ;
+ break;
case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
- type = IORESOURCE_IRQ;
+ if (acpi_dev_match_producer_consumer(types,
+ ares->data.extended_irq.producer_consumer))
+ type = IORESOURCE_IRQ;
break;
case ACPI_RESOURCE_TYPE_DMA:
case ACPI_RESOURCE_TYPE_FIXED_DMA:
- type = IORESOURCE_DMA;
+ if (acpi_dev_match_producer_consumer(types, ACPI_CONSUMER))
+ type = IORESOURCE_DMA;
break;
case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
- type = IORESOURCE_REG;
+ if (acpi_dev_match_producer_consumer(types, ACPI_CONSUMER))
+ type = IORESOURCE_REG;
break;
case ACPI_RESOURCE_TYPE_ADDRESS16:
case ACPI_RESOURCE_TYPE_ADDRESS32:
case ACPI_RESOURCE_TYPE_ADDRESS64:
case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
+ if (!acpi_dev_match_producer_consumer(types,
+ ares->data.address.producer_consumer))
+ break;
if (ares->data.address.resource_type == ACPI_MEMORY_RANGE)
type = IORESOURCE_MEM;
else if (ares->data.address.resource_type == ACPI_IO_RANGE)
--
1.7.10.4

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