Before commit 593669c2ac0f ("x86/PCI/ACPI: 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 ("x86/PCI/ACPI: 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 host bridge
resource list.
Then commit 63f1789ec716 ("x86/PCI/ACPI: Ignore resources consumed by
host bridge itself") ignores resources consumed by host bridge itself
by checking IORESOURCE_WINDOW flag, which accidently removed the
workaround for BIOS bug in 2) listed above.
It's really costed us much time to figure out this whole picture.
So we will refine interface acpi_dev_filter_resource_type as below,
which should be much 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 to work
around BIOS bugs, with comment to state it's workaround for BIOS bug.
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.
Sample ACPI table needing the workaround are archived at:
https://bugzilla.kernel.org/show_bug.cgi?id=94221
Fixes: 63f1789ec716("Ignore resources consumed by host bridge itself")
Reported-by: Bernhard Thaler <bernhard.thaler@xxxxxxxx>
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
Hi Bjorn and Rafael,
Great thanks to you two:) Now I think I have fully understand
the whole picture and the final code should be much easier for
understanding and maintenance.
Regards!
Gerry
---
arch/x86/pci/acpi.c | 5 ++---
drivers/acpi/resource.c | 38 ++++++++++++++++++++++++++++++++++----
2 files changed, 36 insertions(+), 7 deletions(-)
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index e4695985f9de..8c4b1201f340 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -337,7 +337,7 @@ static void probe_pci_root_info(struct pci_root_info *info,
info->bridge = device;
ret = acpi_dev_get_resources(device, list,
acpi_dev_filter_resource_type_cb,
- (void *)(IORESOURCE_IO | IORESOURCE_MEM));
+ (void *)(IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_WINDOW));
if (ret < 0)
dev_warn(&device->dev,
"failed to parse _CRS method, error code %d\n", ret);
@@ -346,8 +346,7 @@ 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..68b44eef67eb 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -567,6 +567,17 @@ int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
}
EXPORT_SYMBOL_GPL(acpi_dev_get_resources);
+static inline bool acpi_dev_match_producer_consumer(unsigned long types,
+ int producer)
+{
+ if ((types & IORESOURCE_WINDOW) && producer == ACPI_PRODUCER)
+ return true;
+ else if ((types & IORESOURCE_WINDOW) == 0 && producer == ACPI_CONSUMER)
+ return true;
+ else
+ return false;
+}
+
/**
* acpi_dev_filter_resource_type - Filter ACPI resource according to resource
* types
@@ -585,27 +596,46 @@ 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:
+ /*
+ * 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, reports
+ * resource provision by Memory32Fixed(). Please refer to:
+ * https://bugzilla.kernel.org/show_bug.cgi?id=94221
+ * So accept it no matter IORESOURCE_WINDOW is specified or not.
+ */
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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