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soc/intel/common: Ignore prefetch PCI attribute for IGD BAR0 

From Meteorlake, IGD BAR0(GTTMMADR) is changed to 64bit prefetchable.
Due to the prefetchable attribute, resource allocation for IGD BAR0 is
assigned WC memory and it causes kernel driver failure.

For avoiding kernel driver failure, ignore prefetch PCI attribute
for IGD BAR0 to assign UC memory.

We're working on publishing below information.
- IGD BAR0(GTTMMADR) is changed to 64bit prefetchable BAR
- GTTMMADDR BAR should be always mapped as UC memory although
  marked Pre-fetchable.

BUG=b:241746156
TEST=boot to OS and check guc driver loading successful
Signed-off-by: Wonkyu Kim <wonkyu.kim@intel.com>
Change-Id: I76d816d51f32f99c5ebcca54f13ec6d4ba77bba5
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66403
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Tarun Tuli <taruntuli@google.com>
This commit is contained in:
Wonkyu Kim 2022-08-03 12:47:06 -07:00 committed by Subrata Banik
parent 9969f4b609
commit 91bd6e19c9
2 changed files with 19 additions and 1 deletions
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7
src/soc/intel/common/block/graphics/Kconfig
View File

@ -29,4 +29,11 @@ config SOC_INTEL_GFX_FRAMEBUFFER_OFFSET
with GTT_SIZE value. On SoC platform where PCI config offset 0x18 points
to the GMADR directly can use the default value 0x0 without any override.
config SOC_INTEL_GFX_NON_PREFETCHABLE_MMIO
bool
default n
help
Ignore BAR0(offset 0x10)'s pre-fetchable attribute to use non-prefetchable
MMIO to fix OS display driver failure.
endif

13
src/soc/intel/common/block/graphics/graphics.c
View File

@ -164,8 +164,19 @@ void graphics_gtt_rmw(unsigned long reg, uint32_t andmask, uint32_t ormask)
graphics_gtt_write(reg, val);
}
static void graphics_dev_read_resources(struct device *dev)
{
pci_dev_read_resources(dev);
if (CONFIG(SOC_INTEL_GFX_NON_PREFETCHABLE_MMIO)) {
struct resource *res_bar0 = find_resource(dev, PCI_BASE_ADDRESS_0);
if (res_bar0->flags & IORESOURCE_PREFETCH)
res_bar0->flags &= ~IORESOURCE_PREFETCH;
}
}
static const struct device_operations graphics_ops = {
.read_resources = pci_dev_read_resources,
.read_resources = graphics_dev_read_resources,
.set_resources = pci_dev_set_resources,
.enable_resources = pci_dev_enable_resources,
.init = gma_init,