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ArmPkg/ArmMmuLib: Add new attribute WRITE_BACK_NONSHAREABLE

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Flash region needs to be set as cacheable (write back) to increase
performance, if PEI is still XIP on flash or DXE FV is decompressed
from flash FV. However some ARM platforms do not support to set flash
as inner shareable since flash is not normal DDR memory and it will
not respond to cache snoop request, which will causes system hang
after MMU is enabled.

So we need a new ARM memory region attribute WRITE_BACK_NONSHAREABLE
for flash region on these platforms specifically. This attribute will
set the region as write back but not inner shared.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Peicong Li <lipeicong@huawei.com>
Signed-off-by: Heyi Guo <heyi.guo@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
This commit is contained in:
Peicong Li
2017-11-07 20:56:51 +08:00
committed by Ard Biesheuvel
parent 050763db07
commit 829633e3a8
2 changed files with 12 additions and 0 deletions
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8
ArmPkg/Include/Library/ArmLib.h
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@@ -41,6 +41,14 @@ typedef enum {
ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_UNCACHED_UNBUFFERED,
ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK,
ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK,
// On some platforms, memory mapped flash region is designed as not supporting
// shareable attribute, so WRITE_BACK_NONSHAREABLE is added for such special
// need.
// Do NOT use below two attributes if you are not sure.
ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK_NONSHAREABLE,
ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_BACK_NONSHAREABLE,
ARM_MEMORY_REGION_ATTRIBUTE_WRITE_THROUGH,
ARM_MEMORY_REGION_ATTRIBUTE_NONSECURE_WRITE_THROUGH,
ARM_MEMORY_REGION_ATTRIBUTE_DEVICE,