arm64: docs: Mandate that the I-cache doesn't hold stale kernel text

Although we require that the loaded kernel Image has been cleaned to the
PoC, we neglect to spell out the state of the I-cache. Although this
should be reasonably obvious, it doesn't hurt to be explicit.

Require that the I-cache doesn't hold any stale entries for the kernel
Image at boot.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200423093658.10602-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Will Deacon 2020-04-23 10:36:58 +01:00
parent 6a8b55ed40
commit e24e03aa00

View File

@ -173,7 +173,8 @@ Before jumping into the kernel, the following conditions must be met:
- Caches, MMUs
The MMU must be off.
Instruction cache may be on or off.
The instruction cache may be on or off, and must not hold any stale
entries corresponding to the loaded kernel image.
The address range corresponding to the loaded kernel image must be
cleaned to the PoC. In the presence of a system cache or other
coherent masters with caches enabled, this will typically require