- If Smepmp is enabled, the access flags of an entry are determined based on
truth table defined in Smepmp.
- First PMP entry (index 0) is reserved.
- Existing boot PMP entries start from index 1.
- Since enabling Smepmp revokes the access privileges of the M-mode software
on S/U-mode region, first PMP entry is used to map/unmap the shared memory
between M and S/U-mode. This allows a temporary access window for the M-mode
software to read/write to S/U-mode memory region.
Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
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