soc/amd/common/block/psp/psp_gen2: use SMN access to PSP

Since we can't rely on the MMIO base address in the PSP_ADDR_MSR MSR to
access the PSP mailbox registers, switch to using the SMN mapping of the
PSP mailbox registers. The PSP SMN base address is taken from the amdgpu
driver in the Linux kernel.

BUG=b:229779018
TEST=Mandolin still boots successfully and there are no errors/warnings
about possibly PSP-related things.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I9d17e523e9ae8d8e14ecedc37131a81f82351487
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64034
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions