arch/x86/include/smm_call: improve documentation of call_smm

Since the inline assembly code in call_smm doesn't make it exactly
obvious how this function to call the APMC SMI handler works in detail,
add a more detailed explanation as comment.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I3566af191492ce00a3033335ff80e01c33e98e63
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79834
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@amd.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions