[XS] Change in coreboot[main]: mb/intel/mtlrvp: add 512KB SI_EC FMAP region

[Subrata Banik (Code Review)]

Subrata Banik has submitted this change. ( https://review.coreboot.org/c/coreboot/+/79209?usp=email )

Change subject: mb/intel/mtlrvp: add 512KB SI_EC FMAP region
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mb/intel/mtlrvp: add 512KB SI_EC FMAP region

This patch introduces the 512KB SI_EC FMAP region for storing the EC
firmware, a necessary addition to support EC chips without internal
flash memory.

As a testing platform, the MTLRVP Chrome SKU is utilized in conjunction
with the Microchip EC1723, and the changes are verified.

Cq-Depend: chrome-internal:6691498
Cq-Depend: chrome-internal:6741356
BUG=b:289783489
TEST=build "emerge-rex coreboot chromeos-bootimage" is successful.
changes are verified.
EC Log:
23-11-06 17:46:49.564 --- UART initialized after reboot ---
23-11-06 17:46:49.564 [Image: RO, mtlrvpp_m1723_v3.5.142816-ec:6596a3,
os:f660f7,cmsis:42cf18,picolibc:6669e4]
23-11-06 17:46:54.609 D: Power state: S5 --> S5S4
23-11-06 17:46:54.620 D: Power state: S5S4 --> S4
23-11-06 17:46:54.620 D: Power state: S4 --> S4S3
23-11-06 17:46:54.642 I: power state 10 = S3S0, in 0x0087
23-11-06 17:46:54.642 ec:~>: Power state: S3S0 --> S0

Change-Id: I788dbeaad05e5d6904fb2c7c681a0bf653dc7d84
Signed-off-by: Deepti Deshatty 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79209
Reviewed-by: Eric Lai 
Reviewed-by: Subrata Banik 
Reviewed-by: Vijay P Hiremath 
Tested-by: build bot (Jenkins) 
---
M src/mainboard/intel/mtlrvp/chromeos.fmd
1 file changed, 1 insertion(+), 0 deletions(-)

Approvals:
  Subrata Banik: Looks good to me, approved
  build bot (Jenkins): Verified
  Vijay P Hiremath: Looks good to me, but someone else must approve
  Eric Lai: Looks good to me, approved

diff --git a/src/mainboard/intel/mtlrvp/chromeos.fmd b/src/mainboard/intel/mtlrvp/chromeos.fmd
index c32a9f0..92e17e6 100644
--- a/src/mainboard/intel/mtlrvp/chromeos.fmd
+++ b/src/mainboard/intel/mtlrvp/chromeos.fmd
@@ -1,6 +1,7 @@
 FLASH 32M {
    SI_ALL 9M {
    	SI_DESC 16K
+		SI_EC 512K
    	SI_ME
    }
    SI_BIOS 23M {