[S] Change in coreboot[main]: ec/intel: read board ID one time from EC per stage

[Jérémy Compostella (Code Review)]

Attention is currently required from: Bora Guvendik, Cliff Huang, Jamie Ryu, Wonkyu Kim.

Jérémy Compostella has posted comments on this change by Wonkyu Kim. ( https://review.coreboot.org/c/coreboot/+/87247?usp=email )

Change subject: ec/intel: read board ID one time from EC per stage
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Patch Set 5:

(3 comments)

File src/ec/intel/board_id.c:

https://review.coreboot.org/c/coreboot/+/87247/comment/df15aca3_1f32ccd2?usp... :
PS5, Line 21: int get_rvp_board_id(void)
I am realizing that it has little flow. The goal is to avoid communication with EC each time the function is called. But if `send_ec_command()` fails, you will end up calling over and over.

I suggest setting `id` to `BOARD_ID_INIT` when `send_ec_command()` fails and adding the following at the beginning of the function:

if (id == BOARD_ID_INIT)
            return BOARD_ID_UNKNOWN;

https://review.coreboot.org/c/coreboot/+/87247/comment/813787ee_4df63601?usp... :
PS5, Line 25: Reading board id after first time reading
nit: Reading board **ID** after **the** first time reading

https://review.coreboot.org/c/coreboot/+/87247/comment/2002eaf7_ac97e318?usp... :
PS5, Line 29: Reading board id first time
Reading board **ID for the** first time