[S] Change in coreboot[main]: soc/mediatek/mt8196: Add pwrsel driver

[Paul Menzel (Code Review)]

Attention is currently required from: Hung-Te Lin, Yidi Lin, Yu-Ping Wu.

Paul Menzel has posted comments on this change by Jarried Lin. ( https://review.coreboot.org/c/coreboot/+/85613?usp=email )

Change subject: soc/mediatek/mt8196: Add pwrsel driver
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Patch Set 1:

(4 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/85613/comment/58294621_1b975a8a?usp... :
PS1, Line 11: 
What values (profiles?) can be written by the firmware?

https://review.coreboot.org/c/coreboot/+/85613/comment/02033c6a_7e8534cc?usp... :
PS1, Line 14: PWR_SEL = 0x0
Aren’t two log messages added in the code?

File src/soc/mediatek/mt8196/mtk_pwrsel.c:

https://review.coreboot.org/c/coreboot/+/85613/comment/8dee263e_fa73ce78?usp... :
PS1, Line 22: 	printk(BIOS_INFO, "PWR_SEL = %#x\n",
It’d be great to have a comment documenting the possible values.

https://review.coreboot.org/c/coreboot/+/85613/comment/6ad59947_14e53b22?usp... :
PS1, Line 22: printk(BIOS_INFO, "PWR_SEL = %#x\n",
            : 	       read32p(MCUSYS_BASE + OFFSET_PWRSEL));
            : 	printk(BIOS_INFO, "PWRSEL_CONFIG = %#x\n",
            : 	       read32p(MFG_VCORE_AO_RPC_PWRSEL_CONFIG));
For an info level messages it’d be great to make this message user readable/understandable.