[XL] Change in coreboot[main]: soc/mediatek/mt8196: Add RTC driver

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Jarried Lin, Paul Menzel, Yidi Lin.

Yu-Ping Wu has posted comments on this change by Jarried Lin. ( https://review.coreboot.org/c/coreboot/+/85978?usp=email )

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

(9 comments)

Patchset:

PS1: 
Partial review. src/soc/mediatek/mt8196/mt6685_rtc.c is not reviewed yet.

Commit Message:

https://review.coreboot.org/c/coreboot/+/85978/comment/c8c97fd7_f06354c1?usp... :
PS1, Line 9: rtc
RTC

File src/soc/mediatek/common/include/soc/rtc_common.h:

https://review.coreboot.org/c/coreboot/+/85978/comment/1b6ed322_2db3abb1?usp... :
PS1, Line 107: /* The return result of the clock calibration
             :  * The result is relationship coefficient between 26M and 32K,
             :  * which is non-unit.
             :  */
Okay, I think this explains nothing. If the return value is NOT a unit, let's remove this comment (and remove the blank line above).

File src/soc/mediatek/common/rtc_osc_init.c:

https://review.coreboot.org/c/coreboot/+/85978/comment/45087dce_6dfaca48?usp... :
PS1, Line 7: u16
> Why limit the length?

Because the data width for rtc_read/rtc_write API is u16.

File src/soc/mediatek/mt8196/include/soc/mt6685_rtc_hw.h:

https://review.coreboot.org/c/coreboot/+/85978/comment/62237abf_d3792be8?usp... :
PS1, Line 24:  
Remove this extra space. Same for other values below.

https://review.coreboot.org/c/coreboot/+/85978/comment/ef6b5e9c_a3936cab?usp... :
PS1, Line 89: mask
masks

File src/soc/mediatek/mt8196/include/soc/rtc.h:

https://review.coreboot.org/c/coreboot/+/85978/comment/40e3cf96_1ec03b60?usp... :
PS1, Line 58: WATCH_INIT_EXPIRED_TIME
Can we have a more descriptive name? `XXX_US`

https://review.coreboot.org/c/coreboot/+/85978/comment/e4f94527_7eb065a7?usp... :
PS1, Line 59: WAIT_TIME_US
Same here. Wait for what?

Also change these two to enum for consistency.

File src/soc/mediatek/mt8196/mt6685_rtc.c:

https://review.coreboot.org/c/coreboot/+/85978/comment/c2e0d743_9748dc5e?usp... :
PS1, Line 43: freq
Can we name these 3 fields instead of using an array?