[coreboot-gerrit] [S] Change in coreboot[main]: soc/intel/cmn/pmc: Add support for early power off

[Jérémy Compostella (Code Review)]

Attention is currently required from: Intel coreboot Reviewers, Julius Werner, Karthik Ramasubramanian, Subrata Banik.

Jérémy Compostella has posted comments on this change by Subrata Banik. ( https://review.coreboot.org/c/coreboot/+/86336?usp=email )

Change subject: soc/intel/cmn/pmc: Add support for early power off
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Patch Set 3:

(1 comment)

File src/soc/intel/common/block/pmc/pmclib.c:

https://review.coreboot.org/c/coreboot/+/86336/comment/21c234e0_b1965b7b?usp... :
PS3, Line 635: __weak void platform_do_early_poweroff(void)
I propose two enhancements as follows:

1. The implementation of the subordinate function should be placed within the `src/ec/google/chromeec/ec.c` file, encapsulated by an appropriate Kconfig conditional compilation block.

2. The default function can be defined using the following code snippet:

```c
__weak void platform_do_early_poweroff(void)
{
    printk(BIOS_EMERG, "Early power off is not supported on this platform. "
           "Proceeding with the standard PMC shutdown procedure.\n");

pmc_control_poweroff();
}
```

The `platform_do_early_poweroff` function serves as a generic fallback that issues an emergency print statement and invokes the `pmc_control_poweroff` function to initiate a power-off sequence.