[coreboot-gerrit] [S] Change in coreboot[master]: mb/google/rex: Add devtree update support for variants

[Subrata Banik (Code Review)]

Attention is currently required from: Tarun Tuli, Kapil Porwal, Sumeet R Pawnikar, Eric Lai.

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74379 )

Change subject: mb/google/rex: Add devtree update support for variants
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Patch Set 3:

(1 comment)

File src/mainboard/google/rex/variants/rex0/ramstage.c:

https://review.coreboot.org/c/coreboot/+/74379/comment/f5a9767e_67c1f452 
PS2, Line 17: }
> I feel this above way of filling information is only applicable if we are sure that rex0 board won't have any other mchid i.e.CPU SKUs 
> What if we have rex0 board with different mchid for the same TDP i.e. different 15W CPU SKUs (PCI DID). For an example PCI_DID_INTEL_MTL_P_ID_5=0x7d16

sorry, i don't understand the reasoning why you think we won't be able to add different MCH ID if follow `.xxx = ` style of structure assignment ?

```
       struct cpu_power_limits limits[] = {
    	{
    		.mchid = PCI_DID_INTEL_MTL_P_ID_2,
    		.cpu_tdp = 15,
    		.pl1_min_power = 6000,
    		.pl1_max_power = 15000,
    		.pl2_min_power = 57000,
    		.pl2_max_power = 57000,
    		.pl4_power = 101000,
    	},
    	{
    		.mchid = PCI_DID_INTEL_MTL_P_ID_3,
    		.cpu_tdp = 15,
    		.pl1_min_power = 6000,
    		.pl1_max_power = 15000,
    		.pl2_min_power = 57000,
    		.pl2_max_power = 57000,
    		.pl4_power = 101000,
    	},
    	...
    	...
    	{
    		.mchid = PCI_DID_INTEL_MTL_P_ID_5,
    		.cpu_tdp = 15,
    		.pl1_min_power = 6000,
    		.pl1_max_power = 15000,
    		.pl2_min_power = 57000,
    		.pl2_max_power = 57000,
    		.pl4_power = 101000,
    	},
    };
```