[XL] Change in coreboot[main]: soc/intel/ptl: Do initial Panther Lake SoC commit till bootblock

[Saurabh Mishra (Code Review)]

Attention is currently required from: Ashish Kumar Mishra, Dinesh Gehlot, Eran Mitrani, Felix Singer, Jakub Czapiga, Jérémy Compostella, Kapil Porwal, Subrata Banik, Tarun.

Saurabh Mishra has posted comments on this change by Saurabh Mishra. ( https://review.coreboot.org/c/coreboot/+/83354?usp=email )

Change subject: soc/intel/ptl: Do initial Panther Lake SoC commit till bootblock
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Patch Set 31:

(1 comment)

File src/soc/intel/pantherlake/Kconfig:

https://review.coreboot.org/c/coreboot/+/83354/comment/3663416d_45997d07?usp... :
PS14, Line 67: ~1KiB)
> Sure, let me cross confirm with FSP Team.

Hi Subrata, i have checked with FSP Team, as per the MTL FSP Integration guide, the FSP Stack and Heap requirement for CAR is given below:

MTL: FSP's stack usage starts from the current stack pointer. The minimum stack size requirement for FSP-M
  is 256KB.
  The boot loader must provide at minimum 256KB of stack and 128KB of HOB heap to execute
     FSP on this platform.

The external released FSP Integration guide for MTL should also contains the same information.

For PTL, as per PTL FSP Integration guide, the boot loader must provide at minimum 256KB of stack and 160KB of HOB heap to execute FSP on this platform.   
PTL:
Below are the heap and stack requirements for FSP on this platform:

HOB Heap requirement:
  HOB Heap | UPD                           | Setting
  ---------|-------------------------------|----------------------------------------------------
  Base     |FSPM_UPD.FspmArchUpd.StackBase |Any non-conflict CAR region (0xFEF17F00 as default)
  Size     |FSPM_UPD.FspmArchUpd.StackSize |at least 128KB

Stack requirement:
  FSP's stack usage starts from the current stack pointer. The minimum stack size requirement for FSP-M
  is 256KB.