Change in coreboot[master]: [WIP] src/drivers/intel/fsp2_0: Add FSP 2.3 support

[Subrata Banik (Code Review)]

Attention is currently required from: Anil Kumar K, Paul Menzel, Andrey Petrov, Patrick Rudolph.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59324 )

Change subject: [WIP] src/drivers/intel/fsp2_0: Add FSP 2.3 support
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Patch Set 11:

(5 comments)

Patchset:

PS11:
> Sure. here are the details. I have added these in Kconfig as well […]

@Paul, can you please access https://cdrdv2.intel.com/v1/dl/getContent/644852?explicitVersion=true&wa... (FSP 2.3 spec and page 7 has the delta over FSP 2.2)

File src/drivers/intel/fsp2_0/hand_off_block.c:

https://review.coreboot.org/c/coreboot/+/59324/comment/96f82ccb_3edada60 
PS3, Line 24: 
            : #ifdef CONFIG_PLATFORM_USES_FSP2_3
you don't need this guard

make fsp_nv_storage_guid_2 no harm

https://review.coreboot.org/c/coreboot/+/59324/comment/9fdb79aa_7f1912b6 
PS3, Line 318: 	return fsp_find_extension_hob_by_guid(fsp_nv_storage_guid, size);
const uint8_t fsp_nv_storage_guid_2[16] = {
    0x8f, 0x78, 0x66, 0x48, 0xa8, 0x6b, 0xd8, 0x47,
    0x83, 0x6, 0xac, 0xf7, 0x7f, 0x55, 0x10, 0x46
};

const void *fsp_find_nv_storage_data(size_t *size)
{
    if (CONFIG(PLATFORM_USES_FSP2_3))
    	return fsp_find_extension_hob_by_guid(fsp_nv_storage_guid_2, size);

return fsp_find_extension_hob_by_guid(fsp_nv_storage_guid, size);
}

File src/drivers/intel/fsp2_0/header_display.c:

https://review.coreboot.org/c/coreboot/+/59324/comment/37b8b1bf_453b3c45 
PS3, Line 10: ext_revision.val = 0;
you don't need this

https://review.coreboot.org/c/coreboot/+/59324/comment/3a866356_8853d6fa 
PS3, Line 14: 6
worthwhile to make use of a macro for this ?

or

why not like this, because typically all FSP versions are backward compatible so, FSP2.4 should select PLATFORM_USES_FSP2_3 that way this `if` clause will be always true for FSP2.3 onward platform. isn't it ?

if (CONFIG(PLATFORM_USES_FSP2_3))
    ext_revision.val = hdr->extended_fsp_revision;