[coreboot-gerrit] Change in coreboot[master]: drivers/intel/fsp2_0: Add support for MP PPI services2 APIs

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Furquan Shaikh, Martin Roth, Subrata Banik, Meera Ravindranath, Aamir Bohra, Tim Wawrzynczak, Andrey Petrov, Patrick Rudolph.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49474 )

Change subject: drivers/intel/fsp2_0: Add support for MP PPI services2 APIs
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Patch Set 4:

(1 comment)

Patchset:

PS4: 
Aamir, I think I have some ideas here, let me know what you think.

It looks like the difference between MPServices 1 & 2 is:
1) A new callback StartupAllCPUs
2) Change from EFI_PEI_MP_SERVICES_PPI to EDKII_PEI_MP_SERVICES2_PPI
3) Dropped the EFI_PEI_SERVICES** parameter from all of the callbacks

Therefore, the underlying implementations of each callback, from coreboot's POV, is identical.

So, I propose to change the driver to look more like the following:

Keep just one mp_service_ppi.c file, but instead of directly installing each function, organize like the following:

```
static efi_return_status_t mp_get_number_of_processors(
             efi_uintn_t *number_of_processors, efi_uintn_t *number_of_enabled_processors)
{
      	if (number_of_processors == NULL || number_of_enabled_processors ==
    		NULL)
    	return FSP_INVALID_PARAMETER;

*number_of_processors = get_cpu_count();
    *number_of_enabled_processors = get_cpu_count();
}
efi_return_status_t mps2_get_number_of_processors(
    efi_pei_mp_services_ppi *ignored1,
    efi_uintn_t *number_of_processors,
    efi_uintn_t *number_of_enabled_processors)
{
     return mp_get_number_of_processors(number_of_processors, number_of_enabled_processors);
}

efi_return_status_t mps1_get_number_of_processors(const
    efi_pei_services **ignored1, efi_pei_mp_services_ppi *ignored2,
    efi_uintn_t *number_of_processors,
    efi_uintn_t *number_of_enabled_processors)
{
    return mp_get_number_of_processors(number_of_processors, number_of_enabled_processors);
}

/* similarly for each callback that is shared... */

```

then add prototypes for the mps1_ and mps2_ functions to a local header file,
and add an mps1.c and mps2.c (or similar) which have the appropriate
```
static efi_pei_mp_services_ppi mp_service_ppi = {
...
};

efi_pei_mp_services_ppi *mp_fill_ppi_services_data(void)
{
      return mp_service_ppi;
}
```

section for each type.

WDYT Aamir?