drm/xe: Detect pvc stepping
After checking multiple approach, I came to that proposal, that seems to best match reuse of XE work around infrastructure as this.
Wanted to have PVC also using the sub platform approach and after checking bspec for newer gen, I think we can agree that compute tile version ~= graphic version (or we can add compute_step in xe_step_info)
Tested on my setup:
[329956.250749] xe 0009:05:00.0: [drm:add_dr [drm]] ADD 00000000f571c240 kmalloc (13 bytes)
[329956.250887] xe 0009:05:00.0: [drm:xe_pci_probe [xe]] XE_PVC A0 0bd5:0003 dgfx:1 gfx100:1260 media100:1260 dma_m_s:52 tc:2
[329956.250971] xe 0009:05:00.0: [drm:xe_pci_probe [xe]] Stepping = (G:A0, M:**, D:**)
[329956.251131] xe 0009:05:00.0: [drm:add_dr [drm]] ADD 0000000044d8cf51 kmalloc (304 bytes)
@demarchi @mattrope @mbrost - highly interested by your feedback