[M] Change in coreboot[main]: cpu/x86/64bit: Install extended page tables in BSS

[Jérémy Compostella (Code Review)]

Attention is currently required from: Christian Walter, Johnny Lin, Jonathan Zhang, Patrick Rudolph, Shuo Liu, Tim Chu.

Jérémy Compostella has posted comments on this change by Patrick Rudolph. ( https://review.coreboot.org/c/coreboot/+/85806?usp=email )

Change subject: cpu/x86/64bit: Install extended page tables in BSS
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Patch Set 3:

(4 comments)

File src/cpu/x86/64bit/mmu.c:

https://review.coreboot.org/c/coreboot/+/85806/comment/6773cc75_93c50cab?usp... :
PS3, Line 12: #define _PRES (1ULL << 0)
Can't you use the BIT macro?

https://review.coreboot.org/c/coreboot/+/85806/comment/a5df0763_15d5152b?usp... :
PS3, Line 64: int
size_t

https://review.coreboot.org/c/coreboot/+/85806/comment/1bafc4aa_8da36ea0?usp... :
PS3, Line 59: if (cpu_supports_1gb_hugepage()) {
            : 		const uintptr_t max_addr = 1ULL * GiB * 512ULL * 512ULL;
            : 		const uint64_t incr = 1ULL * GiB;
            : 
            : 		/* Build P4MLE */
            : 		for (int i = 0; i < 512; i++)
            : 			p4mle[i] = _GEN_DIR(&pdpt[i * 512]);
            : 
            : 		/* Build PDPT */
            : 		uint64_t *page_table_ptr = pdpt;
            : 		for (uintptr_t addr = 0; addr < max_addr; addr += incr, page_table_ptr++)
            : 			*page_table_ptr = _GEN_PAGE(addr);
            : 	} else {
            : 		const uintptr_t max_addr = 2ULL * MiB * 512ULL * 512ULL;
            : 		const uint64_t incr = 2ULL * MiB;
            : 
            : 		/* Build P4MLE */
            : 		p4mle[0] = _GEN_DIR(&pdpt[0]);
            : 
            : 		/* Build PDPT */
            : 		for (int i = 0; i < 512; i++)
            : 			pdpt[i] = _GEN_DIR(&pdt[i * 512]);
            : 
            : 		/* Build PDT */
            : 		uint64_t *page_table_ptr = pdt;
            : 		for (uintptr_t addr = 0; addr < max_addr; addr += incr, page_table_ptr++)
            : 			*page_table_ptr = _GEN_PAGE(addr);
            : 	}
            : 
There are a lot in common between these two branches, isn't it a way to share more code ?

https://review.coreboot.org/c/coreboot/+/85806/comment/60ed878c_1b7db564?usp... :
PS3, Line 150: 	else
unnecessary `else` keyword.