diff --git a/sys/arm64/arm64/locore.S b/sys/arm64/arm64/locore.S --- a/sys/arm64/arm64/locore.S +++ b/sys/arm64/arm64/locore.S @@ -516,11 +516,10 @@ common: #if PAGE_SIZE != PAGE_SIZE_4K /* - * Create L3 pages. The kernel will be loaded at a 2M aligned - * address, however L2 blocks are too large when the page size is - * not 4k to map the kernel with such an aligned address. However, - * when the page size is larger than 4k, L2 blocks are too large to - * map the kernel with such an alignment. + * Create L3 and L3C pages. The kernel will be loaded at a 2M aligned + * address, enabling the creation of L3C pages. However, when the page + * size is larger than 4k, L2 blocks are too large to map the kernel + * with 2M alignment. */ #define PTE_SHIFT L3_SHIFT #define BUILD_PTE_FUNC build_l3_page_pagetable @@ -784,13 +783,17 @@ LEND(link_l2_pagetable) /* - * Builds count level 3 page table entries + * Builds count level 3 page table entries. Uses ATTR_CONTIGUOUS to create + * large page (L3C) mappings when the current VA and remaining count allow + * it. * x6 = L3 table * x7 = Block attributes * x8 = VA start * x9 = PA start (trashed) * x10 = Entry count (trashed) * x11, x12 and x13 are trashed + * + * VA start (x8) modulo L3C_SIZE must equal PA start (x9) modulo L3C_SIZE. */ LENTRY(build_l3_page_pagetable) /* @@ -811,8 +814,17 @@ /* Only use the output address bits */ lsr x9, x9, #L3_SHIFT + /* Check if an ATTR_CONTIGUOUS mapping is possible */ +1: tst x11, #(L3C_ENTRIES - 1) + b.ne 2f + cmp x10, #L3C_ENTRIES + b.lo 3f + orr x12, x12, #(ATTR_CONTIGUOUS) + b 2f +3: and x12, x12, #(~ATTR_CONTIGUOUS) + /* Set the physical address for this virtual address */ -1: orr x13, x12, x9, lsl #L3_SHIFT +2: orr x13, x12, x9, lsl #L3_SHIFT /* Store the entry */ str x13, [x6, x11, lsl #3]