x86: map UV chipset space - pagetable
Add boot-time function for creating additional 2MB page table entries for
mapping chipset specific cached/uncached ranges.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 77d129d..57d5eff 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -202,6 +202,46 @@
}
/*
+ * Create large page table mappings for a range of physical addresses.
+ */
+static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
+ pgprot_t prot)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
+ for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
+ pgd = pgd_offset_k((unsigned long)__va(phys));
+ if (pgd_none(*pgd)) {
+ pud = (pud_t *) spp_getpage();
+ set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ pud = pud_offset(pgd, (unsigned long)__va(phys));
+ if (pud_none(*pud)) {
+ pmd = (pmd_t *) spp_getpage();
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ pmd = pmd_offset(pud, phys);
+ BUG_ON(!pmd_none(*pmd));
+ set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
+ }
+}
+
+void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
+{
+ __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
+}
+
+void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
+{
+ __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
+}
+
+/*
* The head.S code sets up the kernel high mapping:
*
* from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)