Merge branches 'pm-core', 'pm-qos', 'pm-domains' and 'pm-opp'

[linux.git] / arch / x86 / kernel / head32.c

diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index f16c55bfc0907bc4a3b1f35174ca5f5cbc53ce99..e5fb436a6548a9111f95ce3afacf787f5bec278c 100644 (file)
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -49,3 +49,65 @@ asmlinkage __visible void __init i386_start_kernel(void)
 
        start_kernel();
 }
+
+/*
+ * Initialize page tables.  This creates a PDE and a set of page
+ * tables, which are located immediately beyond __brk_base.  The variable
+ * _brk_end is set up to point to the first "safe" location.
+ * Mappings are created both at virtual address 0 (identity mapping)
+ * and PAGE_OFFSET for up to _end.
+ *
+ * In PAE mode initial_page_table is statically defined to contain
+ * enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3
+ * entries). The identity mapping is handled by pointing two PGD entries
+ * to the first kernel PMD. Note the upper half of each PMD or PTE are
+ * always zero at this stage.
+ */
+void __init mk_early_pgtbl_32(void)
+{
+#ifdef __pa
+#undef __pa
+#endif
+#define __pa(x)  ((unsigned long)(x) - PAGE_OFFSET)
+       pte_t pte, *ptep;
+       int i;
+       unsigned long *ptr;
+       /* Enough space to fit pagetables for the low memory linear map */
+       const unsigned long limit = __pa(_end) +
+               (PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT);
+#ifdef CONFIG_X86_PAE
+       pmd_t pl2, *pl2p = (pmd_t *)__pa(initial_pg_pmd);
+#define SET_PL2(pl2, val)    { (pl2).pmd = (val); }
+#else
+       pgd_t pl2, *pl2p = (pgd_t *)__pa(initial_page_table);
+#define SET_PL2(pl2, val)   { (pl2).pgd = (val); }
+#endif
+
+       ptep = (pte_t *)__pa(__brk_base);
+       pte.pte = PTE_IDENT_ATTR;
+
+       while ((pte.pte & PTE_PFN_MASK) < limit) {
+
+               SET_PL2(pl2, (unsigned long)ptep | PDE_IDENT_ATTR);
+               *pl2p = pl2;
+#ifndef CONFIG_X86_PAE
+               /* Kernel PDE entry */
+               *(pl2p +  ((PAGE_OFFSET >> PGDIR_SHIFT))) = pl2;
+#endif
+               for (i = 0; i < PTRS_PER_PTE; i++) {
+                       *ptep = pte;
+                       pte.pte += PAGE_SIZE;
+                       ptep++;
+               }
+
+               pl2p++;
+       }
+
+       ptr = (unsigned long *)__pa(&max_pfn_mapped);
+       /* Can't use pte_pfn() since it's a call with CONFIG_PARAVIRT */
+       *ptr = (pte.pte & PTE_PFN_MASK) >> PAGE_SHIFT;
+
+       ptr = (unsigned long *)__pa(&_brk_end);
+       *ptr = (unsigned long)ptep + PAGE_OFFSET;
+}
+