1 files changed, 53 insertions, 15 deletions

diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index d5e160da64b2..2918c6b14659 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -23,9 +23,7 @@
 
 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
 pgd_t swapper_pg_dir[PTRS_PER_PGD];
-
-void (*copy_page)(void *from, void *to);
-void (*clear_page)(void *to);
+unsigned long cached_to_uncached = 0;
 
 void show_mem(void)
 {
@@ -102,7 +100,8 @@ static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
 
         set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
 
-        flush_tlb_one(get_asid(), addr);
+        if (cached_to_uncached)
+                flush_tlb_one(get_asid(), addr);
 }
 
 /*
@@ -131,6 +130,37 @@ void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
 
         set_pte_phys(address, phys, prot);
 }
+
+void __init page_table_range_init(unsigned long start, unsigned long end,
+                                         pgd_t *pgd_base)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        int pgd_idx;
+        unsigned long vaddr;
+
+        vaddr = start & PMD_MASK;
+        end = (end + PMD_SIZE - 1) & PMD_MASK;
+        pgd_idx = pgd_index(vaddr);
+        pgd = pgd_base + pgd_idx;
+
+        for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
+                BUG_ON(pgd_none(*pgd));
+                pud = pud_offset(pgd, 0);
+                BUG_ON(pud_none(*pud));
+                pmd = pmd_offset(pud, 0);
+
+                if (!pmd_present(*pmd)) {
+                        pte_t *pte_table;
+                        pte_table = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+                        memset(pte_table, 0, PAGE_SIZE);
+                        pmd_populate_kernel(&init_mm, pmd, pte_table);
+                }
+
+                vaddr += PMD_SIZE;
+        }
+}
 #endif  /* CONFIG_MMU */
 
 /*
@@ -150,6 +180,11 @@ void __init paging_init(void)
          * check for a null value. */
         set_TTB(swapper_pg_dir);
 
+        /* Populate the relevant portions of swapper_pg_dir so that
+         * we can use the fixmap entries without calling kmalloc.
+         * pte's will be filled in by __set_fixmap(). */
+        page_table_range_init(FIXADDR_START, FIXADDR_TOP, swapper_pg_dir);
+
         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 
         for_each_online_node(nid) {
@@ -167,9 +202,22 @@ void __init paging_init(void)
         }
 
         free_area_init_nodes(max_zone_pfns);
+
+        /* Set up the uncached fixmap */
+        set_fixmap_nocache(FIX_UNCACHED, __pa(&__uncached_start));
+
+#ifdef CONFIG_29BIT
+        /*
+         * Handle trivial transitions between cached and uncached
+         * segments, making use of the 1:1 mapping relationship in
+         * 512MB lowmem.
+         */
+        cached_to_uncached = P2SEG - P1SEG;
+#endif
 }
 
 static struct kcore_list kcore_mem, kcore_vmalloc;
+int after_bootmem = 0;
 
 void __init mem_init(void)
 {
@@ -202,17 +250,7 @@ void __init mem_init(void)
         memset(empty_zero_page, 0, PAGE_SIZE);
         __flush_wback_region(empty_zero_page, PAGE_SIZE);
 
-        /*
-         * Setup wrappers for copy/clear_page(), these will get overridden
-         * later in the boot process if a better method is available.
-         */
-#ifdef CONFIG_MMU
-        copy_page = copy_page_slow;
-        clear_page = clear_page_slow;
-#else
-        copy_page = copy_page_nommu;
-        clear_page = clear_page_nommu;
-#endif
+        after_bootmem = 1;
 
         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;