1 files changed, 42 insertions, 1 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index d4d082c5c2d4..b438fc4fb77b 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -18,9 +18,11 @@
 #include <asm/cputype.h>
 #include <asm/mach-types.h>
 #include <asm/sections.h>
+#include <asm/cachetype.h>
 #include <asm/setup.h>
 #include <asm/sizes.h>
 #include <asm/tlb.h>
+#include <asm/highmem.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
@@ -243,6 +245,10 @@ static struct mem_type mem_types[] = {
                 .prot_sect = PMD_TYPE_SECT,
                 .domain    = DOMAIN_KERNEL,
         },
+        [MT_MEMORY_NONCACHED] = {
+                .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
+                .domain    = DOMAIN_KERNEL,
+        },
 };
 
 const struct mem_type *get_mem_type(unsigned int type)
@@ -406,9 +412,28 @@ static void __init build_mem_type_table(void)
                 kern_pgprot |= L_PTE_SHARED;
                 vecs_pgprot |= L_PTE_SHARED;
                 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
+                mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
 #endif
         }
 
+        /*
+         * Non-cacheable Normal - intended for memory areas that must
+         * not cause dirty cache line writebacks when used
+         */
+        if (cpu_arch >= CPU_ARCH_ARMv6) {
+                if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
+                        /* Non-cacheable Normal is XCB = 001 */
+                        mem_types[MT_MEMORY_NONCACHED].prot_sect |=
+                                PMD_SECT_BUFFERED;
+                } else {
+                        /* For both ARMv6 and non-TEX-remapping ARMv7 */
+                        mem_types[MT_MEMORY_NONCACHED].prot_sect |=
+                                PMD_SECT_TEX(1);
+                }
+        } else {
+                mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
+        }
+
         for (i = 0; i < 16; i++) {
                 unsigned long v = pgprot_val(protection_map[i]);
                 protection_map[i] = __pgprot(v | user_pgprot);
@@ -677,6 +702,10 @@ static void __init sanity_check_meminfo(void)
                         if (meminfo.nr_banks >= NR_BANKS) {
                                 printk(KERN_CRIT "NR_BANKS too low, "
                                                  "ignoring high memory\n");
+                        } else if (cache_is_vipt_aliasing()) {
+                                printk(KERN_CRIT "HIGHMEM is not yet supported "
+                                                 "with VIPT aliasing cache, "
+                                                 "ignoring high memory\n");
                         } else {
                                 memmove(bank + 1, bank,
                                         (meminfo.nr_banks - i) * sizeof(*bank));
@@ -694,7 +723,7 @@ static void __init sanity_check_meminfo(void)
                  * the vmalloc area.
                  */
                 if (__va(bank->start) >= VMALLOC_MIN ||
-                    __va(bank->start) < PAGE_OFFSET) {
+                    __va(bank->start) < (void *)PAGE_OFFSET) {
                         printk(KERN_NOTICE "Ignoring RAM at %.8lx-%.8lx "
                                "(vmalloc region overlap).\n",
                                bank->start, bank->start + bank->size - 1);
@@ -895,6 +924,17 @@ static void __init devicemaps_init(struct machine_desc *mdesc)
         flush_cache_all();
 }
 
+static void __init kmap_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+        pmd_t *pmd = pmd_off_k(PKMAP_BASE);
+        pte_t *pte = alloc_bootmem_low_pages(2 * PTRS_PER_PTE * sizeof(pte_t));
+        BUG_ON(!pmd_none(*pmd) || !pte);
+        __pmd_populate(pmd, __pa(pte) | _PAGE_KERNEL_TABLE);
+        pkmap_page_table = pte + PTRS_PER_PTE;
+#endif
+}
+
 /*
  * paging_init() sets up the page tables, initialises the zone memory
  * maps, and sets up the zero page, bad page and bad page tables.
@@ -908,6 +948,7 @@ void __init paging_init(struct machine_desc *mdesc)
         prepare_page_table();
         bootmem_init();
         devicemaps_init(mdesc);
+        kmap_init();
 
         top_pmd = pmd_off_k(0xffff0000);