1 files changed, 58 insertions, 35 deletions

diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 2be9139a4ef..feacf4c7671 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -1,9 +1,38 @@
 #include <linux/kernel.h>
 
 #include <asm/cputype.h>
+#include <asm/idmap.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
+#include <asm/sections.h>
 
+pgd_t *idmap_pgd;
+
+#ifdef CONFIG_ARM_LPAE
+static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
+        unsigned long prot)
+{
+        pmd_t *pmd;
+        unsigned long next;
+
+        if (pud_none_or_clear_bad(pud) || (pud_val(*pud) & L_PGD_SWAPPER)) {
+                pmd = pmd_alloc_one(&init_mm, addr);
+                if (!pmd) {
+                        pr_warning("Failed to allocate identity pmd.\n");
+                        return;
+                }
+                pud_populate(&init_mm, pud, pmd);
+                pmd += pmd_index(addr);
+        } else
+                pmd = pmd_offset(pud, addr);
+
+        do {
+                next = pmd_addr_end(addr, end);
+                *pmd = __pmd((addr & PMD_MASK) | prot);
+                flush_pmd_entry(pmd);
+        } while (pmd++, addr = next, addr != end);
+}
+#else   /* !CONFIG_ARM_LPAE */
 static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
         unsigned long prot)
 {
@@ -15,6 +44,7 @@ static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
         pmd[1] = __pmd(addr);
         flush_pmd_entry(pmd);
 }
+#endif  /* CONFIG_ARM_LPAE */
 
 static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
         unsigned long prot)
@@ -28,11 +58,11 @@ static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
         } while (pud++, addr = next, addr != end);
 }
 
-void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
+static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
 {
         unsigned long prot, next;
 
-        prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
+        prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;
         if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
                 prot |= PMD_BIT4;
 
@@ -43,48 +73,41 @@ void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
         } while (pgd++, addr = next, addr != end);
 }
 
-#ifdef CONFIG_SMP
-static void idmap_del_pmd(pud_t *pud, unsigned long addr, unsigned long end)
-{
-        pmd_t *pmd = pmd_offset(pud, addr);
-        pmd_clear(pmd);
-}
+extern char  __idmap_text_start[], __idmap_text_end[];
 
-static void idmap_del_pud(pgd_t *pgd, unsigned long addr, unsigned long end)
+static int __init init_static_idmap(void)
 {
-        pud_t *pud = pud_offset(pgd, addr);
-        unsigned long next;
+        phys_addr_t idmap_start, idmap_end;
 
-        do {
-                next = pud_addr_end(addr, end);
-                idmap_del_pmd(pud, addr, next);
-        } while (pud++, addr = next, addr != end);
-}
+        idmap_pgd = pgd_alloc(&init_mm);
+        if (!idmap_pgd)
+                return -ENOMEM;
 
-void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
-{
-        unsigned long next;
+        /* Add an identity mapping for the physical address of the section. */
+        idmap_start = virt_to_phys((void *)__idmap_text_start);
+        idmap_end = virt_to_phys((void *)__idmap_text_end);
 
-        pgd += pgd_index(addr);
-        do {
-                next = pgd_addr_end(addr, end);
-                idmap_del_pud(pgd, addr, next);
-        } while (pgd++, addr = next, addr != end);
+        pr_info("Setting up static identity map for 0x%llx - 0x%llx\n",
+                (long long)idmap_start, (long long)idmap_end);
+        identity_mapping_add(idmap_pgd, idmap_start, idmap_end);
+
+        return 0;
 }
-#endif
+early_initcall(init_static_idmap);
 
 /*
- * In order to soft-boot, we need to insert a 1:1 mapping in place of
- * the user-mode pages.  This will then ensure that we have predictable
- * results when turning the mmu off
+ * In order to soft-boot, we need to switch to a 1:1 mapping for the
+ * cpu_reset functions. This will then ensure that we have predictable
+ * results when turning off the mmu.
  */
-void setup_mm_for_reboot(char mode)
+void setup_mm_for_reboot(void)
 {
-        /*
-         * We need to access to user-mode page tables here. For kernel threads
-         * we don't have any user-mode mappings so we use the context that we
-         * "borrowed".
-         */
-        identity_mapping_add(current->active_mm->pgd, 0, TASK_SIZE);
+        /* Clean and invalidate L1. */
+        flush_cache_all();
+
+        /* Switch to the identity mapping. */
+        cpu_switch_mm(idmap_pgd, &init_mm);
+
+        /* Flush the TLB. */
         local_flush_tlb_all();
 }