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Diffstat (limited to 'arch/arm/mm/idmap.c')
-rw-r--r--arch/arm/mm/idmap.c93
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();
}