1 files changed, 63 insertions, 3 deletions

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 6aa13d59c858..7eac87f05180 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -33,8 +33,8 @@
 #include <asm/sizes.h>
 
 /*
- * Used by ioremap() and iounmap() code to mark section-mapped I/O regions
- * in vm_struct->flags field.
+ * Used by ioremap() and iounmap() code to mark (super)section-mapped
+ * I/O regions in vm_struct->flags field.
  */
 #define VM_ARM_SECTION_MAPPING  0x80000000
 
@@ -233,6 +233,54 @@ remap_area_sections(unsigned long virt, unsigned long pfn,
 
         return 0;
 }
+
+static int
+remap_area_supersections(unsigned long virt, unsigned long pfn,
+                         unsigned long size, unsigned long flags)
+{
+        unsigned long prot, addr = virt, end = virt + size;
+        pgd_t *pgd;
+
+        /*
+         * Remove and free any PTE-based mapping, and
+         * sync the current kernel mapping.
+         */
+        unmap_area_sections(virt, size);
+
+        prot = PMD_TYPE_SECT | PMD_SECT_SUPER | PMD_SECT_AP_WRITE |
+                        PMD_DOMAIN(DOMAIN_IO) |
+                        (flags & (L_PTE_CACHEABLE | L_PTE_BUFFERABLE));
+
+        /*
+         * ARMv6 and above need XN set to prevent speculative prefetches
+         * hitting IO.
+         */
+        if (cpu_architecture() >= CPU_ARCH_ARMv6)
+                prot |= PMD_SECT_XN;
+
+        pgd = pgd_offset_k(virt);
+        do {
+                unsigned long super_pmd_val, i;
+
+                super_pmd_val = __pfn_to_phys(pfn) | prot;
+                super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
+
+                for (i = 0; i < 8; i++) {
+                        pmd_t *pmd = pmd_offset(pgd, addr);
+
+                        pmd[0] = __pmd(super_pmd_val);
+                        pmd[1] = __pmd(super_pmd_val);
+                        flush_pmd_entry(pmd);
+
+                        addr += PGDIR_SIZE;
+                        pgd++;
+                }
+
+                pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
+        } while (addr < end);
+
+        return 0;
+}
 #endif
 
 
@@ -255,6 +303,13 @@ __ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
         int err;
         unsigned long addr;
         struct vm_struct * area;
+        unsigned int cr = get_cr();
+
+        /*
+         * High mappings must be supersection aligned
+         */
+        if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK))
+                return NULL;
 
         area = get_vm_area(size, VM_IOREMAP);
         if (!area)
@@ -262,7 +317,12 @@ __ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
         addr = (unsigned long)area->addr;
 
 #ifndef CONFIG_SMP
-        if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) {
+        if ((((cpu_architecture() >= CPU_ARCH_ARMv6) && (cr & CR_XP)) ||
+               cpu_is_xsc3()) &&
+               !((__pfn_to_phys(pfn) | size | addr) & ~SUPERSECTION_MASK)) {
+                area->flags |= VM_ARM_SECTION_MAPPING;
+                err = remap_area_supersections(addr, pfn, size, flags);
+        } else if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) {
                 area->flags |= VM_ARM_SECTION_MAPPING;
                 err = remap_area_sections(addr, pfn, size, flags);
         } else