sh: Better description of SH-4 PTEA register update.

Signed-off-by: Michael Trimarchi <trimarchimichael@yahoo.it>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 14 insertions, 3 deletions

diff --git a/arch/sh/include/asm/pgtable_32.h b/arch/sh/include/asm/pgtable_32.h
index 0db19db913c..4c4429cda56 100644
--- a/arch/sh/include/asm/pgtable_32.h
+++ b/arch/sh/include/asm/pgtable_32.h
@@ -87,6 +87,14 @@
 #define _PAGE_PCC_ATR8  0x60000000      /* Attribute Memory space, 8 bit bus */
 #define _PAGE_PCC_ATR16 0x60000001      /* Attribute Memory space, 6 bit bus */
 
+#ifndef CONFIG_X2TLB
+/* copy the ptea attributes */
+static inline unsigned long copy_ptea_attributes(unsigned long x)
+{
+        return  ((x >> 28) & 0xe) | (x & 0x1);
+}
+#endif
+
 /* Mask which drops unused bits from the PTEL value */
 #if defined(CONFIG_CPU_SH3)
 #define _PAGE_CLEAR_FLAGS       (_PAGE_PROTNONE | _PAGE_ACCESSED| \
diff --git a/arch/sh/mm/tlb-sh4.c b/arch/sh/mm/tlb-sh4.c
index f0c7b7397fa..fd0d11f1a81 100644
--- a/arch/sh/mm/tlb-sh4.c
+++ b/arch/sh/mm/tlb-sh4.c
@@ -61,9 +61,12 @@ void update_mmu_cache(struct vm_area_struct * vma,
          */
         ctrl_outl(pte.pte_high, MMU_PTEA);
 #else
-        if (cpu_data->flags & CPU_HAS_PTEA)
-                /* TODO: make this look less hacky */
-                ctrl_outl(((pteval >> 28) & 0xe) | (pteval & 0x1), MMU_PTEA);
+        if (cpu_data->flags & CPU_HAS_PTEA) {
+                /* The last 3 bits and the first one of pteval contains
+                 * the PTEA timing control and space attribute bits
+                 */
+                ctrl_outl(copy_ptea_attributes(pteval), MMU_PTEA);
+        }
 #endif
 
         /* Set PTEL register */