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>

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| \

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 */