[ARM] proc-v6: mark page table walks outer-cacheable, shared. Enable NX.

Mark page table walks with outer-cacheable attribute, and enable no-execute
in page tables.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/proc-v6.S

@@ -21,6 +21,14 @@
 
 #define D_CACHE_LINE_SIZE	32
 
+#define TTB_C		(1 << 0)
+#define TTB_S		(1 << 1)
+#define TTB_IMP		(1 << 2)
+#define TTB_RGN_NC	(0 << 3)
+#define TTB_RGN_WBWA	(1 << 3)
+#define TTB_RGN_WT	(2 << 3)
+#define TTB_RGN_WB	(3 << 3)
+
 	.macro	cpsie, flags
 	.ifc \flags, f
 	.long	0xf1080040
@@ -115,7 +123,7 @@ ENTRY(cpu_v6_switch_mm)
 	mov	r2, #0
 	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
 #ifdef CONFIG_SMP
-	orr	r0, r0, #2			@ set shared pgtable
+	orr	r0, r0, #TTB_RGN_WBWA|TTB_S	@ mark PTWs shared, outer cacheable
 #endif
 	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB
 	mcr	p15, 0, r2, c7, c10, 4		@ drain write buffer
@@ -161,8 +169,8 @@ ENTRY(cpu_v6_set_pte)
 	tst	r1, #L_PTE_YOUNG
 	biceq	r2, r2, #PTE_EXT_APX | PTE_EXT_AP_MASK
 
-@	tst	r1, #L_PTE_EXEC
-@	orreq	r2, r2, #PTE_EXT_XN
+	tst	r1, #L_PTE_EXEC
+	orreq	r2, r2, #PTE_EXT_XN
 
 	tst	r1, #L_PTE_PRESENT
 	moveq	r2, #0
@@ -221,7 +229,7 @@ __v6_setup:
 	mcr	p15, 0, r0, c8, c7, 0		@ invalidate I + D TLBs
 	mcr	p15, 0, r0, c2, c0, 2		@ TTB control register
 #ifdef CONFIG_SMP
-	orr	r4, r4, #2			@ set shared pgtable
+	orr	r4, r4, #TTB_RGN_WBWA|TTB_S	@ mark PTWs shared, outer cacheable
 #endif
 	mcr	p15, 0, r4, c2, c0, 1		@ load TTB1
 #ifdef CONFIG_VFP