+/*
+ * Initialize the highest priority protection region, PR7
+ * to cover all 32bit address and cacheable and bufferable.
+ */
+__armv4_mpu_cache_on:
+ mov r0, #0x3f @ 4G, the whole
+ mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting
+ mcr p15, 0, r0, c6, c7, 1
+
+ mov r0, #0x80 @ PR7
+ mcr p15, 0, r0, c2, c0, 0 @ D-cache on
+ mcr p15, 0, r0, c2, c0, 1 @ I-cache on
+ mcr p15, 0, r0, c3, c0, 0 @ write-buffer on
+
+ mov r0, #0xc000
+ mcr p15, 0, r0, c5, c0, 1 @ I-access permission
+ mcr p15, 0, r0, c5, c0, 0 @ D-access permission
+
+ mov r0, #0
+ mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
+ mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache
+ mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache
+ mrc p15, 0, r0, c1, c0, 0 @ read control reg
+ @ ...I .... ..D. WC.M
+ orr r0, r0, #0x002d @ .... .... ..1. 11.1
+ orr r0, r0, #0x1000 @ ...1 .... .... ....
+
+ mcr p15, 0, r0, c1, c0, 0 @ write control reg
+
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache
+ mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache
+ mov pc, lr
+
+__armv3_mpu_cache_on:
+ mov r0, #0x3f @ 4G, the whole
+ mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting
+
+ mov r0, #0x80 @ PR7
+ mcr p15, 0, r0, c2, c0, 0 @ cache on
+ mcr p15, 0, r0, c3, c0, 0 @ write-buffer on
+
+ mov r0, #0xc000
+ mcr p15, 0, r0, c5, c0, 0 @ access permission
+
+ mov r0, #0
+ mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
+ mrc p15, 0, r0, c1, c0, 0 @ read control reg
+ @ .... .... .... WC.M
+ orr r0, r0, #0x000d @ .... .... .... 11.1
+ mov r0, #0
+ mcr p15, 0, r0, c1, c0, 0 @ write control reg
+
+ mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
+ mov pc, lr
+