[Blackfin] arch: Initial checkin of the memory protection support.
Enable it with CONFIG_MPU.
Signed-off-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c
index a03c2df..1a942a7 100644
--- a/arch/blackfin/kernel/setup.c
+++ b/arch/blackfin/kernel/setup.c
@@ -238,7 +238,12 @@
memory_end = _ramend - DMA_UNCACHED_REGION;
_ramstart = (unsigned long)__bss_stop;
+#ifdef CONFIG_MPU
+ /* Round up to multiple of 4MB. */
+ memory_start = (_ramstart + 0x3fffff) & ~0x3fffff;
+#else
memory_start = PAGE_ALIGN(_ramstart);
+#endif
#if defined(CONFIG_MTD_UCLINUX)
/* generic memory mapped MTD driver */
@@ -307,6 +312,11 @@
printk(KERN_NOTICE "Warning: limiting memory to %liMB due to hardware anomaly 05000263\n", memory_end >> 20);
#endif /* ANOMALY_05000263 */
+#ifdef CONFIG_MPU
+ page_mask_nelts = ((_ramend >> PAGE_SHIFT) + 31) / 32;
+ page_mask_order = get_order(3 * page_mask_nelts * sizeof(long));
+#endif
+
#if !defined(CONFIG_MTD_UCLINUX)
memory_end -= SIZE_4K; /*In case there is no valid CPLB behind memory_end make sure we don't get to close*/
#endif