ARM: 8031/2: change fixmap mapping region to support 32 CPUs

In 32-bit ARM systems, the fixmap mapping region can support no more
than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS
up to 32. So there is a mismatch.

This patch moves fixmapping region downwards to region 0xffc00000-
0xffe00000. Then the fixmap mapping region can support up to 32 CPUs.

Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 3 insertions, 14 deletions

diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h
index be55ebc08ed4..74124b0d0d79 100644
--- a/arch/arm/include/asm/fixmap.h
+++ b/arch/arm/include/asm/fixmap.h
@@ -1,20 +1,8 @@
 #ifndef _ASM_FIXMAP_H
 #define _ASM_FIXMAP_H
 
-/*
- * Nothing too fancy for now.
- *
- * On ARM we already have well known fixed virtual addresses imposed by
- * the architecture such as the vector page which is located at 0xffff0000,
- * therefore a second level page table is already allocated covering
- * 0xfff00000 upwards.
- *
- * The cache flushing code in proc-xscale.S uses the virtual area between
- * 0xfffe0000 and 0xfffeffff.
- */
-
-#define FIXADDR_START           0xfff00000UL
-#define FIXADDR_TOP             0xfffe0000UL
+#define FIXADDR_START           0xffc00000UL
+#define FIXADDR_TOP             0xffe00000UL
 #define FIXADDR_SIZE            (FIXADDR_TOP - FIXADDR_START)
 
 #define FIX_KMAP_NR_PTES        (FIXADDR_SIZE >> PAGE_SHIFT)
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index 91b99abe7a95..535579511ed0 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -18,6 +18,7 @@
         } while (0)
 
 extern pte_t *pkmap_page_table;
+extern pte_t *fixmap_page_table;
 
 extern void *kmap_high(struct page *page);
 extern void kunmap_high(struct page *page);