[PATCH] powerpc: use string library

[Akinobu Mita]

- Use memchr_inv to check if the data contains all 0xFF bytes.
  It is faster than looping for each byte.

- Use memcmp to compare memory areas

Signed-off-by: Akinobu Mita <akinobu.m...@gmail.com>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/platforms/powermac/nvram.c |   42 ++++++++++++++-----------------
 1 files changed, 19 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/platforms/powermac/nvram.c 
b/arch/powerpc/platforms/powermac/nvram.c
index 54d2271..da18b26 100644
--- a/arch/powerpc/platforms/powermac/nvram.c
+++ b/arch/powerpc/platforms/powermac/nvram.c
@@ -279,7 +279,7 @@ static u32 core99_check(u8* datas)
 
 static int sm_erase_bank(int bank)
 {
-       int stat, i;
+       int stat;
        unsigned long timeout;
 
        u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
@@ -301,11 +301,10 @@ static int sm_erase_bank(int bank)
        out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
        out_8(base, SM_FLASH_CMD_RESET);
 
-       for (i=0; i<NVRAM_SIZE; i++)
-               if (base[i] != 0xff) {
-                       printk(KERN_ERR "nvram: Sharp/Micron flash erase failed 
!\n");
-                       return -ENXIO;
-               }
+       if (memchr_inv(base, 0xff, NVRAM_SIZE)) {
+               printk(KERN_ERR "nvram: Sharp/Micron flash erase failed !\n");
+               return -ENXIO;
+       }
        return 0;
 }
 
@@ -336,17 +335,16 @@ static int sm_write_bank(int bank, u8* datas)
        }
        out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
        out_8(base, SM_FLASH_CMD_RESET);
-       for (i=0; i<NVRAM_SIZE; i++)
-               if (base[i] != datas[i]) {
-                       printk(KERN_ERR "nvram: Sharp/Micron flash write failed 
!\n");
-                       return -ENXIO;
-               }
+       if (memcmp(base, datas, NVRAM_SIZE)) {
+               printk(KERN_ERR "nvram: Sharp/Micron flash write failed !\n");
+               return -ENXIO;
+       }
        return 0;
 }
 
 static int amd_erase_bank(int bank)
 {
-       int i, stat = 0;
+       int stat = 0;
        unsigned long timeout;
 
        u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
@@ -382,12 +380,11 @@ static int amd_erase_bank(int bank)
        /* Reset */
        out_8(base, 0xf0);
        udelay(1);
-       
-       for (i=0; i<NVRAM_SIZE; i++)
-               if (base[i] != 0xff) {
-                       printk(KERN_ERR "nvram: AMD flash erase failed !\n");
-                       return -ENXIO;
-               }
+
+       if (memchr_inv(base, 0xff, NVRAM_SIZE)) {
+               printk(KERN_ERR "nvram: AMD flash erase failed !\n");
+               return -ENXIO;
+       }
        return 0;
 }
 
@@ -429,11 +426,10 @@ static int amd_write_bank(int bank, u8* datas)
        out_8(base, 0xf0);
        udelay(1);
 
-       for (i=0; i<NVRAM_SIZE; i++)
-               if (base[i] != datas[i]) {
-                       printk(KERN_ERR "nvram: AMD flash write failed !\n");
-                       return -ENXIO;
-               }
+       if (memcmp(base, datas, NVRAM_SIZE)) {
+               printk(KERN_ERR "nvram: AMD flash write failed !\n");
+               return -ENXIO;
+       }
        return 0;
 }
 
-- 
1.7.4.4

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