linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Akinobu Mita <akinobu.mita@gmail.com>
To: linux-kernel@vger.kernel.org, akpm@linux-foundation.org
Cc: Akinobu Mita <akinobu.mita@gmail.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	linuxppc-dev@lists.ozlabs.org
Subject: [PATCH] powerpc: use string library
Date: Fri, 27 Jan 2012 23:24:48 +0900	[thread overview]
Message-ID: <1327674295-3700-1-git-send-email-akinobu.mita@gmail.com> (raw)

- 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.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@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


             reply	other threads:[~2012-01-27 14:24 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-27 14:24 Akinobu Mita [this message]
2012-01-27 14:24 ` [PATCH] mtd/nand: use string library Akinobu Mita
2012-01-27 17:16   ` Joe Perches
2012-01-27 18:52     ` Brian Norris
2012-01-27 23:52       ` Akinobu Mita
2012-01-31 17:57         ` Brian Norris
2012-02-01 13:11           ` Akinobu Mita
2012-01-27 14:24 ` [PATCH] mtd/onenand: " Akinobu Mita
2012-01-27 14:24 ` [PATCH] mtd/ubi: use memchr_inv Akinobu Mita
2012-01-27 14:24 ` [PATCH] mtd/inftlmount: " Akinobu Mita
2012-01-27 14:24 ` [PATCH] mtd/nftlmount: " Akinobu Mita
2012-01-27 14:24 ` [PATCH] mtd/tests: " Akinobu Mita
2012-01-27 14:24 ` [PATCH] mISDN: " Akinobu Mita
2012-02-01 19:15   ` David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1327674295-3700-1-git-send-email-akinobu.mita@gmail.com \
    --to=akinobu.mita@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=benh@kernel.crashing.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).