Patchwork [02/20] pxa3xx_nand: introduce common timing to reduce read id times

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Submitter Haojian Zhuang
Date May 6, 2010, 9:02 a.m.
Message ID <i2q771cded01005060202vefaec1d0t8d51782fe80108fe@mail.gmail.com>
Download mbox | patch
Permalink /patch/51799/
State New
Headers show

Comments

Haojian Zhuang - May 6, 2010, 9:02 a.m.
From e1c5e6173aa104eb978727d48557a29dc87336cb Mon Sep 17 00:00:00 2001
From: Lei Wen <leiwen@marvell.com>
Date: Mon, 22 Mar 2010 10:24:48 +0800
Subject: [PATCH] pxa3xx_nand: introduce common timing to reduce read id times

We certainly don't need to send read id command times by times, since
we already know what the id is after the first read id...

So create a common timing which could ensure it would successfully read id
out all supported chip. Then follow the build-in table to reconfigure
the timing.

Signed-off-by: Lei Wen <leiwen@marvell.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
---
 drivers/mtd/nand/pxa3xx_nand.c |   33 +++++++++++++++++----------------
 1 files changed, 17 insertions(+), 16 deletions(-)

 	info->read_id_bytes = (f->page_size == 2048) ? 4 : 2;
@@ -967,23 +967,24 @@ static int pxa3xx_nand_detect_flash(struct
pxa3xx_nand_info *info,
 		if (pxa3xx_nand_detect_config(info) == 0)
 			return 0;

-	for (i = 0; i < ARRAY_SIZE(builtin_flash_types); i++) {
+	f = &builtin_flash_types[0];
+	pxa3xx_nand_config_flash(info, f);
+	if (__readid(info, &id))
+		goto fail_detect;

+	for (i = 1; i < ARRAY_SIZE(builtin_flash_types); i++) {
 		f = &builtin_flash_types[i];
-
-		if (pxa3xx_nand_config_flash(info, f))
-			continue;
-
-		if (__readid(info, &id))
-			continue;
-
-		if (id == f->chip_id)
+		if (f->chip_id == id) {
+			dev_info(&info->pdev->dev, "detect chip id: 0x%x\n", id);
+			pxa3xx_nand_config_flash(info, f);
 			return 0;
+		}
 	}

 	dev_warn(&info->pdev->dev,
-		 "failed to detect configured nand flash; found %04x instead of\n",
+			"failed to detect configured nand flash; found %04x instead of\n",
 		 id);
+fail_detect:
 	return -ENODEV;
 }

Patch

diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
index da40b9a..5658398 100644
--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -225,7 +225,13 @@  const static struct pxa3xx_nand_cmdset cmdset = {
 	.lock_status	= 0x007A,
 };

+/**
+ * The timing defined in the builtin_flash_types[0]
+ * could be considered as the common timing which is used to
+ * detect the chip id before we know how to optimize further
+ */
 static struct pxa3xx_nand_flash __devinitdata builtin_flash_types[] = {
+{ 0, 0, 0, 0, 0, 0, { 40, 80, 60, 100, 80, 100, 90000, 400, 40, }, },
 { 0x46ec, 32, 512, 16, 16, 4096, { 10, 0, 20, 40, 30, 40, 11123, 110, 10, }, },
 { 0xdaec, 64, 2048, 8, 8, 2048, { 10, 0, 20, 40, 30, 40, 11123, 110, 10, }, },
 { 0xd7ec, 128, 4096, 8, 8, 8192, { 10, 0, 20, 40, 30, 40, 11123, 110, 10, }, },
@@ -850,12 +856,6 @@  static int pxa3xx_nand_config_flash(struct
pxa3xx_nand_info *info,
 	struct pxa3xx_nand_platform_data *pdata = pdev->dev.platform_data;
 	uint32_t ndcr = 0x00000FFF; /* disable all interrupts */

-	if (f->page_size != 2048 && f->page_size != 512)
-		return -EINVAL;
-
-	if (f->flash_width != 16 && f->flash_width != 8)
-		return -EINVAL;
-
 	/* calculate flash information */
 	info->oob_size = (f->page_size == 2048) ? 64 : 16;