[PATCH] pxa3xx_nand: introduce common timing to reduce read id times

Lei Wen leiwen at marvell.com
Sun Mar 21 22:24:48 EDT 2010


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

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;
 	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;
 }

-- 
1.5.6.5



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