[PATCH] [ARM] orion5x: accelerate NAND on the TS-78xx
From: Russell King - ARM Linux <hidden>
Date: 2011-01-05 00:33:16
On Tue, Jan 04, 2011 at 11:51:59PM +0000, Alexander Clouter wrote:
The NAND supports 32bit reads and writes so lets stop shunting 8bit chunks across the bus. Doing a dumb 'dd' benchmark, this increases performance roughly like so: * read: 1.3MB/s to 3.4MB/s * write: 614kB/s to 882kB/s
Try something like the below. It's slightly more typing, but the underlying string IO functions should improve your transfer speed. Note that they won't do endian conversions.
quoted hunk ↗ jump to hunk
Signed-off-by: Alexander Clouter <alex@digriz.org.uk> --- arch/arm/mach-orion5x/ts78xx-setup.c | 42 ++++++++++++++++++++++++++++++++++ 1 files changed, 42 insertions(+), 0 deletions(-)diff --git a/arch/arm/mach-orion5x/ts78xx-setup.c b/arch/arm/mach-orion5x/ts78xx-setup.c index 9a5d1ef..bcc21fe 100644 --- a/arch/arm/mach-orion5x/ts78xx-setup.c +++ b/arch/arm/mach-orion5x/ts78xx-setup.c@@ -191,6 +191,46 @@ static int ts78xx_ts_nand_dev_ready(struct mtd_info *mtd) return readb(TS_NAND_CTRL) & 0x20; } +static void ts78xx_ts_nand_write_buf(struct mtd_info *mtd, + const uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd->priv; + void __iomem *io_base = chip->IO_ADDR_W; + uint32_t *buf32; + int i = 0; + + while (len && (unsigned int)buf & 3) { + writeb(*buf++, io_base); + len--; + } + buf32 = (uint32_t *)buf; + while (i < len/4) + writel(buf32[i++], io_base); + i *= 4; + while (i < len) + writeb(buf[i++], io_base);
unsigned long off = ((unsigned long)buf & 3);
int sz;
if (off) {
sz = min(4 - off, len);
writesb(io_base, buf, sz);
buf += sz;
len -= sz;
}
sz = len >> 2;
if (sz) {
u32 *buf32 = (u32 *)buf;
writesl(io_base, buf32, sz);
buf += sz << 2;
len -= sz << 2;
}
if (len)
writesb(io_base, buf, len);
+}
+
+static void ts78xx_ts_nand_read_buf(struct mtd_info *mtd,
+ uint8_t *buf, int len)
+{
+ struct nand_chip *chip = mtd->priv;
+ void __iomem *io_base = chip->IO_ADDR_R;
+ uint32_t *buf32;
+ int i = 0;
+
+ while (len && (unsigned int)buf & 3) {
+ *buf++ = readb(io_base);
+ len--;
+ }
+ buf32 = (uint32_t *)buf;
+ while (i < len/4)
+ buf32[i++] = readl(io_base);
+ i *= 4;
+ while (i < len)
+ buf[i++] = readb(io_base);
unsigned long off = ((unsigned long)buf & 3);
int sz;
if (off) {
sz = min(4 - off, len);
readsb(io_base, buf, sz);
buf += sz;
len -= sz;
}
sz = len >> 2;
if (sz) {
u32 *buf32 = (u32 *)buf;
readsl(io_base, buf32, sz);
buf += sz << 2;
len -= sz << 2;
}
if (len)
readsb(io_base, buf, len);
quoted hunk ↗ jump to hunk
+} + const char *ts_nand_part_probes[] = { "cmdlinepart", NULL }; static struct mtd_partition ts78xx_ts_nand_parts[] = {@@ -233,6 +273,8 @@ static struct platform_nand_data ts78xx_ts_nand_data = { */ .cmd_ctrl = ts78xx_ts_nand_cmd_ctrl, .dev_ready = ts78xx_ts_nand_dev_ready, + .write_buf = ts78xx_ts_nand_write_buf, + .read_buf = ts78xx_ts_nand_read_buf, }, };-- 1.7.2.3 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel at lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel