diff options
| author | Nicolas Pitre <nico@cam.org> | 2009-05-31 22:25:40 -0400 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2009-06-08 12:26:59 +0100 |
| commit | bfee1a4311702c9fdecd8264ffd1126fd0ce92fb (patch) | |
| tree | 71cdaa7d43688b6ee2a14210f4ec2391a7b84c62 | |
| parent | 9dbc090274668abe3fc9f3a5de490d7d412cd74a (diff) | |
mtd: orion_nand: use burst reads with double word accesses
This is not 8 times faster than byte access, but still around 60% faster.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| -rw-r--r-- | drivers/mtd/nand/orion_nand.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/mtd/nand/orion_nand.c b/drivers/mtd/nand/orion_nand.c index c2dfd3ea353..7ad972229db 100644 --- a/drivers/mtd/nand/orion_nand.c +++ b/drivers/mtd/nand/orion_nand.c @@ -47,6 +47,28 @@ static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl writeb(cmd, nc->IO_ADDR_W + offs); } +static void orion_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; + uint64_t *buf64; + int i = 0; + + while (len && (unsigned long)buf & 7) { + *buf++ = readb(io_base); + len--; + } + buf64 = (uint64_t *)buf; + while (i < len/8) { + uint64_t x; + asm ("ldrd\t%0, [%1]" : "=r" (x) : "r" (io_base)); + buf64[i++] = x; + } + i *= 8; + while (i < len) + buf[i++] = readb(io_base); +} + static int __init orion_nand_probe(struct platform_device *pdev) { struct mtd_info *mtd; @@ -83,6 +105,7 @@ static int __init orion_nand_probe(struct platform_device *pdev) nc->priv = board; nc->IO_ADDR_R = nc->IO_ADDR_W = io_base; nc->cmd_ctrl = orion_nand_cmd_ctrl; + nc->read_buf = orion_nand_read_buf; nc->ecc.mode = NAND_ECC_SOFT; if (board->chip_delay) |