[PATCHv2] [ARM] orion5x: accelerate NAND on the TS-78xx

[Alexander Clouter]

Hi,

No grumblings from anyone?

Cheers

* Alexander Clouter <alex at digriz.org.uk> [2011-01-08 11:55:25+0000]:
>
> 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
> 
> Changelog:
>  v2: used approach suggested by Russell King instead
> 	<20110105003316.GJ24935 at n2100.arm.linux.org.uk>
>  v1: initial release <20110104235158.GQ12386 at chipmunk>
> 
> Signed-off-by: Alexander Clouter <alex at digriz.org.uk>
> ---
>  arch/arm/mach-orion5x/ts78xx-setup.c |   56 ++++++++++++++++++++++++++++++++++
>  1 files changed, 56 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/mach-orion5x/ts78xx-setup.c b/arch/arm/mach-orion5x/ts78xx-setup.c
> index c1c1cd0..89682e1 100644
> --- a/arch/arm/mach-orion5x/ts78xx-setup.c
> +++ b/arch/arm/mach-orion5x/ts78xx-setup.c
> @@ -191,6 +191,60 @@ 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;
> +	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;
> +	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);
> +}
> +
>  const char *ts_nand_part_probes[] = { "cmdlinepart", NULL };
>  
>  static struct mtd_partition ts78xx_ts_nand_parts[] = {
> @@ -233,6 +287,8 @@ 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,
>  	},
>  };
>  
>

-- 
Alexander Clouter
.sigmonster says: TV is chewing gum for the eyes.
                  		-- Frank Lloyd Wright