[ARM] orion5x: accelerate NAND on the TS-78xx
authorAlexander Clouter <alex@digriz.org.uk>
Sat, 8 Jan 2011 11:55:25 +0000 (11:55 +0000)
committerNicolas Pitre <nico@fluxnic.net>
Thu, 3 Mar 2011 20:53:34 +0000 (15:53 -0500)
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

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
arch/arm/mach-orion5x/ts78xx-setup.c

index c1c1cd0..89682e1 100644 (file)
@@ -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,
        },
 };