mtd: fsl-quadspi: improve read performance by increase AHB transfer size

Set AHB transfer size to 1K which improved the read performance.

Add ahb_buf_size field in fsl_qspi_devtype_data to denote the size for
different SoC.

Before:

root@imx6qdlsolo:~# dd if=/dev/mtd1 of=/dev/null bs=1M count=16
16+0 records in
16+0 records out
16777216 bytes (17 MB) copied, 0.472183 s, 25.1 MB/s

After:

root@imx6qdlsolo:~# dd if=/dev/mtd1 of=/dev/null bs=1M count=16
16+0 records in
16+0 records out
16777216 bytes (17 MB) copied, 0.369439 s, 29.5 MB/s

Signed-off-by: Allen Xu <b45815@freescale.com>
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Frank Li <Frank.Li@freescale.com>
Acked-by: Huang Shijie <shijie.huang@intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Allen Xu 2015-01-14 00:28:56 +08:00 committed by Brian Norris
parent b1ab474fda
commit 4e898ce7d9

View File

@ -57,7 +57,9 @@
#define QUADSPI_BUF3CR 0x1c
#define QUADSPI_BUF3CR_ALLMST_SHIFT 31
#define QUADSPI_BUF3CR_ALLMST (1 << QUADSPI_BUF3CR_ALLMST_SHIFT)
#define QUADSPI_BUF3CR_ALLMST_MASK (1 << QUADSPI_BUF3CR_ALLMST_SHIFT)
#define QUADSPI_BUF3CR_ADATSZ_SHIFT 8
#define QUADSPI_BUF3CR_ADATSZ_MASK (0xFF << QUADSPI_BUF3CR_ADATSZ_SHIFT)
#define QUADSPI_BFGENCR 0x20
#define QUADSPI_BFGENCR_PAR_EN_SHIFT 16
@ -198,18 +200,21 @@ struct fsl_qspi_devtype_data {
enum fsl_qspi_devtype devtype;
int rxfifo;
int txfifo;
int ahb_buf_size;
};
static struct fsl_qspi_devtype_data vybrid_data = {
.devtype = FSL_QUADSPI_VYBRID,
.rxfifo = 128,
.txfifo = 64
.txfifo = 64,
.ahb_buf_size = 1024
};
static struct fsl_qspi_devtype_data imx6sx_data = {
.devtype = FSL_QUADSPI_IMX6SX,
.rxfifo = 128,
.txfifo = 512
.txfifo = 512,
.ahb_buf_size = 1024
};
#define FSL_QSPI_MAX_CHIP 4
@ -584,7 +589,12 @@ static void fsl_qspi_init_abh_read(struct fsl_qspi *q)
writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF0CR);
writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF1CR);
writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF2CR);
writel(QUADSPI_BUF3CR_ALLMST, base + QUADSPI_BUF3CR);
/*
* Set ADATSZ with the maximum AHB buffer size to improve the
* read performance.
*/
writel(QUADSPI_BUF3CR_ALLMST_MASK | ((q->devtype_data->ahb_buf_size / 8)
<< QUADSPI_BUF3CR_ADATSZ_SHIFT), base + QUADSPI_BUF3CR);
/* We only use the buffer3 */
writel(0, base + QUADSPI_BUF0IND);