The functions to detect the state of the ready / busy signal is already available but only used in the SPL case. Lets use it always, also for the main U-Boot. As all boards should have this HW connection.
Testing on Siemens Draco (am335x) showed a small perfomance gain by using this ready pin to detect the NAND chip state. Here the values tested on Draco with Hynix 4GBit NAND:
Without NAND ready pin:
U-Boot# time nand read 80400000 0 400000
NAND read: device 0 offset 0x0, size 0x400000 4194304 bytes read: OK
time: 2.947 seconds, 2947 ticks
With NAND ready pin:
U-Boot# time nand read 80400000 0 400000
NAND read: device 0 offset 0x0, size 0x400000 4194304 bytes read: OK
time: 2.795 seconds, 2795 ticks
So an increase of approx. 5%.
Signed-off-by: Stefan Roese sr@denx.de Cc: Tom Rini trini@ti.com Cc: Scott Wood scottwood@freescale.com Cc: Roger Meier r.meier@siemens.com Cc: Samuel Egli samuel.egli@siemens.com --- v2: - Only one patch now in this series - Drop the new define and make this change unconditional
drivers/mtd/nand/omap_gpmc.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/mtd/nand/omap_gpmc.c b/drivers/mtd/nand/omap_gpmc.c index 40d6705..93829a4 100644 --- a/drivers/mtd/nand/omap_gpmc.c +++ b/drivers/mtd/nand/omap_gpmc.c @@ -73,14 +73,11 @@ static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd, writeb(cmd, this->IO_ADDR_W); }
-#ifdef CONFIG_SPL_BUILD /* Check wait pin as dev ready indicator */ -static int omap_spl_dev_ready(struct mtd_info *mtd) +static int omap_dev_ready(struct mtd_info *mtd) { return gpmc_cfg->status & (1 << 8); } -#endif -
/* * gen_true_ecc - This function will generate true ECC value, which @@ -887,7 +884,9 @@ int board_nand_init(struct nand_chip *nand) nand->read_buf = nand_read_buf16; else nand->read_buf = nand_read_buf; - nand->dev_ready = omap_spl_dev_ready; #endif + + nand->dev_ready = omap_dev_ready; + return 0; }