From b5992fac88f8068f4f1af1de2e76889465e45693 Mon Sep 17 00:00:00 2001 From: Amit Virdi Date: Mon, 7 May 2012 13:00:29 +0530 Subject: st_smi: Change timeout loop implementation There are two problems in the current timeout loop implementation: 1. In case initial test failing, there will always be a delay of 1 ms 2. The delay duration is not tunable The new implementation addresses both these limitations. Signed-off-by: Amit Virdi Signed-off-by: Stefan Roese --- drivers/mtd/st_smi.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/mtd/st_smi.c b/drivers/mtd/st_smi.c index 5378b57b1b..75ae9aa606 100644 --- a/drivers/mtd/st_smi.c +++ b/drivers/mtd/st_smi.c @@ -102,11 +102,15 @@ static struct flash_device flash_devices[] = { */ static int smi_wait_xfer_finish(int timeout) { - do { + ulong start = get_timer(0); + + while (get_timer(start) < timeout) { if (readl(&smicntl->smi_sr) & TFF) return 0; - udelay(1000); - } while (timeout--); + + /* Try after 10 ms */ + udelay(10); + }; return -1; } @@ -219,16 +223,17 @@ static int smi_read_sr(int bank) static int smi_wait_till_ready(int bank, int timeout) { int sr; + ulong start = get_timer(0); /* One chip guarantees max 5 msec wait here after page writes, but potentially three seconds (!) after page erase. */ - do { + while (get_timer(start) < timeout) { sr = smi_read_sr(bank); if ((sr >= 0) && (!(sr & WIP_BIT))) return 0; - /* Try again after 1m-sec */ - udelay(1000); + /* Try again after 10 usec */ + udelay(10); } while (timeout--); printf("SMI controller is still in wait, timeout=%d\n", timeout); @@ -245,6 +250,7 @@ static int smi_wait_till_ready(int bank, int timeout) static int smi_write_enable(int bank) { u32 ctrlreg1; + u32 start; int timeout = WMODE_TOUT; int sr; @@ -263,14 +269,15 @@ static int smi_write_enable(int bank) /* Restore the CTRL REG1 state */ writel(ctrlreg1, &smicntl->smi_cr1); - do { + start = get_timer(0); + while (get_timer(start) < timeout) { sr = smi_read_sr(bank); if ((sr >= 0) && (sr & (1 << (bank + WM_SHIFT)))) return 0; - /* Try again after 1m-sec */ - udelay(1000); - } while (timeout--); + /* Try again after 10 usec */ + udelay(10); + }; return -1; } -- cgit v1.2.3