diff options
| author | Russell King - ARM Linux <linux@arm.linux.org.uk> | 2011-01-03 23:36:29 +0100 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2011-01-05 04:16:11 +0100 |
| commit | 19386b3234fdbe4d33492574d83e63a8dace18d3 (patch) | |
| tree | 0d362485f1dd6fc360f3b707ab2a97ff8b3f2d17 /drivers/dma | |
| parent | ARM: PL08x: consolidate physical channel release code (diff) | |
| download | linux-19386b3234fdbe4d33492574d83e63a8dace18d3.tar.xz linux-19386b3234fdbe4d33492574d83e63a8dace18d3.zip | |
ARM: PL08x: ensure loops use cpu_relax()
Tight loops should use cpu_relax() to allow CPUs to reduce power
consumption while waiting for events.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/amba-pl08x.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index e8967ff44fc2..78c84b3f903d 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -191,7 +191,7 @@ static void pl08x_set_cregs(struct pl08x_driver_data *pl08x, { /* Wait for channel inactive */ while (pl08x_phy_channel_busy(ch)) - ; + cpu_relax(); dev_vdbg(&pl08x->adev->dev, "WRITE channel %d: csrc=0x%08x, cdst=0x%08x, " @@ -255,7 +255,7 @@ static void pl08x_enable_phy_chan(struct pl08x_driver_data *pl08x, * Do not access config register until channel shows as disabled */ while (readl(pl08x->base + PL080_EN_CHAN) & (1 << ch->id)) - ; + cpu_relax(); /* * Do not access config register until channel shows as inactive @@ -288,7 +288,7 @@ static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch) /* Wait for channel inactive */ while (pl08x_phy_channel_busy(ch)) - ; + cpu_relax(); } static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch) |