drm/radeon/kms: use udelay for short delays

For usec delays use udelay instead of scheduling, this should
allow reclocking to happen faster. This also was the cause
of reported 33s delays at bootup on certain systems.

fixes: freedesktop.org bug 25506

Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/radeon/atom.c b/drivers/gpu/drm/radeon/atom.c
index 2a3df55..7f152f6 100644 (file)
--- a/drivers/gpu/drm/radeon/atom.c
+++ b/drivers/gpu/drm/radeon/atom.c
@@ -643,7 +643,7 @@ static void atom_op_delay(atom_exec_context *ctx, int *ptr, int arg)
        uint8_t count = U8((*ptr)++);
        SDEBUG("   count: %d\n", count);
        if (arg == ATOM_UNIT_MICROSEC)
-               schedule_timeout_uninterruptible(usecs_to_jiffies(count));
+               udelay(count);
        else
                schedule_timeout_uninterruptible(msecs_to_jiffies(count));
 }