From e40210cca98068835acd5a4fe760bf96b3a1aa48 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Fri, 13 Sep 2013 10:55:10 -0400 Subject: [PATCH] drm/radeon/dpm/rs780: don't enable sclk scaling if not required MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If the low and high sclks are the same, there is no need to enable sclk scaling. This causes display stability issues on certain boards. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=60857 Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Reviewed-by: Christian König --- drivers/gpu/drm/radeon/rs780_dpm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/radeon/rs780_dpm.c b/drivers/gpu/drm/radeon/rs780_dpm.c index 31487ce294cf..eb336bf5a54e 100644 --- a/drivers/gpu/drm/radeon/rs780_dpm.c +++ b/drivers/gpu/drm/radeon/rs780_dpm.c @@ -499,6 +499,9 @@ static void rs780_activate_engine_clk_scaling(struct radeon_device *rdev, (new_state->sclk_low == old_state->sclk_low)) return; + if (new_state->sclk_high == new_state->sclk_low) + return; + rs780_clk_scaling_enable(rdev, true); }