From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rodrigo Vivi , Kenneth Graunke , Art Runyan , "Kumar, Kiran S" , Ben Widawsky , Jani Nikula Subject: [PATCH 3.13 04/46] drm/i915: Fix PSR programming Date: Fri, 28 Mar 2014 10:31:48 -0700 Message-Id: <20140328173135.233702392@linuxfoundation.org> In-Reply-To: <20140328173134.630198216@linuxfoundation.org> References: <20140328173134.630198216@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Widawsky commit 24bd9bf54d45d28089251cdf62bf14323d1aa827 upstream. | has a higher precedence than ?. Therefore, the calculation doesn't do at all what you would expect. Thanks to Ken for convincing me that this was indeed the issue. Send me back to C programmer school, please. I'm sort of surprised PSR was continuing to work for people. It should be broken IMO (and it was broken for me, but I had assumed it never worked). Regression from: commit ed8546ac1f99b850879f07b1e9b06b42fb0a36d9 Author: Ben Widawsky Date: Mon Nov 4 22:45:05 2013 -0800 drm/i915/bdw: Support eDP PSR Cc: Rodrigo Vivi Cc: Kenneth Graunke Cc: Art Runyan Reported-by: "Kumar, Kiran S" Signed-off-by: Ben Widawsky Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1634,7 +1634,7 @@ static void intel_edp_psr_enable_source( val |= EDP_PSR_LINK_DISABLE; I915_WRITE(EDP_PSR_CTL(dev), val | - IS_BROADWELL(dev) ? 0 : link_entry_time | + (IS_BROADWELL(dev) ? 0 : link_entry_time) | max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT | idle_frames << EDP_PSR_IDLE_FRAME_SHIFT | EDP_PSR_ENABLE);