From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757720AbdKOLIQ (ORCPT ); Wed, 15 Nov 2017 06:08:16 -0500 Received: from mga02.intel.com ([134.134.136.20]:17516 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755467AbdKOLIJ (ORCPT ); Wed, 15 Nov 2017 06:08:09 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,398,1505804400"; d="scan'208";a="1244393314" Date: Wed, 15 Nov 2017 13:08:05 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: alexander.levin@verizon.com Cc: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH AUTOSEL for 4.9 36/56] drm/i915: Fix the level 0 max_wm hack on VLV/CHV Message-ID: <20171115110805.GX10981@intel.com> References: <20171115024521.5884-1-alexander.levin@verizon.com> <20171115024521.5884-36-alexander.levin@verizon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20171115024521.5884-36-alexander.levin@verizon.com> User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 15, 2017 at 02:45:43AM +0000, alexander.levin@verizon.com wrote: > From: Ville Syrjälä > > [ Upstream commit 1be4d3793d5a93daddcd9be657c429b38ad750a3 ] > > The watermark should never exceed the FIFO size, so we need to > check against the current FIFO size instead of the theoretical > maximum when we clamp the level 0 watermark. > > Signed-off-by: Ville Syrjälä > Link: http://patchwork.freedesktop.org/patch/msgid/1480354637-14209-4-git-send-email-ville.syrjala@linux.intel.com > Reviewed-by: Maarten Lankhorst > Signed-off-by: Sasha Levin Why are these patches being proposed for stable? They're not straight up fixes for known issues, and there's always a chance that something will break. Who is doing the qa on this? > --- > drivers/gpu/drm/i915/intel_pm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c > index ad5649259e6a..12bc608833cf 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -1129,13 +1129,13 @@ static void vlv_compute_wm(struct intel_crtc *crtc) > /* normal watermarks */ > for (level = 0; level < wm_state->num_levels; level++) { > int wm = vlv_compute_wm_level(plane, crtc, state, level); > - int max_wm = plane->base.type == DRM_PLANE_TYPE_CURSOR ? 63 : 511; > + int max_wm = plane->wm.fifo_size; > > /* hack */ > if (WARN_ON(level == 0 && wm > max_wm)) > wm = max_wm; > > - if (wm > plane->wm.fifo_size) > + if (wm > max_wm) > break; > > switch (plane->base.type) { > -- > 2.11.0 -- Ville Syrjälä Intel OTC