This is a note to let you know that I've just added the patch titled drm/i915: Don't leave old junk in ilk active watermarks on readout to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-i915-don-t-leave-old-junk-in-ilk-active-watermarks-on-readout.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 7045c3689f148a0c95f42bae8ef3eb2829ac7de9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@xxxxxxxxxxxxxxx> Date: Fri, 13 May 2016 17:55:17 +0300 Subject: drm/i915: Don't leave old junk in ilk active watermarks on readout MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> commit 7045c3689f148a0c95f42bae8ef3eb2829ac7de9 upstream. When we read out the watermark state from the hardware we're supposed to transfer that into the active watermarks, but currently we fail to any part of the active watermarks that isn't explicitly written. Let's clear it all upfront. Looks like this has been like this since the beginning, when I added the readout. No idea why I didn't clear it up. Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> Fixes: 243e6a44b9ca ("drm/i915: Init HSW watermark tracking in intel_modeset_setup_hw_state()") Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx> Signed-off-by: Matt Roper <matthew.d.roper@xxxxxxxxx> Link: http://patchwork.freedesktop.org/patch/msgid/1463151318-14719-2-git-send-email-ville.syrjala@xxxxxxxxxxxxxxx (cherry picked from commit 15606534bf0a65d8a74a90fd57b8712d147dbca6) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_pm.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3880,6 +3880,8 @@ static void ilk_pipe_wm_get_hw_state(str if (IS_HASWELL(dev) || IS_BROADWELL(dev)) hw->wm_linetime[pipe] = I915_READ(PIPE_WM_LINETIME(pipe)); + memset(active, 0, sizeof(*active)); + active->pipe_enabled = intel_crtc->active; if (active->pipe_enabled) { Patches currently in stable-queue which might be from ville.syrjala@xxxxxxxxxxxxxxx are queue-4.4/mfd-intel_soc_pmic_core-terminate-panel-control-gpio-lookup-table-correctly.patch queue-4.4/drm-i915-don-t-leave-old-junk-in-ilk-active-watermarks-on-readout.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html