Greg KH wrote: > On Sat, Nov 18, 2017 at 05:08:20PM +0100, Rainer Fiebig wrote: >> Greg KH wrote: >>> On Sat, Nov 18, 2017 at 01:47:32PM +0100, Rainer Fiebig wrote: >>>> Hi! >>>> >>>> Hopefully the right addressee. >>>> >>>> Encountered two bad backports which cause screen-flicker. >>>> dmesg shows: >>>> >>>> ... >>>> [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun >>>> [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun >>>> [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun >>>> [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun >>>> ... >>>> >>>> CPU: Intel Core i3 (Clarkdale/Ironlake) >>>> >>>> The backports are: >>>> >>>> - diff --git a/drivers/gpu/drm/i915/intel_pm.c >>>> b/drivers/gpu/drm/i915/intel_pm.c >>>> index 49de476..277a802 100644 >>>> - diff --git a/drivers/gpu/drm/i915/intel_drv.h >>>> b/drivers/gpu/drm/i915/intel_drv.h >>>> index a19ec06..3ce9ba3 100644 >>>> >>>> After reversing them the flicker is gone, no more messages in dmesg. All >>>> else OK so far. >>> >>> So which commit was the one that caused the problem? I will be glad to >>> revert it. >>> >>> thanks, >>> >>> greg k-h >>> >>> >> >> I started by reverting the more complex one first ("index >> 49de476..277a802100644"). But the kernel wouldn't compile then. > > What git commit id is that? I don't see those ids in the 4.9-stable > tree. > >> So I also reverted "index a19ec06..3ce9ba3 100644". After that the >> kernel compiled just fine and the problems were gone (still are). > > Same here, what git commit id was this? > > thanks, > > greg k-h > OK, no mistake. IIRC, I took the patches (and the IDs) from the changelog for patch-4.9.62. I've attached both, so you can check yourself. I've also applied a freshly downloaded patch-4.9.62 to a freshly expanded 4.9 and re-compiled. The flicker is there. I haven't yet reverted the two patches but I'm confident that after having done so the flicker will be gone. If not I'll let you know. As a good news: 4.14 is *not* affected. So to me it seems those two patches are part of sort of a package and can not be backported alone. So long! Rainer Fiebig
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 49de476..277a802 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -27,6 +27,7 @@ #include <linux/cpufreq.h> #include <drm/drm_plane_helper.h> +#include <drm/drm_atomic_helper.h> #include "i915_drv.h" #include "intel_drv.h" #include "../../../platform/x86/intel_ips.h" @@ -2017,9 +2018,9 @@ static void ilk_compute_wm_level(const struct drm_i915_private *dev_priv, const struct intel_crtc *intel_crtc, int level, struct intel_crtc_state *cstate, - struct intel_plane_state *pristate, - struct intel_plane_state *sprstate, - struct intel_plane_state *curstate, + const struct intel_plane_state *pristate, + const struct intel_plane_state *sprstate, + const struct intel_plane_state *curstate, struct intel_wm_level *result) { uint16_t pri_latency = dev_priv->wm.pri_latency[level]; @@ -2341,28 +2342,24 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate) struct intel_pipe_wm *pipe_wm; struct drm_device *dev = state->dev; const struct drm_i915_private *dev_priv = to_i915(dev); - struct intel_plane *intel_plane; - struct intel_plane_state *pristate = NULL; - struct intel_plane_state *sprstate = NULL; - struct intel_plane_state *curstate = NULL; + struct drm_plane *plane; + const struct drm_plane_state *plane_state; + const struct intel_plane_state *pristate = NULL; + const struct intel_plane_state *sprstate = NULL; + const struct intel_plane_state *curstate = NULL; int level, max_level = ilk_wm_max_level(dev), usable_level; struct ilk_wm_maximums max; pipe_wm = &cstate->wm.ilk.optimal; - for_each_intel_plane_on_crtc(dev, intel_crtc, intel_plane) { - struct intel_plane_state *ps; + drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, &cstate->base) { + const struct intel_plane_state *ps = to_intel_plane_state(plane_state); - ps = intel_atomic_get_existing_plane_state(state, - intel_plane); - if (!ps) - continue; - - if (intel_plane->base.type == DRM_PLANE_TYPE_PRIMARY) + if (plane->type == DRM_PLANE_TYPE_PRIMARY) pristate = ps; - else if (intel_plane->base.type == DRM_PLANE_TYPE_OVERLAY) + else if (plane->type == DRM_PLANE_TYPE_OVERLAY) sprstate = ps; - else if (intel_plane->base.type == DRM_PLANE_TYPE_CURSOR) + else if (plane->type == DRM_PLANE_TYPE_CURSOR) curstate = ps; } @@ -2384,11 +2381,9 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate) if (pipe_wm->sprites_scaled) usable_level = 0; - ilk_compute_wm_level(dev_priv, intel_crtc, 0, cstate, - pristate, sprstate, curstate, &pipe_wm->raw_wm[0]); - memset(&pipe_wm->wm, 0, sizeof(pipe_wm->wm)); - pipe_wm->wm[0] = pipe_wm->raw_wm[0]; + ilk_compute_wm_level(dev_priv, intel_crtc, 0, cstate, + pristate, sprstate, curstate, &pipe_wm->wm[0]); if (IS_HASWELL(dev) || IS_BROADWELL(dev)) pipe_wm->linetime = hsw_compute_linetime_wm(cstate); @@ -2398,8 +2393,8 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate) ilk_compute_wm_reg_maximums(dev, 1, &max); - for (level = 1; level <= max_level; level++) { - struct intel_wm_level *wm = &pipe_wm->raw_wm[level]; + for (level = 1; level <= usable_level; level++) { + struct intel_wm_level *wm = &pipe_wm->wm[level]; ilk_compute_wm_level(dev_priv, intel_crtc, level, cstate, pristate, sprstate, curstate, wm); @@ -2409,13 +2404,10 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate) * register maximums since such watermarks are * always invalid. */ - if (level > usable_level) - continue; - - if (ilk_validate_wm_level(level, &max, wm)) - pipe_wm->wm[level] = *wm; - else - usable_level = level; + if (!ilk_validate_wm_level(level, &max, wm)) { + memset(wm, 0, sizeof(*wm)); + break; + } } return 0;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index a19ec06..3ce9ba3 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -457,7 +457,6 @@ struct intel_crtc_scaler_state { struct intel_pipe_wm { struct intel_wm_level wm[5]; - struct intel_wm_level raw_wm[5]; uint32_t linetime; bool fbc_wm_enabled; bool pipe_enabled;