[PATCH] drm/i915: Don't check modeset state in the hw state force restore path

Ander Conselvan de Oliveira
2015-06-01T12:41:21Z

Since the force restore logic will restore the CRTCs state one at a
time, it is possible that the state will be inconsistent until the whole
operation finishes. A call to intel_modeset_check_state() is done once
it's over, so don't check the state multiple times in between. This
regression was introduced in:

commit 7f27126ea3db6ade886f18fd39caf0ff0cd1d37f
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Wed Nov 5 14:26:06 2014 -0800

drm/i915: factor out compute_config from __intel_set_mode v3

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=94431
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
---

Hi,

This patch applies on top of nightly, but it is only relevant without
Maarten's "drm/i915: Convert to atomic, part 2" series, because of the
changes to the hw state read out and force restore logic.

The regression exists since 3.19.

---
drivers/gpu/drm/i915/intel_display.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 16e159d..24fb7ce 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -87,7 +87,8 @@ static void ironlake_pch_clock_get(struct intel_crtc *crtc,
struct intel_crtc_state *pipe_config);

static int intel_set_mode(struct drm_crtc *crtc,
- struct drm_atomic_state *state);
+ struct drm_atomic_state *state,
+ bool check);
static int intel_framebuffer_init(struct drm_device *dev,
struct intel_framebuffer *ifb,
struct drm_mode_fb_cmd2 *mode_cmd,
@@ -10282,7 +10283,7 @@ retry:

drm_mode_copy(&crtc_state->base.mode, mode);

- if (intel_set_mode(crtc, state)) {
+ if (intel_set_mode(crtc, state, true)) {
DRM_DEBUG_KMS("failed to set mode on load-detect pipe\n");
if (old->release_fb)
old->release_fb->funcs->destroy(old->release_fb);
@@ -10356,7 +10357,7 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
if (ret)
goto fail;

- ret = intel_set_mode(crtc, state);
+ ret = intel_set_mode(crtc, state, true);
if (ret)
goto fail;

@@ -12832,20 +12833,22 @@ static int __intel_set_mode(struct drm_crtc *modeset_crtc,
}

static int intel_set_mode_with_config(struct drm_crtc *crtc,
- struct intel_crtc_state *pipe_config)
+ struct intel_crtc_state *pipe_config,
+ bool check)
{
int ret;

ret = __intel_set_mode(crtc, pipe_config);

- if (ret == 0)
+ if (ret == 0 && check)
intel_modeset_check_state(crtc->dev);

return ret;
}

static int intel_set_mode(struct drm_crtc *crtc,
- struct drm_atomic_state *state)
+ struct drm_atomic_state *state,
+ bool check)
{
struct intel_crtc_state *pipe_config;
int ret = 0;
@@ -12856,7 +12859,7 @@ static int intel_set_mode(struct drm_crtc *crtc,
goto out;
}

- ret = intel_set_mode_with_config(crtc, pipe_config);
+ ret = intel_set_mode_with_config(crtc, pipe_config, check);
if (ret)
goto out;

@@ -12933,7 +12936,7 @@ void intel_crtc_restore_mode(struct drm_crtc *crtc)
intel_modeset_setup_plane_state(state, crtc, &crtc->mode,
crtc->primary->fb, crtc->x, crtc->y);

- ret = intel_set_mode(crtc, state);
+ ret = intel_set_mode(crtc, state, false);
if (ret)
drm_atomic_state_free(state);
}
@@ -13133,7 +13136,7 @@ static int intel_crtc_set_config(struct drm_mode_set *set)

primary_plane_was_visible = primary_plane_visible(set->crtc);

- ret = intel_set_mode_with_config(set->crtc, pipe_config);
+ ret = intel_set_mode_with_config(set->crtc, pipe_config, true);

if (ret == 0 &&
pipe_config->base.enable &&
--
2.1.0