[Intel-gfx] [PATCH] drm/i915: Kill sink_crc for good
Dhinakaran Pandiyan
dhinakaran.pandiyan at gmail.com
Thu Jul 5 21:11:45 UTC 2018
On Thursday, July 5, 2018 12:25:28 PM PDT Rodrigo Vivi wrote:
> It was originally introduced following the VESA spec in order to validate
> PSR.
>
> However we found so many issues around sink_crc that instead of helping PSR
> development it only brought another layer of trouble to the table.
>
> So, sink_crc has been a black whole for us in question of time, effort and
> hope.
>
> First of the problems is that HW statement is clear: "Do not attempt to use
> aux communication with PSR enabled". So the main reason behind sink_crc is
> already compromised.
>
> For a while we had hope on the aux-mutex could workaround this problem on
> SKL+ platforms, but that mutex was not reliable, not tested,
> and we shouldn't use according to HW engineers.
>
> Also, nor source, nor sink designed and implemented the sink_crc to be used
> like we are trying to use here.
>
> Well, the sink side of things is also apparently not prepared for this
> case. Each panel that we tried seemed to have a different behavior with same
> code and same source.
>
> So, for all the time we lost on trying to ducktape all these different
> issues I believe it is now time to move PSR to a more reliable validation.
> Maybe not a perfect one as we dreamed for this sink_crc, but at least more
> reliable.
>
Good riddance.
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
> drivers/gpu/drm/i915/i915_debugfs.c | 81 ------------------
> drivers/gpu/drm/i915/intel_dp.c | 123 ----------------------------
> drivers/gpu/drm/i915/intel_drv.h | 2 -
> 3 files changed, 206 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> b/drivers/gpu/drm/i915/i915_debugfs.c index f6142d78ede4..e8fa106a3655
> 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -2761,86 +2761,6 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_edp_psr_debug_fops,
> i915_edp_psr_debug_get, i915_edp_psr_debug_set,
> "%llu\n");
>
> -static int i915_sink_crc(struct seq_file *m, void *data)
> -{
> - struct drm_i915_private *dev_priv = node_to_i915(m->private);
> - struct drm_device *dev = &dev_priv->drm;
> - struct intel_connector *connector;
> - struct drm_connector_list_iter conn_iter;
> - struct intel_dp *intel_dp = NULL;
> - struct drm_modeset_acquire_ctx ctx;
> - int ret;
> - u8 crc[6];
> -
> - drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> -
> - drm_connector_list_iter_begin(dev, &conn_iter);
> -
> - for_each_intel_connector_iter(connector, &conn_iter) {
> - struct drm_crtc *crtc;
> - struct drm_connector_state *state;
> - struct intel_crtc_state *crtc_state;
> -
> - if (connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
> - continue;
> -
> -retry:
> - ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
> - if (ret)
> - goto err;
> -
> - state = connector->base.state;
> - if (!state->best_encoder)
> - continue;
> -
> - crtc = state->crtc;
> - ret = drm_modeset_lock(&crtc->mutex, &ctx);
> - if (ret)
> - goto err;
> -
> - crtc_state = to_intel_crtc_state(crtc->state);
> - if (!crtc_state->base.active)
> - continue;
> -
> - /*
> - * We need to wait for all crtc updates to complete, to make
> - * sure any pending modesets and plane updates are completed.
> - */
> - if (crtc_state->base.commit) {
> - ret =
> wait_for_completion_interruptible(&crtc_state->base.commit->hw_done); -
> - if (ret)
> - goto err;
> - }
> -
> - intel_dp = enc_to_intel_dp(state->best_encoder);
> -
> - ret = intel_dp_sink_crc(intel_dp, crtc_state, crc);
> - if (ret)
> - goto err;
> -
> - seq_printf(m, "%02x%02x%02x%02x%02x%02x\n",
> - crc[0], crc[1], crc[2],
> - crc[3], crc[4], crc[5]);
> - goto out;
> -
> -err:
> - if (ret == -EDEADLK) {
> - ret = drm_modeset_backoff(&ctx);
> - if (!ret)
> - goto retry;
> - }
> - goto out;
> - }
> - ret = -ENODEV;
> -out:
> - drm_connector_list_iter_end(&conn_iter);
> - drm_modeset_drop_locks(&ctx);
> - drm_modeset_acquire_fini(&ctx);
> -
> - return ret;
> -}
> -
> static int i915_energy_uJ(struct seq_file *m, void *data)
> {
> struct drm_i915_private *dev_priv = node_to_i915(m->private);
> @@ -4784,7 +4704,6 @@ static const struct drm_info_list i915_debugfs_list[]
> = { {"i915_ppgtt_info", i915_ppgtt_info, 0},
> {"i915_llc", i915_llc, 0},
> {"i915_edp_psr_status", i915_edp_psr_status, 0},
> - {"i915_sink_crc_eDP1", i915_sink_crc, 0},
> {"i915_energy_uJ", i915_energy_uJ, 0},
> {"i915_runtime_pm_status", i915_runtime_pm_status, 0},
> {"i915_power_domain_info", i915_power_domain_info, 0},
> diff --git a/drivers/gpu/drm/i915/intel_dp.c
> b/drivers/gpu/drm/i915/intel_dp.c index 5be07e1d816d..efdd4b408d51 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -3905,129 +3905,6 @@ intel_dp_configure_mst(struct intel_dp *intel_dp)
> intel_dp->is_mst);
> }
>
> -static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp,
> - struct intel_crtc_state *crtc_state, bool disable_wa)
> -{
> - struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> - struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> - struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> - u8 buf;
> - int ret = 0;
> - int count = 0;
> - int attempts = 10;
> -
> - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) {
> - DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> - ret = -EIO;
> - goto out;
> - }
> -
> - if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> - buf & ~DP_TEST_SINK_START) < 0) {
> - DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> - ret = -EIO;
> - goto out;
> - }
> -
> - do {
> - intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> -
> - if (drm_dp_dpcd_readb(&intel_dp->aux,
> - DP_TEST_SINK_MISC, &buf) < 0) {
> - ret = -EIO;
> - goto out;
> - }
> - count = buf & DP_TEST_COUNT_MASK;
> - } while (--attempts && count);
> -
> - if (attempts == 0) {
> - DRM_DEBUG_KMS("TIMEOUT: Sink CRC counter is not zeroed after
calculation
> is stopped\n"); - ret = -ETIMEDOUT;
> - }
> -
> - out:
> - if (disable_wa)
> - hsw_enable_ips(crtc_state);
> - return ret;
> -}
> -
> -static int intel_dp_sink_crc_start(struct intel_dp *intel_dp,
> - struct intel_crtc_state *crtc_state)
> -{
> - struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> - struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> - struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> - u8 buf;
> - int ret;
> -
> - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
> - return -EIO;
> -
> - if (!(buf & DP_TEST_CRC_SUPPORTED))
> - return -ENOTTY;
> -
> - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0)
> - return -EIO;
> -
> - if (buf & DP_TEST_SINK_START) {
> - ret = intel_dp_sink_crc_stop(intel_dp, crtc_state, false);
> - if (ret)
> - return ret;
> - }
> -
> - hsw_disable_ips(crtc_state);
> -
> - if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> - buf | DP_TEST_SINK_START) < 0) {
> - hsw_enable_ips(crtc_state);
> - return -EIO;
> - }
> -
> - intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> - return 0;
> -}
> -
> -int intel_dp_sink_crc(struct intel_dp *intel_dp, struct intel_crtc_state
> *crtc_state, u8 *crc) -{
> - struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> - struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> - struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> - u8 buf;
> - int count, ret;
> - int attempts = 6;
> -
> - ret = intel_dp_sink_crc_start(intel_dp, crtc_state);
> - if (ret)
> - return ret;
> -
> - do {
> - intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> -
> - if (drm_dp_dpcd_readb(&intel_dp->aux,
> - DP_TEST_SINK_MISC, &buf) < 0) {
> - ret = -EIO;
> - goto stop;
> - }
> - count = buf & DP_TEST_COUNT_MASK;
> -
> - } while (--attempts && count == 0);
> -
> - if (attempts == 0) {
> - DRM_ERROR("Panel is unable to calculate any CRC after 6 vblanks\n");
> - ret = -ETIMEDOUT;
> - goto stop;
> - }
> -
> - if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) {
> - ret = -EIO;
> - goto stop;
> - }
> -
> -stop:
> - intel_dp_sink_crc_stop(intel_dp, crtc_state, true);
> - return ret;
> -}
> -
> static bool
> intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector)
> {
> diff --git a/drivers/gpu/drm/i915/intel_drv.h
> b/drivers/gpu/drm/i915/intel_drv.h index e09b42d91d1e..8e6ee2fe66e4 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1665,8 +1665,6 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int
> mode); void intel_dp_encoder_reset(struct drm_encoder *encoder);
> void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder);
> void intel_dp_encoder_destroy(struct drm_encoder *encoder);
> -int intel_dp_sink_crc(struct intel_dp *intel_dp,
> - struct intel_crtc_state *crtc_state, u8 *crc);
> bool intel_dp_compute_config(struct intel_encoder *encoder,
> struct intel_crtc_state *pipe_config,
> struct drm_connector_state *conn_state);
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