Hi
2013/3/7 Damien Lespiau <damien.lespiau at intel.com>:
> In the case where the hardware has been wrongly programmed and the EDP
> TRANS_DDI_FUNC_CTL register has a bogus value in its EDP Input field, we
> were using the pipe variable uninitialized.
>
> In this case, shutdown the transcoder. It will be programmed correctly
> the next time we try to enabled eDP.
>
> Signed-off-by: Damien Lespiau <damien.lespiau at intel.com>
> ---
> drivers/gpu/drm/i915/intel_display.c | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 502cb28..875baf1 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9107,6 +9107,13 @@ void intel_modeset_setup_hw_state(struct drm_device *dev,
> case TRANS_DDI_EDP_INPUT_C_ONOFF:
> pipe = PIPE_C;
> break;
> + default:
> + /* A bogus value has been programmed, disable
> + * the transcoder */
> + WARN(1, "Bogus eDP source %08x\n", tmp);
> + intel_ddi_disable_transcoder_func(dev_priv,
> + TRANSCODER_EDP);
I imagine this patch is a result of checking some code analyzer and
not real hardware, so we didn't really test this code on real
hardware, right? The WARN is definitely a must-have, but I kinda fear
this "disable" code since we can easily freeze the machine if we get
the mode set sequence wrong. Anyway, if the hardware is programmed in
an inconsistent way I don't really think there's a "right way" to
disable it, so:
Reviewed-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
But we need to watch out in case users start reporting about machines
that freeze during boot.
> + goto setup_pipes;
> }
>
> crtc = to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);
> @@ -9117,6 +9124,7 @@ void intel_modeset_setup_hw_state(struct drm_device *dev,
> }
> }
>
> +setup_pipes:
> for_each_pipe(pipe) {
> crtc = to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);
>
> --
> 1.7.7.5
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
--
Paulo Zanoni
