On Wed, Aug 14, 2013 at 02:40:37PM -0300, Paulo Zanoni wrote:
> From: Paulo Zanoni <paulo.r.zan...@intel.com>
>
> Our driver initialization doesn't seem to be ready to load when the
> power well is disabled: we hit a few "Unclaimed register" messages. So
> do just like we already do for the suspend/resume path: enable the
> power well before unloading.
>
> At some point we'll want to be able to survive suspend/resume and
> load/unload with the power well disabled, but for now let's just fix
> the regression.
>
> Regression introduced by the following commit:
>
> commit bf51d5e2cda5d36d98e4b46ac7fca9461e512c41
> Author: Paulo Zanoni <paulo.r.zan...@intel.com>
> Date: Wed Jul 3 17:12:13 2013 -0300
> drm/i915: switch disable_power_well default value to 1
>
> Bug can be reproduced by running the "module_reload" script from
> intel-gpu-tools.
>
> Cc: sta...@vger.kernel.org
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67813
> Signed-off-by: Paulo Zanoni <paulo.r.zan...@intel.com>
Reviewed-by: Damien Lespiau <damien.lesp...@intel.com>
--
Damien
> ---
> drivers/gpu/drm/i915/i915_dma.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
>
> QA (the bug reporter) still didn't confirm this patch fixes the bug, but I can
> reproduce it and I can confirm it fixes the problem at least on my machine.
>
> Also please notice we have other problems that happen when we run
> module_reload
> (e.g., gpu hang, no backlight, lockdep error message, eventual oops), this
> patch
> fixes only the "Unclaimed register" errors.
>
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index b30404d..d2dc02b 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -1688,8 +1688,13 @@ int i915_driver_unload(struct drm_device *dev)
>
> intel_gpu_ips_teardown();
>
> - if (HAS_POWER_WELL(dev))
> + if (HAS_POWER_WELL(dev)) {
> + /* The i915.ko module is still not prepared to be loaded when
> + * the power well is not enabled, so just enable it in case
> + * we're going to unload/reload. */
> + intel_set_power_well(dev, true);
> i915_remove_power_well(dev);
> + }
>
> i915_teardown_sysfs(dev);
>
> --
> 1.8.1.2
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
