[Intel-gfx] [PATCH] drm/i915: disable PSR by default on HSW/BDW

[Jani Nikula]

On Tue, 13 Dec 2016, Paulo Zanoni <paulo.r.zanoni at intel.com> wrote:
> We've been ignoring the poor bugzilla reporters that say PSR causes
> system lockups and all other sorts of problems. The earliest bug
> report is from April, so I think we can use the "revert the offending
> commit if no fixes are presented within 8 months" rule here.

Ugh. Should be more like 2 weeks or so. We suck. :(

Acked-by: Jani Nikula <jani.nikula at intel.com>

PS. You're using a version of git that screws up # comments at the end
of Cc: lines, so I presume this didn't make it to stable list. It's
enough to have the Cc: in the commit when it gets applied though.

>
> Fixes: 9b58e352b463 ("drm/i915: Enable PSR by default on Haswell and Broadwell.")
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97602
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97515
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96736
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96704
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96569
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95176
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94985
> Cc: <stable at vger.kernel.org> # v4.6+
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Jim Bride <jim.bride at linux.intel.com>
> Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_psr.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
> index d5f8d03..6aca8ff 100644
> --- a/drivers/gpu/drm/i915/intel_psr.c
> +++ b/drivers/gpu/drm/i915/intel_psr.c
> @@ -823,13 +823,9 @@ void intel_psr_init(struct drm_i915_private *dev_priv)
>  	dev_priv->psr_mmio_base = IS_HASWELL(dev_priv) ?
>  		HSW_EDP_PSR_BASE : BDW_EDP_PSR_BASE;
>  
> -	/* Per platform default */
> -	if (i915.enable_psr == -1) {
> -		if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
> -			i915.enable_psr = 1;
> -		else
> -			i915.enable_psr = 0;
> -	}
> +	/* Per platform default: all disabled. */
> +	if (i915.enable_psr == -1)
> +		i915.enable_psr = 0;
>  
>  	/* Set link_standby x link_off defaults */
>  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))

-- 
Jani Nikula, Intel Open Source Technology Center