From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= <ville.syrjala@linux.intel.com>
Subject: Re: [PATCH] drm/i915: vlv: reserve the GT power context
 only once during driver init
Date: Tue, 1 Apr 2014 20:11:22 +0300
Message-ID: <20140401171122.GJ21652@intel.com>
References: <1396267844-9235-1-git-send-email-imre.deak@intel.com>
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To: Imre Deak <imre.deak@intel.com>
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On Mon, Mar 31, 2014 at 03:10:44PM +0300, Imre Deak wrote:
> Atm we reserve/allocate and free the power context during GT power
> enable/disable time. There is no need to do this, we can reserve/allocate
> the buffer once during driver loading and free it during driver cleanup.
> The re-reservation can also fail in case the driver previously manages to
> allocate something on the given fixed address.
> =

> The buffer isn't exepected to move even if allocated by the BIOS, for
> safety add an assert to check this assumption.
> =

> This also fixed a bug for Ville, where re-reserving the context failed
> during a GPU reset (I assume because something else got allocated on its
> fixed address).

I'm assuming it was the already existing pctx allocation that caused the
warning. We just call intel_enable_gt_powersave() again during GPU reset
w/o having called intel_disable_gt_powersave() anywhere. So no danger of
clobbering the pctx AFAICS, but getting a WARN on every GPU reset is
rather annoying.

> =

> Tested-by: Ville Syrj=E4l=E4 <ville.syrjala@linux.intel.com>
> Signed-off-by: Imre Deak <imre.deak@intel.com>

The patch looks good to me.

Reviewed-by: Ville Syrj=E4l=E4 <ville.syrjala@linux.intel.com>

<snip>

-- =

Ville Syrj=E4l=E4
Intel OTC