From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [Intel-gfx] [PATCH] [v3] drm/i915/bdw: Only use 2g GGTT for 32b platforms Date: Tue, 13 May 2014 10:41:58 +0300 Message-ID: <87oaz22khl.fsf@intel.com> References: <1399438739-14802-1-git-send-email-benjamin.widawsky@intel.com> <1399515479-18263-1-git-send-email-benjamin.widawsky@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <1399515479-18263-1-git-send-email-benjamin.widawsky@intel.com> Sender: stable-owner@vger.kernel.org To: Intel GFX Cc: Ben Widawsky , stable@vger.kernel.org, Ben Widawsky List-Id: intel-gfx@lists.freedesktop.org On Thu, 08 May 2014, Ben Widawsky wrote: > Daniel requested in the bug that I use a 3GB fallback size. Since this > is not in the spec as a valid size, I decided against it. We could > potentially add a patch to bump it to 3GB on top of this one. > > This probably should be CC: stable - but I'll let the powers that be > decide that one. > > Regression from a revert of the revert: > commit 7907f45bf9f67a1c5e5d4ae05bab428d7c2f43b2 > Author: Ben Widawsky > Date: Wed Feb 19 22:05:46 2014 -0800 > > Revert "drm/i915/bdw: Limit GTT to 2GB" > > v2: Change ifdef to 32b, instead of ifndef > update comment > > v3. Update comment to not wrap (Daniel). > Update commit message > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76619 > Cc: stable@vger.kernel.org > Reviewed-by: Daniel Vetter > Signed-off-by: Ben Widawsky > --- > drivers/gpu/drm/i915/i915_gem_gtt.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c > index 4d87bf2..8d6d531 100644 > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c > @@ -2640,6 +2640,13 @@ static inline unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl) > bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK; > if (bdw_gmch_ctl) > bdw_gmch_ctl = 1 << bdw_gmch_ctl; > + > +#ifdef CONFIG_32BIT There's no such config for x86. There's CONFIG_X86_32 though. Which I think matches the original approach of #ifndef CONFIG_64BIT in the referenced bug. However, "with this patch only, the system still hung while booting." [1]. I want a new patch with Tested-by on it. BR, Jani. [1] https://bugs.freedesktop.org/show_bug.cgi?id=76619#c16 > + /* Limit 32B platforms to a 2GB GGTT: 4 << 20 / pte size * PAGE_SIZE */ > + if (bdw_gmch_ctl > 4) > + bdw_gmch_ctl = 4; > +#endif > + > return bdw_gmch_ctl << 20; > } > > -- > 1.9.2 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center