>-----Original Message----- >From: Intel-gfx [mailto:intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of >Daniele Ceraolo Spurio >Sent: Thursday, December 22, 2016 10:45 AM >To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx >Subject: Re: [PATCH] drm/i915/guc: Reserve the upper end of the >Global GTT for the GuC > > >On 22/12/16 08:38, Arkadiusz Hiler wrote: >> On Thu, Dec 22, 2016 at 03:18:08PM +0000, Chris Wilson wrote: >>> On Thu, Dec 22, 2016 at 03:53:15PM +0100, Arkadiusz Hiler wrote: >>>> On Wed, Dec 21, 2016 at 07:35:04PM +0100, Srivatsa, Anusha wrote: >>>>> With enable_guc_loading=2 and enable_guc_submission=0 I get HuC >>>>> authentication failure and with enable_guc_loading and >>>>> enable_guc_submisssion both set to 2 the device does not show any >>>>> display. >>>> >>>> Sadly "the fix" fixes the issues we had with the loading - we can >>>> load GuC but... >>>> >>>> GuC Actions (INTEL_GUC_ACTION*, and intel_guc_send()) seem to care >>>> about kernel context pinned location as well (not directly though). >>>> And it's much more restritive. >>>> >>>> Experimentally I was able to determine that if we have ctx pinned >>>> above >>>> 0x10000000 (2 GB) mark, GuC Actions just fail. >>> >>> Are we certain this only applies to the kernel/golden context? No >>> other objects accessed by the GuC are affected? >>> -Chris >> >> Not sure yet. >> > >I've root caused the issue to the ring being placed in the bottom area of the GGTT >(GuC validates the ring offset as well). It looks like the allocator will place the ring >offset immediately after the ctx if the latter is placed at an offset below >0x10000000 and will instead restart from the bottom of the GGTT otherwise. > >Without Chris' patch to pin the context at the top: >CTX: 92KiB 01 01 LLC dirty (pinned x 1) (ggtt offset: 00080000, size: >00017000, type: 0) >RING:16KiB 40 40 LLC dirty (pinned x 1) (ggtt offset: 00097000, size: >00004000, type: 0) (stolen: 00002000) > >With the patch: >CTX: 92KiB 01 01 LLC dirty (pinned x 1) (ggtt offset: fede6000, size: >00017000, type: 0) >RING:16KiB 40 40 LLC dirty (pinned x 1) (ggtt offset: 00001000, size: >00004000, type: 0) (stolen: 00002000) > >Forcing the ring to be above GUC_WOPCM_TOP fixed both HuC loading and >host2guc with GuC submission for me (see diff below). Can someone verify? Works! Anusha >Daniele > >diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c >b/drivers/gpu/drm/i915/intel_ringbuffer.c >index 69ccf4f..0d944ab 100644 >--- a/drivers/gpu/drm/i915/intel_ringbuffer.c >+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c >@@ -1830,6 +1830,9 @@ int intel_ring_pin(struct intel_ring *ring) > return ret; > } > >+ if (HAS_GUC_SCHED(ring->engine->i915)) >+ flags |= PIN_OFFSET_BIAS | GUC_WOPCM_TOP; >+ > ret = i915_vma_pin(vma, 0, PAGE_SIZE, flags); > if (unlikely(ret)) > return ret; > > > >>> -- >>> Chris Wilson, Intel Open Source Technology Centre >> >_______________________________________________ >Intel-gfx mailing list >Intel-gfx@xxxxxxxxxxxxxxxxxxxxx >https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
