[Intel-gfx] [PATCH v7 08/11] drm/i915: Make addressing mode bits in context descriptor configurable

[Wang, Zhi A]

Good idea. :)

> -----Original Message-----
> From: Chris Wilson [mailto:chris at chris-wilson.co.uk]
> Sent: Wednesday, June 08, 2016 10:13 AM
> To: Wang, Zhi A <zhi.a.wang at intel.com>
> Cc: Lv, Zhiyuan <zhiyuan.lv at intel.com>; Tian, Kevin <kevin.tian at intel.com>;
> tvrtko.ursulin at linux.intel.com; intel-gfx at lists.freedesktop.org
> Subject: Re: [PATCH v7 08/11] drm/i915: Make addressing mode bits in context
> descriptor configurable
> 
> On Tue, Jun 07, 2016 at 11:18:44AM -0400, Zhi Wang wrote:
> > Currently the addressing mode bit in context descriptor is statically
> > generated from the configuration of system-wide PPGTT usage model.
> >
> > GVT-g will load the PPGTT shadow page table by itself and probably one
> > guest is using a different addressing mode with i915 host. The
> > addressing mode bits of a LRC context should be configurable under this case.
> >
> > v7
> >
> > - Move context addressing mode bit into i915_reg.h. (Joonas/Chris)
> > - Add prefix "INTEL_" for related definitions. (Joonas)
> >
> > v6:
> >
> > - Directly save the addressing mode bits inside i915_gem_context.
> > (Chris)
> > - Move the LRC context addressing mode bits into intel_lrc.h. (Chris)
> >
> > v5:
> >
> > - Change USES_FULL_48BIT(dev) to USES_FULL_48BIT(dev_priv) (Tvrtko)
> >
> > Signed-off-by: Zhi Wang <zhi.a.wang at intel.com>
> > ---
> >  drivers/gpu/drm/i915/i915_drv.h         |  1 +
> >  drivers/gpu/drm/i915/i915_gem_context.c |  2 ++
> >  drivers/gpu/drm/i915/i915_reg.h         | 12 ++++++++++++
> >  drivers/gpu/drm/i915/intel_lrc.c        | 13 +------------
> >  4 files changed, 16 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h
> > b/drivers/gpu/drm/i915/i915_drv.h index 50b3ea7..a3ef3eb 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -879,6 +879,7 @@ struct i915_gem_context {
> >  		bool initialised;
> >  	} engine[I915_NUM_ENGINES];
> >  	u32 lrc_ring_buffer_size;
> > +	u32 lrc_addressing_mode_bits;
> 
> u32 addressing_mode.
> 
> Though this is better as ctx->desc_template; -Chris
> 
> --
> Chris Wilson, Intel Open Source Technology Centre