[RFC PATCH 12/97] drm/i915/guc: Don't repeat CTB layout calculations

[Matthew Brost]

On Tue, May 25, 2021 at 03:07:06PM +0200, Michal Wajdeczko wrote:
> 
> 
> On 25.05.2021 04:53, Matthew Brost wrote:
> > On Thu, May 06, 2021 at 12:13:26PM -0700, Matthew Brost wrote:
> >> From: Michal Wajdeczko <michal.wajdeczko at intel.com>
> >>
> >> We can retrieve offsets to cmds buffers and descriptor from
> >> actual pointers that we already keep locally.
> >>
> >> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> >> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 16 ++++++++++------
> >>  1 file changed, 10 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> index dbece569fbe4..fbd6bd20f588 100644
> >> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> @@ -244,6 +244,7 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
> >>  {
> >>  	struct intel_guc *guc = ct_to_guc(ct);
> >>  	u32 base, cmds;
> >> +	void *blob;
> >>  	int err;
> >>  	int i;
> >>  
> >> @@ -251,15 +252,18 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
> >>  
> >>  	/* vma should be already allocated and map'ed */
> >>  	GEM_BUG_ON(!ct->vma);
> >> +	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(ct->vma->obj));
> > 
> > This doesn't really have anything to do with this patch, but again this
> > patch will be squashed into a large patch updating the GuC firmware, so
> > I think this is fine.
> 
> again, no need to squash GuC patches up to 20/97
> 

Got it. As discussed I will post patches 4-20 after I done reviewing all
of them.

Matt 

> > 
> > With that:
> > Reviewed-by: Matthew Brost <matthew.brost at intel.com>
> > 
> >>  	base = intel_guc_ggtt_offset(guc, ct->vma);
> >>  
> >> -	/* (re)initialize descriptors
> >> -	 * cmds buffers are in the second half of the blob page
> >> -	 */
> >> +	/* blob should start with send descriptor */
> >> +	blob = __px_vaddr(ct->vma->obj);
> >> +	GEM_BUG_ON(blob != ct->ctbs[CTB_SEND].desc);
> >> +
> >> +	/* (re)initialize descriptors */
> >>  	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
> >>  		GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV));
> >>  
> >> -		cmds = base + PAGE_SIZE / 4 * i + PAGE_SIZE / 2;
> >> +		cmds = base + ptrdiff(ct->ctbs[i].cmds, blob);
> >>  		CT_DEBUG(ct, "%d: cmds addr=%#x\n", i, cmds);
> >>  
> >>  		guc_ct_buffer_reset(&ct->ctbs[i], cmds);
> >> @@ -269,12 +273,12 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
> >>  	 * Register both CT buffers starting with RECV buffer.
> >>  	 * Descriptors are in first half of the blob.
> >>  	 */
> >> -	err = ct_register_buffer(ct, base + PAGE_SIZE / 4 * CTB_RECV,
> >> +	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_RECV].desc, blob),
> >>  				 INTEL_GUC_CT_BUFFER_TYPE_RECV);
> >>  	if (unlikely(err))
> >>  		goto err_out;
> >>  
> >> -	err = ct_register_buffer(ct, base + PAGE_SIZE / 4 * CTB_SEND,
> >> +	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_SEND].desc, blob),
> >>  				 INTEL_GUC_CT_BUFFER_TYPE_SEND);
> >>  	if (unlikely(err))
> >>  		goto err_deregister;
> >> -- 
> >> 2.28.0
> >>