[RFC PATCH 13/97] drm/i915/guc: Replace CTB array with explicit members

[Matthew Brost]

On Thu, May 06, 2021 at 12:13:27PM -0700, Matthew Brost wrote:
> From: Michal Wajdeczko <michal.wajdeczko at intel.com>
> 
> Upcoming GuC firmware will always require just two CTBs and we
> also plan to configure them with different sizes, so definining
> them as array is no longer suitable.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Signed-off-by: Matthew Brost <matthew.brost at intel.com>

Reviewed-by: Matthew Brost <matthew.brost at intel.com>

> ---
>  drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 46 ++++++++++++-----------
>  drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h |  7 +++-
>  2 files changed, 30 insertions(+), 23 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 fbd6bd20f588..c54a29176862 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> @@ -168,10 +168,10 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
>  	struct intel_guc *guc = ct_to_guc(ct);
>  	struct guc_ct_buffer_desc *desc;
>  	u32 blob_size;
> +	u32 cmds_size;
>  	void *blob;
>  	u32 *cmds;
>  	int err;
> -	int i;
>  
>  	GEM_BUG_ON(ct->vma);
>  
> @@ -207,15 +207,23 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
>  
>  	CT_DEBUG(ct, "base=%#x size=%u\n", intel_guc_ggtt_offset(guc, ct->vma), blob_size);
>  
> -	/* store pointers to desc and cmds */
> -	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
> -		GEM_BUG_ON((i !=  CTB_SEND) && (i != CTB_RECV));
> +	/* store pointers to desc and cmds for send ctb */
> +	desc = blob;
> +	cmds = blob + PAGE_SIZE / 2;
> +	cmds_size = PAGE_SIZE / 4;
> +	CT_DEBUG(ct, "%s desc %#lx cmds %#lx size %u\n", "send",
> +		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
>  
> -		desc = blob + PAGE_SIZE / 4 * i;
> -		cmds = blob + PAGE_SIZE / 4 * i + PAGE_SIZE / 2;
> +	guc_ct_buffer_init(&ct->ctbs.send, desc, cmds, cmds_size);
>  
> -		guc_ct_buffer_init(&ct->ctbs[i], desc, cmds, PAGE_SIZE / 4);
> -	}
> +	/* store pointers to desc and cmds for recv ctb */
> +	desc = blob + PAGE_SIZE / 4;
> +	cmds = blob + PAGE_SIZE / 4 + PAGE_SIZE / 2;
> +	cmds_size = PAGE_SIZE / 4;
> +	CT_DEBUG(ct, "%s desc %#lx cmds %#lx size %u\n", "recv",
> +		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
> +
> +	guc_ct_buffer_init(&ct->ctbs.recv, desc, cmds, cmds_size);
>  
>  	return 0;
>  }
> @@ -246,7 +254,6 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
>  	u32 base, cmds;
>  	void *blob;
>  	int err;
> -	int i;
>  
>  	GEM_BUG_ON(ct->enabled);
>  
> @@ -257,28 +264,25 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
>  
>  	/* blob should start with send descriptor */
>  	blob = __px_vaddr(ct->vma->obj);
> -	GEM_BUG_ON(blob != ct->ctbs[CTB_SEND].desc);
> +	GEM_BUG_ON(blob != ct->ctbs.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 + ptrdiff(ct->ctbs.send.cmds, blob);
> +	guc_ct_buffer_reset(&ct->ctbs.send, cmds);
>  
> -		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);
> -	}
> +	cmds = base + ptrdiff(ct->ctbs.recv.cmds, blob);
> +	guc_ct_buffer_reset(&ct->ctbs.recv, cmds);
>  
>  	/*
>  	 * Register both CT buffers starting with RECV buffer.
>  	 * Descriptors are in first half of the blob.
>  	 */
> -	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_RECV].desc, blob),
> +	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.recv.desc, blob),
>  				 INTEL_GUC_CT_BUFFER_TYPE_RECV);
>  	if (unlikely(err))
>  		goto err_out;
>  
> -	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_SEND].desc, blob),
> +	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.send.desc, blob),
>  				 INTEL_GUC_CT_BUFFER_TYPE_SEND);
>  	if (unlikely(err))
>  		goto err_deregister;
> @@ -341,7 +345,7 @@ static int ct_write(struct intel_guc_ct *ct,
>  		    u32 len /* in dwords */,
>  		    u32 fence)
>  {
> -	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_SEND];
> +	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
>  	struct guc_ct_buffer_desc *desc = ctb->desc;
>  	u32 head = desc->head;
>  	u32 tail = desc->tail;
> @@ -557,7 +561,7 @@ static inline bool ct_header_is_response(u32 header)
>  
>  static int ct_read(struct intel_guc_ct *ct, u32 *data)
>  {
> -	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_RECV];
> +	struct intel_guc_ct_buffer *ctb = &ct->ctbs.recv;
>  	struct guc_ct_buffer_desc *desc = ctb->desc;
>  	u32 head = desc->head;
>  	u32 tail = desc->tail;
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
> index 4009e2dd0de4..fc9486779e87 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
> @@ -47,8 +47,11 @@ struct intel_guc_ct {
>  	struct i915_vma *vma;
>  	bool enabled;
>  
> -	/* buffers for sending(0) and receiving(1) commands */
> -	struct intel_guc_ct_buffer ctbs[2];
> +	/* buffers for sending and receiving commands */
> +	struct {
> +		struct intel_guc_ct_buffer send;
> +		struct intel_guc_ct_buffer recv;
> +	} ctbs;
>  
>  	struct {
>  		u32 last_fence; /* last fence used to send request */
> -- 
> 2.28.0
>