Commit 882be6e0 authored by Michal Wajdeczko's avatar Michal Wajdeczko Committed by Daniel Vetter
Browse files

drm/i915/guc: Stop using fence/status from CTB descriptor 



Stop using fence/status from CTB descriptor as future GuC ABI will
no longer support replies over CTB descriptor.

Signed-off-by: default avatarMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603051630.2635-8-matthew.brost@intel.com
parent ded32d38

drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h

+2 −2
Original line number Diff line number Diff line
@@ -71,8 +71,8 @@ struct guc_ct_buffer_desc { 
	u32 head;		/* offset updated by GuC*/

	u32 tail;		/* offset updated by owner */

	u32 is_in_error;	/* error indicator */

	u32 fence;		/* fence updated by GuC */

	u32 status;		/* status updated by GuC */

	u32 reserved1;

	u32 reserved2;

	u32 owner;		/* id of the channel owner */

	u32 owner_sub_id;	/* owner-defined field for extra tracking */

	u32 reserved[5];

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c

+4 −68
Original line number Diff line number Diff line
@@ -90,13 +90,6 @@ static void guc_ct_buffer_desc_init(struct guc_ct_buffer_desc *desc, 
	desc->owner = CTB_OWNER_HOST;

}



static void guc_ct_buffer_desc_reset(struct guc_ct_buffer_desc *desc)

{

	desc->head = 0;

	desc->tail = 0;

	desc->is_in_error = 0;

}



static int guc_action_register_ct_buffer(struct intel_guc *guc,

					 u32 desc_addr,

					 u32 type)
@@ -315,8 +308,7 @@ static u32 ct_get_next_fence(struct intel_guc_ct *ct) 
static int ct_write(struct intel_guc_ct *ct,

		    const u32 *action,

		    u32 len /* in dwords */,

		    u32 fence,

		    bool want_response)

		    u32 fence)

{

	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_SEND];

	struct guc_ct_buffer_desc *desc = ctb->desc;
@@ -360,8 +352,7 @@ static int ct_write(struct intel_guc_ct *ct, 
	 * DW2+: action data

	 */

	header = (len << GUC_CT_MSG_LEN_SHIFT) |

		 (GUC_CT_MSG_WRITE_FENCE_TO_DESC) |

		 (want_response ? GUC_CT_MSG_SEND_STATUS : 0) |

		 GUC_CT_MSG_SEND_STATUS |

		 (action[0] << GUC_CT_MSG_ACTION_SHIFT);



	CT_DEBUG(ct, "writing %*ph %*ph %*ph\n",
@@ -390,56 +381,6 @@ static int ct_write(struct intel_guc_ct *ct, 
	return -EPIPE;

}



/**

 * wait_for_ctb_desc_update - Wait for the CT buffer descriptor update.

 * @desc:	buffer descriptor

 * @fence:	response fence

 * @status:	placeholder for status

 *

 * Guc will update CT buffer descriptor with new fence and status

 * after processing the command identified by the fence. Wait for

 * specified fence and then read from the descriptor status of the

 * command.

 *

 * Return:

 * *	0 response received (status is valid)

 * *	-ETIMEDOUT no response within hardcoded timeout

 * *	-EPROTO no response, CT buffer is in error

 */

static int wait_for_ctb_desc_update(struct guc_ct_buffer_desc *desc,

				    u32 fence,

				    u32 *status)

{

	int err;



	/*

	 * Fast commands should complete in less than 10us, so sample quickly

	 * up to that length of time, then switch to a slower sleep-wait loop.

	 * No GuC command should ever take longer than 10ms.

	 */

#define done (READ_ONCE(desc->fence) == fence)

	err = wait_for_us(done, 10);

	if (err)

		err = wait_for(done, 10);

#undef done



	if (unlikely(err)) {

		DRM_ERROR("CT: fence %u failed; reported fence=%u\n",

			  fence, desc->fence);



		if (WARN_ON(desc->is_in_error)) {

			/* Something went wrong with the messaging, try to reset

			 * the buffer and hope for the best

			 */

			guc_ct_buffer_desc_reset(desc);

			err = -EPROTO;

		}

	}



	*status = desc->status;

	return err;

}



/**

 * wait_for_ct_request_update - Wait for CT request state update.

 * @req:	pointer to pending request
@@ -483,8 +424,6 @@ static int ct_send(struct intel_guc_ct *ct, 
		   u32 response_buf_size,

		   u32 *status)

{

	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_SEND];

	struct guc_ct_buffer_desc *desc = ctb->desc;

	struct ct_request request;

	unsigned long flags;

	u32 fence;
@@ -505,16 +444,13 @@ static int ct_send(struct intel_guc_ct *ct, 
	list_add_tail(&request.link, &ct->requests.pending);

	spin_unlock_irqrestore(&ct->requests.lock, flags);



	err = ct_write(ct, action, len, fence, !!response_buf);

	err = ct_write(ct, action, len, fence);

	if (unlikely(err))

		goto unlink;



	intel_guc_notify(ct_to_guc(ct));



	if (response_buf)

	err = wait_for_ct_request_update(&request, status);

	else

		err = wait_for_ctb_desc_update(desc, fence, status);

	if (unlikely(err))

		goto unlink;