drm/v3d: Create a CPU job extension for the timestamp query job

A CPU job is a type of job that performs operations that requires CPU
intervention. A timestamp query job is a job that calculates the
query timestamp and updates the query availability by signaling a
syncobj. As V3D doesn't provide any mechanism to obtain a timestamp
from the GPU, it is a job that needs CPU intervention.

So, create a user extension for the CPU job that enables the creation
of a timestamp query job. This user extension will allow the creation of
a CPU job that performs the timestamp query calculation and updates the
timestamp BO with the proper value.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231130164420.932823-15-mcanal@igalia.com

1 files changed, 63 insertions, 0 deletions

diff --git a/drivers/gpu/drm/v3d/v3d_submit.c b/drivers/gpu/drm/v3d/v3d_submit.c
index 0320695b941b..83e029e786ea 100644
--- a/drivers/gpu/drm/v3d/v3d_submit.c
+++ b/drivers/gpu/drm/v3d/v3d_submit.c
@@ -433,6 +433,64 @@ v3d_get_cpu_indirect_csd_params(struct drm_file *file_priv,
 					  NULL, &info->acquire_ctx);
 }
 
+/* Get data for the query timestamp job submission. */
+static int
+v3d_get_cpu_timestamp_query_params(struct drm_file *file_priv,
+				   struct drm_v3d_extension __user *ext,
+				   struct v3d_cpu_job *job)
+{
+	u32 __user *offsets, *syncs;
+	struct drm_v3d_timestamp_query timestamp;
+
+	if (!job) {
+		DRM_DEBUG("CPU job extension was attached to a GPU job.\n");
+		return -EINVAL;
+	}
+
+	if (job->job_type) {
+		DRM_DEBUG("Two CPU job extensions were added to the same CPU job.\n");
+		return -EINVAL;
+	}
+
+	if (copy_from_user(&timestamp, ext, sizeof(timestamp)))
+		return -EFAULT;
+
+	if (timestamp.pad)
+		return -EINVAL;
+
+	job->job_type = V3D_CPU_JOB_TYPE_TIMESTAMP_QUERY;
+
+	job->timestamp_query.queries = kvmalloc_array(timestamp.count,
+						      sizeof(struct v3d_timestamp_query),
+						      GFP_KERNEL);
+	if (!job->timestamp_query.queries)
+		return -ENOMEM;
+
+	offsets = u64_to_user_ptr(timestamp.offsets);
+	syncs = u64_to_user_ptr(timestamp.syncs);
+
+	for (int i = 0; i < timestamp.count; i++) {
+		u32 offset, sync;
+
+		if (copy_from_user(&offset, offsets++, sizeof(offset))) {
+			kvfree(job->timestamp_query.queries);
+			return -EFAULT;
+		}
+
+		job->timestamp_query.queries[i].offset = offset;
+
+		if (copy_from_user(&sync, syncs++, sizeof(sync))) {
+			kvfree(job->timestamp_query.queries);
+			return -EFAULT;
+		}
+
+		job->timestamp_query.queries[i].syncobj = drm_syncobj_find(file_priv, sync);
+	}
+	job->timestamp_query.count = timestamp.count;
+
+	return 0;
+}
+
 /* Whenever userspace sets ioctl extensions, v3d_get_extensions parses data
  * according to the extension id (name).
  */
@@ -461,6 +519,9 @@ v3d_get_extensions(struct drm_file *file_priv,
 		case DRM_V3D_EXT_ID_CPU_INDIRECT_CSD:
 			ret = v3d_get_cpu_indirect_csd_params(file_priv, user_ext, job);
 			break;
+		case DRM_V3D_EXT_ID_CPU_TIMESTAMP_QUERY:
+			ret = v3d_get_cpu_timestamp_query_params(file_priv, user_ext, job);
+			break;
 		default:
 			DRM_DEBUG_DRIVER("Unknown extension id: %d\n", ext.id);
 			return -EINVAL;
@@ -837,6 +898,7 @@ fail:
 
 static const unsigned int cpu_job_bo_handle_count[] = {
 	[V3D_CPU_JOB_TYPE_INDIRECT_CSD] = 1,
+	[V3D_CPU_JOB_TYPE_TIMESTAMP_QUERY] = 1,
 };
 
 /**
@@ -974,6 +1036,7 @@ fail:
 	v3d_job_cleanup((void *)csd_job);
 	v3d_job_cleanup(clean_job);
 	v3d_put_multisync_post_deps(&se);
+	kvfree(cpu_job->timestamp_query.queries);
 
 	return ret;
 }