1 files changed, 289 insertions, 0 deletions
diff --git a/drivers/gpu/drm/imagination/pvr_sync.c b/drivers/gpu/drm/imagination/pvr_sync.c
new file mode 100644
index 000000000000..129f646d14ba
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_sync.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#include <uapi/drm/pvr_drm.h>
+
+#include <drm/drm_syncobj.h>
+#include <drm/gpu_scheduler.h>
+#include <linux/xarray.h>
+#include <linux/dma-fence-unwrap.h>
+
+#include "pvr_device.h"
+#include "pvr_queue.h"
+#include "pvr_sync.h"
+
+static int
+pvr_check_sync_op(const struct drm_pvr_sync_op *sync_op)
+{
+	u8 handle_type;
+
+	if (sync_op->flags & ~DRM_PVR_SYNC_OP_FLAGS_MASK)
+		return -EINVAL;
+
+	handle_type = sync_op->flags & DRM_PVR_SYNC_OP_FLAG_HANDLE_TYPE_MASK;
+	if (handle_type != DRM_PVR_SYNC_OP_FLAG_HANDLE_TYPE_SYNCOBJ &&
+	    handle_type != DRM_PVR_SYNC_OP_FLAG_HANDLE_TYPE_TIMELINE_SYNCOBJ)
+		return -EINVAL;
+
+	if (handle_type == DRM_PVR_SYNC_OP_FLAG_HANDLE_TYPE_SYNCOBJ &&
+	    sync_op->value != 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void
+pvr_sync_signal_free(struct pvr_sync_signal *sig_sync)
+{
+	if (!sig_sync)
+		return;
+
+	drm_syncobj_put(sig_sync->syncobj);
+	dma_fence_chain_free(sig_sync->chain);
+	dma_fence_put(sig_sync->fence);
+	kfree(sig_sync);
+}
+
+void
+pvr_sync_signal_array_cleanup(struct xarray *array)
+{
+	struct pvr_sync_signal *sig_sync;
+	unsigned long i;
+
+	xa_for_each(array, i, sig_sync)
+		pvr_sync_signal_free(sig_sync);
+
+	xa_destroy(array);
+}
+
+static struct pvr_sync_signal *
+pvr_sync_signal_array_add(struct xarray *array, struct drm_file *file, u32 handle, u64 point)
+{
+	struct pvr_sync_signal *sig_sync;
+	struct dma_fence *cur_fence;
+	int err;
+	u32 id;
+
+	sig_sync = kzalloc(sizeof(*sig_sync), GFP_KERNEL);
+	if (!sig_sync)
+		return ERR_PTR(-ENOMEM);
+
+	sig_sync->handle = handle;
+	sig_sync->point = point;
+
+	if (point > 0) {
+		sig_sync->chain = dma_fence_chain_alloc();
+		if (!sig_sync->chain) {
+			err = -ENOMEM;
+			goto err_free_sig_sync;
+		}
+	}
+
+	sig_sync->syncobj = drm_syncobj_find(file, handle);
+	if (!sig_sync->syncobj) {
+		err = -EINVAL;
+		goto err_free_sig_sync;
+	}
+
+	/* Retrieve the current fence attached to that point. It's
+	 * perfectly fine to get a NULL fence here, it just means there's
+	 * no fence attached to that point yet.
+	 */
+	if (!drm_syncobj_find_fence(file, handle, point, 0, &cur_fence))
+		sig_sync->fence = cur_fence;
+
+	err = xa_alloc(array, &id, sig_sync, xa_limit_32b, GFP_KERNEL);
+	if (err)
+		goto err_free_sig_sync;
+
+	return sig_sync;
+
+err_free_sig_sync:
+	pvr_sync_signal_free(sig_sync);
+	return ERR_PTR(err);
+}
+
+static struct pvr_sync_signal *
+pvr_sync_signal_array_search(struct xarray *array, u32 handle, u64 point)
+{
+	struct pvr_sync_signal *sig_sync;
+	unsigned long i;
+
+	xa_for_each(array, i, sig_sync) {
+		if (handle == sig_sync->handle && point == sig_sync->point)
+			return sig_sync;
+	}
+
+	return NULL;
+}
+
+static struct pvr_sync_signal *
+pvr_sync_signal_array_get(struct xarray *array, struct drm_file *file, u32 handle, u64 point)
+{
+	struct pvr_sync_signal *sig_sync;
+
+	sig_sync = pvr_sync_signal_array_search(array, handle, point);
+	if (sig_sync)
+		return sig_sync;
+
+	return pvr_sync_signal_array_add(array, file, handle, point);
+}
+
+int
+pvr_sync_signal_array_collect_ops(struct xarray *array,
+				  struct drm_file *file,
+				  u32 sync_op_count,
+				  const struct drm_pvr_sync_op *sync_ops)
+{
+	for (u32 i = 0; i < sync_op_count; i++) {
+		struct pvr_sync_signal *sig_sync;
+		int ret;
+
+		if (!(sync_ops[i].flags & DRM_PVR_SYNC_OP_FLAG_SIGNAL))
+			continue;
+
+		ret = pvr_check_sync_op(&sync_ops[i]);
+		if (ret)
+			return ret;
+
+		sig_sync = pvr_sync_signal_array_get(array, file,
+						     sync_ops[i].handle,
+						     sync_ops[i].value);
+		if (IS_ERR(sig_sync))
+			return PTR_ERR(sig_sync);
+	}
+
+	return 0;
+}
+
+int
+pvr_sync_signal_array_update_fences(struct xarray *array,
+				    u32 sync_op_count,
+				    const struct drm_pvr_sync_op *sync_ops,
+				    struct dma_fence *done_fence)
+{
+	for (u32 i = 0; i < sync_op_count; i++) {
+		struct dma_fence *old_fence;
+		struct pvr_sync_signal *sig_sync;
+
+		if (!(sync_ops[i].flags & DRM_PVR_SYNC_OP_FLAG_SIGNAL))
+			continue;
+
+		sig_sync = pvr_sync_signal_array_search(array, sync_ops[i].handle,
+							sync_ops[i].value);
+		if (WARN_ON(!sig_sync))
+			return -EINVAL;
+
+		old_fence = sig_sync->fence;
+		sig_sync->fence = dma_fence_get(done_fence);
+		dma_fence_put(old_fence);
+
+		if (WARN_ON(!sig_sync->fence))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+void
+pvr_sync_signal_array_push_fences(struct xarray *array)
+{
+	struct pvr_sync_signal *sig_sync;
+	unsigned long i;
+
+	xa_for_each(array, i, sig_sync) {
+		if (sig_sync->chain) {
+			drm_syncobj_add_point(sig_sync->syncobj, sig_sync->chain,
+					      sig_sync->fence, sig_sync->point);
+			sig_sync->chain = NULL;
+		} else {
+			drm_syncobj_replace_fence(sig_sync->syncobj, sig_sync->fence);
+		}
+	}
+}
+
+static int
+pvr_sync_add_dep_to_job(struct drm_sched_job *job, struct dma_fence *f)
+{
+	struct dma_fence_unwrap iter;
+	u32 native_fence_count = 0;
+	struct dma_fence *uf;
+	int err = 0;
+
+	dma_fence_unwrap_for_each(uf, &iter, f) {
+		if (pvr_queue_fence_is_ufo_backed(uf))
+			native_fence_count++;
+	}
+
+	/* No need to unwrap the fence if it's fully non-native. */
+	if (!native_fence_count)
+		return drm_sched_job_add_dependency(job, f);
+
+	dma_fence_unwrap_for_each(uf, &iter, f) {
+		/* There's no dma_fence_unwrap_stop() helper cleaning up the refs
+		 * owned by dma_fence_unwrap(), so let's just iterate over all
+		 * entries without doing anything when something failed.
+		 */
+		if (err)
+			continue;
+
+		if (pvr_queue_fence_is_ufo_backed(uf)) {
+			struct drm_sched_fence *s_fence = to_drm_sched_fence(uf);
+
+			/* If this is a native dependency, we wait for the scheduled fence,
+			 * and we will let pvr_queue_run_job() issue FW waits.
+			 */
+			err = drm_sched_job_add_dependency(job,
+							   dma_fence_get(&s_fence->scheduled));
+		} else {
+			err = drm_sched_job_add_dependency(job, dma_fence_get(uf));
+		}
+	}
+
+	dma_fence_put(f);
+	return err;
+}
+
+int
+pvr_sync_add_deps_to_job(struct pvr_file *pvr_file, struct drm_sched_job *job,
+			 u32 sync_op_count,
+			 const struct drm_pvr_sync_op *sync_ops,
+			 struct xarray *signal_array)
+{
+	int err = 0;
+
+	if (!sync_op_count)
+		return 0;
+
+	for (u32 i = 0; i < sync_op_count; i++) {
+		struct pvr_sync_signal *sig_sync;
+		struct dma_fence *fence;
+
+		if (sync_ops[i].flags & DRM_PVR_SYNC_OP_FLAG_SIGNAL)
+			continue;
+
+		err = pvr_check_sync_op(&sync_ops[i]);
+		if (err)
+			return err;
+
+		sig_sync = pvr_sync_signal_array_search(signal_array, sync_ops[i].handle,
+							sync_ops[i].value);
+		if (sig_sync) {
+			if (WARN_ON(!sig_sync->fence))
+				return -EINVAL;
+
+			fence = dma_fence_get(sig_sync->fence);
+		} else {
+			err = drm_syncobj_find_fence(from_pvr_file(pvr_file), sync_ops[i].handle,
+						     sync_ops[i].value, 0, &fence);
+			if (err)
+				return err;
+		}
+
+		err = pvr_sync_add_dep_to_job(job, fence);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}