+
+ /* Not using the channel filename passed as an argument, since
for each
+ * channel relay appends the corresponding CPU number to the
filename
+ * passed in relay_open(). This should be fine as relay just needs a
+ * dentry of the file associated with the channel buffer and that
file's
+ * name need not be same as the filename passed as an argument.
+ */
+ buf_file = debugfs_create_file("guc_log", mode,
+ parent, buf, &relay_file_operations);
+ return buf_file;
+}
+
+/*
+ * file_remove() default callback. Removes relay file in debugfs.
+ */
+static int remove_buf_file_callback(struct dentry *dentry)
+{
+ debugfs_remove(dentry);
+ return 0;
+}
+
+/* relay channel callbacks */
+static struct rchan_callbacks relay_callbacks = {
+ .subbuf_start = subbuf_start_callback,
+ .create_buf_file = create_buf_file_callback,
+ .remove_buf_file = remove_buf_file_callback,
+};
+
+static void guc_remove_log_relay_file(struct intel_guc *guc)
+{
+ relay_close(guc->log.relay_chan);
+}
+
+static int guc_create_log_relay_file(struct intel_guc *guc)
+{
+ struct drm_i915_private *dev_priv = guc_to_i915(guc);
+ struct rchan *guc_log_relay_chan;
+ struct dentry *log_dir;
+ size_t n_subbufs, subbuf_size;
+
+ /* For now create the log file in /sys/kernel/debug/dri/0 dir */
+ log_dir = dev_priv->drm.primary->debugfs_root;
+
+ /* If /sys/kernel/debug/dri/0 location do not exist, then debugfs is
+ * not mounted and so can't create the relay file.
+ * The relay API seems to fit well with debugfs only, for
availing relay
+ * there are 3 requirements which can be met for debugfs file
only in a
+ * straightforward/clean manner :-
+ * i) Need the associated dentry pointer of the file, while
opening the
+ * relay channel.
+ * ii) Should be able to use 'relay_file_operations' fops for
the file.
+ * iii) Set the 'i_private' field of file's inode to the pointer of
+ * relay channel buffer.
+ */
+ if (!log_dir) {
+ DRM_ERROR("Debugfs dir not available yet for GuC log file\n");
+ return -ENODEV;
+ }
+
+ /* Keep the size of sub buffers same as shared log buffer */
+ subbuf_size = guc->log.vma->obj->base.size;
+
+ /* Store up to 8 snapshots, which is large enough to buffer
sufficient
+ * boot time logs and provides enough leeway to User, in terms of
+ * latency, for consuming the logs from relay. Also doesn't take
+ * up too much memory.
+ */
+ n_subbufs = 8;
+
+ guc_log_relay_chan = relay_open("guc_log", log_dir, subbuf_size,
+ n_subbufs, &relay_callbacks, dev_priv);
+ if (!guc_log_relay_chan) {
+ DRM_ERROR("Couldn't create relay chan for GuC logging\n");
+ return -ENOMEM;
+ }
+
+ /* FIXME: Cover the update under a lock ? */
+ guc->log.relay_chan = guc_log_relay_chan;
+ return 0;
+}
+
static void guc_move_to_next_buf(struct intel_guc *guc)
{
+ /* Make sure the updates made in the sub buffer are visible when
+ * Consumer sees the following update to offset inside the sub
buffer.
+ */
+ smp_wmb();
+
+ /* All data has been written, so now move the offset of sub
buffer. */
+ relay_reserve(guc->log.relay_chan, guc->log.vma->obj->base.size);
+
+ /* Switch to the next sub buffer */
+ relay_flush(guc->log.relay_chan);
}
static void *guc_get_write_buffer(struct intel_guc *guc)
{
- return NULL;
+ /* FIXME: Cover the check under a lock ? */
+ if (!guc->log.relay_chan)
+ return NULL;
+
+ /* Just get the base address of a new sub buffer and copy data
into it
+ * ourselves. NULL will be returned in no-overwrite mode, if all sub
+ * buffers are full. Could have used the relay_write() to indirectly
+ * copy the data, but that would have been bit convoluted, as we
need to
+ * write to only certain locations inside a sub buffer which
cannot be
+ * done without using relay_reserve() along with relay_write().
So its
+ * better to use relay_reserve() alone.
+ */
+ return relay_reserve(guc->log.relay_chan, 0);
}
static void guc_read_update_log_buffer(struct intel_guc *guc)
@@ -929,6 +1077,12 @@ static void guc_read_update_log_buffer(struct
intel_guc *guc)
if (log_buffer_snapshot_state)
guc_move_to_next_buf(guc);
+ else {
+ /* Used rate limited to avoid deluge of messages, logs might be
+ * getting consumed by User at a slow rate.
+ */
+ DRM_ERROR_RATELIMITED("no sub-buffer to capture log buffer\n");
+ }
}
static void guc_capture_logs_work(struct work_struct *work)
@@ -964,6 +1118,11 @@ static void guc_log_cleanup(struct intel_guc *guc)
guc->log.flush_wq = NULL;
+ if (guc->log.relay_chan)
+ guc_remove_log_relay_file(guc);
+
+ guc->log.relay_chan = NULL;
+
if (guc->log.buf_addr)
i915_gem_object_unpin_map(guc->log.vma->obj);
@@ -1054,6 +1213,35 @@ static void guc_create_log(struct intel_guc *guc)
guc->log.flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
}
+static int guc_log_late_setup(struct intel_guc *guc)
+{
+ struct drm_i915_private *dev_priv = guc_to_i915(guc);
+ int ret;
+
+ lockdep_assert_held(&dev_priv->drm.struct_mutex);
+
+ if (i915.guc_log_level < 0)
+ return -EINVAL;
+
+ /* If log_level was set as -1 at boot time, then vmalloc mapping
would
+ * not have been created for the log buffer, so create one now.
+ */
+ ret = guc_create_log_extras(guc);
+ if (ret)
+ goto err;
+
+ ret = guc_create_log_relay_file(guc);
+ if (ret)
+ goto err;
+
+ return 0;
+err:
+ guc_log_cleanup(guc);
+ /* logging will remain off */
+ i915.guc_log_level = -1;
+ return ret;
+}
+
static void init_guc_policies(struct guc_policies *policies)
{
struct guc_policy *policy;
@@ -1223,7 +1411,6 @@ void i915_guc_submission_fini(struct
drm_i915_private *dev_priv)
struct intel_guc *guc = &dev_priv->guc;
i915_vma_unpin_and_release(&guc->ads_vma);
- guc_log_cleanup(guc);
i915_vma_unpin_and_release(&guc->log.vma);
if (guc->ctx_pool_vma)
@@ -1297,3 +1484,23 @@ void i915_guc_capture_logs(struct
drm_i915_private *dev_priv)
host2guc_logbuffer_flush_complete(&dev_priv->guc);
intel_runtime_pm_put(dev_priv);
}
+
+void i915_guc_unregister(struct drm_i915_private *dev_priv)
+{
+ if (!i915.enable_guc_submission)
+ return;
+
+ mutex_lock(&dev_priv->drm.struct_mutex);
+ guc_log_cleanup(&dev_priv->guc);
+ mutex_unlock(&dev_priv->drm.struct_mutex);
+}
+
+void i915_guc_register(struct drm_i915_private *dev_priv)
+{
+ if (!i915.enable_guc_submission)
+ return;
+
+ mutex_lock(&dev_priv->drm.struct_mutex);
+ guc_log_late_setup(&dev_priv->guc);
+ mutex_unlock(&dev_priv->drm.struct_mutex);
+}
diff --git a/drivers/gpu/drm/i915/intel_guc.h
b/drivers/gpu/drm/i915/intel_guc.h
index d053a18..3299cce 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -127,6 +127,7 @@ struct intel_guc_log {
void *buf_addr;
struct workqueue_struct *flush_wq;
struct work_struct flush_work;
+ struct rchan *relay_chan;
};
struct intel_guc {
@@ -171,5 +172,7 @@ int i915_guc_wq_check_space(struct
drm_i915_gem_request *rq);
void i915_guc_submission_disable(struct drm_i915_private *dev_priv);
void i915_guc_submission_fini(struct drm_i915_private *dev_priv);
void i915_guc_capture_logs(struct drm_i915_private *dev_priv);
+void i915_guc_register(struct drm_i915_private *dev_priv);
+void i915_guc_unregister(struct drm_i915_private *dev_priv);
#endif
