@@ -23,6 +23,8 @@
*/
#include <linux/firmware.h>
#include <linux/circ_buf.h>
+#include <linux/debugfs.h>
+#include <linux/relay.h>
#include "i915_drv.h"
#include "intel_guc.h"
@@ -771,7 +773,15 @@ err:
static void* guc_get_write_buffer(struct intel_guc *guc)
{
- return NULL;
+ if (!guc->log_relay_chan)
+ return NULL;
+
+ /* Get the pointer to relay sub buffer and copy data into it ourselves.
+ * Could have used the relay_write() to indirectly copy the data, but
+ * that would have been bit convoluted, as we also need to update the
+ * first page containing state data.
+ */
+ return relay_reserve(guc->log_relay_chan, guc->log_obj->base.size);
}
static void guc_read_update_log_buffer(struct drm_device *dev)
@@ -828,6 +838,125 @@ static void guc_read_update_log_buffer(struct drm_device *dev)
}
}
+/*
+ * Sub buffer switch callback. If this callback is not implemented
+ * relay will operate in non-overwrite mode so will stop accepting
+ * new data if there are no empty sub buffers left.
+ */
+static int subbuf_start_callback(struct rchan_buf *buf,
+ void *subbuf,
+ void *prev_subbuf,
+ size_t prev_padding)
+{
+ /* Always switch to next sub buffer as we don't mind overwriting of
+ * old data/logs.
+ */
+ return 1;
+}
+
+/*
+ * file_create() callback. Creates relay file in debugfs.
+ */
+static struct dentry *create_buf_file_callback(const char *filename,
+ struct dentry *parent,
+ umode_t mode,
+ struct rchan_buf *buf,
+ int *is_global)
+{
+ /*
+ * 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.
+ */
+ struct dentry *buf_file = debugfs_create_file("guc_log", mode,
+ parent, buf, &relay_file_operations);
+
+ /* This to enable the use of a single buffer for the relay channel and
+ * correspondingly have a single file exposed to User, through which
+ * it can pull the logs in order without any post-processing.
+ */
+ *is_global = 1;
+
+ 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 void guc_create_log_relay_file(struct intel_guc *guc)
+{
+ struct drm_i915_private *dev_priv = guc_to_i915(guc);
+ struct drm_device *dev = dev_priv->dev;
+ struct dentry *log_dir;
+ struct rchan *guc_log_relay_chan;
+ size_t n_subbufs, subbuf_size;
+
+ if (guc->log_relay_chan)
+ return;
+
+ /* 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.
+ */
+ if (!dev->primary->debugfs_root) {
+ /* logging will remain off */
+ i915.guc_log_level = -1;
+ return;
+ }
+
+ /* For now create the log file in /sys/kernel/debug/dri dir. */
+ log_dir = dev->primary->debugfs_root->d_parent;
+
+ /* Keep the size of sub buffers same as shared log buffer */
+ subbuf_size = guc->log_obj->base.size;
+ /* TODO: Decide based on the User's input */
+ n_subbufs = 4;
+
+ guc_log_relay_chan = relay_open("guc_log", log_dir,
+ subbuf_size, n_subbufs, &relay_callbacks, dev);
+
+ if (!guc_log_relay_chan) {
+ DRM_ERROR("Couldn't create relay chan for guc logs\n");
+ /* keep logging off as couldn't create the relay channel in
+ * in which the logs can be stored.
+ */
+ i915.guc_log_level = -1;
+ return;
+ }
+
+ guc->log_relay_chan = guc_log_relay_chan;
+}
+
+static void guc_logging_fini(struct intel_guc *guc)
+{
+ guc_remove_log_relay_file(guc);
+}
+
+static void guc_logging_init(struct intel_guc *guc)
+{
+ guc_create_log_relay_file(guc);
+}
+
static void guc_create_log(struct intel_guc *guc)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
@@ -864,6 +993,7 @@ static void guc_create_log(struct intel_guc *guc)
offset = i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT; /* in pages */
guc->log_flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
+ guc_logging_init(guc);
}
static void init_guc_policies(struct guc_policies *policies)
@@ -1028,6 +1158,7 @@ void i915_guc_submission_fini(struct drm_device *dev)
gem_release_guc_obj(dev_priv->guc.log_obj);
guc->log_obj = NULL;
+ guc_logging_fini(guc);
if (guc->ctx_pool_obj)
ida_destroy(&guc->ctx_ids);
@@ -125,6 +125,7 @@ struct intel_guc {
struct intel_guc_fw guc_fw;
uint32_t log_flags;
struct drm_i915_gem_object *log_obj;
+ struct rchan *log_relay_chan;
/*
* work, interrupts_enabled are protected by dev_priv->irq_lock
*/