*/
#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"
return NULL;
}
+/*
+ * Sub buffer switch callback. Called whenever relay has to switch to a new
+ * sub buffer, relay stays on the same sub buffer if 0 is returned.
+ */
+static int subbuf_start_callback(struct rchan_buf *buf,
+ void *subbuf,
+ void *prev_subbuf,
+ size_t prev_padding)
+{
+ /* Use no-overwrite mode by default, where relay will stop accepting
+ * new data if there are no empty sub buffers left.
+ * There is no strict synchronization enforced by relay between Consumer
+ * and Producer. In overwrite mode, there is a possibility of getting
+ * inconsistent/garbled data, the producer could be writing on to the
+ * same sub buffer from which Consumer is reading. This can't be avoided
+ * unless Consumer is fast enough and can always run in tandem with
+ * Producer.
+ */
+ if (relay_buf_full(buf))
+ return 0;
+
+ 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)
+{
+ struct dentry *buf_file;
+
+ if (!parent)
+ return NULL;
+
+ /* 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 collect the logs in order without any post-processing.
+ */
+ *is_global = 1;
+
+ /* 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_log_remove_relay_file(struct intel_guc *guc)
+{
+ relay_close(guc->log.relay_chan);
+}
+
+static int guc_log_create_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;
+ }
+
+ GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
+ /* 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 unsigned int guc_get_log_buffer_size(enum guc_log_buffer_type type)
if (log_buf_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 logs\n");
+ }
}
static void guc_capture_logs_work(struct work_struct *work)
guc->log.flush_wq = NULL;
+ if (guc->log.relay_chan)
+ guc_log_remove_relay_file(guc);
+
+ guc->log.relay_chan = NULL;
+
if (guc->log.buf_addr)
i915_gem_object_unpin_map(guc->log.vma->obj);
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 setup needed to
+ * handle log buffer flush interrupts would not have been done yet,
+ * so do that now.
+ */
+ ret = guc_log_create_extras(guc);
+ if (ret)
+ goto err;
+
+ ret = guc_log_create_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 guc_policies_init(struct guc_policies *policies)
{
struct guc_policy *policy;
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)
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);
+}
projects / platform / kernel / linux-rpi.git / commitdiff