diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 45a5eb71e8e6..af13c624de9d 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -11,6 +11,7 @@ config DRM_I915 select DRM_KMS_HELPER select DRM_PANEL select DRM_MIPI_DSI + select RELAY # i915 depends on ACPI_VIDEO when ACPI is enabled # but for select to work, need to select ACPI_VIDEO's dependencies, ick select BACKLIGHT_LCD_SUPPORT if ACPI diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 99e4e044e958..af3559d34328 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1111,6 +1111,7 @@ static void i915_driver_register(struct drm_i915_private *dev_priv) /* Reveal our presence to userspace */ if (drm_dev_register(dev, 0) == 0) { i915_debugfs_register(dev_priv); + i915_guc_register(dev_priv); i915_setup_sysfs(dev_priv); } else DRM_ERROR("Failed to register driver for userspace access!\n"); @@ -1149,6 +1150,7 @@ static void i915_driver_unregister(struct drm_i915_private *dev_priv) intel_opregion_unregister(dev_priv); i915_teardown_sysfs(dev_priv); + i915_guc_unregister(dev_priv); i915_debugfs_unregister(dev_priv); drm_dev_unregister(&dev_priv->drm); diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index 1f27de2c0e1b..c1d2a9042a1c 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -23,6 +23,8 @@ */ #include #include +#include +#include #include "i915_drv.h" #include "intel_guc.h" @@ -856,13 +858,160 @@ guc_client_alloc(struct drm_i915_private *dev_priv, 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) @@ -943,6 +1092,12 @@ static void guc_read_update_log_buffer(struct intel_guc *guc) 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) @@ -967,6 +1122,11 @@ static void guc_log_cleanup(struct intel_guc *guc) 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); @@ -1057,6 +1217,36 @@ static void guc_log_create(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 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; @@ -1238,7 +1428,6 @@ 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) @@ -1312,3 +1501,23 @@ 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 fb72313c8649..e7999dd0f315 100644 --- a/drivers/gpu/drm/i915/intel_guc.h +++ b/drivers/gpu/drm/i915/intel_guc.h @@ -129,6 +129,7 @@ struct intel_guc_log { void *buf_addr; struct workqueue_struct *flush_wq; struct work_struct flush_work; + struct rchan *relay_chan; }; struct intel_guc { @@ -174,5 +175,7 @@ void i915_guc_wq_unreserve(struct drm_i915_gem_request *request); 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