From: Akash Goel <akash.goel@xxxxxxxxx> GuC firmware log its debug messages into a Host-GuC shared memory buffer and when the buffer is half full it sends a Flush interrupt to Host. GuC firmware expects that while it is writing to 2nd half of the buffer, first half would get consumed by Host and then get a flush completed acknowledgement from Host, so that it does not end up doing any overwrite causing loss of logs. So far Flush interrupt wasn't enabled on Host side & User could capture the contents/snapshot of log buffer through 'i915_guc_log_dump' debugfs iface. But this couldn't meet couple of key requirements, especially of Validation, first is to ensure capturing of all boot time logs even with high verbosity level and second is to enable capturing of logs in a sustained manner like for the entire duration of a workload. Now Driver will enable Flush interrupt and on receving it, would copy the contents of log buffer into its local buffer. The size of local buffer would be big enough to contain multiple snapshots of the log buffer giving ample time to User to pull boot time messages. Have added a debugfs interface '/sys/kernel/debug/dri/guc_log' for User to collect the logs. Availed relay framework to implement this interface, where Driver will have to just use a relay API to store snapshots of GuC log buffer in a buffer managed by relay. The relay buffer will be operated in a mode where the old data, not yet collected by User, will be overwritten if buffer becomes full. So the behavior exhibited will be equivalent to 'dmesg -c'. Besides mmap method, through which User can directly access the relay buffer contents, relay also supports the 'poll' method. Through the 'poll' call on log file, User can come to know whenever a new snapshot of the log buffer is taken by Driver, so can run in tandem with the Driver and thus capture logs in a sustained/streaming manner, without any loss of data. v2: Rebased to the latest drm-intel-nightly. v3: Aligned with the modification of late debugfs registration, at the end of i915 Driver load. Did cleanup as per Tvrtko's review comments, added 3 new patches to optimize the log-buffer flush interrupt handling, gather and report the logging related stats. Akash Goel (8): drm/i915: New structure to contain GuC logging related fields drm/i915: Add low level set of routines for programming PM IER/IIR/IMR register set drm/i915: Add a relay backed debugfs interface for capturing GuC logs drm/i915: New module param to control the size of buffer used for storing GuC firmware logs drm/i915: Use uncached(WC) mapping for acessing the GuC log buffer drm/i915: New lock to serialize the Host2GuC actions drm/i915: Add stats for GuC log buffer flush interrupts drm/i915: Optimization to reduce the sampling time of GuC log buffer Chris Wilson (1): drm/i915: Support to create write combined type vmaps Sagar Arun Kamble (5): drm/i915: Add GuC ukernel logging related fields to fw interface file drm/i915: Support for GuC interrupts drm/i915: Handle log buffer flush interrupt event from GuC drm/i915: Forcefully flush GuC log buffer on reset drm/i915: Debugfs support for GuC logging control drivers/gpu/drm/i915/i915_debugfs.c | 60 +++- drivers/gpu/drm/i915/i915_drv.c | 15 + drivers/gpu/drm/i915/i915_drv.h | 6 +- drivers/gpu/drm/i915/i915_gem.c | 57 +++- drivers/gpu/drm/i915/i915_gem_dmabuf.c | 2 +- drivers/gpu/drm/i915/i915_guc_submission.c | 434 ++++++++++++++++++++++++++++- drivers/gpu/drm/i915/i915_irq.c | 175 ++++++++++-- drivers/gpu/drm/i915/i915_params.c | 5 + drivers/gpu/drm/i915/i915_params.h | 1 + drivers/gpu/drm/i915/i915_reg.h | 11 + drivers/gpu/drm/i915/intel_drv.h | 6 + drivers/gpu/drm/i915/intel_guc.h | 28 +- drivers/gpu/drm/i915/intel_guc_fwif.h | 64 +++++ drivers/gpu/drm/i915/intel_guc_loader.c | 6 +- drivers/gpu/drm/i915/intel_lrc.c | 8 +- drivers/gpu/drm/i915/intel_ringbuffer.c | 6 +- 16 files changed, 832 insertions(+), 52 deletions(-) -- 1.9.2 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx