| Message ID | 20231110171811.11656-1-hamza.mahfooz@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amd/display: add a debugfs interface for the DMUB trace mask | expand |
On 2023-11-10 12:18, Hamza Mahfooz wrote: > For features that are implemented primarily in DMUB (e.g. PSR), it is > useful to be able to trace them at a DMUB level from the kernel, > especially when debugging issues. So, introduce a debugfs interface that > is able to read and set the DMUB trace mask dynamically at runtime and > document how to use it. > > Cc: Alex Deucher <alexander.deucher@amd.com> > Cc: Mario Limonciello <mario.limonciello@amd.com> > Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com> > --- > Documentation/gpu/amdgpu/display/dc-debug.rst | 41 +++++++++ > .../gpu/amdgpu/display/trace-groups-table.csv | 29 ++++++ > .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 91 +++++++++++++++++++ > .../gpu/drm/amd/display/dmub/inc/dmub_cmd.h | 40 +++++++- > 4 files changed, 199 insertions(+), 2 deletions(-) > create mode 100644 Documentation/gpu/amdgpu/display/trace-groups-table.csv > > diff --git a/Documentation/gpu/amdgpu/display/dc-debug.rst b/Documentation/gpu/amdgpu/display/dc-debug.rst > index 40c55a618918..817631b1dbf3 100644 > --- a/Documentation/gpu/amdgpu/display/dc-debug.rst > +++ b/Documentation/gpu/amdgpu/display/dc-debug.rst > @@ -75,3 +75,44 @@ change in real-time by using something like:: > > When reporting a bug related to DC, consider attaching this log before and > after you reproduce the bug. > + > +DMUB Firmware Debug > +=================== > + > +Sometimes, dmesg logs aren't enough. This is especially true if a feature is > +implemented primarily in DMUB firmware. In such cases, all we see in dmesg when > +an issue arises is some generic timeout error. So, to get more relevant > +information, we can trace DMUB commands by enabling the relevant bits in > +`amdgpu_dm_dmub_trace_mask`. > + > +Currently, we support the tracing of the following groups: > + > +Trace Groups > +------------ > + > +.. csv-table:: > + :header-rows: 1 > + :widths: 1, 1 > + :file: ./trace-groups-table.csv > + > +**Note: Not all ASICs support all of the listed trace groups** > + > +So, to enable just PSR tracing you can use the following command:: > + > + # echo 0x8020 > /sys/kernel/debug/dri/0/amdgpu_dm_dmub_trace_mask > + > +Then, you need to enable logging trace events to the buffer, which you can do > +using the following:: > + > + # echo 1 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en > + > +Lastly, after you are able to reproduce the issue you are trying to debug, > +you can disable tracing and read the trace log by using the following:: > + > + # echo 0 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en > + # cat /sys/kernel/debug/dri/0/amdgpu_dm_dmub_tracebuffer > + > +So, when reporting bugs related to features such as PSR and ABM, consider > +enabling the relevant bits in the mask before reproducing the issue and > +attach the log that you obtain from the trace buffer in any bug reports that you > +create. > diff --git a/Documentation/gpu/amdgpu/display/trace-groups-table.csv b/Documentation/gpu/amdgpu/display/trace-groups-table.csv > new file mode 100644 > index 000000000000..3f6a50d1d883 > --- /dev/null > +++ b/Documentation/gpu/amdgpu/display/trace-groups-table.csv > @@ -0,0 +1,29 @@ > +Name, Mask Value > +INFO, 0x1 > +IRQ SVC, 0x2 > +VBIOS, 0x4 > +REGISTER, 0x8 > +PHY DBG, 0x10 > +PSR, 0x20 > +AUX, 0x40 > +SMU, 0x80 > +MALL, 0x100 > +ABM, 0x200 > +ALPM, 0x400 > +TIMER, 0x800 > +HW LOCK MGR, 0x1000 > +INBOX1, 0x2000 > +PHY SEQ, 0x4000 > +PSR STATE, 0x8000 > +ZSTATE, 0x10000 > +TRANSMITTER CTL, 0x20000 > +PANEL CNTL, 0x40000 > +FAMS, 0x80000 > +DPIA, 0x100000 > +SUBVP, 0x200000 > +INBOX0, 0x400000 > +SDP, 0x4000000 > +REPLAY, 0x8000000 > +REPLAY RESIDENCY, 0x20000000 > +CURSOR INFO, 0x80000000 > +IPS, 0x100000000 > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c > index 13a177d34376..06a73f283e9d 100644 > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c > @@ -2971,6 +2971,94 @@ static int allow_edp_hotplug_detection_set(void *data, u64 val) > return 0; > } > > +static int dmub_trace_mask_set(void *data, u64 val) > +{ > + struct amdgpu_device *adev = data; > + struct dmub_srv *srv = adev->dm.dc->ctx->dmub_srv->dmub; > + enum dmub_gpint_command cmd; > + enum dmub_status status; > + u64 mask = 0xffff; > + u8 shift = 0; > + u32 res; > + int i; > + > + if (!srv->fw_version) > + return -EINVAL; > + > + for (i = 0; i < 4; i++) { > + res = (val & mask) >> shift; > + > + switch (i) { > + case 0: > + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD0; > + break; > + case 1: > + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD1; > + break; > + case 2: > + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD2; > + break; > + case 3: > + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD3; > + break; > + } > + > + status = dmub_srv_send_gpint_command(srv, cmd, res, 30); > + > + if (status != DMUB_STATUS_OK) > + return -ETIMEDOUT; dmub_srv_send_gpint_command() explicitly sends out DMUB_STATUS_TIMEOUT, so it would nice to check that instead of sending out timeout error unconditionally. if (status == DMUB_STATUS_TIMEOUT) return -ETIMEDOUT else if (status != DMUB_STATUS_OK) return -EIO; // or something else more suited > + > + usleep_range(100, 1000); > + > + mask <<= 16; > + shift += 16; > + } > + > + return 0; > +} > + > +static int dmub_trace_mask_show(void *data, u64 *val) > +{ > + enum dmub_gpint_command cmd = DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD0; > + struct amdgpu_device *adev = data; > + struct dmub_srv *srv = adev->dm.dc->ctx->dmub_srv->dmub; > + enum dmub_status status; > + u8 shift = 0; > + u64 raw = 0; > + u64 res = 0; > + int i = 0; > + > + if (!srv->fw_version) > + return -EINVAL; > + > + while (i < 4) { > + status = dmub_srv_send_gpint_command(srv, cmd, 0, 30); > + > + if (status == DMUB_STATUS_OK) { > + status = dmub_srv_get_gpint_response(srv, (u32 *) &raw); > + > + if (status != DMUB_STATUS_OK) > + return -ETIMEDOUT; > + } else { > + return -ETIMEDOUT; > + } > + > + usleep_range(100, 1000); > + > + cmd++; > + res |= (raw << shift); > + shift += 16; > + i++; > + } > + > + *val = res; > + > + return 0; > +} > + > +DEFINE_DEBUGFS_ATTRIBUTE(dmub_trace_mask_fops, dmub_trace_mask_show, > + dmub_trace_mask_set, "0x%llx\n"); > + > /* > * Set dmcub trace event IRQ enable or disable. > * Usage to enable dmcub trace event IRQ: echo 1 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en > @@ -3880,6 +3968,9 @@ void dtn_debugfs_init(struct amdgpu_device *adev) > debugfs_create_file_unsafe("amdgpu_dm_force_timing_sync", 0644, root, > adev, &force_timing_sync_ops); > > + debugfs_create_file_unsafe("amdgpu_dm_dmub_trace_mask", 0644, root, > + adev, &dmub_trace_mask_fops); > + > debugfs_create_file_unsafe("amdgpu_dm_dmcub_trace_event_en", 0644, root, > adev, &dmcub_trace_event_state_fops); > > diff --git a/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h b/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h > index ed4379c04715..aa6e6923afed 100644 > --- a/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h > +++ b/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h > @@ -818,18 +818,54 @@ enum dmub_gpint_command { > * RETURN: Lower 32-bit mask. > */ > DMUB_GPINT__UPDATE_TRACE_BUFFER_MASK = 101, > + > /** > - * DESC: Updates the trace buffer lower 32-bit mask. > + * DESC: Updates the trace buffer mask bit0~bit15. > * ARGS: The new mask > * RETURN: Lower 32-bit mask. > */ > DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD0 = 102, > + > /** > - * DESC: Updates the trace buffer mask bi0~bit15. > + * DESC: Updates the trace buffer mask bit16~bit31. > * ARGS: The new mask > * RETURN: Lower 32-bit mask. > */ > DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD1 = 103, > + > + /** > + * DESC: Updates the trace buffer mask bit32~bit47. > + * ARGS: The new mask > + * RETURN: Lower 32-bit mask. > + */ > + DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD2 = 114, > + > + /** > + * DESC: Updates the trace buffer mask bit48~bit63. > + * ARGS: The new mask > + * RETURN: Lower 32-bit mask. > + */ > + DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD3 = 115, > + > + /** > + * DESC: Read the trace buffer mask bi0~bit15. > + */ > + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD0 = 116, > + > + /** > + * DESC: Read the trace buffer mask bit16~bit31. > + */ > + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD1 = 117, > + > + /** > + * DESC: Read the trace buffer mask bi32~bit47. > + */ > + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD2 = 118, > + > + /** > + * DESC: Updates the trace buffer mask bit32~bit63. > + */ > + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD3 = 119, > }; > > /**
diff --git a/Documentation/gpu/amdgpu/display/dc-debug.rst b/Documentation/gpu/amdgpu/display/dc-debug.rst index 40c55a618918..817631b1dbf3 100644 --- a/Documentation/gpu/amdgpu/display/dc-debug.rst +++ b/Documentation/gpu/amdgpu/display/dc-debug.rst @@ -75,3 +75,44 @@ change in real-time by using something like:: When reporting a bug related to DC, consider attaching this log before and after you reproduce the bug. + +DMUB Firmware Debug +=================== + +Sometimes, dmesg logs aren't enough. This is especially true if a feature is +implemented primarily in DMUB firmware. In such cases, all we see in dmesg when +an issue arises is some generic timeout error. So, to get more relevant +information, we can trace DMUB commands by enabling the relevant bits in +`amdgpu_dm_dmub_trace_mask`. + +Currently, we support the tracing of the following groups: + +Trace Groups +------------ + +.. csv-table:: + :header-rows: 1 + :widths: 1, 1 + :file: ./trace-groups-table.csv + +**Note: Not all ASICs support all of the listed trace groups** + +So, to enable just PSR tracing you can use the following command:: + + # echo 0x8020 > /sys/kernel/debug/dri/0/amdgpu_dm_dmub_trace_mask + +Then, you need to enable logging trace events to the buffer, which you can do +using the following:: + + # echo 1 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en + +Lastly, after you are able to reproduce the issue you are trying to debug, +you can disable tracing and read the trace log by using the following:: + + # echo 0 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en + # cat /sys/kernel/debug/dri/0/amdgpu_dm_dmub_tracebuffer + +So, when reporting bugs related to features such as PSR and ABM, consider +enabling the relevant bits in the mask before reproducing the issue and +attach the log that you obtain from the trace buffer in any bug reports that you +create. diff --git a/Documentation/gpu/amdgpu/display/trace-groups-table.csv b/Documentation/gpu/amdgpu/display/trace-groups-table.csv new file mode 100644 index 000000000000..3f6a50d1d883 --- /dev/null +++ b/Documentation/gpu/amdgpu/display/trace-groups-table.csv @@ -0,0 +1,29 @@ +Name, Mask Value +INFO, 0x1 +IRQ SVC, 0x2 +VBIOS, 0x4 +REGISTER, 0x8 +PHY DBG, 0x10 +PSR, 0x20 +AUX, 0x40 +SMU, 0x80 +MALL, 0x100 +ABM, 0x200 +ALPM, 0x400 +TIMER, 0x800 +HW LOCK MGR, 0x1000 +INBOX1, 0x2000 +PHY SEQ, 0x4000 +PSR STATE, 0x8000 +ZSTATE, 0x10000 +TRANSMITTER CTL, 0x20000 +PANEL CNTL, 0x40000 +FAMS, 0x80000 +DPIA, 0x100000 +SUBVP, 0x200000 +INBOX0, 0x400000 +SDP, 0x4000000 +REPLAY, 0x8000000 +REPLAY RESIDENCY, 0x20000000 +CURSOR INFO, 0x80000000 +IPS, 0x100000000 diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c index 13a177d34376..06a73f283e9d 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c @@ -2971,6 +2971,94 @@ static int allow_edp_hotplug_detection_set(void *data, u64 val) return 0; } +static int dmub_trace_mask_set(void *data, u64 val) +{ + struct amdgpu_device *adev = data; + struct dmub_srv *srv = adev->dm.dc->ctx->dmub_srv->dmub; + enum dmub_gpint_command cmd; + enum dmub_status status; + u64 mask = 0xffff; + u8 shift = 0; + u32 res; + int i; + + if (!srv->fw_version) + return -EINVAL; + + for (i = 0; i < 4; i++) { + res = (val & mask) >> shift; + + switch (i) { + case 0: + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD0; + break; + case 1: + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD1; + break; + case 2: + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD2; + break; + case 3: + cmd = DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD3; + break; + } + + status = dmub_srv_send_gpint_command(srv, cmd, res, 30); + + if (status != DMUB_STATUS_OK) + return -ETIMEDOUT; + + usleep_range(100, 1000); + + mask <<= 16; + shift += 16; + } + + return 0; +} + +static int dmub_trace_mask_show(void *data, u64 *val) +{ + enum dmub_gpint_command cmd = DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD0; + struct amdgpu_device *adev = data; + struct dmub_srv *srv = adev->dm.dc->ctx->dmub_srv->dmub; + enum dmub_status status; + u8 shift = 0; + u64 raw = 0; + u64 res = 0; + int i = 0; + + if (!srv->fw_version) + return -EINVAL; + + while (i < 4) { + status = dmub_srv_send_gpint_command(srv, cmd, 0, 30); + + if (status == DMUB_STATUS_OK) { + status = dmub_srv_get_gpint_response(srv, (u32 *) &raw); + + if (status != DMUB_STATUS_OK) + return -ETIMEDOUT; + } else { + return -ETIMEDOUT; + } + + usleep_range(100, 1000); + + cmd++; + res |= (raw << shift); + shift += 16; + i++; + } + + *val = res; + + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(dmub_trace_mask_fops, dmub_trace_mask_show, + dmub_trace_mask_set, "0x%llx\n"); + /* * Set dmcub trace event IRQ enable or disable. * Usage to enable dmcub trace event IRQ: echo 1 > /sys/kernel/debug/dri/0/amdgpu_dm_dmcub_trace_event_en @@ -3880,6 +3968,9 @@ void dtn_debugfs_init(struct amdgpu_device *adev) debugfs_create_file_unsafe("amdgpu_dm_force_timing_sync", 0644, root, adev, &force_timing_sync_ops); + debugfs_create_file_unsafe("amdgpu_dm_dmub_trace_mask", 0644, root, + adev, &dmub_trace_mask_fops); + debugfs_create_file_unsafe("amdgpu_dm_dmcub_trace_event_en", 0644, root, adev, &dmcub_trace_event_state_fops); diff --git a/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h b/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h index ed4379c04715..aa6e6923afed 100644 --- a/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h +++ b/drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h @@ -818,18 +818,54 @@ enum dmub_gpint_command { * RETURN: Lower 32-bit mask. */ DMUB_GPINT__UPDATE_TRACE_BUFFER_MASK = 101, + /** - * DESC: Updates the trace buffer lower 32-bit mask. + * DESC: Updates the trace buffer mask bit0~bit15. * ARGS: The new mask * RETURN: Lower 32-bit mask. */ DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD0 = 102, + /** - * DESC: Updates the trace buffer mask bi0~bit15. + * DESC: Updates the trace buffer mask bit16~bit31. * ARGS: The new mask * RETURN: Lower 32-bit mask. */ DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD1 = 103, + + /** + * DESC: Updates the trace buffer mask bit32~bit47. + * ARGS: The new mask + * RETURN: Lower 32-bit mask. + */ + DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD2 = 114, + + /** + * DESC: Updates the trace buffer mask bit48~bit63. + * ARGS: The new mask + * RETURN: Lower 32-bit mask. + */ + DMUB_GPINT__SET_TRACE_BUFFER_MASK_WORD3 = 115, + + /** + * DESC: Read the trace buffer mask bi0~bit15. + */ + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD0 = 116, + + /** + * DESC: Read the trace buffer mask bit16~bit31. + */ + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD1 = 117, + + /** + * DESC: Read the trace buffer mask bi32~bit47. + */ + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD2 = 118, + + /** + * DESC: Updates the trace buffer mask bit32~bit63. + */ + DMUB_GPINT__GET_TRACE_BUFFER_MASK_WORD3 = 119, }; /**
For features that are implemented primarily in DMUB (e.g. PSR), it is useful to be able to trace them at a DMUB level from the kernel, especially when debugging issues. So, introduce a debugfs interface that is able to read and set the DMUB trace mask dynamically at runtime and document how to use it. Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com> --- Documentation/gpu/amdgpu/display/dc-debug.rst | 41 +++++++++ .../gpu/amdgpu/display/trace-groups-table.csv | 29 ++++++ .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 91 +++++++++++++++++++ .../gpu/drm/amd/display/dmub/inc/dmub_cmd.h | 40 +++++++- 4 files changed, 199 insertions(+), 2 deletions(-) create mode 100644 Documentation/gpu/amdgpu/display/trace-groups-table.csv