Currently, gpu_metrics is exported a binary blob with the defintion provided by means of a structure and version. Though providing the version works well for backward compatiblity, it doesn't work the other way for tools like amd-smi. Installing a driver with a newer definition of gpu_metrics sometimes could break compatibility with the older version of amd-smi. Even if newer fields are added towards the end, a change in datatype of existing field or an increase of size in an array element will break the compatiblity.
To address this, add field encoding before each metrics field. Each field is designated an attribute id, and along with that the type (only integral ones are used currently) and number of instances are encoded. Thus an older amd-smi tool may skip any unknown attribute field, and move to the next attribute. This encoding scheme doesn't take care of elements that are not valid always - say member_field[3] is not valid under certain conditions in an array member member_field[10]. Hence this still keeps the design of having all invalid elements initialized to 0xFFs. Lijo Lazar (7): drm/amdgpu/pm: Add definition for gpu_metrics v1.9 drm/amd/pm: Add helper functions for gpu metrics drm/amd/pm: Use gpu metrics 1.9 for SMUv13.0.6 drm/amd/pm: Use gpu metrics 1.9 for SMUv13.0.12 drm/amd/pm: Add schema v1.1 for parition metrics drm/amd/pm: Update SMUv13.0.6 partition metrics drm/amd/pm: Update SMUv13.0.12 partition metrics .../gpu/drm/amd/include/kgd_pp_interface.h | 123 ++++++++++++++ .../drm/amd/pm/swsmu/smu13/smu_v13_0_12_ppt.c | 94 +++++------ .../drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c | 140 ++++++++-------- .../drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.h | 156 +++++++++++++++++- drivers/gpu/drm/amd/pm/swsmu/smu_cmn.h | 62 +++++++ 5 files changed, 450 insertions(+), 125 deletions(-) -- 2.49.0
