proto/nvme_features.proto

syntax = "proto3";

package google.gbmc.nvme.base;

// 01h - Arbitration
// This feature controls the arbitration of commands among different submission queues.
message Arbitration {
  // Bit 7:0 - Arbitration Burst (AB)
  // Specifies the maximum number of commands that the controller may launch at one time from a particular submission queue.
  uint32 arbitration_burst = 1;
  // Bit 15:8 - Low Priority Weight (LPW)
  // Specifies the number of commands that may be executed from the low priority service class in each round.
  uint32 low_priority_weight = 2;
  // Bit 23:16 - Medium Priority Weight (MPW)
  // Specifies the number of commands that may be executed from the medium priority service class in each round.
  uint32 medium_priority_weight = 3;
  // Bit 31:24 - High Priority Weight (HPW)
  // Specifies the number of commands that may be executed from the high priority service class in each round.
  uint32 high_priority_weight = 4;
}

// 02h - Power Management
// This feature allows the host to configure the power state of the controller.
message PowerManagement {
  // Bit 4:0 - Power State (PS)
  // Specifies the power state that the controller should transition to.
  uint32 power_state = 1;
  // Bit 8 - Workload Hint (WH)
  // Indicates the type of workload that the controller should optimize for.
  uint32 workload_hint = 2;
}

// 04h - Temperature Threshold
// This feature allows the host to set temperature thresholds for the controller or a specific namespace.
message TemperatureThreshold {
  enum ThresholdType {
    OVER_TEMPERATURE = 0;
    UNDER_TEMPERATURE = 1;
  }
  // Bit 15:00 - Temperature Threshold (TMPTH)
  // Specifies the threshold value in Kelvins.
  uint32 temperature_threshold = 1;
  // Bit 19:16 - Threshold Temperature Select (TMPSEL)
  // Selects the temperature sensor.
  uint32 threshold_temperature_select = 2;
  // Bit 21:20 - Threshold Type Select (THSEL)
  // Selects the type of temperature threshold (Over, Under).
  ThresholdType threshold_type_select = 3;
}

// 05h - Error Recovery
// This feature controls the error recovery settings for the NVM command set.
message ErrorRecovery {
  enum State {
    DISABLED = 0;
    ENABLED = 1;
  }
  // Bit 15:00 - Time Limited Error Recovery (TLER)
  // Indicates a limited retry timeout value in 100 millisecond units.
  uint32 tler = 1;
  // Bit 16 - Deallocated or Unwritten Logical Block Error Enable (DULBE)
  // If set to ENABLED, then the Deallocated or Unwritten Logical Block error is enabled.
  State dulbe_enable = 2;
}

// 06h - Volatile Write Cache
// This feature controls the operation of the volatile write cache, if present.
message VolatileWriteCache {
  enum State {
    DISABLED = 0;
    ENABLED = 1;
  }
  // Bit 0 - Volatile Write Cache Enable (WCE)
  // If set to ENABLED, the volatile write cache is enabled.
  State write_cache_enable = 1;
}

// 07h - Number of Queues
// This feature configures the number of submission and completion queues.
message NumberOfQueues {
  // Bit 15:00 - Number of Submission Queues (NSQR)
  // Specifies the number of I/O submission queues requested by the host.
  uint32 number_of_submission_queues = 1;
  // Bit 31:16 - Number of Completion Queues (NCQR)
  // Specifies the number of I/O completion queues requested by the host.
  uint32 number_of_completion_queues = 2;
}

// 08h - Interrupt Coalescing
// This feature controls the interrupt coalescing settings.
message InterruptCoalescing {
  // Bit 7:0 - Aggregation Threshold (THR)
  // Specifies the minimum number of completion queue entries to aggregate before signaling an interrupt.
  uint32 aggregation_threshold = 1;
  // Bit 15:8 - Aggregation Time (TIME)
  // Specifies the maximum time to aggregate interrupts in units of 100 microseconds.
  uint32 aggregation_time = 2;
}

// 09h - Interrupt Vector Configuration
// This feature configures a specific interrupt vector.
message InterruptVectorConfiguration {
  enum CoalescingState {
    COALESCING_ENABLED = 0;
    COALESCING_DISABLED = 1;
  }
  // Bit 15:00 - Interrupt Vector (IV)
  // Specifies the interrupt vector to be configured.
  uint32 interrupt_vector = 1;
  // Bit 16 - Coalescing Disable (CD)
  // If set to COALESCING_DISABLED, interrupt coalescing is disabled for this vector.
  CoalescingState coalescing_disable = 2;
}

// 0Ah - Write Atomicity Normal
// This feature controls the write atomicity settings for normal write operations.
message WriteAtomicityNormal {
  enum NormalWriteAtomicityState {
    NORMAL_WRITE_ATOMICITY_ENABLED = 0;
    NORMAL_WRITE_ATOMICITY_DISABLED = 1;
  }
  // Bit 0 - Disable Normal (DN)
  // If set to NORMAL_WRITE_ATOMICITY_DISABLED, the controller shall disable normal write atomicity.
  NormalWriteAtomicityState disable_normal = 1;
}

// 0Bh - Asynchronous Event Configuration
// This feature controls the configuration of asynchronous events.
message AsynchronousEventConfiguration {
  enum EventState {
    EVENT_DISABLED = 0;
    EVENT_ENABLED = 1;
  }
  // Bit 7:0 - SMART / Health Critical Warnings
  // Specifies which SMART/Health critical warnings should trigger an asynchronous event notification.
  uint32 smart_critical_warning_config = 1;
  // Bit 8 - Namespace Attribute Notices
  EventState namespace_attribute_notice_config = 2;
  // Bit 9 - Firmware Activation Notices
  EventState fw_activation_notice_config = 3;
  // Bit 10 - Telemetry Log Notices
  EventState telemetry_log_notice_config = 4;
  // Bit 11 - Asymmetric Namespace Access Change Notices
  EventState asymmetric_namespace_access_change_config = 5;
  // Bit 12 - Predictable Latency Event Aggregate Log Change Notices
  EventState predictable_latency_event_aggregate_log_change_config = 6;
  // Bit 13 - LBA Status Information Alert Notices
  EventState lba_status_information_alert_config = 7;
  // Bit 14 - Endurance Group Event Aggregate Log Change Notices
  EventState endurance_group_event_aggregate_log_change_config = 8;
  // Bit 15 - Normal NVM Subsystem Shutdown
  EventState normal_nvm_subsystem_shutdown_config = 9;
  // Bit 27 - Zone Descriptor Changed Notices
  EventState zone_descriptor_changed_config = 10;
  // Bit 31 - Discovery Log Page Change Notification
  EventState discovery_log_page_change_config = 11;
}