tlbmc/fru_i2c.proto

// This is a experimental proto for BMC deterministic BMC code development
// Original proto is located at
// google3/experimental/users/anuraagb/i2c_experiment/i2c_bus.proto
edition = "2023";

package fru_i2c;

option java_multiple_files = true;
option java_outer_classname = "FruI2C";

// An I2C address is a combination of an address and an address length.
message I2CAddress {
  uint32 address = 1;
  enum AddressLength {
    ADDRESS_LENGTH_UNSPECIFIED = 0;
    // 7 bit addressing.
    ADDRESS_LENGTH_BIT7 = 1;
    // 10 bit addressing.
    ADDRESS_LENGTH_BIT10 = 2;
  }
  AddressLength address_length = 2;
}

message Bus {
  // The bus ID represents the bus number. For root buses, this is the kernel
  // bus number. For downstream buses, this is the bus number relative to the
  // mux.
  uint32 bus_id = 1;
  repeated Mux muxes = 2;
  repeated Eeprom eeproms = 3;
  repeated GpioController gpio_controllers = 4;
  repeated SensorComponent sensor_components = 5;
}

message Eeprom {
  // The model of the eeprom from
  string model = 1;
  // The node-local barepath of the eeprom resides on in alignment with
  // go/ecclesia-devpath.
  string barepath = 2;
  // The fixed address of the eeprom relative to the bus.
  I2CAddress address_identifier = 3;
  // Addressing mode of the eeprom.
  enum AddressingMode {
    ADDRESSING_MODE_UNSPECIFIED = 0;
    // 8-bit addressing mode. (Reversed to be compliant with enum naming)
    ADDRESSING_MODE_BIT8 = 1;
    // 16-bit addressing mode. (Reversed to be compliant with enum naming)
    ADDRESSING_MODE_BIT16 = 2;
  }
  AddressingMode addressing_mode = 4;

  // Size of the eeprom in bytes.
  uint32 size_bytes = 5;

  message PartInformation {
    string manufacturer = 1;
    string part_number = 2;
    string serial_number = 3;
  }
  PartInformation part_information = 6;
  // (tentative workaround for chassis rendering)This is introduced to support
  // the Probe:"FOUND('$some_board')" case in current EM probing logic only:
  // when the upstream board present, the downstream board has to be present
  // too.
  // The value will be the barepath..
  repeated string sub_boards = 7;
}

// A GPIO controller is a physical device that controls GPIOs. This is a
// controller that is connected to an I2C port.
message GpioController {
  // Unique identifier for the gpio within the bus topology.
  string name = 1;
  // The node-local barepath of the gpio resides on in alignment with
  // go/ecclesia-devpath.
  string barepath = 2;
  // The fixed address of the gpio relative to the bus.
  I2CAddress address_identifier = 3;
}

// A mux is a physical device that multiplexes multiple I2C buses from a single
// I2C bus.
message Mux {
  // Unique identifier for the mux within the bus topology.
  string switch_id = 1;
  // The model of the mux.
  string model = 2;
  // The node-local barepath of the mux resides on in alignment with
  // go/ecclesia-devpath.
  string barepath = 3;
  // The fixed address of the mux relative to the bus.
  I2CAddress address_identifier = 4;
  // The downstream buses that are connected to the mux.
  repeated Bus downstream_buses = 5;
}

// A sensor component is the physical device that is connected to an I2C port.
message SensorComponent {
  // Unique identifier for the sensor within the bus topology.
  string model = 1;
  // The node-local barepath of the sensor resides on in alignment with
  // go/ecclesia-devpath.
  string barepath = 2;
  // The fixed address of the sensor relative to the bus.
  I2CAddress address_identifier = 3;
}

message I2cRoot {
  string name = 1;
  repeated Bus buses = 2;
  // Chip SoC Model
  string chip_model = 3;
}