meta-facebook: gc2-es: support DVT HSC sensor MP5998

[Joseph-Shih-ww]

Add MP5998 HSC (Hot Swap Controller) sensor support for DVT platform. (GC20T5T7-112)

[Motivation]

• DVT platform uses MP5998 as HSC instead of ADM1278
• Need to support both HSC modules (ADM1278 and MP5998) for different hardware revisions
• Enable runtime HSC module detection and proper sensor monitoring

[Design]

1. HSC Module Auto-Detection:

   • Add read_adm1278_model() to detect ADM1278/ADM1281 via PMBUS_MFR_MODEL
   • Add read_mp5990_model() to detect MP5998 (model string "8995")
   • Implement fallback detection logic in init_hsc_module()
   • Runtime HSC chip identification through PMBus interface

2. MP5998 Sensor Configuration:

   • I2C Bus: I2C_BUS2
   • I2C Address: 0x4C (0x98 >> 1)
   • Supported Sensors:
     • MB_HSC_TEMP_C (0xE): On-die temperature monitoring
     • MB_HSC_INPUT_VOLT_V (0x29): Input voltage monitoring * MB_HSC_OUTPUT_CURR_A (0x30): Output current monitoring * MB_HSC_INPUT_PWR_W (0x39): Input power monitoring

3. MP5998 Initialization Parameters: Note: Advanced calibration features are not configured in this step. Further tuning will be discussed with hardware team in future revisions.

   • iout_cal_gain: 0xFFFF (use chip default for RCS=2kΩ)
   • iout_oc_fault_limit: 0xFFFF (use chip default OCP threshold)
   • ocw_sc_ref: 0xFFFF (use chip default short-circuit reference)

4. Post-Read Processing Functions: MP5998 has different LSB resolution compared to MP5990 in our hardware configuration. Conversion factors are applied to match the actual hardware implementation.

   • post_mp5998_voltage_read(): * Converts voltage reading from original LSB (1/32 V) to actual LSB (1/64 V) * Conversion formula: val = val * 0.5 * This compensates for the different voltage divider ratio in DVT hardware

   • post_mp5998_power_read():

     • Converts power reading from original LSB (1 W) to actual LSB (0.5 W)
     • Conversion formula: val = val * 0.5 * This matches the power calculation with the actual current sensing configuration

[Test Result]

Verified on GC2-ES DVT platform with MP5998 HSC module. All sensors report correctly:

root@bmc-oob:~# sensor-util server --force | grep HSC
MB_HSC_TEMP_C (0xE) : 26.000 C
MB_HSC_INPUT_VOLT_V (0x29) : 12.250 Volts
MB_HSC_OUTPUT_CURR_A (0x30) : 0.180 Amps
MB_HSC_INPUT_PWR_W (0x39) : 1.450 Watts

[meta-codesync]

@facebook-github-bot has imported this pull request. If you are a Meta employee, you can view this in D92953326. (Because this pull request was imported automatically, there will not be any future comments.)

[meta-codesync]

@amithash merged this pull request in 0f1b47e.