1.. SPDX-License-Identifier: GPL-2.0-only
  2
  3Kernel driver Ampere(R)'s Altra(R) SMpro hwmon
  4==============================================
  5
  6Supported chips:
  7
  8  * Ampere(R) Altra(R)
  9
 10    Prefix: ``smpro``
 11
 12    Reference: `Altra SoC BMC Interface Specification`
 13
 14Author: Thu Nguyen <thu@os.amperecomputing.com>
 15
 16Description
 17-----------
 18The smpro-hwmon driver supports hardware monitoring for Ampere(R) Altra(R)
 19SoCs based on the SMpro co-processor (SMpro).  The following sensor metrics
 20are supported by the driver:
 21
 22  * temperature
 23  * voltage
 24  * current
 25  * power
 26
 27The interface provides the registers to query the various sensors and
 28their values which are then exported to userspace by this driver.
 29
 30Usage Notes
 31-----------
 32
 33The driver creates at least two sysfs files for each sensor.
 34
 35* ``<sensor_type><idx>_label`` reports the sensor label.
 36* ``<sensor_type><idx>_input`` returns the sensor value.
 37
 38The sysfs files are allocated in the SMpro rootfs folder, with one root
 39directory for each instance.
 40
 41When the SoC is turned off, the driver will fail to read registers and
 42return ``-ENXIO``.
 43
 44Sysfs entries
 45-------------
 46
 47The following sysfs files are supported:
 48
 49* Ampere(R) Altra(R):
 50
 51  ============    =============  ======  ===============================================
 52  Name            Unit           Perm    Description
 53  ============    =============  ======  ===============================================
 54  temp1_input     millicelsius   RO      SoC temperature
 55  temp2_input     millicelsius   RO      Max temperature reported among SoC VRDs
 56  temp2_crit      millicelsius   RO      SoC VRD HOT Threshold temperature
 57  temp3_input     millicelsius   RO      Max temperature reported among DIMM VRDs
 58  temp4_input     millicelsius   RO      Max temperature reported among Core VRDs
 59  temp5_input     millicelsius   RO      Temperature of DIMM0 on CH0
 60  temp5_crit      millicelsius   RO      MEM HOT Threshold for all DIMMs
 61  temp6_input     millicelsius   RO      Temperature of DIMM0 on CH1
 62  temp6_crit      millicelsius   RO      MEM HOT Threshold for all DIMMs
 63  temp7_input     millicelsius   RO      Temperature of DIMM0 on CH2
 64  temp7_crit      millicelsius   RO      MEM HOT Threshold for all DIMMs
 65  temp8_input     millicelsius   RO      Temperature of DIMM0 on CH3
 66  temp8_crit      millicelsius   RO      MEM HOT Threshold for all DIMMs
 67  temp9_input     millicelsius   RO      Temperature of DIMM0 on CH4
 68  temp9_crit      millicelsius   RO      MEM HOT Threshold for all DIMMs
 69  temp10_input    millicelsius   RO      Temperature of DIMM0 on CH5
 70  temp10_crit     millicelsius   RO      MEM HOT Threshold for all DIMMs
 71  temp11_input    millicelsius   RO      Temperature of DIMM0 on CH6
 72  temp11_crit     millicelsius   RO      MEM HOT Threshold for all DIMMs
 73  temp12_input    millicelsius   RO      Temperature of DIMM0 on CH7
 74  temp12_crit     millicelsius   RO      MEM HOT Threshold for all DIMMs
 75  temp13_input    millicelsius   RO      Max temperature reported among RCA VRDs
 76  in0_input       millivolts     RO      Core voltage
 77  in1_input       millivolts     RO      SoC voltage
 78  in2_input       millivolts     RO      DIMM VRD1 voltage
 79  in3_input       millivolts     RO      DIMM VRD2 voltage
 80  in4_input       millivolts     RO      RCA VRD voltage
 81  cur1_input      milliamperes   RO      Core VRD current
 82  cur2_input      milliamperes   RO      SoC VRD current
 83  cur3_input      milliamperes   RO      DIMM VRD1 current
 84  cur4_input      milliamperes   RO      DIMM VRD2 current
 85  cur5_input      milliamperes   RO      RCA VRD current
 86  power1_input    microwatts     RO      Core VRD power
 87  power2_input    microwatts     RO      SoC VRD power
 88  power3_input    microwatts     RO      DIMM VRD1 power
 89  power4_input    microwatts     RO      DIMM VRD2 power
 90  power5_input    microwatts     RO      RCA VRD power
 91  ============    =============  ======  ===============================================
 92
 93  Example::
 94
 95    # cat in0_input
 96    830
 97    # cat temp1_input
 98    37000
 99    # cat curr1_input
100    9000
101    # cat power5_input
102    19500000