amd
sbtsi: Add support to reporting SBTSI maximum HBM temperature
Add a new channel to support SBTSIx50 and SBTSIx54 for reporting maximum HBM temperature.
Test result on MI300C platform CPU temperature: $ cat /sys/bus/i3c/drivers/sbtsi_i3c/0-22400000001/hwmon/hwmon16/temp1_input 41750
Max HBM Temperature: $ cat /sys/bus/i3c/drivers/sbtsi_i3c/0-22400000001/hwmon/hwmon16/temp2_input 32000
Add the Label, Max and Min:
# cat temp1_label
CpuTemp
# cat temp1_input
42750
# cat temp1_max
98000
# cat temp1_min
0
# cat temp2_label
MaxMemTemp
# cat temp2_input
33000
# cat temp2_max
98000
# cat temp2_min
1000
Akshay, TSI registers 0x50 and 0x54 do not report any value on EPYC processors, SB-TSI driver has no way to know the platform to conditionally support the hwmon entries.
HBM temp information is available via APML, DIMM temp info is also available for EPYC processors, as SBRMI driver is aware of the platform via CPUID or simliar. can we expose hwmon entries for HBM/DIMM temp from SBRMI instead.
SBRMI through mailbox provides way to get the max HBM temp (highest of all stacks) using mailbox command 0xA1, will implement the required changes in SBRMI to support this.
