1*bd5d9c74SNayna JainWhat: /sys/firmware/secvar 2*bd5d9c74SNayna JainDate: August 2019 3*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 4*bd5d9c74SNayna JainDescription: This directory is created if the POWER firmware supports OS 5*bd5d9c74SNayna Jain secureboot, thereby secure variables. It exposes interface 6*bd5d9c74SNayna Jain for reading/writing the secure variables 7*bd5d9c74SNayna Jain 8*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/vars 9*bd5d9c74SNayna JainDate: August 2019 10*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 11*bd5d9c74SNayna JainDescription: This directory lists all the secure variables that are supported 12*bd5d9c74SNayna Jain by the firmware. 13*bd5d9c74SNayna Jain 14*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/format 15*bd5d9c74SNayna JainDate: August 2019 16*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 17*bd5d9c74SNayna JainDescription: A string indicating which backend is in use by the firmware. 18*bd5d9c74SNayna Jain This determines the format of the variable and the accepted 19*bd5d9c74SNayna Jain format of variable updates. 20*bd5d9c74SNayna Jain 21*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/vars/<variable name> 22*bd5d9c74SNayna JainDate: August 2019 23*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 24*bd5d9c74SNayna JainDescription: Each secure variable is represented as a directory named as 25*bd5d9c74SNayna Jain <variable_name>. The variable name is unique and is in ASCII 26*bd5d9c74SNayna Jain representation. The data and size can be determined by reading 27*bd5d9c74SNayna Jain their respective attribute files. 28*bd5d9c74SNayna Jain 29*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/vars/<variable_name>/size 30*bd5d9c74SNayna JainDate: August 2019 31*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 32*bd5d9c74SNayna JainDescription: An integer representation of the size of the content of the 33*bd5d9c74SNayna Jain variable. In other words, it represents the size of the data. 34*bd5d9c74SNayna Jain 35*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/vars/<variable_name>/data 36*bd5d9c74SNayna JainDate: August 2019 37*bd5d9c74SNayna JainContact: Nayna Jain h<nayna@linux.ibm.com> 38*bd5d9c74SNayna JainDescription: A read-only file containing the value of the variable. The size 39*bd5d9c74SNayna Jain of the file represents the maximum size of the variable data. 40*bd5d9c74SNayna Jain 41*bd5d9c74SNayna JainWhat: /sys/firmware/secvar/vars/<variable_name>/update 42*bd5d9c74SNayna JainDate: August 2019 43*bd5d9c74SNayna JainContact: Nayna Jain <nayna@linux.ibm.com> 44*bd5d9c74SNayna JainDescription: A write-only file that is used to submit the new value for the 45*bd5d9c74SNayna Jain variable. The size of the file represents the maximum size of 46*bd5d9c74SNayna Jain the variable data that can be written. 47