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+What: /sys/devices/socX
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ The /sys/devices/ directory contains a sub-directory for each
+ System-on-Chip (SoC) device on a running platform. Information
+ regarding each SoC can be obtained by reading sysfs files. This
+ functionality is only available if implemented by the platform.
+
+ The directory created for each SoC will also house information
+ about devices which are commonly contained in /sys/devices/platform.
+ It has been agreed that if an SoC device exists, its supported
+ devices would be better suited to appear as children of that SoC.
+
+What: /sys/devices/socX/machine
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ Read-only attribute common to all SoCs. Contains the SoC machine
+ name (e.g. Ux500).
+
+What: /sys/devices/socX/family
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ Read-only attribute common to all SoCs. Contains SoC family name
+ (e.g. DB8500).
+
+ On many of ARM based silicon with SMCCC v1.2+ compliant firmware
+ this will contain the JEDEC JEP106 manufacturer’s identification
+ code. The format is "jep106:XXYY" where XX is identity code and
+ YY is continuation code.
+
+ This manufacturer’s identification code is defined by one
+ or more eight (8) bit fields, each consisting of seven (7)
+ data bits plus one (1) odd parity bit. It is a single field,
+ limiting the possible number of vendors to 126. To expand
+ the maximum number of identification codes, a continuation
+ scheme has been defined.
+
+ The specified mechanism is that an identity code of 0x7F
+ represents the "continuation code" and implies the presence
+ of an additional identity code field, and this mechanism
+ may be extended to multiple continuation codes followed
+ by the manufacturer's identity code.
+
+ For example, ARM has identity code 0x7F 0x7F 0x7F 0x7F 0x3B,
+ which is code 0x3B on the fifth 'page'. This is shortened
+ as JEP106 identity code of 0x3B and a continuation code of
+ 0x4 to represent the four continuation codes preceding the
+ identity code.
+
+What: /sys/devices/socX/serial_number
+Date: January 2019
+contact: Bjorn Andersson <bjorn.andersson@linaro.org>
+Description:
+ Read-only attribute supported by most SoCs. Contains the SoC's
+ serial number, if available.
+
+What: /sys/devices/socX/soc_id
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ Read-only attribute supported by most SoCs. In the case of
+ ST-Ericsson's chips this contains the SoC serial number.
+
+ On many of ARM based silicon with SMCCC v1.2+ compliant firmware
+ this will contain the SOC ID appended to the family attribute
+ to ensure there is no conflict in this namespace across various
+ vendors. The format is "jep106:XXYY:ZZZZ" where XX is identity
+ code, YY is continuation code and ZZZZ is the SOC ID.
+
+What: /sys/devices/socX/revision
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ Read-only attribute supported by most SoCs. Contains the SoC's
+ manufacturing revision number.
+
+What: /sys/devices/socX/process
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ Read-only attribute supported ST-Ericsson's silicon. Contains the
+ the process by which the silicon chip was manufactured.
+
+What: /sys/bus/soc
+Date: January 2012
+contact: Lee Jones <lee@kernel.org>
+Description:
+ The /sys/bus/soc/ directory contains the usual sub-folders
+ expected under most buses. /sys/bus/soc/devices is of particular
+ interest, as it contains a symlink for each SoC device found on
+ the system. Each symlink points back into the aforementioned
+ /sys/devices/socX devices.