Documentation/ABI/stable/sysfs-driver-firmware-zynqmp
What: /sys/devices/platform/firmware\:zynqmp-firmware/ggs*
Date: March 2020
KernelVersion: 5.6
Contact: "Jolly Shah" <jollys@xilinx.com>
Description:
Read/Write PMU global general storage register value,
GLOBAL_GEN_STORAGE{0:3}.
Global general storage register that can be used
by system to pass information between masters.
The register is reset during system or power-on
resets. Three registers are used by the FSBL and
other Xilinx software products: GLOBAL_GEN_STORAGE{4:6}.
Usage::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/ggs0
# echo <value> > /sys/devices/platform/firmware\:zynqmp-firmware/ggs0
Example::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/ggs0
# echo 0x1234ABCD > /sys/devices/platform/firmware\:zynqmp-firmware/ggs0
Users: Xilinx
What: /sys/devices/platform/firmware\:zynqmp-firmware/pggs*
Date: March 2020
KernelVersion: 5.6
Contact: "Jolly Shah" <jollys@xilinx.com>
Description:
Read/Write PMU persistent global general storage register
value, PERS_GLOB_GEN_STORAGE{0:3}.
Persistent global general storage register that
can be used by system to pass information between
masters.
This register is only reset by the power-on reset
and maintains its value through a system reset.
Four registers are used by the FSBL and other Xilinx
software products: PERS_GLOB_GEN_STORAGE{4:7}.
Register is reset only by a POR reset.
Usage::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/pggs0
# echo <value> > /sys/devices/platform/firmware\:zynqmp-firmware/pggs0
Example::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/pggs0
# echo 0x1234ABCD > /sys/devices/platform/firmware\:zynqmp-firmware/pggs0
Users: Xilinx
What: /sys/devices/platform/firmware\:zynqmp-firmware/shutdown_scope
Date: March 2020
KernelVersion: 5.6
Contact: "Jolly Shah" <jollys@xilinx.com>
Description:
This sysfs interface allows to set the shutdown scope for the
next shutdown request. When the next shutdown is performed, the
platform specific portion of PSCI-system_off can use the chosen
shutdown scope.
Following are available shutdown scopes(subtypes):
subsystem:
Only the APU along with all of its peripherals
not used by other processing units will be
shut down. This may result in the FPD power
domain being shut down provided that no other
processing unit uses FPD peripherals or DRAM.
ps_only:
The complete PS will be shut down, including the
RPU, PMU, etc. Only the PL domain (FPGA)
remains untouched.
system:
The complete system/device is shut down.
Usage::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/shutdown_scope
# echo <scope> > /sys/devices/platform/firmware\:zynqmp-firmware/shutdown_scope
Example::
# cat /sys/devices/platform/firmware\:zynqmp-firmware/shutdown_scope
# echo "subsystem" > /sys/devices/platform/firmware\:zynqmp-firmware/shutdown_scope
Users: Xilinx
What: /sys/devices/platform/firmware\:zynqmp-firmware/health_status
Date: March 2020
KernelVersion: 5.6
Contact: "Jolly Shah" <jollys@xilinx.com>
Description:
This sysfs interface allows to set the health status. If PMUFW
is compiled with CHECK_HEALTHY_BOOT, it will check the healthy
bit on FPD WDT expiration. If healthy bit is set by a user
application running in Linux, PMUFW will do APU only restart. If
healthy bit is not set during FPD WDT expiration, PMUFW will do
system restart.
Usage:
Set healthy bit::
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/health_status
Unset healthy bit::
# echo 0 > /sys/devices/platform/firmware\:zynqmp-firmware/health_status
Users: Xilinx
What: /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
Date: Feb 2022
KernelVersion: 5.18
Contact: "Ronak Jain" <ronak.jain@xilinx.com>
Description:
This sysfs interface allows user to configure features at
runtime. The user can enable or disable features running at
firmware as well as the user can configure the parameters of
the features at runtime. The supported features are over
temperature and external watchdog. Here, the external watchdog
is completely different than the /dev/watchdog as the external
watchdog is running on the firmware and it is used to monitor
the health of firmware not APU(Linux). Also, the external
watchdog is interfaced outside of the zynqmp soc.
The supported config ids are for the feature configuration is,
1. PM_FEATURE_OVERTEMP_STATUS = 1, the user can enable or
disable the over temperature feature.
2. PM_FEATURE_OVERTEMP_VALUE = 2, the user can configure the
over temperature limit in Degree Celsius.
3. PM_FEATURE_EXTWDT_STATUS = 3, the user can enable or disable
the external watchdog feature.
4. PM_FEATURE_EXTWDT_VALUE = 4, the user can configure the
external watchdog feature.
Usage:
Select over temperature config ID to enable/disable feature
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
Check over temperature config ID is selected or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
The expected result is 1.
Select over temperature config ID to configure OT limit
# echo 2 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
Check over temperature config ID is selected or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
The expected result is 2.
Select external watchdog config ID to enable/disable feature
# echo 3 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
Check external watchdog config ID is selected or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
The expected result is 3.
Select external watchdog config ID to configure time interval
# echo 4 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
Check external watchdog config ID is selected or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
The expected result is 4.
Users: Xilinx
What: /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Date: Feb 2022
KernelVersion: 5.18
Contact: "Ronak Jain" <ronak.jain@xilinx.com>
Description:
This sysfs interface allows to configure features at runtime.
The user can enable or disable features running at firmware.
Also, the user can configure the parameters of the features
at runtime. The supported features are over temperature and
external watchdog. Here, the external watchdog is completely
different than the /dev/watchdog as the external watchdog is
running on the firmware and it is used to monitor the health
of firmware not APU(Linux). Also, the external watchdog is
interfaced outside of the zynqmp soc.
By default the features are disabled in the firmware. The user
can enable features by querying appropriate config id of the
features.
The default limit for the over temperature is 90 Degree Celsius.
The default timer interval for the external watchdog is 570ms.
The supported config ids are for the feature configuration is,
1. PM_FEATURE_OVERTEMP_STATUS = 1, the user can enable or
disable the over temperature feature.
2. PM_FEATURE_OVERTEMP_VALUE = 2, the user can configure the
over temperature limit in Degree Celsius.
3. PM_FEATURE_EXTWDT_STATUS = 3, the user can enable or disable
the external watchdog feature.
4. PM_FEATURE_EXTWDT_VALUE = 4, the user can configure the
external watchdog feature.
Usage:
Enable over temperature feature
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the over temperature feature is enabled or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 1.
Disable over temperature feature
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 0 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the over temperature feature is disabled or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 0.
Configure over temperature limit to 50 Degree Celsius
# echo 2 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 50 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the over temperature limit is configured or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 50.
Enable external watchdog feature
# echo 3 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 1 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the external watchdog feature is enabled or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 1.
Disable external watchdog feature
# echo 3 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 0 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the external watchdog feature is disabled or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 0.
Configure external watchdog timer interval to 500ms
# echo 4 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_id
# echo 500 > /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
Check whether the external watchdog timer interval is configured or not
# cat /sys/devices/platform/firmware\:zynqmp-firmware/feature_config_value
The expected result is 500.
Users: Xilinx