NVIDIA Tegra
NVIDIA DRIVE OS 5.1 Linux

Developer Guide
5.1.0.2 Release


 
Triggering System State Transition from Linux
 
Receiving Partition State Transition Message
When Linux is configured as a System State Transition Privileged Guest, Linux can request a system state transition through its integrated drivers. On how to configure a guest as a privileged guest, please refer to Enabling a Guest OS to request System State Transition. This release contains the tegra_hv_pm_ctl driver for initiating a System State Transition. The driver must be configured with an IVC to System Manager to function correctly. For information on how to configure the driver, refer to its DTB documentation:
drive-oss-src/kernel/Documentation/devicetree/bindings/tegra_hv/tegra_hv_pm_ctl.txt
When configured correctly, tegra_hv_pm_ctl creates two nodes as its sysfs. Writing an ascii 1 will trigger the corresponding system state transition.
Privileged Guest must complete any communication with the Board Power State Management chipset before this request is made.
To trigger Timed Graceful System Shutdown
echo 1 > /sys/devices/tegra_hv_pm_ctl/trigger_sys_shutdown
To trigger Timed Graceful System Reboot
echo 1 > /sys/devices/tegra_hv_pm_ctl/trigger_sys_reboot
Receiving Partition State Transition Message
This release contains a userspace daemon to handle the Partition State Transition Message from SysMgr. For more information, see shutdown under General Utilities in Utilities. As the userspace daemon does not have a direct access to DTB, which contains a specification of the IVC channel number to SysMgr, the tegra_hv_pm_ctl driver provides a character device node for the userspace daemon. This allows the daemon to monitor the following location, regardless of the underlying channel number: /dev/tegra_hv_pm_ctl.