On Mon, Dec 9, 2019 at 8:29 AM Robin Murphy <robin.murphy@xxxxxxx> wrote:
On 06/12/2019 6:45 pm, Anand Moon wrote:Since ATF is operating completely in volatile memory, and shouldn't be
Most of the RK3399 SBC boards do not perform cleanFWIW reboot problems on RK3399 have been tracked down to issues in
shutdown and clean reboot.
upstream ATF, and are unrelated to the PMIC.
These patches try to help resolve the issue with properAs mentioned elsewhere, although this is what the BSP kernel seems to
shutdown by turning off the PMIC.
do, and in practice it's unlikely to matter for the majority of devboard
users like you and me, I still feel a bit uncomfortable with this
solution for systems using ATF as in principle the secure world might
want to know about orderly shutdowns, and this effectively makes every
shutdown an unexpected power loss from secure software's point of view.
touching hardware once it passes off control to the kernel anyways,
what is the harm of pulling the rug out from under it?
If this idea is to prevent issues in the future, such as if ATF does
gain the ability to preempt hardware control, then at that time ATF
will need to be able to handle actually powering off devices using the
But as we discussed previously, ATF doesn't have this capability, so
in this case any board without a dedicated power-off gpio will be
unable to power off at all.
Also it seems that giving ATF this functionality, with the current
state of ATF, would be cost prohibitive.
I personally feel that allowing the kernel to do this is a solution to
the problem we have now.