On 17:58-20230824, Tom Rini wrote:
On Thu, Aug 24, 2023 at 11:53:17PM +0200, Jan Kiszka wrote:
From: Jan Kiszka jan.kiszka@siemens.com
At this point, system shutdown is not supported by the DM firmware that TF-A calls. As we can't de-select only this feature, declare complete PSCI reset support as non-functional so that we don't signal incomplete support to the OS via EFI runtime services. This makes power-off under Linux work again when booting via EFI.
Signed-off-by: Jan Kiszka jan.kiszka@siemens.com
board/ti/am62x/beagleplay_a53.config | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/board/ti/am62x/beagleplay_a53.config b/board/ti/am62x/beagleplay_a53.config index 967f794446d..8b0f671bc9e 100644 --- a/board/ti/am62x/beagleplay_a53.config +++ b/board/ti/am62x/beagleplay_a53.config @@ -53,3 +53,5 @@ CONFIG_SPI=n CONFIG_SPI_FLASH=n CONFIG_SPL_DM_SPI_FLASH=n CONFIG_SPL_SPI_FLASH_SUPPORT=n +# DM firmware lacks support for shutdown +# CONFIG_PSCI_RESET is not set
Is this lack of feature for just the beagleplay part of the firmware stack or more generically to the TI am62x platforms?
Thanks a ton Jan for digging deep into this and finding this. So much appreciated.
This is all K3 platforms with the exception of j7200-evm.
PSCI SYSTEM_OFF function is routed by TFA to DM, there is no implementation on DM side since involved PMIC and team is trying to lock in a manner in which it is easier for people to describe things.
PSCI SYSTEM_RESET on the other hand is handled correctly by DM.
Even though CONFIG_POWEROFF is disabled, apparently enabling PSCI_RESET results in EFI runtime services gets to think that poweroff is also supported. Looking at drivers/firmware/psci.c[1] efi request for poweroff is via EFI_RESET_SHUTDOWN[2] - so the specification itself mandates that both reset AND poweroff should be implemented.
Luckily for us we have a broken u-boot reset implementation, which last I looked was not following the h/w specifications and the intent was to move to PSCI -> DM for reset so that system can properly reset and not get randomly hung during reset under certain circumstances.
But, given the circumstances, I can pick this up and do it at am62_evm level rather than at just beagle level. I will pick this patch up and roll it up into v6 of the beagleplay series - but will modify am62x_evm config instead.
[1] https://github.com/u-boot/u-boot/blob/master/drivers/firmware/psci.c#L246 [2] https://uefi.org/specs/UEFI/2.9_A/08_Services_Runtime_Services.html?highligh...