implement mechanism to reset PMIC

[xypron]

In the device-tree we have a node with compatible gpio-restart.

                gpiorst:gpio-restart {
                        compatible = "gpio-restart";
                        gpios = <&gpio 63 GPIO_ACTIVE_HIGH>;
                };

Why is CONFIG_SYSRESET_GPIO not selected to make use of it?

[jonathangray]

See starfive-tech/Fedora_on_StarFive#25
Despite the device tree and code in the U-Boot and OpenSBI branches it appears that reset only works when talking to the PMIC over I2C or pushing the button next to the USB-C power which is connected to the PMIC.

[pdp7]

please see comment here from @MichaelZhuxx
starfive-tech/Fedora_on_StarFive#25 (comment)

[xypron]

This issue was about U-Boot. It is good that we found out how to make a reset work in Linux.
But we also want the reset command in U-Boot to work. So we shoudn't close this issue.

The best solution would be to implement the reset in OpenSBI.

[pdp7]

@xypron thank you for pointing that out and re-opening

[MichaelZhuxx]

@pdp7 yes, that's my concern in todays weekly meeting, we need merge its same way(tell the pmic to reset the whole system) from linux to u-boot. @tekkamanninja please try to fix it. then I can offically release a u-boot binary. thanks.

[xypron]

@MichaelZhuxx
The system reset should only be implemented once and that is in OpenSBI. U-Boot and Linux should call the system reset extension. This just like ARM does with PSCI.

[MichaelZhuxx]

@xypron good point. I think that's the best way. @tekkamanninja what's your opinion?

[MichaelZhuxx]

starfive-tech/opensbi@b5facf9
yes, we have done same method in openSBI to enable the system reset by GPIO63. now we should implement it by I2C.

[pdp7]

starfive-tech/opensbi@b5facf9
yes, we have done same method in openSBI to enable the system reset by GPIO63. now we should implement it by I2C.

Yes, the does seem ideal to implement restarting PMIC via I2C in OpenSBI so that SBI reset will work.