Best Regards! Anson Huang
-----Original Message----- From: Fabio Estevam [mailto:festevam@gmail.com] Sent: 2018-01-07 6:48 AM To: Anson Huang anson.huang@nxp.com Cc: Stefano Babic sbabic@denx.de; Fabio Estevam fabio.estevam@nxp.com; Albert ARIBAUD albert.u.boot@aribaud.net; Christian Gmeiner christian.gmeiner@gmail.com; Peng Fan peng.fan@nxp.com; U-Boot-Denx u-boot@lists.denx.de Subject: Re: [U-Boot] [PATCH V2] imx: mx7: psci: add system reset support
Hi Anson,
On Fri, Jan 5, 2018 at 4:25 AM, Anson Huang anson.huang@nxp.com wrote:
Thanks for the comments, the current reboot command works is just because wdog driver is enabled and when system reboot, the reboot notification callback in wdog driver will do reset. But if wdog is disabled in dtb, the reboot command will fail.
As now we use PSCI, the reboot operation will eventually call into u-boot's psci reset callback, we should support this feature, the reboot feature in Linux kernel should NOT depends on wdog's existence.
Ok, but what about erratum e10574 (Watchdog: A watchdog timeout or software trigger will not reset the SOC)?
According to this erratum WDOG_B pin needs to generate a system power on.
What should we do here? Writing 0x4 into WCR register will cause WDOG reset and WDOG_B will be asserted, if the board has WDOG_B connected to PMIC, then everything is right. Do you mean we need to handle the case of WDOG_B pin NOT connected to PMIC case? If the board has no such design, then the reset will be NOT safe using wdog.
Anson