topic How can i trigger a software reset from u-boot WITHOUT using watchdog timer? in i.MX Processors

How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

aasheesh — Fri, 08 May 2015 11:26:22 GMT

Please let me know how to trigger a software reset from u-boot without using watchdog timer.

Re: How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

igorpadykov — Sat, 09 May 2015 00:53:26 GMT

Hi aasheesh

one can use WCR_SRS bit : writing to &wdog->wcr in

u-boot/imx_watchdog.c at master · mripard/u-boot · GitHub

WDOGx_WCR, SRS - Software Reset Signal,

sect.70.7.1 Watchdog Control Register (WDOGx_WCR) IMX6DQRM

Best regards

igor

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Re: How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

aasheesh — Mon, 11 May 2015 04:55:23 GMT

Thank you for your prompt reply.But in my board the watchdog is not connected to the PMIC. So,even if i set the WCR_SRS bit,i think it will not do a reset.Is there any alternative method which does not use watchdog like maybe SRC register or something like that.

Re: How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

igorpadykov — Mon, 11 May 2015 07:30:04 GMT

WCR_SRS will reset processor without usage of PMIC.

Re: How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

aasheesh — Fri, 15 May 2015 06:03:55 GMT

Thank you.By deasserting the SRS bit,my reset works.However,I must first disable warm_reset_enable bit in SRC_SCR register.The problem in my board was that WDOG_B was not connected to PMIC,so a watchdog timeout will not reset the PMIC. I have made an observation.Please let me know whether i am correct.I think deasserting the SRS bit creates a warm reset but as my warm_reset_enable bit is disabled,all warm reset sources must generate a cold reset.Hence my warm reset is actually creating a cold reset.Is it correct?Thank you for your assistance. Looking forward for your reply.

Re: How can i trigger a software reset from u-boot WITHOUT using watchdog timer?

igorpadykov — Fri, 15 May 2015 08:16:20 GMT

I think your understanding is right.