From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jr1ii-0006eD-FU for barebox@lists.infradead.org; Thu, 02 Jul 2020 16:05:53 +0000 Message-ID: From: Lucas Stach Date: Thu, 02 Jul 2020 18:05:48 +0200 In-Reply-To: <936755248.7359.1593703689870@mail.vodafone.de> References: <925732743.424285.1592919941556@mail.vodafone.de> <245646662.425432.1592925096458@mail.vodafone.de> <517310923.70062.1593427992397@mail.vodafone.de> <595dc8c8-09c8-81ad-d730-23781e207cbd@pengutronix.de> <429834562.114102.1593444620511@mail.vodafone.de> <1874617325.108865.1593446626706@mail.vodafone.de> <21c2fc40-e385-b05e-6392-55ad219597da@pengutronix.de> <1036676243.111725.1593448425601@mail.vodafone.de> <473645456.227984.1593597168773@mail.vodafone.de> <936755248.7359.1593703689870@mail.vodafone.de> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: reset / watchdog on an imx7d soc To: Giorgio Dal Molin , Ahmad Fatoum , Fabio Estevam Cc: Barebox List Hi Giorgio, Am Donnerstag, den 02.07.2020, 17:28 +0200 schrieb Giorgio Dal Molin: [...] > barebox does something similar to trigger the wdog but afterwards also calls > mdelay() and a printf() before falling in the endless loop: > > static void imx21_soc_reset(struct imx_wd *priv) > { > ... > imxwd_write(priv, IMX21_WDOG_WCR, val); > > /* Two additional writes due to errata ERR004346 */ > imxwd_write(priv, IMX21_WDOG_WCR, val); > imxwd_write(priv, IMX21_WDOG_WCR, val); > I'm not sure if the i.MX7 needs the same double write. Just in case, can you add a dummy read to the IMX21_WDOG_WCR register after the writes to make sure the writes actually get flushed to the device before the delay? Regards, Lucas > ... > > mdelay(1000); > > hang(); // <== this also calls printf() before for(;;); > > > What I've found is that if I put the endless loop right at the end of > imx21_soc_reset(), after the imxwd_write's, then the reboot process becomes > reliable. > > (The changes in the DCD with the addition of the write: > > wm 32 0x30391000 0x00000003 > > at the beginning, before the write: > > wm 32 0x30391000 0x00000002 > > are also essential, only the delay between the two seems to be not a big deal). > > giorgio > > > > giorgio > > > > > > > _______________________________________________ > > > > barebox mailing list > > > > barebox@lists.infradead.org > > > > http://lists.infradead.org/mailman/listinfo/barebox > > > > -- > > Pengutronix e.K. | | > > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | > > > > _______________________________________________ > > barebox mailing list > > barebox@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/barebox > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox