From owner-svn-src-head@freebsd.org Tue Jan 24 02:09:31 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id DA773CBEE63; Tue, 24 Jan 2017 02:09:31 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id AA293BC9; Tue, 24 Jan 2017 02:09:31 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v0O29Uk8047839; Tue, 24 Jan 2017 02:09:30 GMT (envelope-from ian@FreeBSD.org) Received: (from ian@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v0O29UDD047838; Tue, 24 Jan 2017 02:09:30 GMT (envelope-from ian@FreeBSD.org) Message-Id: <201701240209.v0O29UDD047838@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: ian set sender to ian@FreeBSD.org using -f From: Ian Lepore Date: Tue, 24 Jan 2017 02:09:30 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r312679 - head/sys/arm/freescale/imx X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Jan 2017 02:09:32 -0000 Author: ian Date: Tue Jan 24 02:09:30 2017 New Revision: 312679 URL: https://svnweb.freebsd.org/changeset/base/312679 Log: Handle imx6 erratum ERR004346... to reboot, clear the SRS bit twice within the same cycle of the 32khz clock. I've never actually noticed this error happening, but it's an easy fix. Modified: head/sys/arm/freescale/imx/imx_machdep.c Modified: head/sys/arm/freescale/imx/imx_machdep.c ============================================================================== --- head/sys/arm/freescale/imx/imx_machdep.c Tue Jan 24 01:39:40 2017 (r312678) +++ head/sys/arm/freescale/imx/imx_machdep.c Tue Jan 24 02:09:30 2017 (r312679) @@ -69,11 +69,18 @@ imx_wdog_cpu_reset(vm_offset_t wdcr_phys * Trigger an immediate reset by clearing the SRS bit in the watchdog * control register. The reset happens on the next cycle of the wdog * 32KHz clock, so hang out in a spin loop until the reset takes effect. + * + * Imx6 erratum ERR004346 says the SRS bit has to be cleared twice + * within the same cycle of the 32khz clock to reliably trigger the + * reset. Writing it 3 times in a row ensures at least 2 of the writes + * happen in the same 32k clock cycle. */ if ((pcr = devmap_ptov(wdcr_physaddr, sizeof(*pcr))) == NULL) { printf("cpu_reset() can't find its control register... locking up now."); } else { *pcr &= ~WDOG_CR_SRS; + *pcr &= ~WDOG_CR_SRS; + *pcr &= ~WDOG_CR_SRS; } for (;;) continue;