From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:33266 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752906AbdHOCSt (ORCPT ); Mon, 14 Aug 2017 22:18:49 -0400 Date: Mon, 14 Aug 2017 19:18:47 -0700 From: Guenter Roeck To: Christopher Bostic Cc: wim@iguana.be, robh+dt@kernel.org, mark.rutland@arm.com, joel@jms.id.au, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, openbmc@lists.ozlabs.org Subject: Re: [v5, 1/2] drivers/watchdog: Add optional ASPEED device tree properties Message-ID: <20170815021847.GB1819@roeck-us.net> References: <20170717192539.7950-2-cbostic@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170717192539.7950-2-cbostic@linux.vnet.ibm.com> Sender: linux-watchdog-owner@vger.kernel.org List-Id: linux-watchdog@vger.kernel.org On Mon, Jul 17, 2017 at 02:25:38PM -0500, Christopher Bostic wrote: > Describe device tree optional properties: > > * aspeed,reset-type = "cpu|soc|system|none" > One of three different, mutually exclusive, values > > "cpu" : ARM CPU reset on signal > "soc" : 'System on chip' reset > "system" : Full system reset > > The value can also be set to "none" which indicates that no > reset of any kind is to be done via this watchdog. This assumes > another watchdog on the chip is to take care of resets. > > * aspeed,external-signal - Generate external signal (WDT1 and WDT2 only) > * aspeed,alt-boot - Boot from alternate block on signal > > Signed-off-by: Christopher Bostic > Acked-by: Rob Herring Reviewed-by: Guenter Roeck > --- > v5 - Removed aspeed,interrupt property - no plans at this point to > need this functionality in the driver. > v4 - Add aspeed-reset-type and assign one of four values, > cpu, soc, system, none. > v3 - Invert soc and sys reset to 'no' to preserve backwards > compatibility. SOC and SYS reset will be set by default > without any optional parameters set > v2 - Add 'aspeed,' prefix to all optional properties > - Add arm-reset, soc-reset, interrupt, alt-boot properties > --- > .../devicetree/bindings/watchdog/aspeed-wdt.txt | 32 ++++++++++++++++++++++ > 1 file changed, 32 insertions(+) > > diff --git a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt > index c5e74d7..2b34ce9 100644 > --- a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt > +++ b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt > @@ -8,9 +8,41 @@ Required properties: > - reg: physical base address of the controller and length of memory mapped > region > > +Optional properties: > + > + - aspeed,reset-type = "cpu|soc|system|none" > + > + Reset behavior - Whenever a timeout occurs the watchdog can be programmed > + to generate one of three different, mutually exclusive, types of resets. > + > + Type "none" can be specified to indicate that no resets are to be done. > + This is useful in situations where another watchdog engine on chip is > + to perform the reset. > + > + If 'aspeed,reset-type=' is not specfied the default is to enable system > + reset. > + > + Reset types: > + > + - cpu: Reset CPU on watchdog timeout > + > + - soc: Reset 'System on Chip' on watchdog timeout > + > + - system: Reset system on watchdog timeout > + > + - none: No reset is performed on timeout. Assumes another watchdog > + engine is responsible for this. > + > + - aspeed,external-signal: If property is present then signal is sent to > + external reset counter (only WDT1 and WDT2). If not > + specified no external signal is sent. > + - aspeed,alt-boot: If property is present then boot from alternate block. > + > Example: > > wdt1: watchdog@1e785000 { > compatible = "aspeed,ast2400-wdt"; > reg = <0x1e785000 0x1c>; > + aspeed,reset-type = "system"; > + aspeed,external-signal; > };