From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: [PATCH v1 0/6] misc: add reboot mode driver Date: Tue, 22 Dec 2015 17:47:42 +0100 Message-ID: <20151222164742.GA8623@piout.net> References: <1450774949-23901-1-git-send-email-andy.yan@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1450774949-23901-1-git-send-email-andy.yan-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Andy Yan Cc: robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org, arnd-r2nGTMty4D4@public.gmane.org, john.stultz-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org, catalin.marinas-5wv7dgnIgG8@public.gmane.org, olof-nZhT3qVonbNeoWH0uzbU5w@public.gmane.org, geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, dbaryshkov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, jun.nie-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, joel-U3u1mxZcP9KHXe+LvDLADg@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org, khilman-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, moritz.fischer-+aYTwkv1SeIAvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org List-Id: devicetree@vger.kernel.org Hi, On 22/12/2015 at 17:02:29 +0800, Andy Yan wrote : > > This driver parse the reboot commands like "reboot loader" > and "reboot recovery" to get a boot mode described in the > device tree , then call the vendor specific write interfae > to store the boot mode in some place like special register > or sram , which can be read by the bootloader after system > reboot. > > This is commonly done on Android based devices, in order to > reboot the device into fastboot or recovery mode. > > Before this patch , I have try some hack on[0], and then found > John Stultz also doing the same work[1]. > > As John is busy these days, I go on with this work. > > [0]https://patchwork.kernel.org/patch/7647751/ > [1]https://patchwork.kernel.org/patch/7802391/ > > Changes in v1: > - fix the embarrassed compile warning > - correct the maskrom magic number > - check for the normal reboot > - correct the maskrom magic number > - use macro defined in rockchip_boot-mode.h for reboot-mode DT node > > Andy Yan (6): > dt-bindings: misc: add document for reboot-mode driver > dt-bindings: soc: add document for rockchip reboot-mode driver > misc: add reboot mode driver > soc: rockchip: add reboot mode driver > ARM: dts: rockchip: add reboot-mode node > ARM64: dts: rockchip: add reboot-mode node > This seems nice and useful, some further ideas: > .../devicetree/bindings/misc/reboot-mode.txt | 41 +++++++++ > .../bindings/soc/rockchip/rockchip,reboot-mode.txt | 39 +++++++++ > arch/arm/boot/dts/rk3288.dtsi | 26 ++++++ > arch/arm/boot/dts/rk3xxx.dtsi | 26 ++++++ > arch/arm64/boot/dts/rockchip/rk3368.dtsi | 26 ++++++ > drivers/misc/Kconfig | 7 ++ > drivers/misc/Makefile | 1 + > drivers/misc/reboot_mode.c | 96 ++++++++++++++++++++++ I think this actually belongs to drivers/power/reset/ instead of misc > drivers/soc/rockchip/Kconfig | 9 ++ > drivers/soc/rockchip/Makefile | 1 + > drivers/soc/rockchip/reboot.c | 68 +++++++++++++++ And maybe that part could be made generic instead of rockchip specific. It simply uses a regmap to do the accesses, I guess a lot of other platforms will do that. We have syscon-reboot and syscon-poweroff for example. I think then we can extend the "framework" by having generic drivers to store the value in eeprom or nvram for example. -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html