From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Yan Subject: Re: [PATCH v5 1/4] dt-bindings: power: reset: add document for reboot-mode driver Date: Fri, 18 Mar 2016 16:43:29 +0800 Message-ID: <56EBBFB1.6000808@rock-chips.com> References: <1457439716-8084-1-git-send-email-andy.yan@rock-chips.com> <1457439785-8133-1-git-send-email-andy.yan@rock-chips.com> <20160317155212.GA19171@rob-hp-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20160317155212.GA19171@rob-hp-laptop> Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring Cc: john.stultz@linaro.org, arnd@arndb.de, heiko@sntech.de, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, olof@lixom.net, alexandre.belloni@free-electrons.com, dbaryshkov@gmail.com, sre@kernel.org, jun.nie@linaro.org, edubezval@gmail.com, f.fainelli@gmail.com, will.deacon@arm.com, linux-rockchip@lists.infradead.org, wxt@rock-chips.com, matthias.bgg@gmail.com, linux@arm.linux.org.uk, lorenzo.pieralisi@arm.com, moritz.fischer@ettus.com, richard@nod.at, dwmw2@infradead.org, jwerner@google.com List-Id: linux-rockchip.vger.kernel.org Hi Rob: On 2016=E5=B9=B403=E6=9C=8817=E6=97=A5 23:52, Rob Herring wrote: > On Tue, Mar 08, 2016 at 08:23:05PM +0800, Andy Yan wrote: >> add device tree bindings document for reboot-mode driver >> >> Signed-off-by: Andy Yan >> >> --- >> >> Changes in v5: >> - delete a unnecessary blank line in syscon-reboot-mode.txt >> - rename macro BOOT_LOADER to BOOT_BL_DOWNLOAD, which gives a more c= lear mean >> >> Changes in v4: >> - remove mode-maskrom >> - rename mode-fastboot to mode-bootloader to keep compatible with th= e exiting Android device >> >> Changes in v3: >> - descirbe all reboot mode as properity instead of subnode >> >> Changes in v2: None >> Changes in v1: None >> >> .../bindings/power/reset/reboot-mode.txt | 24 ++++++++++= +++++ >> .../bindings/power/reset/syscon-reboot-mode.txt | 34 ++++++++++= ++++++++++++ >> 2 files changed, 58 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/power/reset/r= eboot-mode.txt >> create mode 100644 Documentation/devicetree/bindings/power/reset/s= yscon-reboot-mode.txt >> >> diff --git a/Documentation/devicetree/bindings/power/reset/reboot-mo= de.txt b/Documentation/devicetree/bindings/power/reset/reboot-mode.txt >> new file mode 100644 >> index 0000000..3457949 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/power/reset/reboot-mode.txt >> @@ -0,0 +1,24 @@ >> +Generic reboot mode core map driver >> + >> +This driver get reboot mode arguments and call the write >> +interface to stores the magic value in special register >> +or ram . Then the bootloader can read it and take different >> +action according the argument stored. >> + >> +All mode properties are vendor specific, it is a indication to tell >> +the bootloder what to do when the system reboot, and should be name= d >> +as mode-xxx =3D (xxx is mode name). >> + >> +- mode-normal: Normal reboot mode, system reboot with command "rebo= ot". >> +- mode-recovery: Android Recovery mode, it is a mode to format the = device or update a new image. >> +- mode-bootloader: Android fastboot mode, it's a mode to re-flash p= artitions on the Android based device. >> +- mode-loader: A bootloader mode, it's a mode used to download imag= e on Rockchip platform, >> + usually used in development. >> + >> +Example: >> + reboot-mode { >> + mode-normal =3D ; >> + mode-recovery =3D ; >> + mode-bootloader =3D ; >> + mode-loader =3D ; >> + } >> diff --git a/Documentation/devicetree/bindings/power/reset/syscon-re= boot-mode.txt b/Documentation/devicetree/bindings/power/reset/syscon-re= boot-mode.txt >> new file mode 100644 >> index 0000000..d03cb52 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/power/reset/syscon-reboot-mo= de.txt >> @@ -0,0 +1,34 @@ >> +SYSCON reboot mode driver >> + >> +This driver get reboot mode magic value form reboot-mode driver >> +and stores it in a SYSCON mapped register. Then the bootloader >> +can read it and take different action according to the magic >> +value stored. >> + >> +This DT node should be represented as a sub-node of a "syscon", "si= mple-mfd" >> +node. >> + >> +Required properties: >> +- compatible: should be "syscon-reboot-mode" >> +- offset: offset in the register map for the storage register (in b= ytes) >> + >> +Optional properity: >> +- mask: the mask bits of the mode magic value, default set to 0xfff= fffff if missing. > I can't see how this is used. I would drop it for now. > > With that change: > > Acked-by: Rob Herring The mask is suggested by Moritz Fischer in V2[0]. And I found Tegra did= =20 indeed only use some bits of one register to store the reboot mode[1]. @Heiko: It seems that this patch series can land now, but the dts parts= =20 belong to two different branch(arm32 and arm64) . And these two parts both depends on one head file rockchip_boot-mode.h, So I hope= =20 some suggestions from you how to deal with it. [0] https://lkml.org/lkml/2016/1/27/225 [1] drivers/soc/tegra/pmc.c (tegra_pmc_restart_notify) >> + >> +The rest of the properties should follow the generic reboot-mode di= scription >> +found in reboot-mode.txt >> + >> +Example: >> + pmu: pmu@20004000 { >> + compatible =3D "rockchip,rk3066-pmu", "syscon", "simple-mfd"; >> + reg =3D <0x20004000 0x100>; >> + >> + reboot-mode { >> + compatible =3D "syscon-reboot-mode"; >> + offset =3D <0x40>; >> + mode-normal =3D ; >> + mode-recovery =3D ; >> + mode-bootloader =3D ; >> + mode-loader =3D ; >> + }; >> + }; >> --=20 >> 1.9.1 >> >> >> > >