From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Tue, 09 Aug 2022 11:55:42 +0200 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oLLxc-00HEk6-5m for lore@lore.pengutronix.de; Tue, 09 Aug 2022 11:55:42 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oLLxc-0000nQ-E8 for lore@pengutronix.de; Tue, 09 Aug 2022 11:55:41 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pHo3ndwt6bNwM5sM6+f0pyJSfU0bhzdRfPa4xMZEaRA=; b=HmDRxtllt4t7Od3+9Bevxra6MD 6sNfNuf9b0IOmeEO4nbFBB2OjjXETpa++NNhwcolQqdpDdlZq88cNnPiosM1SEzS/kS+wDM/OZ21P QACJUsodjUZVDwmpV9xzvV9DNxopbrhTbWp5FJDUWYKcceRqViACUkuebcWBDaRFkdEg92PSptUXj nst3ckFCjc6bIaNcNNxdwkU+VbinYoA+c88A2iwTMo0SFhwAMvHFE9YrOYLvXXhZmgaGOARHj51/t SRjC5yB2I5P1mSmQQIyT/F9J5MSP8naHEVKELp2poxsU6HZ78J1EaBUoj/mI40Owu9uRUIZHguooh xCyP/JdQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oLLwL-0039ID-Eh; Tue, 09 Aug 2022 09:54:21 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oLLwF-0039H0-Rb for barebox@lists.infradead.org; Tue, 09 Aug 2022 09:54:17 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1oLLwE-0000Ug-5q; Tue, 09 Aug 2022 11:54:14 +0200 Message-ID: <82e482ad-7c4e-edd1-49d1-4c16ee4fbb3a@pengutronix.de> Date: Tue, 9 Aug 2022 11:54:13 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Content-Language: en-US To: Sascha Hauer Cc: barebox@lists.infradead.org References: <20220809062938.1750369-1-a.fatoum@pengutronix.de> <20220809062938.1750369-4-a.fatoum@pengutronix.de> <20220809094902.GP31528@pengutronix.de> From: Ahmad Fatoum In-Reply-To: <20220809094902.GP31528@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220809_025415_936904_C320CA92 X-CRM114-Status: GOOD ( 23.74 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-4.0 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 4/4] ARM: dts: stm32mp: add bootrom serial (DFU) reboot mode X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) Hello Sascha, On 09.08.22 11:49, Sascha Hauer wrote: > On Tue, Aug 09, 2022 at 08:29:38AM +0200, Ahmad Fatoum wrote: >> The same register we use for the reboot mode communication between Linux >> and barebox is also sampled by the bootrom. If the lowest 16 bits of it >> are 0x00FF, the bootrom will enter DFU mode. Add the appropriate >> reboot-mode, but with a barebox, prefix, so Linux doesn't automatically >> provide it to userspace along with the existing loader and recovery >> modes. > > Why do we need to prevent Linux from providing dfu mode to userspace? > Isn't that a vlid usecase? It is, but I don't want a barebox update to add this feature by default. So, communication with BootROM = not exported by default Communication with Linux = exported by default and this can be overridden on a per-board basis via device tree. We do this likewise for the i.MX6 and i.MX8 where we have barebox,syscon-reboot-mode which isn't processed by Linux, but we can't use this here because the same register is used for both modes of communication. Cheers, Ahmad > > Sascha > >> >> Signed-off-by: Ahmad Fatoum >> --- >> arch/arm/dts/stm32mp151.dtsi | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm/dts/stm32mp151.dtsi b/arch/arm/dts/stm32mp151.dtsi >> index ed7cf6192bea..ac6536a556a9 100644 >> --- a/arch/arm/dts/stm32mp151.dtsi >> +++ b/arch/arm/dts/stm32mp151.dtsi >> @@ -41,9 +41,10 @@ >> reboot_mode_tamp: reboot-mode { >> compatible = "syscon-reboot-mode"; >> offset = <0x150>; /* reg20 */ >> - mask = <0xff>; >> + mask = <0xffff>; >> mode-normal = <0>; >> mode-loader = <0xBB>; >> mode-recovery = <0xBC>; >> + barebox,mode-serial = <0xFF>; >> }; >> }; >> -- >> 2.30.2 >> >> >> > -- 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 |