From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EC7CCCF2D3 for ; Mon, 19 Oct 2026 07:36:14 +0000 (UTC) Received: from ocn-dfr-mts-118c1.ocn.ad.jp (ocn-dfr-mts-118c1.ocn.ad.jp [153.128.190.140]) by mx.groups.io with SMTP id smtpd.msgproc02-g2.1258.1792213636286881297 for ; Fri, 16 Oct 2026 22:07:16 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@docomonet.jp header.s=20240125 header.b=jpWJhOxq; spf=pass (domain: docomonet.jp, ip: 153.128.190.140, mailfrom: y-asai.0816@docomonet.jp) Received: from ocn-ckd-mts-121c38.ocn.ad.jp (ocn-ckd-mts-121c38.ocn.ad.jp [180.55.181.103]) by ocn-dfr-mts-118c1.ocn.ad.jp (Postfix) with ESMTP id B96FB190 for ; Sat, 17 Oct 2026 14:01:57 +0900 (JST) Received: from ocn-spm-mts-103c1.ocn.ad.jp (ocn-spm-mts-103c1.ocn.ad.jp [153.128.190.230]) by ocn-ckd-mts-121c38.ocn.ad.jp (Postfix) with ESMTP id 164A61C0007C8; Sat, 17 Oct 2026 14:01:54 +0900 (JST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=docomonet.jp; s=20240125; t=1792213314; bh=8FY8OPrcbKHszmn2Bylyp47ZbL+PHHVuIpFuYCdET0s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jpWJhOxqw8kWCVZOsr9U5imuTD1yryGrAyiXcF2eJjgO/ts0IrlQ8Ga0EqTa9nwH8 tR7ImoI/gdH6qQdjNkfT2/BHxijypMV1bQr6sJvmucUFUECNfvPWDoRYxIbTARYpPj n+6uMlMu/LPwiPry8CoEB45WQUjKYrRNk5bYP6OQ= Received: from ocn-vc-mts-112c1.ocn.ad.jp ([153.149.236.166]) by ocn-spm-mts-103c1 with ngmta id a753f171-18df388376ffdffb; Sat, 17 Oct 2026 14:01:54 +0900 Received: from ocn-sdpx-mts-111c1.ocn.ad.jp ([153.128.117.205]) by ocn-vc-mts-112c1 with ngmta id aabe4ed6-18df38832f430fa2; Sat, 17 Oct 2026 14:01:53 +0900 Received: from docomonet.jp (p3688129-ipoe.ipoe.ocn.ne.jp [153.238.101.128]) by ocn-sdpx-mts-111c1.ocn.ad.jp (Postfix) with ESMTPA; Sat, 17 Oct 2026 14:01:52 +0900 (JST) From: "Asai, Shigeaki" To: Quentin Schulz , u-boot@lists.u-boot-project.org Cc: u-boot-amlogic@groups.io, neil.armstrong@linaro.org, jh80.chung@samsung.com, peng.fan@nxp.com, kever.yang@rock-chips.com, sjg@chromium.org, trini@konsulko.com, ilias.apalodimas@linaro.org Subject: Re: [PATCH 2/2] arm: dts: meson-g12b-odroid-go-ultra-u-boot: set vddio_c to 3.3V Date: Sat, 17 Oct 2026 14:01:52 +0900 MIME-Version: 1.0 X-Mailer: HidemaruMail 7.42 (WinNT,A00) In-Reply-To: <69377c9e-b4a1-462a-b82d-66e13b465626@0leil.net> References: <20261010013237.2269021-1-y-asai.0816@docomonet.jp> <20261010013237.2269021-3-y-asai.0816@docomonet.jp> <69377c9e-b4a1-462a-b82d-66e13b465626@0leil.net> Message-Id: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Id: X-Webhook-Received: from 45-33-107-173.ip.linodeusercontent.com [45.33.107.173] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Mon, 19 Oct 2026 07:36:14 -0000 X-Groupsio-URL: https://groups.io/g/u-boot-amlogic/message/3136 Hi Quentin, Thank you for the review. On 10/16/26, Quentin Schulz wrote: > I'll let Neil decide since he's the maintainer of that code, but I don't > think this is necessarily correct? The spec specifically allows > 2.7-3.6V, c.f. https://www.sdcard.org/developers/sd-standard-overview/. > > Moreover, RK3399 Puma has 1.8-3.0V only, and it's been working fine for > years now (though I haven't checked with that SD card specifically). > > What happens if you do NOT use the SD in U-Boot at all and boot straight > to the Linux kernel, is it also broken in the Linux kernel then? If not, > then your issue is probably not what your tool output and we may have an > issue elsewhere (possibly in the MMC subsystem for example). Linux is fine with this card at 3.0V. Linux itself sets vddio_c to 3.0V, and the system runs from the same card (SD high speed, 50MHz) with no errors in dmesg. Following your comments, I tested again without this patch, and I can no longer reproduce the problem. I tried U-Boot 2025.07, 2026.07 and 2026.10, with and without patch 1/2, and three SD cards, including the one in the commit message. In about 35 reboots from Linux, U-Boot always read the card and booted the kernel. At the U-Boot prompt after a reboot, vddio_c was 3.0V and the SD card ran at 40MHz, so the conditions were the same as in my original report. I do not know what was different when I saw the failure. So I agree that 3.0V is probably not the cause, and I will drop this patch. If I can reproduce the problem again, I will look at it again, including the MMC side as you suggested. Neil, sorry for the noise. Best regards, Shigeaki Asai (This reply was written with the help of Claude.)