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 smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DC149C61DC7 for ; Thu, 27 Aug 2026 09:50:29 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 64CA5406E5; Thu, 27 Aug 2026 09:50:29 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id eWQI1DbHh-EG; Thu, 27 Aug 2026 09:50:28 +0000 (UTC) X-Comment: SPF check N/A for local connections - client-ip=140.211.166.142; helo=lists1.osuosl.org; envelope-from=u-boot-bounces@lists.u-boot-project.org; receiver= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lists.u-boot-project.org; s=default; t=1787824228; bh=DMySgr28lJjvuH/0jOFc4c+EURb/gDU1lX1tm3H37Yw=; h=Date:Subject:To:Cc:References:From:In-Reply-To:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=qRNr9Jx+iLFuNOcoOkITtokcD2NYDVYlXEa7jReD2blwcU7kPplMUXDw5zLg0hqbP mqzWb8OiwG4oD1na+zWnXgrMwArGmyqHrq9N835EjIsyQPA2diqFpk+5SLNMwvuCQW 0IXbnll9RkXD/S114M/u/eEdhP/T2l9q/QJ6t7fQgFxpaNDSXS7BI8YKpE2ek5kBcM XkFq99yUSddqOT+5zFJMvd5h54M4hwKXedvrfVqRdLx4vBr0MOAMraV9dgyMc9OaGA AzBMfDkdXV57aEDsJwWuoTUmSzAf6U4zhr/kBYNuw8l3TC4Ye/clsh4VLVE1sh3yb8 PZJZp8TCBYFZw== Received: from lists1.osuosl.org (lists1.osuosl.org [140.211.166.142]) by smtp4.osuosl.org (Postfix) with ESMTP id BE824406B2; Thu, 27 Aug 2026 09:50:28 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists1.osuosl.org (Postfix) with ESMTP id 4CB373A4 for ; Thu, 27 Aug 2026 09:50:28 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 3244080DC6 for ; Thu, 27 Aug 2026 09:50:28 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id r6d2h5_7s3RU for ; Thu, 27 Aug 2026 09:50:27 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2a00:f820:417:0:178:251:229:89; helo=mx.nabladev.com; envelope-from=marex@nabladev.com; receiver= Authentication-Results: smtp1.osuosl.org; dmarc=pass (p=reject dis=none) header.from=nabladev.com Authentication-Results: smtp1.osuosl.org; dkim=pass (2048-bit key, unprotected) header.d=nabladev.com header.i=@nabladev.com header.a=rsa-sha256 header.s=dkim header.b=Km2MwKEl Received: from mx.nabladev.com (mx.nabladev.com [IPv6:2a00:f820:417:0:178:251:229:89]) by smtp1.osuosl.org (Postfix) with ESMTPS id 6BF4E807EF for ; Thu, 27 Aug 2026 09:50:26 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 02B7311C4CB; Thu, 27 Aug 2026 11:50:15 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nabladev.com; s=dkim; t=1787824216; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=DMySgr28lJjvuH/0jOFc4c+EURb/gDU1lX1tm3H37Yw=; b=Km2MwKElrA/XsVcN79qzs1bB312lp1EkZucQmNbLBEaDiNPegxahgl7btVBUL9afKq2zNw KodRb/KHPQ2NuvCF5ZEudKFA7DW1ttDakBu6/Vzxs40PIsSSjgulWnTcGw/DD9EJ22f4jX nSsujY/26UdZZa/h30VfKXLVWdxXTRZk/LGdvNdEvOxgWobOJhRUh7eVmktSJP6EVqIAU5 GzkHggKHb+p0c3iq6AbbPUnbEoW4prSh22+BIoOh7wuGDES11GPAgMCekCtA4+YVJJsT8j 5hLxNWONm7Q0CgjzbAlaB9OOrhOACNRB0836u3QXLFRFPR7kFIe7aXxrmYJOnA== Message-ID: Date: Wed, 26 Aug 2026 14:24:48 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/4] ddr: imx: Allow to call ddr init without logging failure To: Frieder Schrempf , Frieder Schrempf , Stefano Babic , Fabio Estevam , Ilias Apalodimas , Tom Rini , u-boot@lists.u-boot-project.org Cc: uboot-imx@nxp.com, Simona Toaca , Viorel Suman References: <20260819070758.51350-1-frieder@fris.de> <20260819070758.51350-3-frieder@fris.de> <83ee9efb-e09f-45d8-ac0a-cd9b2797c513@nabladev.com> <59ed6576-06dd-42bf-8ea2-18de427955a4@kontron.de> Content-Language: en-US From: Marek Vasut In-Reply-To: <59ed6576-06dd-42bf-8ea2-18de427955a4@kontron.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 X-BeenThere: u-boot@lists.u-boot-project.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.u-boot-project.org On 8/26/26 10:12 AM, Frieder Schrempf wrote: [...] >>> I'm not sure, but even if it would work, it would require several >>> separate init attempts only to read the IDs >> >> Why ? Init the bus in slowest mode with widest bus settings, then try >> MRRD on all available DRAM chips, then figure out which ones report >> valid IDs and which ones fail the MRd . > > As far as I can see this doesn't work. If we use the widest bus setting > (CsPresent=0x3) on a single rank module, the training fails and the DDR > remains in a state where the MR read doesn't work yet. Do you need training to read the IDs ? Simply force-use the slowest bus mode (100 MTps iirc), the training is only relevant for the high-speed modes. [...]