Received: by 2002:ac0:a582:0:0:0:0:0 with SMTP id m2-v6csp797218imm; Thu, 4 Oct 2018 03:35:56 -0700 (PDT) X-Google-Smtp-Source: ACcGV60sg27b24H5j8ytZLuKuiQ9IbqvN0qriyv7qYW+JUG71rpezdPmDsk73ZOxeCDbh4I71Uxd X-Received: by 2002:a62:104b:: with SMTP id y72-v6mr6129322pfi.113.1538649356695; Thu, 04 Oct 2018 03:35:56 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1538649356; cv=none; d=google.com; s=arc-20160816; b=EYet9N3RoJrQYb+rM3vPqYtFHeRyuuIL+azvIVCJnr+8ii/Sn+P33oacjk6j54kV5W R94mRuNyIMRHVwzAwaGRwZ9OZ4XmdagRYxCmYcHflN2WawkzOGwzrswaC3uErauJKXlL iEEKfmnC2iI/dncRgipFTmY+OWejNB7S7Ynn1ReUiTotJtwlm2wO+77t9uIoOS8Jny+v xixnUDF4mAKCMzdmXnrqp6zvVSUiQhVyd/EcncYFY9H+ydu2Czx6cJBZmFVvh5gB30Dh oos8FadTFesCv1iIbjwTgwShtkKMKFdxbn4MgyL/vFq3s53sR2lv0gVvP0270Eo/FOcs lduQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:references:cc:to:subject:dkim-signature; bh=hu+xnYYzGk2P9gNOGFoNFjwX9zxr3COvS1l5ek5/jzc=; b=SWSVSkFV2kP9qzEAPVCqWj0kp0ovT9HOxNMw5jdHhlGKcHeL1Q4nHYs5rKwLokhwN0 zwx1PF0jw3uxQd5RrhqMuFAFtkZsCDeQSTCKtaJ7OoDdmlrUch4KseYbGaYw8k8iseD3 CagiFQthBBZOwgPsa7aSmTH1JtVI4WvidBLnr7rSp1G4Rd7v7zw1KDQJUmFccnrq/Bml AkbqfteXwvBxwx0MLATKfbhKcCb8oeP5fopL/if0TOSapNcYAJdgKisDtg6x9pwH8t/R tl1YKPJP6XEXQHpg+C5l4hK/d8C9ALGvKKB8sIJxIRSSk/PZDAM3H5OvFZseNnzEldQw xsVQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@ti.com header.s=ti-com-17Q1 header.b=Lz6quGne; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=ti.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id w4-v6si4928305pfb.52.2018.10.04.03.35.40; Thu, 04 Oct 2018 03:35:56 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@ti.com header.s=ti-com-17Q1 header.b=Lz6quGne; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=ti.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727394AbeJDR1r (ORCPT + 99 others); Thu, 4 Oct 2018 13:27:47 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:57986 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727203AbeJDR1r (ORCPT ); Thu, 4 Oct 2018 13:27:47 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id w94AYjKU095336; Thu, 4 Oct 2018 05:34:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1538649285; bh=hu+xnYYzGk2P9gNOGFoNFjwX9zxr3COvS1l5ek5/jzc=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=Lz6quGnepJa91jMLgfrvsYYos5uFBiE7o+KZ7rRaMmyrCktc2G2TLDAjVptSjV5Nw 4SCykDwq2amG0gVLhE4vCFLDMytPvSsJD3fplbGF4Q4O3Q7QNtAYpBA+vgqFqlJAz8 n1VSbO67wKrdQcYmYaCCTn1LsrSmN5Ej01/heBks= Received: from DLEE113.ent.ti.com (dlee113.ent.ti.com [157.170.170.24]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id w94AYjBR027789; Thu, 4 Oct 2018 05:34:45 -0500 Received: from DLEE100.ent.ti.com (157.170.170.30) by DLEE113.ent.ti.com (157.170.170.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1466.3; Thu, 4 Oct 2018 05:34:45 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1466.3 via Frontend Transport; Thu, 4 Oct 2018 05:34:45 -0500 Received: from [172.24.190.89] (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id w94AYfwY028400; Thu, 4 Oct 2018 05:34:42 -0500 Subject: Re: [PATCH 0/3] spi-nor: Add Octal SPI support To: Boris Brezillon CC: Marek Vasut , Rob Herring , , Yogesh Gaur , , , Brian Norris , Linux ARM Mailing List , Tudor Ambarus References: <20181003165603.2579-1-vigneshr@ti.com> <20181003212017.653e739f@bbrezillon> From: Vignesh R Message-ID: <1074d503-71ef-2998-7096-de6135bb965d@ti.com> Date: Thu, 4 Oct 2018 16:05:36 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181003212017.653e739f@bbrezillon> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 04 October 2018 12:50 AM, Boris Brezillon wrote: > On Wed, 3 Oct 2018 22:26:00 +0530 > Vignesh R wrote: > >> This series adds support for octal mode of mt35x flash. Also, adds >> support for OSPI version of Cadence QSPI controller. >> >> Based on top of patches adding basic support for mt35xu512aba here: >> https://patchwork.ozlabs.org/cover/971437/ >> >> Vignesh R (3): >> mtd: spi-nor: Add Octal mode support for mt35xu512aba >> dt-bindings: cadence-quadspi: Add new compatible for AM654 SoC >> mtd: spi-nor: cadence-quadspi: Add support for Octal SPI controller > > The patchset looks good to me, I'll just wait the next release cycle > before applying it, since I'd prefer to have it stay a bit longer in > -next. This should leave enough time to let other people review this > stuff. > Ok, thats fine... >> >> .../devicetree/bindings/mtd/cadence-quadspi.txt | 1 + >> drivers/mtd/spi-nor/cadence-quadspi.c | 9 +++++++++ > > On a slightly different topic, do you plan to convert the Cadence > driver to spi-mem? And if you don't, is it because you don't have time > or because some features are missing in spi-mem (I remember you > mentioned a few things back when you were reviewing the spi-mem series)? > I do not have plans to convert cadence QSPI driver to spi-mem yet, mainly due to lack of time. Also, not sure if original author Marek and other altera people are okay with that. I see couple of issues in the way of conversion: 1. I would wait to know what direction would direct mapping APIs[1] go before starting spi-mem conversion for Cadence QSPI driver. Else, we have may to re write again if direct mapping APIs are merged. 2. New Cadence OSPI IP has an integrated PHY to support high throughput OSPI flashes operating up 200MHz in Octal DDR mode. In order to work with such flashes, PHY DLLs need to be calibrated. Highly simplified calibration sequence is as below(See [2] for actual sequence): -Read flash ID at low speed and store it. -Enable PHY and set DLLs to a defined initial value -Increment RX DLL value -Read flash ID and check for correctness of data read -repeat above two steps until a band of passing values is obtained for RX DLL where flash ID is correctly read. -DLL needs to set to middle of the passing band. I am trying to figure out how to fit this into the spi-mem framework as controller would to need to store READ ID opcode and expected JEDEC ID before starting calibration sequence. [1]https://patchwork.ozlabs.org/cover/924041/ [2]http://www.ti.com/lit/ug/spruid7a/spruid7a.pdf(12.3.2.4.14 PHY Module page 9770-9772) -- Regards Vignesh