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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67E66C2D0CD for ; Tue, 17 Dec 2019 19:44:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3BAEA218AC for ; Tue, 17 Dec 2019 19:44:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cogentembedded-com.20150623.gappssmtp.com header.i=@cogentembedded-com.20150623.gappssmtp.com header.b="lMjHeNrD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727909AbfLQToT (ORCPT ); Tue, 17 Dec 2019 14:44:19 -0500 Received: from mail-lj1-f193.google.com ([209.85.208.193]:47043 "EHLO mail-lj1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727849AbfLQToT (ORCPT ); Tue, 17 Dec 2019 14:44:19 -0500 Received: by mail-lj1-f193.google.com with SMTP id z17so12272056ljk.13 for ; Tue, 17 Dec 2019 11:44:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cogentembedded-com.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:references:organization:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Vye4oexJqkfXygyyqfKKuP3+inegaXkNPqfoCHpgpw4=; b=lMjHeNrDcmPquzjFtMxngt+Tg9J0qL9x70PiYWvW1z/pd8s1iFHFz0Vb6ZEYQGn4Gy /1+nYCBnjdA55PBOa7Qo5CZZvxuI5jWXO+vNrhqFSH7p7CcklekDI3G31++vd9nMMHil C+tGHmaL3kFlB5uaTT9GJ9K/AcJL0q2VGWLHBVUjNzk9+R8KI8Vzo07PLFIbK2I4ZK+S ycVfSeVGBr1fFMlqwdStQwEzuzKWEIDjfAsLEZH0Sf6GBPEJ9dmjIjK22vj/60Rn5/y/ WGsHoWuh6WZzBYhL6jzyPa6GC0TIqL4UGBDDtU2rfWPKLi1UBzvHvgzAK8BHA0RJywP7 6VsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=Vye4oexJqkfXygyyqfKKuP3+inegaXkNPqfoCHpgpw4=; b=AUHzDcVrdymA5sqVadMLU64AF4pgBOq5VZRPs8k/Io66TACuiEgX94IXDwRA+oeoTg vIV3G8YiP70XEbfuDi/NuQxfhf8pMTDKrjcwxIQ/XPethCGQKUME3ljScjiHsMV+K6is GP2GTEYQqIBLFVyJBLL7mEGdYNUtmw168tO7Kob1yTuDKd3dsGqhDdpSAEbQS88E3Pn9 PNLO6ecIPVPyGdS/COJD8vna3TZmx0Rax8wM0MddqhsnuqXfwwlhhJzYl1064yWaCYTk jZdRuxNuLoVh9nq1bGXyhrxJbXEIYuziuHek8yvPLncm5YhW9LN8evg33fO/lbFmj7qT xneQ== X-Gm-Message-State: APjAAAUArawCno2t1fQJl7BPJIF6SV3mhaebDzDCQsKde/WUbg28ZnXd RR4xi4CCXp3Q0DpRAAT4ewRaHQ== X-Google-Smtp-Source: APXvYqxGNCXLpZUOsrPpJGhGu15Gp7tw29s3tQRAjYHNkZQ3cn4kdZlrEpaQGbhF+IZ3jDWBkdMdRw== X-Received: by 2002:a2e:920b:: with SMTP id k11mr4291780ljg.111.1576611857779; Tue, 17 Dec 2019 11:44:17 -0800 (PST) Received: from wasted.cogentembedded.com ([2a00:1fa0:411:5312:624c:c19e:baea:21d3]) by smtp.gmail.com with ESMTPSA id m15sm13324733ljg.4.2019.12.17.11.44.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 17 Dec 2019 11:44:16 -0800 (PST) Subject: Re: [PATCH v2 0/6] spi: Add Renesas SPIBSC controller From: Sergei Shtylyov To: Chris Brandt , Mark Brown , Rob Herring , Mark Rutland , Geert Uytterhoeven , Michael Turquette , Stephen Boyd Cc: "linux-spi@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-clk@vger.kernel.org" , Mason Yang , Boris Brezillon References: <20191206134202.18784-1-chris.brandt@renesas.com> <922cfa46-efb5-9e6d-67ea-3ac505b8211c@cogentembedded.com> <590840ce-a250-2512-3d04-c2420d83f7da@cogentembedded.com> Organization: Cogent Embedded Message-ID: <90164352-6b74-ff78-261c-374f51f83330@cogentembedded.com> Date: Tue, 17 Dec 2019 22:44:14 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <590840ce-a250-2512-3d04-c2420d83f7da@cogentembedded.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-MW Content-Transfer-Encoding: 7bit Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 12/16/2019 11:31 PM, Sergei Shtylyov wrote: [...] >> My understanding is that HyperFlash uses standard CFI commands, so all > > The CFI command set driver needed some changes too (e.g. using the status > register to determine if a command is done). > >> we need to do is register a CFI device in the driver, just like we >> register a serial flash device. > >> (I guess I could go look at the sample code for our RTOS package and find out) >> >>>> library that you are proposing have a very different API than just >>>> 'send bytes' and 'receive bytes'? >>> >>> There's "prepare" and "transfer" APIs and also "direct map read" API. > > The 1st one prepares the values to be written in either SPI mode or direct > read mode registers. Then you can call "transfer" or "direct mao read" which > would write out the register values into either set... > >> I wonder what is the value of the "direct map read" (other than XIP in >> RZ/A systems). If you really want to directly access the flash (no >> buffering though the MTD layer), you need to register as a mtd-rom device, >> and then you don't really need an API at all. > > I'd leave this question to Boris, else I never complete this msg. :-) Didn't really summon him, doing that now... :-) >> Chris MBR, Sergei