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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 83BF5C06510 for ; Tue, 2 Jul 2019 17:53:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 62F432082F for ; Tue, 2 Jul 2019 17:53:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="NF9bBrDL"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=cogentembedded-com.20150623.gappssmtp.com header.i=@cogentembedded-com.20150623.gappssmtp.com header.b="AjJ3nxm/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62F432082F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cogentembedded.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:References:To:Subject:From:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yIEMXiEVsENcGevb2EDIRRQK5jWvtFWrYlCA+C1R3AE=; b=NF9bBrDLFeMcqv hdbpLsHK7Rnfi9mGbZT4jBaR4LJjhfUsU7Xi4+nn++JIx8yoMCs3oWPVjZfjOIyjhpbkYMt9k6d9f b1XRbHdTHOkmlXuMtMbOt84xVUYVThNUagRNMXcTjIXHNDsI7fdxgLClj3YUDSZosBP0VxIS3zS1F ojKs0fcKr23Z62twX59SJl0VuqRqR+p/NyFCAn1E3jb0QE5XqzSheWwjVIKirSG631RF+9BS0KQat LYBfjfGk02wTJb2iAVJctoK3F6JTYvueu3smJN+jWXrQv/gnYKkumW7f1EE9v91a+Tr0d2mUA+8FB 9Nw12lMOfVZp190JoJlg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hiMxs-0004uG-Ml; Tue, 02 Jul 2019 17:53:12 +0000 Received: from mail-lj1-x242.google.com ([2a00:1450:4864:20::242]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hiMxl-0004rw-Mg for linux-arm-kernel@lists.infradead.org; Tue, 02 Jul 2019 17:53:07 +0000 Received: by mail-lj1-x242.google.com with SMTP id a21so17821631ljh.7 for ; Tue, 02 Jul 2019 10:53:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cogentembedded-com.20150623.gappssmtp.com; s=20150623; h=from:subject:to:cc:references:organization:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=cMEn3za16fAfd/FKzUgXJWhBF6QU4UvnxjnbeEXsMGQ=; b=AjJ3nxm/0ds+e2hRRivY37RuUEa4V59EPE1atiQr2SXEYP2cvI8PWEN+FZ9oVOntUT XehNOna7XdSk5ef3/jinBVRzP0Zgoq2nXWU3UGYsYB9ehUh1D+3vpTcj0OvQA+seZDU3 JCrKct+QFMpmJzw4R3IcICYfPlRQ1z1j0MHz+N34dj9P+l1gqNZyUktAudZ07GKlOlak joM3F9dzbJiwS1J8pbV/0g+ni/mDtPKuRtxDgvKK6H4TmP8PVNY8odrp5u1fzRFWaBUi Kev+nrvUBH6P4kht+SWadQWqeUZhn9Drib2vk3mjXbi89a1I0olyW75z856NBQ1TpbAj 6QMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:references:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=cMEn3za16fAfd/FKzUgXJWhBF6QU4UvnxjnbeEXsMGQ=; b=S8360TWNGnKIB52D4TAo2vAMbbxMxbzjL5UGPFGr8VDYQD9N32/1C19bsIidH909Lx lg8DDpSN/ZY2PtEXP9lPEZJIUWLcfZfHaAs5sfwLMJ4uKk4frEQCWB6S7hMpCePR2oS4 dooII2l0iu8kK6cYDVoLhYn6IoISr7XFm6SQFWziug7lEi3jmitSTguScut6p37E231U iMd/F6kn6ZVOAAX5nwp3EuZdy6lygifI3TqRmNTPavc4RK7Fjq7limZLPhddCX4QRL6a gD8/CTRG67fv96BHVIS5JIgI6DC1jIpIx8+OFIAITuRBvihblGloQsYziEp44oi6CSW7 OANw== X-Gm-Message-State: APjAAAXdpEn16UdDy89bI0oSXglFWsOzQZa8h7tnOrQhKqLcO/8blSC0 +Goe3fnxg4Ad9n47JBm4TmnbiA== X-Google-Smtp-Source: APXvYqyHA/Ov/gzsKWtHLKt+DUZw1yLzTQf05oQbnhdSu9EIi9OqdKbPqDmV3siOLcwZvcf9+6nKTA== X-Received: by 2002:a2e:93cc:: with SMTP id p12mr18387950ljh.11.1562089983427; Tue, 02 Jul 2019 10:53:03 -0700 (PDT) Received: from wasted.cogentembedded.com ([2a00:1fa0:48c7:f2be:45b6:c800:b809:e0f2]) by smtp.gmail.com with ESMTPSA id g76sm3954000lje.43.2019.07.02.10.53.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Jul 2019 10:53:02 -0700 (PDT) From: Sergei Shtylyov Subject: Re: [PATCH v8 3/5] mtd: Add support for HyperBus memory devices To: Vignesh Raghavendra , Boris Brezillon , Marek Vasut , Richard Weinberger , Rob Herring References: <20190625075746.10439-1-vigneshr@ti.com> <20190625075746.10439-4-vigneshr@ti.com> Organization: Cogent Embedded Message-ID: <31657fd1-c1c9-7672-14c1-e6f67eee6ac1@cogentembedded.com> Date: Tue, 2 Jul 2019 20:53:00 +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: <20190625075746.10439-4-vigneshr@ti.com> Content-Language: en-MW X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190702_105305_883227_1C00D4B8 X-CRM114-Status: GOOD ( 25.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Tokunori Ikegami , linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, Miquel Raynal , Mason Yang , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello! On 06/25/2019 10:57 AM, Vignesh Raghavendra wrote: > Cypress' HyperBus is Low Signal Count, High Performance Double Data Rate > Bus interface between a host system master and one or more slave > interfaces. HyperBus is used to connect microprocessor, microcontroller, > or ASIC devices with random access NOR flash memory (called HyperFlash) > or self refresh DRAM (called HyperRAM). > > Its a 8-bit data bus (DQ[7:0]) with Read-Write Data Strobe (RWDS) > signal and either Single-ended clock(3.0V parts) or Differential clock > (1.8V parts). It uses ChipSelect lines to select b/w multiple slaves. > At bus level, it follows a separate protocol described in HyperBus > specification[1]. > > HyperFlash follows CFI AMD/Fujitsu Extended Command Set (0x0002) similar > to that of existing parallel NORs. Since HyperBus is x8 DDR bus, > its equivalent to x16 parallel NOR flash with respect to bits per clock > cycle. But HyperBus operates at >166MHz frequencies. > HyperRAM provides direct random read/write access to flash memory > array. > > But, HyperBus memory controllers seem to abstract implementation details > and expose a simple MMIO interface to access connected flash. > > Add support for registering HyperFlash devices with MTD framework. MTD > maps framework along with CFI chip support framework are used to support > communicating with flash. > > Framework is modelled along the lines of spi-nor framework. HyperBus > memory controller (HBMC) drivers calls hyperbus_register_device() to > register a single HyperFlash device. HyperFlash core parses MMIO access > information from DT, sets up the map_info struct, probes CFI flash and > registers it with MTD framework. > > Some HBMC masters need calibration/training sequence[3] to be carried > out, in order for DLL inside the controller to lock, by reading a known > string/pattern. This is done by repeatedly reading CFI Query > Identification String. Calibration needs to be done before trying to detect > flash as part of CFI flash probe. > > HyperRAM is not supported at the moment. > > HyperBus specification can be found at[1] > HyperFlash datasheet can be found at[2] > > [1] https://www.cypress.com/file/213356/download > [2] https://www.cypress.com/file/213346/download > [3] http://www.ti.com/lit/ug/spruid7b/spruid7b.pdf > Table 12-5741. HyperFlash Access Sequence > > Signed-off-by: Vignesh Raghavendra [...] I have at least created my HyperBus driver and unfortunately I'm having serious issues with the design of the support core (see below)... [...] > diff --git a/drivers/mtd/hyperbus/hyperbus-core.c b/drivers/mtd/hyperbus/hyperbus-core.c > new file mode 100644 > index 000000000000..63a9e64895bc > --- /dev/null > +++ b/drivers/mtd/hyperbus/hyperbus-core.c > @@ -0,0 +1,154 @@ [...] > +int hyperbus_register_device(struct hyperbus_device *hbdev) > +{ > + const struct hyperbus_ops *ops; > + struct hyperbus_ctlr *ctlr; > + struct device_node *np; > + struct map_info *map; > + struct resource res; > + struct device *dev; > + int ret; > + > + if (!hbdev || !hbdev->np || !hbdev->ctlr || !hbdev->ctlr->dev) { > + pr_err("hyperbus: please fill all the necessary fields!\n"); > + return -EINVAL; > + } > + > + np = hbdev->np; > + ctlr = hbdev->ctlr; > + if (!of_device_is_compatible(np, "cypress,hyperflash")) > + return -ENODEV; > + > + hbdev->memtype = HYPERFLASH; > + > + ret = of_address_to_resource(np, 0, &res); Hm, I doubt that the HB devices are wholly mapped into memory space, that seems like a property of the HB controller. In my case, the flash device in the DT has only single-cell "reg" prop (equal to the chip select #). Then this function returns -EINVAL and the registration fails. Also, in my case such mapping is R/O, not R/W. > + if (ret) > + return ret; > + > + dev = ctlr->dev; > + map = &hbdev->map; > + map->size = resource_size(&res); > + map->virt = devm_ioremap_resource(dev, &res); > + if (IS_ERR(map->virt)) > + return PTR_ERR(map->virt); Again, I doubt that this should be done here, and not in the HB controller driver... [...] MBR, Sergei _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel