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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 98230C43381 for ; Mon, 25 Feb 2019 10:49:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D66C2147C for ; Mon, 25 Feb 2019 10:49:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726743AbfBYKtU (ORCPT ); Mon, 25 Feb 2019 05:49:20 -0500 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:29348 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726574AbfBYKtT (ORCPT ); Mon, 25 Feb 2019 05:49:19 -0500 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1PAkgUo024029; Mon, 25 Feb 2019 11:48:59 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-00178001.pphosted.com with ESMTP id 2qtv6chp8w-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 25 Feb 2019 11:48:59 +0100 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 5C9FD3F; Mon, 25 Feb 2019 10:48:58 +0000 (GMT) Received: from Webmail-eu.st.com (sfhdag6node1.st.com [10.75.127.16]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 1BE202867; Mon, 25 Feb 2019 10:48:58 +0000 (GMT) Received: from [10.48.0.237] (10.75.127.49) by SFHDAG6NODE1.st.com (10.75.127.16) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 25 Feb 2019 11:48:57 +0100 Subject: Re: [PATCH 0/2] mmc: mmci: add quirk property to add stm32 transfer mode To: Russell King - ARM Linux admin CC: , Ulf Hansson , Alexandre Torgue , , , Rob Herring , , Maxime Coquelin , , References: <1550743851-13588-1-git-send-email-ludovic.Barre@st.com> <20190221102739.cc37au6elqu6gvfe@shell.armlinux.org.uk> <20190221103049.tspc5igoe6wmt3jd@shell.armlinux.org.uk> <20190221140300.y3tunrvsh3gyig5f@shell.armlinux.org.uk> From: Ludovic BARRE Message-ID: <9c88d76c-2080-71b1-c9c6-c24d0f0aeb91@st.com> Date: Mon, 25 Feb 2019 11:48:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190221140300.y3tunrvsh3gyig5f@shell.armlinux.org.uk> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.49] X-ClientProxiedBy: SFHDAG7NODE2.st.com (10.75.127.20) To SFHDAG6NODE1.st.com (10.75.127.16) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-25_06:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi Russell & Ulf On 2/21/19 3:03 PM, Russell King - ARM Linux admin wrote: > On Thu, Feb 21, 2019 at 02:38:36PM +0100, Ludovic BARRE wrote: >> hi Russell & Ulf >> >> On 2/21/19 11:30 AM, Russell King - ARM Linux admin wrote: >>> On Thu, Feb 21, 2019 at 10:27:39AM +0000, Russell King - ARM Linux admin wrote: >>>> On Thu, Feb 21, 2019 at 11:10:49AM +0100, Ludovic Barre wrote: >>>>> From: Ludovic Barre >>>>> >>>>> This patch series introduces a bitmap of hardware quirks that require >>>>> some special action. This should reduce the number of boolean >>>>> into variant structure. >>>>> And adds quirk bit to define sdmmc specific transfer modes. >>>> >>>> Please find some other way to deal with these differences. As far as >>>> I'm concerned, introducing a quirk bitmask such as what was done in >>>> sdhci is a complete disaster and leads to long-term maintanability >>>> problems. >>>> >>>> We already have a way to deal with variants in mmci. >>> >>> ... to finish what I was saying ... >>> >>> and I think that: >>> >>> if (variant->blksz_datactrl16) >>> datactrl = variant->datactrl_dpsm_enable | (data->blksz << 16); >>> else if (variant->blksz_datactrl4) >>> datactrl = variant->datactrl_dpsm_enable | (data->blksz << 4); >>> else >>> datactrl = variant->datactrl_dpsm_enable | blksz_bits << 4; >>> >>> ought to become a variant function call which returns the appropriate >>> datactrl value. This would shrink the amount of variant testing in this >>> path, and also means that going forward we aren't facing an endlessly >>> increasing number of tests here. >> >> For blksz_datactrl case: >> We could create an inline function for datactrl16 and blksz_datactrl4 >> which returns the appropriate datactrl value (specific for ux500v2 and >> qcom). This function could be register in mmci_host_ops structure. > > Yes, this is what I'm proposing (except for the "inline" bit which > seems meaningless if it's called via the mmci_host_ops structure.) > I'm also proposing that it shouldn't just be the blksz that's > returned but anything that the variant needs to take account of, > including the stm transfer mode. Ulf, are you alright with this callback approach (just to be sure that every body is align, before send a patch)? This mmci_host_ops callback could return datactrl config to start data (defined by variant). > >> in mmci_start_data function we could call a common function which call a >> hook if defined. >> >> int mmci_dblksz(struct mmci_host *host) > > As this is returning a register value, "u32" would be more appropriate > than "int". > >> { >> if (host->ops && host->ops->dblksz) >> return host->ops->dblk(host); >> >> /* default data block size definition */ >> blksz_bits = ffs(data->blksz) - 1; >> return blksz_bits << 4; >> } >> >> what do you think about it? > > I don't see any reason not to make the call unconditional and have every > variant supply an appropriate function pointer. IMHO that keeps stuff > cleaner. > >> After, I'm afraid to multiply callback function in mmci_host_ops. >> >> For stm32 transfer mode: >> ditto, a callback function or I keep a boolean? >> >> BR >> Ludo >> >>> >>>> >>>>> >>>>> Ludovic Barre (2): >>>>> mmc: mmci: introduce a quirks property into variant struct >>>>> mmc: mmci: add quirk property to add stm32 transfer mode >>>>> >>>>> drivers/mmc/host/mmci.c | 11 +++++++++++ >>>>> drivers/mmc/host/mmci.h | 9 +++++++++ >>>>> 2 files changed, 20 insertions(+) >>>>> >>>>> -- >>>>> 2.7.4 >>>>> >>>>> >>>>> _______________________________________________ >>>>> linux-arm-kernel mailing list >>>>> linux-arm-kernel@lists.infradead.org >>>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >>>>> >>>> >>>> -- >>>> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ >>>> FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up >>>> According to speedtest.net: 11.9Mbps down 500kbps up >>>> >>>> _______________________________________________ >>>> linux-arm-kernel mailing list >>>> linux-arm-kernel@lists.infradead.org >>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >>>> >>> >> >