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=-2.2 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 C85BCC47404 for ; Sat, 5 Oct 2019 18:47:03 +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 986F5222C0 for ; Sat, 5 Oct 2019 18:47:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="OWvd6LTd"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="RODcag4X" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 986F5222C0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.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:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=VvejY3SzoD2ZATeiQr+x0IyFtSj5xjEn+JOMffhNkcU=; b=OWvd6LTdmgAr3P Zak5BQBW2B41LhDNxG134GnEo8WLywzGkUSTpkvemMKTUfmGy+cNXLhF8An6gIyV6kDhRY/o6KPxk khL3bof1EO6/FufNM7HHE2LEXL6m1w8shHiBKlT2fm3V/WwfspOqt1PCvcdOYbdv/jUfFj28YdKs0 Dp+WJnEuBdWBtPe0bvJZLtLP7nx9CfWZf+jqfbXRcJ+tPll4fOCEKyhBooSD7ADfb+63YM/XYJozA 4rymQ7lbzwn1AJIJA9G1/Sbs4kuaWC7eHXd+rsY7qY/1AxqFQSrKv6epWGkzG0uijX+H7NZitjn+Z EOH53jM0TpJCSC4eZCUQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iGp50-0000WF-4b; Sat, 05 Oct 2019 18:46:58 +0000 Received: from mail-yb1-xb43.google.com ([2607:f8b0:4864:20::b43]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iGp4x-0000VU-1T for linux-arm-kernel@lists.infradead.org; Sat, 05 Oct 2019 18:46:56 +0000 Received: by mail-yb1-xb43.google.com with SMTP id m1so3283806ybm.1 for ; Sat, 05 Oct 2019 11:46:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=TBJjABokkrKZ/d54kCejrL00qG1tE+E2KRyIwFedZfQ=; b=RODcag4X4gLNgSIcrEODfVVVCxgSvlzgu2+GzOBREj+1fYMTpqnIi3FaI3Gij0vbxO teEzYNgVAMvOT9ghtfx0DVSy0VNyihzmempv+773xWR5LlJvR14sndko+V5lO75yEC5x HN2OS01Wqb1OH5a2mrpqlhapTCz56K3b77FpiYl/x3LoviZNbP1DoSU4QaRQCxjP26BJ Vet5FFTzOliBWSKomDmoCVkOkLVGzZGnrZuFJo53pV5hVs0jnLd/mzWdvOO6N/GOmgfZ jr0BKOowuP5rBZoBuN3Ca+UHTQ9TnF+TCHK5Mb6y8jxTktTVxn1e240U0uOn/ve3yGs9 s53w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=TBJjABokkrKZ/d54kCejrL00qG1tE+E2KRyIwFedZfQ=; b=RmP9HknEbBoB+gJm2lk3a8cGWihzbDGDJWzbiqDM2NCf1bCUkVYrTIuwc4K0Lbjbf/ CWo2mf5fxvr2CyfZXDx086k3Lw7bVgAH8D4v7/gHhjC9Y1AXKDua95nnyIfcg6EAbgz1 LdTG7XC9iwcg+TtqeZbZFqvupbTGSfM1XwlMX588c/aAyprX002SBxjvE4o5bjgMP4F+ 7shZ+ViH+HR89EJow5lsegugFtu5igk0NzBfY4oTkxzEgTJgakSbqDkHf3OQTgMP8Na8 Ge8F3+OiOQvhk37ivolhBUnUiP4P+0hrStqWKcvK+PxrsZeZo0F5sa3WQxwQ++aUjgCl nfDQ== X-Gm-Message-State: APjAAAWBrrbtahwvKfpP/RkEEmku0kf5RvKezZ5671Zvl70wmQwfyjoK 0Ggv854uyvggxAn9W3QjdW4= X-Google-Smtp-Source: APXvYqypjGkV6aP1OrkE5Eb3ln3sgMaerj4stbaQyuaW82pGa7hVgOgDYlnVuxRaYbSmwQJ8cx8w9w== X-Received: by 2002:a25:ab21:: with SMTP id u30mr1521570ybi.143.1570301214234; Sat, 05 Oct 2019 11:46:54 -0700 (PDT) Received: from icarus (072-189-084-142.res.spectrum.com. [72.189.84.142]) by smtp.gmail.com with ESMTPSA id p204sm2597405ywp.110.2019.10.05.11.46.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 05 Oct 2019 11:46:53 -0700 (PDT) Date: Sat, 5 Oct 2019 14:46:40 -0400 From: William Breathitt Gray To: linus.walleij@linaro.org, bgolaszewski@baylibre.com Subject: Re: [PATCH v15 00/14] Introduce the for_each_set_clump8 macro Message-ID: <20191005184640.GA117093@icarus> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191005_114655_148207_667AAC22 X-CRM114-Status: GOOD ( 22.20 ) 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: linux-arch@vger.kernel.org, preid@electromag.com.au, yamada.masahiro@socionext.com, linux-pm@vger.kernel.org, linux@rasmusvillemoes.dk, linux-kernel@vger.kernel.org, morten.tiljeset@prevas.dk, sean.nyekjaer@prevas.dk, linux-gpio@vger.kernel.org, lukas@wunner.de, geert@linux-m68k.org, akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, 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 On Sat, Oct 05, 2019 at 02:36:54PM -0400, William Breathitt Gray wrote: > Changes in v15: > - Move find_next_clump8 to lib/find_bit.c since it requires round_down > (I want this to be static inline like the others, but I need help) > - Utilize for_each_set_clump8 in pisosr, max3191x, and pca953x > > While adding GPIO get_multiple/set_multiple callback support for various > drivers, I noticed a pattern of looping manifesting that would be useful > standardized as a macro. > > This patchset introduces the for_each_set_clump8 macro and utilizes it > in several GPIO drivers. The for_each_set_clump macro8 facilitates a > for-loop syntax that iterates over a memory region entire groups of set > bits at a time. > > For example, suppose you would like to iterate over a 32-bit integer 8 > bits at a time, skipping over 8-bit groups with no set bit, where > XXXXXXXX represents the current 8-bit group: > > Example: 10111110 00000000 11111111 00110011 > First loop: 10111110 00000000 11111111 XXXXXXXX > Second loop: 10111110 00000000 XXXXXXXX 00110011 > Third loop: XXXXXXXX 00000000 11111111 00110011 > > Each iteration of the loop returns the next 8-bit group that has at > least one set bit. > > The for_each_set_clump8 macro has four parameters: > > * start: set to the bit offset of the current clump > * clump: set to the current clump value > * bits: bitmap to search within > * size: bitmap size in number of bits > > In this version of the patchset, the for_each_set_clump macro has been > reimplemented and simplified based on the suggestions provided by Rasmus > Villemoes and Andy Shevchenko in the version 4 submission. > > In particular, the function of the for_each_set_clump macro has been > restricted to handle only 8-bit clumps; the drivers that use the > for_each_set_clump macro only handle 8-bit ports so a generic > for_each_set_clump implementation is not necessary. Thus, a solution for > large clumps (i.e. those larger than the width of a bitmap word) can be > postponed until a driver appears that actually requires such a generic > for_each_set_clump implementation. > > For what it's worth, a semi-generic for_each_set_clump (i.e. for clumps > smaller than the width of a bitmap word) can be implemented by simply > replacing the hardcoded '8' and '0xFF' instances with respective > variables. I have not yet had a need for such an implementation, and > since it falls short of a true generic for_each_set_clump function, I > have decided to forgo such an implementation for now. > > In addition, the bitmap_get_value8 and bitmap_set_value8 functions are > introduced to get and set 8-bit values respectively. Their use is based > on the behavior suggested in the patchset version 4 review. > > William Breathitt Gray (14): > bitops: Introduce the for_each_set_clump8 macro > lib/test_bitmap.c: Add for_each_set_clump8 test cases > gpio: 104-dio-48e: Utilize for_each_set_clump8 macro > gpio: 104-idi-48: Utilize for_each_set_clump8 macro > gpio: gpio-mm: Utilize for_each_set_clump8 macro > gpio: ws16c48: Utilize for_each_set_clump8 macro > gpio: pci-idio-16: Utilize for_each_set_clump8 macro > gpio: pcie-idio-24: Utilize for_each_set_clump8 macro > gpio: uniphier: Utilize for_each_set_clump8 macro > gpio: 74x164: Utilize the for_each_set_clump8 macro > thermal: intel: intel_soc_dts_iosf: Utilize for_each_set_clump8 macro > gpio: pisosr: Utilize the for_each_set_clump8 macro > gpio: max3191x: Utilize the for_each_set_clump8 macro > gpio: pca953x: Utilize the for_each_set_clump8 macro > > drivers/gpio/gpio-104-dio-48e.c | 73 ++++---------- > drivers/gpio/gpio-104-idi-48.c | 36 ++----- > drivers/gpio/gpio-74x164.c | 19 ++-- > drivers/gpio/gpio-gpio-mm.c | 73 ++++---------- > drivers/gpio/gpio-max3191x.c | 19 ++-- > drivers/gpio/gpio-pca953x.c | 17 ++-- > drivers/gpio/gpio-pci-idio-16.c | 75 +++++--------- > drivers/gpio/gpio-pcie-idio-24.c | 109 ++++++++------------- > drivers/gpio/gpio-pisosr.c | 12 +-- > drivers/gpio/gpio-uniphier.c | 16 ++- > drivers/gpio/gpio-ws16c48.c | 73 ++++---------- > drivers/thermal/intel/intel_soc_dts_iosf.c | 29 +++--- > drivers/thermal/intel/intel_soc_dts_iosf.h | 2 - > include/asm-generic/bitops/find.h | 50 ++++++++++ > include/linux/bitops.h | 5 + > lib/find_bit.c | 14 +++ > lib/test_bitmap.c | 65 ++++++++++++ > 17 files changed, 325 insertions(+), 362 deletions(-) > > -- > 2.23.0 This patchset only implements for_each_set_clump8 which restricts the looping to 8 bits at a time. The drivers/gpio/gpio-thunderx.c file has a set_multiple callback that loops 64 bits at a time. That would be one case where a more general for_each_set_clump macro would be useful. However, we can focus on the simpler for_each_set_clump8 macro for now since looping by 8 bits at a time is the most common situation. William Breathitt Gray _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel