From patchwork Sat Apr 25 18:59:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Syed Nayyar Waris X-Patchwork-Id: 11510023 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AF3F71805 for ; Sat, 25 Apr 2020 19:00:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 889CD2074F for ; Sat, 25 Apr 2020 19:00:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="lD9oBsew" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726197AbgDYTAK (ORCPT ); Sat, 25 Apr 2020 15:00:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726182AbgDYTAK (ORCPT ); Sat, 25 Apr 2020 15:00:10 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E71CC09B04D; Sat, 25 Apr 2020 12:00:10 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id e6so5332097pjt.4; Sat, 25 Apr 2020 12:00:10 -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:mime-version:content-disposition :user-agent; bh=mHbZ4xPUa2e8Z9ySz/Reqmt5mff2C3fDEKHsxtsl+2U=; b=lD9oBsew9gmagpFSaBbrod7+Dg6O9/fj1ury4cFPHeDkSTIIemQazMeG1h6gxz5EEr 2y0ubQjNt36fCEMrU7x/WFUDCndf+PIC5Igp9MPgFWwzQ/zFsxawUkVO8ZnaS+Z9YaUD nPKf3pQp2ldfgUeqMXvaMyTHWs2iHo5ucqNdYU6MaSR+HcJq2/kDNyMKBu/e1Rb1Qsx7 Se9DN2GxojvPH2uzP07yA+icrTDtCnWluCtXcZFIQgjB2TV9gA5wq3u6mVvl6xEtkiQ5 jPSg9S0merRNcSahaBqYqGMz8tfQEJ0xghRzjzTMoSC/f7bWSAF6aWWUTRg2YFMpePvD I2IQ== 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:mime-version :content-disposition:user-agent; bh=mHbZ4xPUa2e8Z9ySz/Reqmt5mff2C3fDEKHsxtsl+2U=; b=SthF24jShzEyXVIjfNRQWBtZdJv/YBuElo1Etmn3v9bManWIeUHe/50fEbv4KvPhiW DW0XvDms65ldQqevC4T31U8SomMjBclFiR/PYHeUzL6OUBCTeAm3hOfqKGau8TfLtnR3 Mwk2SmHW9u5PGqxByOooiuguaH6HaDJsGRC6HBLsj3Q+vc3NgwKn0s1fz7xU2xqOnQTg kBjUx07ym/8xMpQ1/PHl1Ml3AHzM6OQahVaw6Q9vnUp/nXIC/P9cPqIl9EwIc+ALJAQ4 RIGiW+38aV3haZ5zsqr/ROuDBO3Rnvwe/ic9yNojPNn240M6so8GyLm/Fj/L5IkCl+iP G9bw== X-Gm-Message-State: AGi0PuYjUU5pRjqYzO3nJVUS/dOEpy4e32d3rPBZiUm2OXARXplbwibQ 6r+5F5BlcnctP3zSdkXF/Tg= X-Google-Smtp-Source: APiQypLqZB8c/0OOLESufN7X24rZd9dVPY3QUBPGYqD1m6YtzXJwbEzRVL9gYijJiRQav0HHP9rS2g== X-Received: by 2002:a17:90a:1ae9:: with SMTP id p96mr13624264pjp.75.1587841209653; Sat, 25 Apr 2020 12:00:09 -0700 (PDT) Received: from syed ([106.223.101.50]) by smtp.gmail.com with ESMTPSA id ie17sm7574431pjb.19.2020.04.25.12.00.03 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 25 Apr 2020 12:00:09 -0700 (PDT) Date: Sun, 26 Apr 2020 00:29:59 +0530 From: Syed Nayyar Waris To: akpm@linux-foundation.org Cc: andriy.shevchenko@linux.intel.com, vilhelm.gray@gmail.com, michal.simek@xilinx.com, arnd@arndb.de, rrichter@marvell.com, linus.walleij@linaro.org, bgolaszewski@baylibre.com, yamada.masahiro@socionext.com, rui.zhang@intel.com, daniel.lezcano@linaro.org, amit.kucheria@verdurent.com, linux-arch@vger.kernel.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org Subject: [PATCH v2 0/6] Introduce the for_each_set_clump macro Message-ID: MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org This patchset introduces a new generic version of for_each_set_clump. The previous version of for_each_set_clump8 used a fixed size 8-bit clump, but the new generic version can work with clump of any size but less than or equal to BITS_PER_LONG. The patchset utilizes the new macro in several GPIO drivers. The earlier 8-bit for_each_set_clump8 facilitated 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. But with the new for_each_set_clump the clump size can be different from 8 bits. Moreover, the clump can be split at word boundary in situations where word size is not multiple of clump size. Following are examples showing the working of new macro for clump sizes of 24 bits and 6 bits. Example 1: clump size: 24 bits, Number of clumps (or ports): 10 bitmap stores the bit information from where successive clumps are retrieved. /* bitmap memory region */ 0x00aa0000ff000000; /* Most significant bits */ 0xaaaaaa0000ff0000; 0x000000aa000000aa; 0xbbbbabcdeffedcba; /* Least significant bits */ Different iterations of for_each_set_clump:- 'offset' is the bit position and 'clump' is the 24 bit clump from the above bitmap. Iteration first: offset: 0 clump: 0xfedcba Iteration second: offset: 24 clump: 0xabcdef Iteration third: offset: 48 clump: 0xaabbbb Iteration fourth: offset: 96 clump: 0xaa Iteration fifth: offset: 144 clump: 0xff Iteration sixth: offset: 168 clump: 0xaaaaaa Iteration seventh: offset: 216 clump: 0xff Loop breaks because in the end the remaining bits (0x00aa) size was less than clump size of 24 bits. In above example it can be seen that in iteration third, the 24 bit clump that was retrieved was split between bitmap[0] and bitmap[1]. This example also shows that 24 bit zeroes if present in between, were skipped (preserving the previous for_each_set_macro8 behaviour). Example 2: clump size = 6 bits, Number of clumps (or ports) = 3. /* bitmap memory region */ 0x00aa0000ff000000; /* Most significant bits */ 0xaaaaaa0000ff0000; 0x0f00000000000000; 0x0000000000000ac0; /* Least significant bits */ Different iterations of for_each_set_clump: 'offset' is the bit position and 'clump' is the 6 bit clump from the above bitmap. Iteration first: offset: 6 clump: 0x2b Loop breaks because 6 * 3 = 18 bits traversed in bitmap. Here 6 * 3 is clump size * no. of clumps. Syed Nayyar Waris (6): bitops: Introduce the the for_each_set_clump macro lib/test_bitmap.c: Add for_each_set_clump test cases gpio: thermal: Utilize for_each_set_clump macro bitops: Remove code related to for_each_set_clump8 gpio: thunderx: Utilize for_each_set_clump macro gpio: xilinx: Utilize for_each_set_clump macro drivers/gpio/gpio-104-dio-48e.c | 8 +-- drivers/gpio/gpio-104-idi-48.c | 4 +- drivers/gpio/gpio-74x164.c | 4 +- drivers/gpio/gpio-gpio-mm.c | 8 +-- drivers/gpio/gpio-max3191x.c | 4 +- drivers/gpio/gpio-pca953x.c | 4 +- drivers/gpio/gpio-pci-idio-16.c | 8 +-- drivers/gpio/gpio-pcie-idio-24.c | 8 +-- drivers/gpio/gpio-pisosr.c | 4 +- drivers/gpio/gpio-thunderx.c | 12 ++-- drivers/gpio/gpio-uniphier.c | 4 +- drivers/gpio/gpio-ws16c48.c | 8 +-- drivers/gpio/gpio-xilinx.c | 64 +++++++++-------- drivers/thermal/intel/intel_soc_dts_iosf.c | 6 +- include/asm-generic/bitops/find.h | 12 ++-- include/linux/bitmap.h | 60 +++++++++++----- include/linux/bitops.h | 9 +-- lib/find_bit.c | 12 ++-- lib/test_bitmap.c | 108 ++++++++++++++++++++++------- 19 files changed, 220 insertions(+), 127 deletions(-)