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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 02120C48BDF for ; Tue, 22 Jun 2021 21:05:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE77E61001 for ; Tue, 22 Jun 2021 21:05:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230046AbhFVVHY (ORCPT ); Tue, 22 Jun 2021 17:07:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229629AbhFVVHX (ORCPT ); Tue, 22 Jun 2021 17:07:23 -0400 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64886C061574; Tue, 22 Jun 2021 14:05:07 -0700 (PDT) Received: by mail-ej1-x631.google.com with SMTP id he7so458412ejc.13; Tue, 22 Jun 2021 14:05:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=UUc+wnGu+qMMod+izmu7YMTZnrpqEfnlG0hnSla1RfI=; b=MhqOn4tLoi01in/oJrMFsXHKfK91kconn54gNEDCGTEr+NqA/5XMsHzTB8B/YRC01f EUAJdfEFssAK3vB6ngsO4VzbFE0xn/4SA/xSaOs1s9ql4pP17uvZOqAdxUtbvNJ7eBJy cEKLv94QzwJYODppWCl4gbxuH8g4boCwlljHBJuvTvTEeZhi97ooK73FDtI5+l6VCBwe 2FtW/p7rLb1EwMnKr6DLTl1U9aPcEGJDG7iXTayW6TWbGFJexCfI47aDX7j3vLr/IBKX 7NJBYwoBchWmz/NJ5q2DLl0YPmiD6ZSg0hITOb6Ev1KAoU7djRN4oLYAy6cL3v3rLGYu +zrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=UUc+wnGu+qMMod+izmu7YMTZnrpqEfnlG0hnSla1RfI=; b=tktrx6MKyGv6THMnLKOBsrj1DNlPoFMqihSlL0fa9mYY/Bqw1oSWMDUbaa7+4PKb93 ky38aubbxis/DFCkIiWia60ftb3vldAFIJjudZj9CO7F0j8t5erE7xXsZ/lu3qYspw4s Ov+JEya+by8IA3qrajJI4sLDajIgwGcBIq1Xq2WPzrWwcG0ol++cCMVKYRYNALlkOtte YE67WcXsixQbjDUKV6a3g84BSuoAr58YhCm9dwOkWOJPPemgZVAbmWNPaW4+rQizr0o6 KJDRlFgIG5cVBdZaoVjGvRU+xAVxlgrZgdcv8s3YiAA2s95R2FPMFAHJ/cmjqU7lXdHn 1zcg== X-Gm-Message-State: AOAM533VUu/IGKc8MMudNa2Rdi4/Y+P/URT3VJKRgzaNBDlKh1PUzI7u R6pkivHhlfY99Bg/mJephS6NOcERDtAOOOtAO+A= X-Google-Smtp-Source: ABdhPJwMewFnPfwv2MyXFnRt30omw+O65gF6+q13Lx/fCk9guSaZ8IKLEo+FvBPtL66HDFH7uMVWqojGhh/VRFlURTg= X-Received: by 2002:a17:906:3102:: with SMTP id 2mr1711516ejx.208.1624395906020; Tue, 22 Jun 2021 14:05:06 -0700 (PDT) MIME-Version: 1.0 References: <20210524103733.554878-1-martin.blumenstingl@googlemail.com> <1jr1heqhoy.fsf@starbuckisacylon.baylibre.com> In-Reply-To: <1jr1heqhoy.fsf@starbuckisacylon.baylibre.com> From: Martin Blumenstingl Date: Tue, 22 Jun 2021 23:04:55 +0200 Message-ID: Subject: Re: [PATCH v2 0/3] clk: meson: rounding for fast clocks on 32-bit SoCs To: Jerome Brunet , sboyd@kernel.org Cc: Neil Armstrong , mturquette@baylibre.com, khilman@baylibre.com, linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Stephen, On Mon, Jun 7, 2021 at 9:04 AM Jerome Brunet wrote: > > > On Fri 04 Jun 2021 at 19:18, Martin Blumenstingl wrote: > > > Hi Jerome, Hi Stephen, > > > > On Mon, May 24, 2021 at 12:37 PM Martin Blumenstingl > > wrote: > >> > >> On the 32-bit Amlogic Meson8/8b/8m2 SoCs we run into a problem with the > >> fast HDMI PLL and it's OD (post-dividers). This clock tree can run at > >> up to approx. 3GHz. > >> This however causes a problem, because these rates require BIT(31) to > >> be usable. Unfortunately this is not the case with clk_ops.round_rate > >> on 32-bit systems. BIT(31) is reserved for the sign (+ or -). > >> > >> clk_ops.determine_rate does not suffer from this limitation. It uses > >> an int to signal any errors and can then take all availble 32 bits for > >> the clock rate. > >> > >> Changes since v1 from [0]: > >> - reworked the first patch so the the existing > >> divider_{ro_}round_rate_parent implementations are using the new > >> divider_{ro_}determine_rate implementations to avoid code duplication > >> (thanks Jerome for the suggestion) > >> - added a patch to switch the default clk_divider_{ro_}ops to use > >> .determine_rate instead of .round_rate as suggested by Jerome > >> (thanks) > >> - dropped a patch for the Meson PLL ops as these are independent from > >> the divider patches and Jerome has applied that one directly (thanks) > >> - added Jerome's Reviewed-by to the meson clk-regmap patch (thanks!) > >> - dropped the RFC prefix > > please let me know what you think about this v2 > > I am asking because clk-divider is widely used, so I'd appreciate if > > this gets some time in linux-next (so for example Kernel CI can test > > this and report issues if there are any). Do you have any comments on this series? I am fine with it skipping 5.14 as it's a change which affects multiple platforms. So I would like to use the time until the trees are opening for patches targeting 5.15 to iron out code-review comments. > Looks good to me > Reviewed-by: Jerome Brunet Thanks Jerome - I'll add it to v3 once I send it (assuming nothing major changes) Best regards, Martin 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=-5.7 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 18CDDC2B9F4 for ; Tue, 22 Jun 2021 21:06:40 +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 D4F5B61001 for ; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Stephen, On Mon, Jun 7, 2021 at 9:04 AM Jerome Brunet wrote: > > > On Fri 04 Jun 2021 at 19:18, Martin Blumenstingl wrote: > > > Hi Jerome, Hi Stephen, > > > > On Mon, May 24, 2021 at 12:37 PM Martin Blumenstingl > > wrote: > >> > >> On the 32-bit Amlogic Meson8/8b/8m2 SoCs we run into a problem with the > >> fast HDMI PLL and it's OD (post-dividers). This clock tree can run at > >> up to approx. 3GHz. > >> This however causes a problem, because these rates require BIT(31) to > >> be usable. Unfortunately this is not the case with clk_ops.round_rate > >> on 32-bit systems. BIT(31) is reserved for the sign (+ or -). > >> > >> clk_ops.determine_rate does not suffer from this limitation. It uses > >> an int to signal any errors and can then take all availble 32 bits for > >> the clock rate. > >> > >> Changes since v1 from [0]: > >> - reworked the first patch so the the existing > >> divider_{ro_}round_rate_parent implementations are using the new > >> divider_{ro_}determine_rate implementations to avoid code duplication > >> (thanks Jerome for the suggestion) > >> - added a patch to switch the default clk_divider_{ro_}ops to use > >> .determine_rate instead of .round_rate as suggested by Jerome > >> (thanks) > >> - dropped a patch for the Meson PLL ops as these are independent from > >> the divider patches and Jerome has applied that one directly (thanks) > >> - added Jerome's Reviewed-by to the meson clk-regmap patch (thanks!) > >> - dropped the RFC prefix > > please let me know what you think about this v2 > > I am asking because clk-divider is widely used, so I'd appreciate if > > this gets some time in linux-next (so for example Kernel CI can test > > this and report issues if there are any). Do you have any comments on this series? I am fine with it skipping 5.14 as it's a change which affects multiple platforms. So I would like to use the time until the trees are opening for patches targeting 5.15 to iron out code-review comments. > Looks good to me > Reviewed-by: Jerome Brunet Thanks Jerome - I'll add it to v3 once I send it (assuming nothing major changes) Best regards, Martin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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=-5.7 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 AA025C2B9F4 for ; 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Tue, 22 Jun 2021 14:05:06 -0700 (PDT) MIME-Version: 1.0 References: <20210524103733.554878-1-martin.blumenstingl@googlemail.com> <1jr1heqhoy.fsf@starbuckisacylon.baylibre.com> In-Reply-To: <1jr1heqhoy.fsf@starbuckisacylon.baylibre.com> From: Martin Blumenstingl Date: Tue, 22 Jun 2021 23:04:55 +0200 Message-ID: Subject: Re: [PATCH v2 0/3] clk: meson: rounding for fast clocks on 32-bit SoCs To: Jerome Brunet , sboyd@kernel.org Cc: Neil Armstrong , mturquette@baylibre.com, khilman@baylibre.com, linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210622_140508_404517_14F8429B X-CRM114-Status: GOOD ( 29.90 ) X-BeenThere: linux-amlogic@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-amlogic" Errors-To: linux-amlogic-bounces+linux-amlogic=archiver.kernel.org@lists.infradead.org Hi Stephen, On Mon, Jun 7, 2021 at 9:04 AM Jerome Brunet wrote: > > > On Fri 04 Jun 2021 at 19:18, Martin Blumenstingl wrote: > > > Hi Jerome, Hi Stephen, > > > > On Mon, May 24, 2021 at 12:37 PM Martin Blumenstingl > > wrote: > >> > >> On the 32-bit Amlogic Meson8/8b/8m2 SoCs we run into a problem with the > >> fast HDMI PLL and it's OD (post-dividers). This clock tree can run at > >> up to approx. 3GHz. > >> This however causes a problem, because these rates require BIT(31) to > >> be usable. Unfortunately this is not the case with clk_ops.round_rate > >> on 32-bit systems. BIT(31) is reserved for the sign (+ or -). > >> > >> clk_ops.determine_rate does not suffer from this limitation. It uses > >> an int to signal any errors and can then take all availble 32 bits for > >> the clock rate. > >> > >> Changes since v1 from [0]: > >> - reworked the first patch so the the existing > >> divider_{ro_}round_rate_parent implementations are using the new > >> divider_{ro_}determine_rate implementations to avoid code duplication > >> (thanks Jerome for the suggestion) > >> - added a patch to switch the default clk_divider_{ro_}ops to use > >> .determine_rate instead of .round_rate as suggested by Jerome > >> (thanks) > >> - dropped a patch for the Meson PLL ops as these are independent from > >> the divider patches and Jerome has applied that one directly (thanks) > >> - added Jerome's Reviewed-by to the meson clk-regmap patch (thanks!) > >> - dropped the RFC prefix > > please let me know what you think about this v2 > > I am asking because clk-divider is widely used, so I'd appreciate if > > this gets some time in linux-next (so for example Kernel CI can test > > this and report issues if there are any). Do you have any comments on this series? I am fine with it skipping 5.14 as it's a change which affects multiple platforms. So I would like to use the time until the trees are opening for patches targeting 5.15 to iron out code-review comments. > Looks good to me > Reviewed-by: Jerome Brunet Thanks Jerome - I'll add it to v3 once I send it (assuming nothing major changes) Best regards, Martin _______________________________________________ linux-amlogic mailing list linux-amlogic@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-amlogic