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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 966DFD4A5F5 for ; Sat, 17 Jan 2026 19:25:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=byvU+Z3sKPrJnBmL2J9V1FBYguxPPUdGWa9Tg9yCs4Q=; b=nV8TOwf7iZ7AzzLpwp1YC5V4// 9zGyikXWcuLR9dxp+/DGiZ+21IUvDrMcEr8UCXmEtTLnwfoaBntI3dTfo1LeO2s62VUPPciF/K9QN xM0FsKl3dn8rvgCUXlhjCcBZfOdeURIv7AQVysAtkBXfUqavfMyKLRw0D2cXVMinetmp9GgE6Bj8t PT/ifoGsTS9o8WLtD7HTTuCw/cmSqWyBI3OloFLnwiN/Dgb9kJWp3L0i5rV9HZQPvBVjHzpKadztH PXsmfHMtSdSDQcPvZQ2/rglGLmmw49P58TvHXUEpSO4bdI0sw9+8o5AHplwtGdEu6ElloL5COPnZd emu29Zmw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vhBv6-0000000Fld7-1uGp; Sat, 17 Jan 2026 19:25:12 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vhBv3-0000000Flca-37i9 for linux-arm-kernel@lists.infradead.org; Sat, 17 Jan 2026 19:25:11 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 3060242A24; Sat, 17 Jan 2026 19:25:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0BB18C4CEF7; Sat, 17 Jan 2026 19:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768677906; bh=tTZl9CX+1jUu6Qu7S8Vamek8DWf6OLGlE/QCQzYqkuI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=IySncHSiD1lX4N21BoUm89LJXXfYt4r74HJN2+4Z1tEUa+I9QI978Cut9cJqp08qh aP+WScfwchF2f6SNtc4v/Q673kJ5rufRLHxPoZ72dnjK1qnLDEsGRG7cGgggqigvrB mXM+QLj0kI/77QoyCWld32kmWb1unpBTeikJFqWLWYYzSkm0XY+9/0fPaKXbSMmhzo 3FYPaCqmdAkZQQrgmEwU62GHJanv4hWEF1BmdLivxQ+deyfM/sBInaIyLBRwB3D8uc eAvuKdLONkslXVQI/vWp0qeABKx4StvrknmjZ5+UT1CQYvaLj06inA+miPC/htdik5 Dj2Dghtkkvxqw== Message-ID: Date: Sat, 17 Jan 2026 20:25:01 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/3] clk: samsung: allow runtime PM with auto clock gating To: =?UTF-8?Q?Andr=C3=A9_Draszik?= , Sylwester Nawrocki , Chanwoo Choi , Alim Akhtar , Michael Turquette , Stephen Boyd Cc: Peter Griffin , Tudor Ambarus , Will McVicker , Juan Yescas , linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20260109-clk-samsung-autoclk-updates-v1-0-2394dcf242a9@linaro.org> <20260109-clk-samsung-autoclk-updates-v1-3-2394dcf242a9@linaro.org> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGVBBMBCgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJoF1BKBQkWlnSaAAoJEBuTQ307 QWKbHukP/3t4tRp/bvDnxJfmNdNVn0gv9ep3L39IntPalBFwRKytqeQkzAju0whYWg+R/rwp +r2I1Fzwt7+PTjsnMFlh1AZxGDmP5MFkzVsMnfX1lGiXhYSOMP97XL6R1QSXxaWOpGNCDaUl ajorB0lJDcC0q3xAdwzRConxYVhlgmTrRiD8oLlSCD5baEAt5Zw17UTNDnDGmZQKR0fqLpWy 786Lm5OScb7DjEgcA2PRm17st4UQ1kF0rQHokVaotxRM74PPDB8bCsunlghJl1DRK9s1aSuN hL1Pv9VD8b4dFNvCo7b4hfAANPU67W40AaaGZ3UAfmw+1MYyo4QuAZGKzaP2ukbdCD/DYnqi tJy88XqWtyb4UQWKNoQqGKzlYXdKsldYqrLHGoMvj1UN9XcRtXHST/IaLn72o7j7/h/Ac5EL 8lSUVIG4TYn59NyxxAXa07Wi6zjVL1U11fTnFmE29ALYQEXKBI3KUO1A3p4sQWzU7uRmbuxn naUmm8RbpMcOfa9JjlXCLmQ5IP7Rr5tYZUCkZz08LIfF8UMXwH7OOEX87Y++EkAB+pzKZNNd hwoXulTAgjSy+OiaLtuCys9VdXLZ3Zy314azaCU3BoWgaMV0eAW/+gprWMXQM1lrlzvwlD/k whyy9wGf0AEPpLssLVt9VVxNjo6BIkt6d1pMg6mHsUEVzsFNBFVDXDQBEADNkrQYSREUL4D3 Gws46JEoZ9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLue MNsWLJBvBaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6ei OMheesVS5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wA GldWsRxbf3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA 6z6lBZn0WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9 YegxWKvXXHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt 91pFzBSOIpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gU BLHFTg2hYnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/ JoFzZ4B0p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu 4vXVFBYIGmpyNPYzRm0QPwARAQABwsF8BBgBCgAmAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtB YpsFAmgXUF8FCRaWWyoACgkQG5NDfTtBYptO0w//dlXJs5/42hAXKsk+PDg3wyEFb4NpyA1v qmx7SfAzk9Hf6lWwU1O6AbqNMbh6PjEwadKUk1m04S7EjdQLsj/MBSgoQtCT3MDmWUUtHZd5 RYIPnPq3WVB47GtuO6/u375tsxhtf7vt95QSYJwCB+ZUgo4T+FV4hquZ4AsRkbgavtIzQisg Dgv76tnEv3YHV8Jn9mi/Bu0FURF+5kpdMfgo1sq6RXNQ//TVf8yFgRtTUdXxW/qHjlYURrm2 H4kutobVEIxiyu6m05q3e9eZB/TaMMNVORx+1kM3j7f0rwtEYUFzY1ygQfpcMDPl7pRYoJjB dSsm0ZuzDaCwaxg2t8hqQJBzJCezTOIkjHUsWAK+tEbU4Z4SnNpCyM3fBqsgYdJxjyC/tWVT AQ18NRLtPw7tK1rdcwCl0GFQHwSwk5pDpz1NH40e6lU+NcXSeiqkDDRkHlftKPV/dV+lQXiu jWt87ecuHlpL3uuQ0ZZNWqHgZoQLXoqC2ZV5KrtKWb/jyiFX/sxSrodALf0zf+tfHv0FZWT2 zHjUqd0t4njD/UOsuIMOQn4Ig0SdivYPfZukb5cdasKJukG1NOpbW7yRNivaCnfZz6dTawXw XRIV/KDsHQiyVxKvN73bThKhONkcX2LWuD928tAR6XMM2G5ovxLe09vuOzzfTWQDsm++9UKF a/A= In-Reply-To: <20260109-clk-samsung-autoclk-updates-v1-3-2394dcf242a9@linaro.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260117_112509_832877_DE5C612C X-CRM114-Status: GOOD ( 26.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 09/01/2026 18:27, André Draszik wrote: > When automatic clock gating is enabled, runtime PM (RPM) isn't entered > even if enabled for a CMU if a sysreg clock exists and is provided by > this CMU (as is generally the case). > > The reason is that this driver acquires a CMU's sysreg registers using > syscon_regmap_lookup_by_phandle() which ends up preparing the sysreg > clock. Given the sysreg clock is provided by this CMU, this CMU's usage > count is therefore bumped and RPM can not be entered as this CMU never > becomes idle. > > Switch to using device_node_to_regmap() which doesn't handle resources > (the clock), leaving the CMU's usage count unaffected. > > Note1: sysreg clock handling is completely removed with this commit I miss where do you remove in this commit the sysreg clock handling? > because sysreg register access is only required during suspend/resume. > In the runtime suspend case, we would have to enable the clock to read > the registers, but we can not do that as that would cause a resume of > this driver which is not allowed. This is not a problem because we > would only need to handle the clock manually if automatic clock gating > wasn't enabled in the first. This code is only relevant if automatic > clock gating is enabled, though. > > Fixes: 298fac4f4b96 ("clk: samsung: Implement automatic clock gating mode for CMUs") > Signed-off-by: André Draszik > --- > drivers/clk/samsung/clk.c | 92 +++++++++++++++++++++++++++++++++++------------ > drivers/clk/samsung/clk.h | 2 ++ > 2 files changed, 71 insertions(+), 23 deletions(-) > > diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c > index 9f68f079fd552f8dfb6898dbfb47dec0e84c626c..6515df81fcbc79b90f5262843e67575f6a4e0dda 100644 > --- a/drivers/clk/samsung/clk.c > +++ b/drivers/clk/samsung/clk.c > @@ -9,11 +9,13 @@ > */ > > #include > +#include > #include > #include > #include > #include > #include > +#include > #include > #include > #include > @@ -489,6 +491,50 @@ void __init samsung_cmu_register_clocks(struct samsung_clk_provider *ctx, > samsung_clk_register_cpu(ctx, cmu->cpu_clks, cmu->nr_cpu_clks); > } > > +static int samsung_get_sysreg_regmap(struct device_node *np, > + struct samsung_clk_provider *ctx) > +{ > + struct device_node *sysreg_np; > + struct clk *sysreg_clk; > + struct regmap *regmap; > + int ret; > + > + sysreg_np = of_parse_phandle(np, "samsung,sysreg", 0); > + if (!sysreg_np) > + return -ENODEV; > + > + sysreg_clk = of_clk_get(sysreg_np, 0); I don't think you should be poking clock of some other device. This clearly breaks encapsulation. What sysreg is needs to do to access registers, is only business of sysreg. No other drivers should re-implement this. > + if (IS_ERR(sysreg_clk)) { > + ret = PTR_ERR(sysreg_clk); > + /* clock is optional */ > + if (ret != -ENOENT) { > + pr_warn("%pOF: Unable to get sysreg clock: %d\n", np, > + ret); > + goto put_sysreg_np; > + } > + sysreg_clk = NULL; > + } Best regards, Krzysztof