From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgjp3.qq.com (smtpbgjp3.qq.com [54.92.39.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E1F983B3884 for ; Fri, 11 Sep 2026 02:04:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.92.39.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789092260; cv=none; b=SNKWX0T31XYZSkLQwBb1rgAp/IBrZO4psLd27gFNTdjBJt3u/7Psnd7nOKbPAadDey7dkQ8LldCRe3rF5qWYOOYjF1WAiJsW7Ebw/dVqlID6TWaOuuxHRgB5dht5Mq2SsRTbTEnewqph37dno/9uFQJKbZPOOwOXvw2dzYRk2YM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789092260; c=relaxed/simple; bh=p4+ap8iN4dSSeNIC2F+epq8WIYVdpPuH33P0vIVK/GU=; h=Mime-Version:Content-Type:Date:Message-Id:Subject:From:To:Cc: References:In-Reply-To; b=q8p9XaLu72kK90bZ+urdkY23TpQ3qRYDJh3PJIuRb3rWIARvrIHMedbWaH9oil56hw2XyXpkODrphfhDsNeQeLnXfR4WWhRv4cCvvJUXRK7+J7SshFSol3UoLnCHp3EXeERP0CFuuvzeHMcfG8C53EJHE+NJy2Xo0cSL27I7vkw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.spacemit.com; spf=none smtp.mailfrom=linux.spacemit.com; dkim=pass (1024-bit key) header.d=linux.spacemit.com header.i=@linux.spacemit.com header.b=ciCR84JG; arc=none smtp.client-ip=54.92.39.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.spacemit.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.spacemit.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.spacemit.com header.i=@linux.spacemit.com header.b="ciCR84JG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.spacemit.com; s=mxsw2412; t=1789092180; bh=p4+ap8iN4dSSeNIC2F+epq8WIYVdpPuH33P0vIVK/GU=; h=Mime-Version:Date:Message-Id:Subject:From:To; b=ciCR84JG8J45yBUMsDQsuJUMc6ABdMe+Z2YL6pHg+/rt9iwLkcOBEnQ++YAoT8y90 TVyUMKVYB80dNJLA9W/ZVz46y6lV5uoehYp2uCwYx+9B/g4N9U4o9826wF3uUb4igI KMhiDlJ0VKJDgnRJJj+xcTzBRMLJ36BOuSVRfSOs= X-QQ-mid: esmtpsz19t1789092172t4f8b07e9 X-QQ-Originating-IP: aSvGHA2+aoIKS3fHxwTlfYEZdf0xYuWX7HM/PfxhtbM= Received: from = ( [120.237.158.181]) by bizesmtp.qq.com (ESMTP) with id ; Fri, 11 Sep 2026 10:02:50 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 10264822679062085663 EX-QQ-RecipientCnt: 13 Precedence: bulk X-Mailing-List: linux-clk@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: multipart/signed; boundary=215ee3cf27d68f54324eca2221f65eb243d448b430723bfe53a69c3edd9e; micalg=pgp-sha512; protocol="application/pgp-signature" Date: Fri, 11 Sep 2026 10:02:47 +0800 Message-Id: Subject: Re: [PATCH 4/5] clk: spacemit: reject rate changes to running firmware PLLs From: "Troy Mitchell" To: "Yao Zi" , "Troy Mitchell" , "Stephen Boyd" , "Brian Masney" , "Jerome Brunet" , "Yixun Lan" , "Alex Elder" , "Inochi Amaoto" , "Haylen Chu" Cc: , , , X-Mailer: aerc 0.21.0-0-g5549850facc2 References: <20260909-spacemit-pll-init-v1-0-b3065ad5a4ac@linux.spacemit.com> <20260909-spacemit-pll-init-v1-4-b3065ad5a4ac@linux.spacemit.com> In-Reply-To: X-QQ-SENDSIZE: 520 Feedback-ID: esmtpsz:linux.spacemit.com:qybglogicsvrgz:qybglogicsvrgz3a-0 X-QQ-XMAILINFO: ND42uzdxTIzrAUXRIQvKYrDAXR9xjCPK2SxrDkBOF/Ht8IhQa4fdQXo5 siNFl6sCpD4Cnn7FqEYx8IacMqqy26AJrkNM2hMaoH1URoLv46oyJYlo/JtxHQ4zT48UXaw o6+6Wc6TwK+SZrxKTnG5LQw6oTRn9SiuhMpsA5bT6dnNOxMZLPDR1tZMIO8PLNeKm7rQB1A Bea/gsjFkFeDoQqcYaymbudKKXnpL488FCdo/BqHBzH43kzPv2DeBgSKkmVDQ+ZwTQo5fAu D0z76ghwqxsKdvf5eprwylYrnObBBQ93vRKJFFtjpGbKqRxRSyD003LhPubrhDjtKAjeACj EJ4QXfL2RZH0gbBkw2tr68zTzfHa4EkaaGNpYR1tTBVQ1fJkDP0dzl51Eb6Z2ljo+TTzio/ 2C7crv0vxaG5T7xtWOL2DhfSkch4JglXeZK2uZpEBeHB7u2BBwmEOhkygXledXvSwG6wvGk KZVy20AafBQ/2+GHQK+jDcZ8NoAmZmLu5QWJ4KSXUS3pbzSw0a+9pXulN4cUqQO4tm5ogx+ jIQIg7tz/LXOW0Grq4lbwASWrtZIb9I4FohidJXd096q9s3bQzpms9+pd4ylJpnvbtI9xf9 S6JirXSa1uN3riJFxMqru7lIVAEjNcDUKXMEKAF7JrBHxiRzxo5zl3Rql4K96ZEMbgyVgFy B3nOGaU6ccxpwISJMt6wNyUeSKUAxOx+UkgYfbUaD7vFTrhnMvMztlfY6c+XBCgygpe1LJC pfoplvrxti0sqLro5HFCNBUghn7JSbRM/VvblNpJ27DrbBOY0UCu5dM8oOTKrbjQHqvpOCT F+ApYaqBIM6BCkOxh1Kx39N0zM0NHeOmdxoF9e50xq9POgTHalifb2gZu+VJ5iQ5+MeS4ah esXFaXh6WasB1LivaAImsXrfAriehAZwcnwLMTrKPP9wAPfaWGPEuhcxIHHTCNjJlpBnM0g lwQxfP4R36xKBFiB3u1umhVTeIgiA3xR27o+gLzOGpowxaDFLWf3WW53Bq3/ZMaVVZTNycp jlK55kkRPNIebTzd4bXGRZbYw6PYaLoVNC7lEYAFKpveAhZ2D5id8rn2c6gl0= X-QQ-XMRINFO: MSVp+SPm3vtSI1QTLgDHQqIV1w2oNKDqfg== X-QQ-RECHKSPAM: 0 --215ee3cf27d68f54324eca2221f65eb243d448b430723bfe53a69c3edd9e Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 On Thu Sep 10, 2026 at 9:31 PM +08, Yao Zi wrote: > On Wed, Sep 09, 2026 at 10:07:04PM +0800, Troy Mitchell wrote: >> CLK_SET_RATE_GATE only protects clocks prepared through CCF. A PLL left >> running by firmware can have a zero prepare count, so this flag alone >> cannot prevent set_rate() from reprogramming a live PLL. > > Would it be a better idea to simply turn off the PLL before reprogramming= , > since protected by CLK_SET_RATE_GATE, re-programming never happens when > the PLL is required by downstream? This also seems to be simpler. Then assigned-clock-rates on the PLL provider node? I tested this on K3: .set_rate() was called during provider registration, with PLL3's prepare count still zero while the CPUs were running on it. Disabling PLL3 hung the board. CLK_SET_RATE_GATE therefore does not protect users that CCF has not yet accounted for. --=20 Troy Mitchell --215ee3cf27d68f54324eca2221f65eb243d448b430723bfe53a69c3edd9e Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iIMEABYKACsWIQSL4Ay2cExaPXAQcU2YCe+A+TM0LwUCaqNhRw0caUB0cm95LXku b3JnAAoJEJgJ74D5MzQvFiQA/1yR1e1N5dqm/JjKEw3dfM8yjqKmhTeY4evjauQO 6r/JAQC+EVD4ZL95QJzBkQT+HKp2w5tll5d/gI8NIB1sW9JeDg== =Z8ol -----END PGP SIGNATURE----- --215ee3cf27d68f54324eca2221f65eb243d448b430723bfe53a69c3edd9e--