From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D1A5C314D00 for ; Mon, 20 Oct 2025 13:24:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760966688; cv=none; b=lxhWwDqCc8hO7wCUwt9rn4XPO9AaRj0cRR0TPAAc5YSPe5XvNyulfv0mqo/j8dCG7vQZiU8BJVBJbQ3wqGR6fH9058XBN1rYN7i57moURdJltYK/5nGByw0Od6CiaulhgjsM/I8EcocE+gkdrqpNMFn7rPI8n45Ip2r1VvUaOeU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760966688; c=relaxed/simple; bh=57e2mVImHOH5lb+qBMy58ZLJTwYxPeo4lARKG2XJmLQ=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Gspsy9B/pxflQcJR7IXg93Eeh6DoBICeeVDAkZt7f+o/UopZL8WsPmq6ZEi05xC0wvI13R7z+aGLlgfk7iS8K4+86T5pJRV1w1y7jN4t5f9eGoKLp19dLkM2wyVubWO3iMR38wg5/st2CCojjsuX8ttAayQWFfKihBzEMxnEw0Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 609F71063; Mon, 20 Oct 2025 06:24:38 -0700 (PDT) Received: from donnerap.manchester.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 083B23F66E; Mon, 20 Oct 2025 06:24:44 -0700 (PDT) Date: Mon, 20 Oct 2025 14:24:34 +0100 From: Andre Przywara To: Jernej Skrabec Cc: wens@csie.org, samuel@sholland.org, mturquette@baylibre.com, sboyd@kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] clk: sunxi-ng: Mark A523 bus-r-cpucfg clock as critical Message-ID: <20251020142434.066f53b8@donnerap.manchester.arm.com> In-Reply-To: <20251019172647.80379-1-jernej.skrabec@gmail.com> References: <20251019172647.80379-1-jernej.skrabec@gmail.com> Organization: ARM X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.32; aarch64-unknown-linux-gnu) Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Sun, 19 Oct 2025 19:26:47 +0200 Jernej Skrabec wrote: > bus-r-cpucfg clock is important for peripheral which takes care for > powering CPU cores on and off. Since this operation is done by firmware > (TF-A), mark is as critical. That way Linux won't interfere with that > clock. Many thanks, makes sense. I hammered /sys/devices/system/cpu/cpu/online like a 1000 times in a random loop now, and it survived - after I excluded CPU0 from this. Offlining CPU0 works, but it doesn't come back online again. But that's probably something in TF-A, so nothing that affects this patch: > Fixes: 8cea339cfb81 ("clk: sunxi-ng: add support for the A523/T527 PRCM CCU") > Signed-off-by: Jernej Skrabec Reviewed-by: Andre Przywara Tested-by: Andre Przywara Cheers, Andre > --- > drivers/clk/sunxi-ng/ccu-sun55i-a523-r.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/clk/sunxi-ng/ccu-sun55i-a523-r.c b/drivers/clk/sunxi-ng/ccu-sun55i-a523-r.c > index 70ce0ca0cb7d..c5b0d4a2e397 100644 > --- a/drivers/clk/sunxi-ng/ccu-sun55i-a523-r.c > +++ b/drivers/clk/sunxi-ng/ccu-sun55i-a523-r.c > @@ -125,7 +125,7 @@ static SUNXI_CCU_GATE_HW(bus_r_dma_clk, "bus-r-dma", > static SUNXI_CCU_GATE_HW(bus_r_rtc_clk, "bus-r-rtc", > &r_apb0_clk.common.hw, 0x20c, BIT(0), 0); > static SUNXI_CCU_GATE_HW(bus_r_cpucfg_clk, "bus-r-cpucfg", > - &r_apb0_clk.common.hw, 0x22c, BIT(0), 0); > + &r_apb0_clk.common.hw, 0x22c, BIT(0), CLK_IS_CRITICAL); > > static struct ccu_common *sun55i_a523_r_ccu_clks[] = { > &r_ahb_clk.common,