From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 CFF011DE3DC for ; Sun, 23 Nov 2025 15:24:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763911466; cv=none; b=kYhEiOd42vbkTDeKOEiH1DYVI7plgOBuO1Pd6QWrKaXXrQT+NjLZALpVIESTA1f6hMCl5RaZT1NohlrWj6iUdSUmCMjnRRPdkOl4j2KB0P16kOGSBzr402L+M9QmCSNuX/sAjtiZgxkVVc4b9Xrcdj6T3CYKWqp6ErdnxmT/rao= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763911466; c=relaxed/simple; bh=Bt4lvQ5tWEOJMSObtokBzF/TdUkPAMNtm/HTu/psEx8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jMVPydXaTK8NOaSACcmyLsdY/uZOk9K0yPfW07bNjtaR0T5t/mVe4upzhJvr4CpwdYmsQdt4vuMle/mATRj4RqYAhuXLXX1JbnZUkWYyoEMu7JBO3+IsfYuR8UsTx4hFAYrorFTcSfrsYMdwmYSovAvzrdhXqBalFSkDzjluG1I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=EbflPeNF; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="EbflPeNF" Received: from pendragon.ideasonboard.com (fs276ed015.tkyc509.ap.nuro.jp [39.110.208.21]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 14DAC606; Sun, 23 Nov 2025 16:22:12 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1763911334; bh=Bt4lvQ5tWEOJMSObtokBzF/TdUkPAMNtm/HTu/psEx8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EbflPeNFP+y3b2qf6OOI8rlkd4xuRtz3rnSvaLoxbJc7QwPSAj9g9f4RbBbvzsWYj ywbEhANIfkrXp4Qlydvquw1AKvpUWP9AcF5yryvcgR/kNxeQyPsw45FgL5BQrsWs75 r3mIuS3NNd5uQeKwXr6D7jpRiiMmj2atu6ETuvag= Date: Mon, 24 Nov 2025 00:23:56 +0900 From: Laurent Pinchart To: "Russell King (Oracle)" Cc: Wei Fang , Clark Wang , Oleksij Rempel , Emanuele Ghidoli , "devicetree@vger.kernel.org" , "imx@lists.linux.dev" , "linux-arm-kernel@lists.infradead.org" , Daniel Scally , Kieran Bingham , Stefan Klug , Conor Dooley , Fabio Estevam , Krzysztof Kozlowski , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo Subject: Re: [PATCH] arm64: dts: imx8mp-debix-model-a: Disable EEE for 1000T Message-ID: <20251123152356.GF15447@pendragon.ideasonboard.com> References: <20251112222551.GB9135@pendragon.ideasonboard.com> <20251113010627.GC9135@pendragon.ideasonboard.com> <20251114222654.GI30434@pendragon.ideasonboard.com> <20251122072246.GA16239@pendragon.ideasonboard.com> <20251123053802.GA25329@pendragon.ideasonboard.com> Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Sun, Nov 23, 2025 at 08:52:00AM +0000, Russell King (Oracle) wrote: > On Sun, Nov 23, 2025 at 02:38:02PM +0900, Laurent Pinchart wrote: > > On Sat, Nov 22, 2025 at 09:57:49AM +0000, Russell King (Oracle) wrote: > > > On Sat, Nov 22, 2025 at 04:22:46PM +0900, Laurent Pinchart wrote: > > > > Hello Wei, > > > > > > > > On Tue, Nov 18, 2025 at 01:50:55AM +0000, Wei Fang wrote: > > > > > Sorry, I only have a little experience with DWMac, add Clark to help look > > > > > at this issue. > > > > > > > > Thank you. > > > > > > > > I think we're getting close to having a good understanding of the > > > > problem. I've debugged it as far as I could based on the information > > > > available publicly. Let's try to get to the bottom of this issue, it > > > > impacts quite a lot of people and it would be very nice to fix it > > > > properly in mainline. > > > > > > > > The short summary is that I'm experiencing an interrupt storm on IRQ 135 > > > > when EEE is enabled with the EQOS interface. > > > > > > > > My current theory is that > > > > > > > > - The lpi_intr_o signal of the EQOS is OR'ed into IRQ 135. > > > > - The issue is triggerted by the PHY exiting LPI mode > > > > - When it exits LPI mode, the PHY restarts generating the RX clock > > > > (clk_rx_i). > > > > - The MAC detects exit from LPI, and asserts lpi_intr_o. > > > > - Before the CPU has time to process the interrupt, the PHY enters LPI > > > > mode again, and stops generating the RX clock. > > > > - The CPU processes the interrupt and reads the GMAC4_LPI_CTRL_STATUS > > > > registers. This does not clear lpi_intr_o as there's no clk_rx_i. > > > > > > Please try setting STMMAC_FLAG_RX_CLK_RUNS_IN_LPI in dwmac-imx.c and > > > see whether that changes the behaviour. > > > > I have tested that and it worked like a charm ! I have submitted > > https://lore.kernel.org/r/20251123053518.8478-1-laurent.pinchart@ideasonboard.com > > > > That was quite an adventure. Thank you so much for all your support, I'm > > not sure I would have managed without you (or at least I would have > > needed way more time). I really really appreciate it. > > > > If the above patch gets accepted, we will probably be able to remove the > > eee-broken-* properties from the i.MX8MP device tree files (and possibly > > from i.MX8DXL and i.MX93 as well). I have mentioned that below the > > commit message of the patch, with a test procedure as it should be > > tested on each board. > > As stated in reply to that patch, while this may reduce the severity of > the storm, I don't think it'll completely eliminate it. > > I made the suggestion to set the flag as a test to confirm whether the > lpi_intr_o is indeed the problem by ensuring that the receive domain is > always clocked, and thus ensuring that the signal clears within four > clock cycles, rather than an indefinite period should the remote end > re-enter LPI mode quicky. You're right. I've checked replied to the patch with the following numbers. 100TX link, eee-broken-* set: 7000 interrupts 1000T link, eee-broken-* set: 2711 interrupts 100TX link, eee-broken-* unset: 9450 interrupts 1000T link, eee-broken-* unset: 6066 interrupts -- Regards, Laurent Pinchart