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 506ADC54E66 for ; Wed, 13 Mar 2024 15:05:10 +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=08xa12eFgF24Q/HExgdKesRSK158jc76k5/A1mMD/dI=; b=aq+TGwN8u/ByVBw+bhbXTPaEM0 NsTEKo7FaIXZ7aJOiocThCfaHDU5B/ZEq+yFxgmlAhESCiC/BLg6DDteJmOt/jC2SSlhKMmbyOpbs ChsI4RrpgC1mrTXuaYMqBpgVHa6MgIoUq0pVGSFbAP44ETSJwP6H4UvdwCK5YtEArlngvKKOy8/Tl PUfnKwiyXHfaPsi2EyUipkWesEyQjotpeTX98x27AUHgFfxpebUUc1Dp1sXE+gSsNrIUNbaSDXXvz CRIYitVTqq+tyWdTb4sm1EXd+s4X3uEQZFGQYtoj3w2hRE9uzwPzDEb6BkLUd6d/IzzY6ZmhTNWTc CPR9VQ/Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rkQAH-0000000AXSG-31CI; Wed, 13 Mar 2024 15:05:09 +0000 Received: from relay6-d.mail.gandi.net ([217.70.183.198]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rkQAC-0000000AXPn-4AAA; Wed, 13 Mar 2024 15:05:07 +0000 Received: by mail.gandi.net (Postfix) with ESMTPSA id 42A22C0012; Wed, 13 Mar 2024 15:04:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arinc9.com; s=gm1; t=1710342301; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=08xa12eFgF24Q/HExgdKesRSK158jc76k5/A1mMD/dI=; b=bpQnl2O53b8VNslubfwlRrs7ImLhnBZRI9miQ9brL4i/HTzsv/LTAj56RocdLqLJLKoGny DldxBahLEeGZIYaq6nGvwweoK0RZxxCAGLpB3lUtGBxr0vzg+NePAaMp5QVbvGeTNOhXqY 0Bd51c+TdsuD0Xjs5lcutZp/YDpwzN3sia8HmJD1NJugiryFPoXi2WHCYtKZMEdjrK+6fD VZPX8G0BRxGd4xbw+VUiAMm15m4hi8RtDQ469an0lQU4Vpbaar4bHRzELsSYqWlM8guE4I DzGIwsu9iTOhSFm8iVlcemcECjbo8FTzHz/PTrGBZW08zaCt2UjiroNmPTWaMQ== Message-ID: <997db446-030b-4e6a-beea-0ae7d990e7e2@arinc9.com> Date: Wed, 13 Mar 2024 18:04:43 +0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] net: dsa: mt7530: increase reset hold time To: Justin Swartz Cc: Daniel Golle , DENG Qingfang , Sean Wang , Andrew Lunn , Florian Fainelli , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org References: <20240312192117.7789-1-justin.swartz@risingedge.co.za> <2640a495-97a0-4669-a53a-e367af956a78@arinc9.com> Content-Language: en-US From: =?UTF-8?B?QXLEsW7DpyDDnE5BTA==?= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-GND-Spam-Score: 400 X-GND-Status: SPAM X-GND-Sasl: arinc.unal@arinc9.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240313_080505_372670_E87F506F X-CRM114-Status: GOOD ( 26.44 ) X-BeenThere: linux-mediatek@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-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On 13.03.2024 16:13, Justin Swartz wrote: > On 2024-03-13 14:06, Arınç ÜNAL wrote: >> On 13.03.2024 14:52, Justin Swartz wrote: >>> >>> On 2024-03-13 10:59, Arınç ÜNAL wrote: >>>> This ship has sailed anyway. Now the changes the first patch did must be >>>> reverted too. I will deal with this from now on, you can stop sending >>>> patches regarding this. >>> >>> At least if the first patch isn't reverted, the approach used is >>> less likely to result in the problem occuring, IMHO. >> >> I disagree that the previous approach is less likely to result in the >> problem occurring. If you don't like the delay amount we agreed on, feel >> free to express a higher amount. > > I created and tested a patch to entertain your input about what you > thought could be a suitable hold period to address the problem, and it > appeared to work. The criteria being that the crystal frequency selection > was correct over 20 tests. > > So if only the reset hold period is going to change, I'm good with what > you had suggested: 5000 - 5100 usec. > > Ultimately the selection of this period should be guided by the timing > information provided in a datasheet or design guide from the manufacturer. That's a good point, I agree. > > If you, or anyone else, has such a document that provides this information > and is able to confirm or deny speculation about any/all timing periods > related to reset, please do so. These are the documents I use to program this switch family. I did not stumble upon a page going over this. MT7621 Giga Switch Programming Guide v0.3: https://github.com/vschagen/documents/blob/main/MT7621_ProgrammingGuide_GSW_v0_3.pdf MT7531 switch chip datasheet: https://wiki.banana-pi.org/Banana_Pi_BPI-R64#Documents > > >> I also disagree on introducing a solution that is in addition to another >> solution, both of which fix the same problem. > > I'm not sure I understand why you say that. These patches were intended > to be applied exclusively, or in other words: in isolation - not together. > > Although if they were applied together, it wouldn't really matter. > > For the record, I've only continued to keep this thread alive in the > hope that some solution to this problem will make it into mainline > eventually. > > I don't care if it was my original patch, the subsequent patch, or a > later patch provided by you or someone else. :) I think you've missed that your patch is already applied. And it won't be reverted for reasons explained by Paolo in this mail thread. https://git.kernel.org/netdev/net-next/c/2920dd92b980 So if your patch here were to be applied too, the final mt7530.c would have the LEDs disabled AND before reset deassertion delay increased. Arınç