From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bird.elm.relay.mailchannels.net (bird.elm.relay.mailchannels.net [23.83.212.17]) (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 0BFE52BD001; Thu, 21 Aug 2025 21:21:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=23.83.212.17 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755811316; cv=pass; b=aaORIOpLJVEA+8B8f+l1Eguax2mXDzlPiHWtbIqIX7uUr8BD0wIaolgJPN3EhfigLKe2vQU5NIBVaRzSHzXITieA1NG6a8y2A41NlBTn/tqo2tD54EW4KsErJLhxdMIauW85TWKf1GVfdohWw8W1YKONeLihrfgcynLQp8aIH0U= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755811316; c=relaxed/simple; bh=gHc9N+sPNmbFdoVvlcXaXBnEUwSsL2C2pPfbjITtm2c=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=T24ZERiKtkukb2gip27u04p3LUQ2LzdbRX0C7Q7gHbl6my40KWs8SMPfIl1Qe3ffqIclOMSQzuc2POlhxgQ5Zybfc171Mpr/qb0aUFeRICrvAFE5BlSU/y+k/ewng1EPNnhJXrQ48gD2LoLe0isoUAuS8XhPYYpoiFODy4IS5BA= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=landley.net; spf=pass smtp.mailfrom=landley.net; dkim=pass (2048-bit key) header.d=landley.net header.i=@landley.net header.b=E7Ze60CN; arc=pass smtp.client-ip=23.83.212.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=landley.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=landley.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=landley.net header.i=@landley.net header.b="E7Ze60CN" X-Sender-Id: dreamhost|x-authsender|rob@landley.net Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id 67DB02C60D5; Thu, 21 Aug 2025 21:02:47 +0000 (UTC) Received: from pdx1-sub0-mail-a254.dreamhost.com (trex-blue-3.trex.outbound.svc.cluster.local [100.96.37.67]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id BB8372C6073; Thu, 21 Aug 2025 21:02:44 +0000 (UTC) ARC-Seal: i=1; s=arc-2022; d=mailchannels.net; t=1755810165; a=rsa-sha256; cv=none; b=VA395R/iBN/iOB+2AT3Sx/h1V57sN4gvPNEF/dlZq+Ge5opPfCJ/TpPnVatyDp0CHNJxEv tfDOgcPj/9I3SSVqRyD5TEldt/tqv/xweW+60BgBStohBbFv8e2ynhrglN2nyyxh25jZQA YORnb92Kh16oV1zpUf9tESKgdmeBarvhIeE7vF0+64eZYgtrrOlVucRk0kDNPxv7OQ5qY/ E2N1+scnJbeXWvTnXGmf8uS0oFkgbmIM+zJq5T0ul1As2+W1OWWVvNCUD+YIrVnck8t/2A ji//1hdJ9dZfNDYeeIgIAVsb/CjjUaJAfb6JHpd7XAcTnKIglfss8ZWkvQuNWg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=mailchannels.net; s=arc-2022; t=1755810165; 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:dkim-signature; bh=PiRdnVkb3Mdck8rf90p7+DnOfB9A+JduUXfai72Z7+4=; b=fvPcQG0GmaTFX0s1SvnPmsgzy7jrpdnnof5z+FJUBRcZNz6Yrb7EjpplCBztg5XKo8l85X vHXX5ehr9qCvBYjGuVtmUvNX7211fZM0R9Xql2poMvPoFXHnoBmEFYsyNj4CC5rM9SmwHO EAPh/w93JrVjFX3ybeA5SbFS+CvE6mYStAXAMcPUXA2p3YmsqIRTR+lWEtDtz6xxqipg7a wI/lpLAQAIurkhZwCy7PSEzAmul2gk48lwVbObDJY/IKmMwgd9RSptaiYI45tUTfv3K7ml HcRlx8kRl3opZw0WLx0xmQEJVlTb7vOavtegGw4yurw/8Zt+PJG4G0s6aM2eNg== ARC-Authentication-Results: i=1; rspamd-b597879cf-ngsbq; auth=pass smtp.auth=dreamhost smtp.mailfrom=rob@landley.net X-Sender-Id: dreamhost|x-authsender|rob@landley.net X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|rob@landley.net X-MailChannels-Auth-Id: dreamhost X-Macabre-Bubble: 2f8dd21033f8e097_1755810167283_2720825162 X-MC-Loop-Signature: 1755810167283:381200934 X-MC-Ingress-Time: 1755810167283 Received: from pdx1-sub0-mail-a254.dreamhost.com (pop.dreamhost.com [64.90.62.162]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384) by 100.96.37.67 (trex/7.1.3); Thu, 21 Aug 2025 21:02:47 +0000 Received: from [IPV6:2607:fb90:faae:51e1:d9d4:2e42:ae75:9827] (unknown [172.58.14.113]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: rob@landley.net) by pdx1-sub0-mail-a254.dreamhost.com (Postfix) with ESMTPSA id 4c7G431Sm7zDF; Thu, 21 Aug 2025 14:02:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=landley.net; s=dreamhost; t=1755810164; bh=PiRdnVkb3Mdck8rf90p7+DnOfB9A+JduUXfai72Z7+4=; h=Date:Subject:To:Cc:From:Content-Type:Content-Transfer-Encoding; b=E7Ze60CNKAiVA+WD8T4gncR5kdArdw1idFuny3yPyKtIHpxERaG5Sb3tizBAEbBL/ 1rZpQo1GhUTePym7uXRlMqKbqQScRPDFlva0DiRf+aR0LSjS/M+i/0OSjzvlYfTtCd IgsnjyNyyunyCtWVkBI/altwWbggCNtHJGZ7XJ3zZhXH203GZsTE7otLwmIRNL/uUV Fjdx1AxvsaHevwhNKe1sIfhj+tUt6JSudtond1NWpomo1JJ7C5lGodn70E5f4LSu22 96C1BYubVxQ4CfoUOIKdH3ZsHxphuqfLytr7+LmMt956XvMF7DNvFXe8gaUzBPpzRP pM+ZgqBhRFNkw== Message-ID: <4df745a6-2997-4eee-87b1-0c77ff46cfdd@landley.net> Date: Thu, 21 Aug 2025 16:02:41 -0500 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/3] dt-bindings: net: Add support for J-Core EMAC To: Rob Herring , "D. Jeff Dionne" Cc: Krzysztof Kozlowski , Geert Uytterhoeven , Artur Rojek , John Paul Adrian Glaubitz , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Krzysztof Kozlowski , Conor Dooley , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250815194806.1202589-3-contact@artur-rojek.eu> <26699eb1-26e8-4676-a7bc-623a1f770149@kernel.org> <295AB115-C189-430E-B361-4A892D7528C9@coresemi.io> <0784109c-bb3e-4c4e-a516-d9e11685f9fb@kernel.org> <20250820213959.GA1242641-robh@kernel.org> Content-Language: en-US From: Rob Landley In-Reply-To: <20250820213959.GA1242641-robh@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 8/20/25 16:39, Rob Herring wrote: > On Mon, Aug 18, 2025 at 10:55:51PM +0900, D. Jeff Dionne wrote: >> J-Core SoCs are assembled with an SoC generator tool from standard >> components. An SoC has a ROM from soc_gen with a Device Tree binary >> included. Therefore, J-Core SoC devices are designed to ‘just work’ >> with linux, but this means the DT entires are generic, slightly >> different than standard device tree practice. > > Yes. Though doesn't the SoC generator evolve/change? New features in the > IP blocks, bug fixes, etc. Soft IP for FPGAs is similar I think. The j-core guys almost never change the hardware interface on a deployed I/O device: when the existing interface is too limiting they do a new design with a different interface. (You'll notice in the github soc_top, components/ has ddr and ddr2, and components/misc has aic and aic2 from when the interrupt controller changed, for example. Those aren't version numbers, those are rewrites.) Outputting a different constellation of devices/busses from the SOC generator is more akin to running "make menuconfig". There isn't an ancestor/descendant relationship there, it's a generator working from a configuration to instantiate and connect existing components. > There > we typically just require the versioning schema be documented and > correlate to the IP versions (vs. made up v1, v2, v3). There hasn't been a new version of the 100baseT specification recently. The same chunk of bitstream is still driving the same PHY chips on the boards (or compatible, long out of patent) via the same small parallel bus at 50mhz. The engineers are no more interested in changing the kernel side interface than they are in changing the PHY side interface. > This is all pretty niche I think, so I'm not too concerned about what > you do here. Eh, not that niche. Just hardware development culture rather than software development culture. What's the model number on your microwave? If you need to replace it, how many versions will you advance? Chip model numbers tend to be assigned by marketing well after the fact, and don't necessarily have a linear relationship even for the big boys making central components other people build entire systems around: https://en.wikipedia.org/wiki/List_of_Qualcomm_Snapdragon_systems_on_chips The Pentium II's development name was Kalmath, Pentium III was Katmai, then Pentium 4 was a space heater and everybody backed up and switched to "Pentium M" (which was MEANT to be a mobile chip but was instead a "not stupid" chip) and then they did "Core"... And then "Core 2" and "Core Duo" were different things and "Core 2 Duo" was both of those things, and then they had i3 and i5 and i7 but they all came out at the same time... Jeep produced a "Cherokee" for 50 years and expected the user to step from a 1973 model to a 2023 model and be able to drive it the same (modulo major flag day changes like stick shift or leaded gasoline) with zero learning curve. Hardware developers of today go "here's an sd card, it goes click-click into your device and it just works, the only numbers you really need to know are price and capacity" (modulo microsd, but they still provide adapter sleds). Software developers think that "DOS 2.0" and "DOS 3.0" or "Windows 3.0" and "Windows 3.1" being profoundly different and largely incompatible is just normal, and track that stuff minutely. Different culture. Rob