From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4AB862D9EFB; Tue, 30 Dec 2025 02:13:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767060788; cv=none; b=uCddO2aysQTfOpnF9z0paoAioMj/pQwAYqMlIL/Ium9ylvlrUMLoiFdPJsqyuuPqYqaX+A/5erhkFc7mMLxYdcsJtGVCdKO96ruz4a30lu7eeVr9DiSZr3n2CV+P4Gb+uBRSwiIw0zsKtRvkXUgQwEdsizSvT2fVEL+KRbFYfUo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767060788; c=relaxed/simple; bh=ujZ1P5lBfgwx4tIvimvvLGd3ecXpSBouVkmJT85mccE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ICAmFzChP8Gex6OMll/L/+zZ6Thl3JbB0ZX1FnzGT6U6SLBUZzT+eXoak0x4zGdj5AsRibEmmJCq4cnhqilygC3/SMovvxxUUdgNSQfavE5EIAC7Pi9gc7glcMY24ZWsOxQYdSPBOL+sU++FNJyMmjzEmRadPZQkSZ5ex5kHue4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tO5bdLtO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tO5bdLtO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8767CC4CEF7; Tue, 30 Dec 2025 02:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767060787; bh=ujZ1P5lBfgwx4tIvimvvLGd3ecXpSBouVkmJT85mccE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tO5bdLtO41d5F00M9eL2DiNwnBmycH8RX0eeY8cU9C018ar4bwq3t03A7MoZfZzUz 9FBHnO+00LiF1B+K7zKr/Oz9AOJk4J1orJWhkDCBCs4ikFjOPDWMYyVFseD4Hq0/1y uH8a7PQsFR5ibtYPiQVz1zhYq27LxP8C7x5tjaJKQo80xY5c0owDKGqFxcxzAXhRRp HMlUD/RzwJMZssgwuBo4y4+DyYLMrFAFcbEGVA7ZtL+BNZP5s2Sn1qVi5WwE+XiNJy Jysl5qkbNDmh3ZSmjYd6t4gElEQTv9kPzZe/NkqZlAc1SN02Alkec98FX8b2vbQOgo zcoI/C3d6MY9w== Date: Mon, 29 Dec 2025 20:13:06 -0600 From: Rob Herring To: Alex Elder Cc: Guodong Xu , Krzysztof Kozlowski , Conor Dooley , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Yixun Lan , Daniel Lezcano , Thomas Gleixner , Samuel Holland , Anup Patel , Greg Kroah-Hartman , Jiri Slaby , Lubomir Rintel , Yangyu Chen , Paul Walmsley , Conor Dooley , Heinrich Schuchardt , Kevin Meng Zhang , Andrew Jones , devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, spacemit@lists.linux.dev, linux-serial@vger.kernel.org Subject: Re: [PATCH v2 11/13] dt-bindings: riscv: Add Supm extension description Message-ID: <20251230021306.GA3094273-robh@kernel.org> References: <20251222-k3-basic-dt-v2-0-3af3f3cd0f8a@riscstar.com> <20251222-k3-basic-dt-v2-11-3af3f3cd0f8a@riscstar.com> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Dec 26, 2025 at 03:28:47PM -0600, Alex Elder wrote: > On 12/22/25 7:04 AM, Guodong Xu wrote: > > Add description for the Supm extension. Supm indicates support for pointer > > masking in user mode. Supm is mandatory for RVA23S64. > > > > The Supm extension is ratified in commit d70011dde6c2 ("Update to ratified > > state") of riscv-j-extension. > > > > Supm depends on either Smnpm or Ssnpm, so add a schema check to enforce > > this dependency. > > I have the same general question on this, about whether it's really > necessary for the DT binding to enforce these requirements. The > RISC-V specifications are what truly defines their meaning, so I > don't really see why the DT framework should need to enforce them. > (That said, I'm sure there are other cases where DT enforces things > it shouldn't have to.) Does the specification have some way to check it? What happens if a DT is wrong? Are you going to require a DT update to make things right? Or the kernel has to work-around the error? Neither is great. So having this as a schema makes sense to prevent either scenario. > > And now, having looked at these added binding definitions (in patches > 07 through 11 in this series), I wonder what exactly is required for > them to be accepted. For the most part these seem to just be defining > how the extensions specified for RISC-V are to be expressed in > DT files. It seems to be a fairly straightforward copy from the > ratified specification(s) to the YAML format. > > Who need to sign off on it? Conor? Paul? DT maintainers? I generally leave this extension mess to Conor. Rob