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 9EA9AC4332F for ; Tue, 22 Nov 2022 17:28:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Subject:Cc:To:From:Message-ID:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=4CwXptt7gxn44fzzukBjCdVXEgVAL+JI6fT4D8PYkUY=; b=GiHhjmUDtpprfj I8lcsXr7HGV0iuNTsKJMcNEAMu5Do6MsBxoXiAtxEvGQ0a/ZTWVjTojhomxxu6MqTnTVonLCm53T3 5FJRQPN2Vp42eg/FZQmRTU5P/sy2+CrjDhSDkInlq1nICXVcm1Cf3gaLrrrxdWOqH5hhoTWNYhZc4 hXVxAVrQTLg2xP4LZehyDXDjHZwuLNGI2kcFtjGeHycHSFGcaeR4zpVu/1Vves/vc9slV8k7IkVLQ 2TKSvV2kOACFXoPO74LLkqxZl0xfKhNpKOuogNBmQJd0PZz+yNjY3lQnC/hMRqBY6TaZXdFdizRu1 mFMA2gmqiN4+hSaHYFxg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oxX4P-00B3as-Ob; Tue, 22 Nov 2022 17:28:29 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oxX4N-00B3YN-0W for linux-riscv@lists.infradead.org; Tue, 22 Nov 2022 17:28:28 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A9786B81CF4; Tue, 22 Nov 2022 17:28:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53FBBC433C1; Tue, 22 Nov 2022 17:28:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1669138101; bh=bPGORzn/O+lk6aHPgo/zL2qYgbZzPpf9Wn0quTNAY3Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=knhLOPsIKyVoFTl5kAH4EdE983hWomqK6BYc1AVmzMlyiMs5jtoo45vIdA0aeqNjz 5//NlABsPxh6h4eMGj2709VOZQqBLfECd/gASvC3VJENWGaW6VvCGH+CIbHPE+x/jw URGVd0bwof88pR5PIoq2rcGhdw8bjQTNmA58hWj+lW0qLqeYihzKmmxcdvthRGxhYM cK+r/HR+Obi6P/sUz3q5QKNem9MyFb+gSjwFf3cFIj/A5nCdOshyUs/dOMSgXt6lo2 DdCBSo0cUrGU3p20A2OmSvfOEuT+x+gXDAB26tjqzcgrVYhm0viWpc12mAlOwaJiql hqYdaGxHVC8Nw== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1oxX4E-007vIc-W4; Tue, 22 Nov 2022 17:28:19 +0000 Date: Tue, 22 Nov 2022 17:28:18 +0000 Message-ID: <86o7syoq4t.wl-maz@kernel.org> From: Marc Zyngier To: Icenowy Zheng Cc: Thomas Gleixner , Palmer Dabbelt , Paul Walmsley , Samuel Holland , linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH] irqchip/sifive-plic: drop quirk for two-cell variant In-Reply-To: <20221121042026.419383-1-uwu@icenowy.me> References: <20221121042026.419383-1-uwu@icenowy.me> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: uwu@icenowy.me, tglx@linutronix.de, palmer@dabbelt.com, paul.walmsley@sifive.com, samuel@sholland.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221122_092827_246208_D13C3D5A X-CRM114-Status: GOOD ( 20.18 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Mon, 21 Nov 2022 04:20:26 +0000, Icenowy Zheng wrote: > > As the special handling of edge-triggered interrupts are defined in the > PLIC spec, we can assume it's not a quirk, but a feature of the PLIC > spec; thus making it a quirk and use quirk-based codepath is not so > necessary. It *is* necessary. > > Move to a #interrupt-cells-based practice which will allow both device > trees without interrupt flags and with interrupt flags work for all > compatible strings. No. You're tying together two unrelated concepts: - Edges get dropped in some implementations (and only some). You can argue that the architecture allows it, but I see it is an implementation bug. - The need for expressing additional information in the interrupt specifier is not necessarily related to the above. Other interrupt controllers use extra cells to encode the interrupt affinity, for example. I want these two things to be kept separate. Otherwise, once we get some fancy ACPI support for RISCV (no, please...), we'll have to redo the whole thing... > In addition, this addresses a stable version DT binding violation -- > Linux v5.19 comes with "thead,c900-plic" with #interrupt-cells defined to > be 1 instead of 2, this commit will allow DTs that complies to Linux > v5.19 binding work (although no such DT is devliered to the public now). *That* is what should get fixed. Thanks, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv