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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE6AEC433EF for ; Sat, 16 Oct 2021 13:56:10 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 9311460698 for ; Sat, 16 Oct 2021 13:56:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9311460698 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org 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=JcmXgwWnYWwPLZvO8Peqk0TEdpqX7jlGfeTJv/JJAgw=; b=JH0WAGFgWwxVtR eC2F06CUBjXM9hbh74apgzim56YmOY9E+BG3FBtm7Qy4h553ZJuhujcnITMqE9p0KB8fcdvm27gF6 hpks23ml19hTd5i9TooF6vTwpF+u/kJZ2jmu/Zg59dqpuWj4SOgCp4mzkODga1zt+VsWg2cc3fsaL Vt+8LFpT1yL62BmJE8iR3ZrzPF1/u6hN/S0UI/DDsynUUe8orT/GOPgL3L0yqnN/K9z1pkX67AAHs z4lyr1rvtWXJx7Klzl+3ytilSdmdUOyaTXeuPgUk7o49/QlllGkBoD1h730crYqxX5RtCHA2SDCk9 DDsDiM6/qLiu+uSafh7Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mbk9M-00AhdC-Qd; Sat, 16 Oct 2021 13:55:00 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mbk9J-00Ahca-Eh for linux-arm-kernel@lists.infradead.org; Sat, 16 Oct 2021 13:54:58 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DB0B660698; Sat, 16 Oct 2021 13:54:56 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mbk9G-00HCTW-Ld; Sat, 16 Oct 2021 14:54:54 +0100 Date: Sat, 16 Oct 2021 14:54:54 +0100 Message-ID: <87a6j9ulap.wl-maz@kernel.org> From: Marc Zyngier To: James Morse Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, Will Deacon , Catalin Marinas Subject: Re: [RFC PATCH 0/7] arm64: mm: Prototype to allow drivers to request PBHA values In-Reply-To: <20211015161416.2196-1-james.morse@arm.com> References: <20211015161416.2196-1-james.morse@arm.com> 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 (x86_64-pc-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: james.morse@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, will@kernel.org, catalin.marinas@arm.com 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-20211016_065457_533004_6F7E3034 X-CRM114-Status: GOOD ( 18.54 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi James, On Fri, 15 Oct 2021 17:14:09 +0100, James Morse wrote: > > Hello! > > Do you have hardware that uses PBHA? If so, what does the SoC do in > response to which bits, and what workload needs that behaviour? > > This series is a start at trying to work out what linux needs to > support to makeuse of existing SoCs using PBHA. Thanks for starting this. I think one part that is missing here is the device side of things. How do these attributes get used by the SMMU, how do we convey them to the DMA layer, and what is the expected behaviour when we have SVA? Not having any guidance form the architecture means that we're walking on very thin ice... M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel