From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792677700; b=tXfLFQQ9wkmeADfKrO8PjW7AGZsugjdQu0R9+O/Iqrdmwa3I449+0tIs8QQkz427c/P7 KqZZBJVmfLhTsmzIs/ew9s/VjEh7jqLQfsEqGtnDqBvxC9qyjmGxLCOZgXiAS6wBxHKu6 9R+LtqSe1o8r+hLVIopmT4R8jDFalnapr0a88kualBB8KC26MlF4TXYvDwAD61oo+U6tw oj14E7tGJSMPPlGRApOPqv9S+2aU5XZl0mZXVQCrHEx2s/JOIxpyXL7QXuQ4n2+IfBXhi VggrENAKcr8uJ7bKMDJOVwx/az11rSAmeyrRb5Ju4JjCoM9YcWdSuddWyuOv6fQRjQw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792677700; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=5ZojtnmsIc3/F6yRUC+D32/HMvjsgQALAlW7R9xX2fo=; b=pWvEC4KK21LNO6Wi7Z40WjRPfnKVg69hGqS1YFHI8uPXvMUW4rBVw2EoLlFM+iR/qmIo 8lsRIQWYLaSxpRgnr52bA0iYXdzDDA/DUGSZ3JpXpJWyGzKNsoZW3d8X02QyJMVkA16TG uAsH8+jQ/MZZKnJ1BEYU36+yo5F6ESrMeLoFim6uoMk9HZcsf3WDZxR/CpjNzr3ZVo3mo v13GKgYnib3W3ZM6jRhOwa7kEpm4O0pHk4Lmx8iXir8/ZM+G16Nmv/7HtsfKTWxevkBs9 PQ3JXjdyrvnYevYRPuxD78caqHi3G94ZIauG8/afa+WNhqDDB5+SljSAXcnwsw3gzEg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="O/HS6Z6y"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77DCA606A31E; Thu, 22 Oct 2026 14:01:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=O/HS6Z6y Received: by smtp.kernel.org (Postfix) with ESMTPSA id D65D01F000C1; Thu, 22 Oct 2026 14:01:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792677700; bh=5ZojtnmsIc3/F6yRUC+D32/HMvjsgQALAlW7R9xX2fo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=O/HS6Z6yOiWqf7fg0SZopYIagYjHfvssuDMpBMP1zBjpLfFkmXF69avT6vj9Mn3MZ URCiHONgUaNvmyMAwTenU3WHsJeYE6yApsPsHMigA6BBeu/TKsdiDjcZWgtQec1WWB BsqJmPNVAuhkb7TrhBFWvnfAOhn1FLqLTY1zYZXx6/CMKhYn80mfFj5RTXP+sxXAyK mI9088pBA5dYPqJe202R1hmka1t8eFoOwrqTqeWlD1do9tvyudvBFIZu7TQO4y4M8q m9m6EEYtchqMvEtSiLVT5wPbyr43QQsQ1x+5Gwk/gfRfx2vjlihP3SwyR6LxN1E+Eb 7SFKbg04ESzoA== Date: Thu, 22 Oct 2026 09:01:39 -0500 From: Rob Herring To: Vishnu Santhosh Cc: Vinod Koul , Frank Li , Krzysztof Kozlowski , Conor Dooley , Andy Gross , Bjorn Andersson , linux-arm-msm@vger.kernel.org, dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Deepak Kumar Singh Subject: Re: [PATCH v3] dt-bindings: dma: qcom,bam-dma: Allow memory-region property Message-ID: <20261022140139.GA952798-robh@kernel.org> References: <20261021-qcom-bam-dma-vmid-ext-v3-1-299355e8dd3b@oss.qualcomm.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261021-qcom-bam-dma-vmid-ext-v3-1-299355e8dd3b@oss.qualcomm.com> On Wed, Oct 21, 2026 at 11:22:35AM +0530, Vishnu Santhosh wrote: > Some Qualcomm SoCs, such as Shikra, run the modem in a separate security > domain, preventing it from accessing BAM descriptor FIFOs allocated from > arbitrary host memory. > > Add an optional memory-region property to constrain DMA allocations made > by the BAM DMA controller to a restricted DMA pool. Access permissions > for the remote execution environment are managed separately. dma-ranges is normally how address restrictions for a device are defined. Why can't that be used here? Rob