From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9CADC471CF7; Wed, 23 Sep 2026 08:55:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790153721; cv=none; b=MkiMSqUW+/CuJ6RyfeFsR/YxHqe1YGAePZsxdlh4XPIvtEP8061OlLKBe57yRfJxgnU9nY5l0w8O64ZrIcbIRk/u9vJlzRu0F4sxDy3UVrBCmZTYxtUz+t3SriJp9DEqX2dD6UWA9UR4bNoV76npGV2B6oh7GmVnVpaj3j/MiGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790153721; c=relaxed/simple; bh=xE2IWCqMbPk5DBRIkHHAxIcJ03Qg45uYvB8gQsrMlsk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=snbBjI2neiY2ih3979dRlsfgY4Xaw3r3YjqGrwg0I91mC1chdeG5xYgSlOdC4IyMNpEGjPoDzcb6FoI0QvypRwDwkMZa0bGwOZ9I32obpJ8n8WkJ7jL7ZjzAN0AfyCendhSsgnZDjm+hjSMEJf/C/pp1IXKo75tGM9RAZ9qMiiA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iACzQIDD; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iACzQIDD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DC871F00898; Wed, 23 Sep 2026 08:55:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790153719; bh=80DZGmjDiR4Bg9Mnkz01B8NPJILVq5/IaueQvHOQ1e4=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=iACzQIDDqwQYRnvhG9KkuG0heW/4q3SDDtbBW6U3CqrXRI3/mCeelAApaskR6VBPB NUoief6+g5RW67Z/DNil33B6jzZeazIQLQFCp+7B7DOJ3iebE61O7rUWemyLYeQxNZ L1xtANiGEvJBwnBtbPAXK9mlB8UasThAaT/3P9NtAob05M+vAZ86tlj2GAwlYP0kQt T38Z8l3XATqB4k3TCFixC+Tm8BR5wxbk+dqu6KHoHr8fxF+Anu2dcLeHsEaJGEwT/t l3M3eOkCqwCqeHsib1ylNFEfeKru04l+VfM39z1IERrQa3lpYZsUYBzoMHMDun6JBP qHVAV2WRfkpTQ== Date: Wed, 23 Sep 2026 09:54:42 +0100 From: Simon Horman To: Daniel Machon Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Horatiu Vultur , Steen Hegelund , UNGLinuxDriver@microchip.com, Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Herve Codina , Arnd Bergmann , Greg Kroah-Hartman , Mohsin Bashir , Richard Cochran , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH net-next v7 04/14] net: lan966x: add FDMA LLP register write helper Message-ID: <20260923085211.GM13925@horms.kernel.org> References: <20260918-lan966x-pci-fdma-v7-0-0ecc179c8a2c@microchip.com> <20260918-lan966x-pci-fdma-v7-4-0ecc179c8a2c@microchip.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260918-lan966x-pci-fdma-v7-4-0ecc179c8a2c@microchip.com> On Fri, Sep 18, 2026 at 01:33:56PM +0200, Daniel Machon wrote: > The FDMA Link List Pointer (LLP) register points to the first DCB in the > chain and must be written before the channel is activated. This tells > the FDMA engine where to begin DMA transfers. > > Move the LLP register writes from the channel start/activate functions > into the allocation functions and introduce a shared > lan966x_fdma_llp_configure() helper. This is needed because the upcoming > PCIe FDMA path writes ATU-translated addresses to the LLP registers > instead of DMA addresses. Keeping the writes in the shared > start/activate path would overwrite these translated addresses. > > Tested-by: Herve Codina > Signed-off-by: Daniel Machon Reviewed-by: Simon Horman