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 E60128664C for ; Tue, 5 Mar 2024 15:13:22 +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=1709651603; cv=none; b=pABxzTNzVV8djKdRQSHulaJckNVGQCoM9I8icnudwtNO9QI38pmjYENkLJinZSZ4KlXX/qnOYDeoWGN83nkx04/rwsJULCeu+Frgz/Yp5VOJZnxOj6DlmlFm6/vMlZES+ZLjzx/609IFn5aB8XBjlR3h78EJOCH/CoISGvpFwA4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709651603; c=relaxed/simple; bh=Aqaq9DkI0sA9vn3RaElwpqJ0iWqko0W3IVJIlsmJ8TQ=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lnSHS3OE93gG9PjryxhWOnJrQ0HDtynjQLcR72aAk02P65rhCB/m0XHqtMoDfN7Wz+nTtYsV/sbGginEVeELDhZDUdJuSvBI1GleirFaznG0wq03/H+jxxhZ15FTiMMY3YV8Re08R17icfhBvB0pHexOauu65T0JGkLO6DRlcGE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tnVeoA5l; 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="tnVeoA5l" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CA76C433F1; Tue, 5 Mar 2024 15:13:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709651602; bh=Aqaq9DkI0sA9vn3RaElwpqJ0iWqko0W3IVJIlsmJ8TQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=tnVeoA5l84SfAb6fiqv2iiBi5PQPbntwLAPqWvDXiocc7oo/rf+ZLusGTAih40Cn6 VMcZKdL5i6h7Jc5jHTkKIQgAI+fmM8qYhv/AYk2XNL+WYUeoSb6fBDnQcC26OcZc8V 3i5RDThWPlo2CyP5gsDeGkzoFkmbmnxd5XXM22yrcyrJAWXIQbnPqvTcijXVedPXL/ 0dH5ANigVNEymD+46fV6gO3VpCUPtoK/E1LMlTg3Szbkopq5BavFno/EO8LdbmJfkv VqEIOrdaTHWHsMTiNWaB2/QY7RV0P4URep26ba2YZ25bQ3q297xBs1vG2oDfNFaCSQ qF+vnTUQuoFBw== Date: Tue, 5 Mar 2024 07:13:21 -0800 From: Jakub Kicinski To: Doug Berger Cc: Florian Fainelli , Maarten Vanraes , netdev@vger.kernel.org, Broadcom internal kernel review list , Phil Elwell Subject: Re: [PATCH] net: bcmgenet: Reset RBUF on first open Message-ID: <20240305071321.4f522fe8@kernel.org> In-Reply-To: References: <20240224000025.2078580-1-maarten@rmail.be> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 26 Feb 2024 15:13:57 -0800 Doug Berger wrote: > I agree that the Linux driver expects the GENET core to be in a "quasi > power-on-reset state" and it seems likely that in both Maxime's case and > the one identified here that is not the case. It would appear that the > Raspberry Pi bootloader and/or "firmware" are likely not disabling the > GENET receiver after loading the kernel image and before invoking the > kernel. They may be disabling the DMA, but that is insufficient since > any received data would likely overflow the RBUF leaving it in a "bad" > state which this patch apparently improves. > > So it seems likely these issues are caused by improper > bootloader/firmware behavior. > > That said, I suppose it would be nice if the driver were more robust. > However, we both know how finicky the receive path of the GENET core can > be about its initialization. Therefore, I am unwilling to "bless" this > change for upstream without more due diligence on our side. The patch has minor formatting issues (using spaces to indent). Once you've gain sufficient confidence that it doesn't cause issues - please mend that and repost. -- pw-bot: cr