From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us.padl.com (us.padl.com [216.154.215.154]) (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 735D640D594; Fri, 19 Jun 2026 05:00:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.154.215.154 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781845237; cv=none; b=sucPGZqWfmnCcQLCeXFzzADuOXhAYoi5Vu80/sC19JNXrpO2zvUvi00d9VQMwQREUHPKiFwjo3wH3q/AdvQBvEpUvVsFoMiTIGZ34tO+5YXiVdVeXLtMYQ8rNL50rjp/4iVu+V5SCZ716PtN78MENWUKtLXBXlU6bHHagVMPlXY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781845237; c=relaxed/simple; bh=z6dcnm0uxiuL+DZETzXLFk13tFMAyag5TyyJMqV8I1c=; h=Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Message-Id:References:To; b=EkoE7+ij1HuWd0naqVxD4f8PZGcgNnyTw0serjZk97mei2rxgkE3Rx73YfKTt/7o3IZUbSoLUckvlySnm56aBVvcbV0/y8HQjdQihUOAMvLIXG26QECrPB8+tDuIWJA40wM0mpOF7p9VVP1KP2E4Pd/QQyd3WPJI7EYbEzAZMUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=padl.com; spf=pass smtp.mailfrom=padl.com; dkim=pass (2048-bit key) header.d=padl.com header.i=@padl.com header.b=N/erb+7H; arc=none smtp.client-ip=216.154.215.154 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=padl.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=padl.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=padl.com header.i=@padl.com header.b="N/erb+7H" Received: from smtpclient.apple (border.lukktone.com [139.130.100.52]) by us.padl.com (Postfix) with ESMTPSA id 495AA60212; Fri, 19 Jun 2026 01:00:25 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=padl.com; s=default; t=1781845228; bh=z6dcnm0uxiuL+DZETzXLFk13tFMAyag5TyyJMqV8I1c=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From; b=N/erb+7HWBbx2a0DoIC5Unhl8qYX9Ft43tmPG6EeeLrxIg2JPYxFYICNN6gSmAgby VY+nZxGztGVLpKyF7Bdq8poCzs3/DzZjhoLpmVDldHL/vy2Hy79wgIHn7m0+K9wamL 5PMJXzTqmfAr8/KE19/iPCMQLpPTlRPVy5/dCZxziS5kqD4vOy/ftAKkQ8fQYAQDWi Ach036NEf5wMxbOzCiWmexel6B0crDu/qCjSoPsZ2iJQCiQiyDvhzOjt7ZSTnUtEQn nSnLDUdJDxzuIobLp+V/VsxBhLOR5LxWzE5iFgGtyukVYt4HehGGjKGTu/DUzwp8sp wHWfuVAgpzDqA== Content-Type: text/plain; charset=utf-8 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3826.700.81\)) Subject: Re: [PATCH net-next 2/2] net: dsa: mv88e6xxx: add support for credit based shaper From: Luke Howard In-Reply-To: Date: Fri, 19 Jun 2026 15:00:12 +1000 Cc: cedric.jehasse@luminex.be, Andrew Lunn , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Russell King , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Mellauner , Kieran Tyrrell Content-Transfer-Encoding: quoted-printable Message-Id: References: <20260522-net-next-mv88e6xxx-cbs-v1-0-c87a8e6bcc0c@luminex.be> <20260522-net-next-mv88e6xxx-cbs-v1-2-c87a8e6bcc0c@luminex.be> <0FB1CAF0-D30C-4A24-A684-1D1DBEE52FA5@padl.com> To: Cedric Jehasse X-Mailer: Apple Mail (2.3826.700.81) > On 28 May 2026, at 7:19=E2=80=AFpm, Cedric Jehasse = wrote: >=20 > On Thu, May 28, 2026 at 1:52=E2=80=AFAM Luke Howard = wrote: >> Would also be good to add support for the 6341, which as 4 queues but = uses the same Qav multipliers as the 6390. > I'll have a look at the 6341 As an aside, the 6341 driver is buggy. It assumes the chip does not have = a dedicated ATU FID register because it has 256 databases. This is = incorrect and breaks VLAN-aware bridging. I will post a patch when the = merge window reopens. On the hardware side, the ATU hashing algorithm appears to easily = collide. This causes problems with things such as installing the = broadcast address into multiple FIDs, not to mention 802.1Q Dynamic = Reservation Entries. The only workaround is to use the =E2=80=98direct=E2=80= =99 algorithm which may have a performance impact (I am presuming it is = a linear search; the data sheet warns against using it). Luke=