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=1794235917; b=OzXkHT7WYSRfgHcIuZ/tf/JLFATEFl7S0WCXAdUshIAcDiQzAkYhbMAILBSRPHPON96+ 3gAlf3V+fnse2YprD5ivo2CxzxtHWqxoWHSxXScC4KSo8bhLr96DFQjVRJb7QsnXgZQNZ UmnEgIWzkMTTbnkrb6BmvWW2aMqexxssNazprEIzTa/KISUZn7Q0yGu2mbRb0JTNtIDTd TOAEZl383S62N2+NoenjsOrBja94Q4/zTibcgEsGWpFy7hHJHCaTTfaLeHHYyKpnuTKze GeY8XG55k8fLJLx96SBla0ONxMw9MrpUafSUpwxiIQ+9PwOcS3NhqY4nBiPs6/+nK7g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794235917; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=QVN3Q7FA2EALt28ulM5kE5A2x0Xe8k6YsLJ/Ap5Gs+0=; b=iP+k5IgJYO+9hmsxzcS1y8jXI2VACvp+BKYeB2FoKzmVdzL0M7iCygYgKiCW50PoQsI5 p2FuMW0om4YVzUEJX4/q0iq+gyD75EMCE5w8+D4jKknTBewihConUJgjAxN5/9fv2dWYX RBcjgSrFbcMSGkXRdVGx5prHCRtBNGxXk274JZS28efg/kGHOhnPIJMYoJUjN8o0owJJW B6wVpEiIiYr+tERqV3pE/eqVCEu8ce/VG6VBntMKTzKAazDg4YOWaZMVAuE40FC6jjHX+ udRFNZvQgoKPlEWuLGFmgXP+WuwgvYnsNqnbV28LnfW8zWBCi0e1cVNNg9/EfcCywHA== 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=hW6KFwfq; 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 6A6D0606EE80 for ; Mon, 9 Nov 2026 14:51:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=hW6KFwfq Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF91F1F008A5; Mon, 9 Nov 2026 14:51:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794235917; bh=QVN3Q7FA2EALt28ulM5kE5A2x0Xe8k6YsLJ/Ap5Gs+0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=hW6KFwfqxMT9Onm7lVlGqvAdiDxFjsySMby9DYZSOybv4A00vK3g+4zLwYLsqN8E8 i+Htk6/2/4wznHUxKE3cwDMrFcpxndMB1/sXRKKiDMornzKVeTfGzuW+yN7vOgBfHY P41C0i88ai/6KR08qJiFlx3gJcANjnKb1YHwTHd4Oko2EVIWzuwnux7IIRsjMVYCXf /YGu4tQ56jfqB7wIWnpy5tTgf6Q9xgW4dt4OnM3XjKYRDidCRTCqakvinUkkn7D742 v0US8DHy8SB+LP2DphzpMS/E+Kcwsx7U/DWPTtDPkGpd2gEv5GDchxdulQOcfdN2L/ 8WpA9jEyTyF/A== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 2/2] serial: 8250_dw: Select U6_16550A for 64-byte FIFO Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?S3J5xaF0b2YgxIxlcm7DvQ==?= Cc: linux-serial@vger.kernel.org In-Reply-To: <20261109-8250-select-u6-64bit-v1-2-04bc8332fa34@gmail.com> References: <20261109-8250-select-u6-64bit-v1-0-04bc8332fa34@gmail.com> <20261109-8250-select-u6-64bit-v1-2-04bc8332fa34@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 09 Nov 2026 14:51:54 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Kry=C5=A1tof =C4=8Cern=C3=BD >=20 > DesignWare 8250 ports that describe their FIFO in the CPR register are > always configured as PORT_16550A, regardless of the FIFO depth. On > UARTs with a 64-byte FIFO, such as those on the Rockchip RK3328, this > selects the 16-byte rxtrig_bytes table {1, 4, 8, 14}. The rx_trig_bytes > sysfs attribute then reports 8 bytes while the hardware triggers at 32, > and writes to it program the wrong trigger level. >=20 > Select PORT_U6_16550A when the CPR reports a 64-byte FIFO. Generic > autoconfig already assigns this type to a 16550A with a 64-byte FIFO, > and its rxtrig_bytes table matches the DesignWare FCR RT encoding. >=20 > The FIFO size, TX load size and capabilities are still taken from the > CPR, and the default FCR value is the same for both types, so the > hardware is programmed exactly as before. The port type reported to > userspace changes from 16550A to U6_16550A. >=20 > Co-developed-by: Miroslav Ondra > Signed-off-by: Miroslav Ondra > Signed-off-by: Kry=C5=A1tof =C4=8Cern=C3=BD Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261109-8250-selec= t-u6-64bit-v1-0-04bc8332fa34@gmail.com?part=3D2