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=1792429701; b=XYvamri7YzhjMI2OaFpW12oDHMOydfVQugXhmSCiHHv2Kb21c4ql5B6zkBsEdnhKAxwt 4npdp9i3KbMnOIGPbR9YNUeixT3weaWqnrHHlywdPEdmICHjktKFTB2XHEIrQ58E4NG2f pwTWlMjMexNRQeeifiGgVmeTmM1WgfN+t2kfstCSGRiYDIwhRez4PDp9XPYhb2HUAbyjO UzM+kUbFIabPexTi7mxJePyVqXO/C5A8XN0hAe7A/VF86XPQNZyE3R+bCfQSlnqgQ/Adl lw7I1JNoCheC99svrBu7SimgORP3IYP0LuiTFOb87xiWpliv4bcKwwy4KuLa8ZMnBYQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792429701; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=A8naO/tXKG3IPwGPGBMQH2rn/Ky0M+djBZjiGbXklEA=; b=NcXtZcJUYaXc4o3TN6WO7HRqf7Ou/etibztDvV4FWzMQ5ls0ZIqok9bX4rH+kjnQN+Rb j3ndJ63QzNLK9GTWZIQNy5SJVTvASuXHlbxAe+e/KZyYH/nQ/oTRB9W1ajYJgBVixAhbK HJIvc2e1M26s5sXuYCqJVp+QUrhrUaL0tHqKd0Lw4KJWWcbA8TB/Wiv8hrObTNlvZS6yh ZEKnEI1B0NWVQdcz1Ei1CvaBg5pbEDj40znXUmO2ECGLn5yXFBO0PzMpiavaBfDU4Crj+ ChZcLAnCAegjq0G+fplGvepqxs1JWb3H4yiSHK4Io6edLqr/qrg66X9974X33BavT3Q== 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=NbXvYxIT; 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) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41D33606A31C for ; Mon, 19 Oct 2026 17:08:21 +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=NbXvYxIT Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB76F1F000C4; Mon, 19 Oct 2026 17:08:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792429700; bh=A8naO/tXKG3IPwGPGBMQH2rn/Ky0M+djBZjiGbXklEA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=NbXvYxITPYai3qBXWnjDBVk8nD49tf58Ic/bMkf1UGr1xxEK0hofQ1t2tZa/sDT7K JpQaZhiTwn332Ky5KZBrs1SWxaL8mVDadprf05Km0Llk4C0ziKiRBeCYP+5fvnDqhb L+Uck42xrnxsTQ93vX/qWKo883q3s3Xf/iDntk/o5kl9xWMZDYX7FQJ/FardemQ0AI IZOw1peO0d+jw936VYmEgQt/z/AJdJ01StgpnywbBoZbBf4mwVecUr4IJVQKZAMgrF xdlakgZSM1w6EH6pP8er9tbQ6ZMaFmt6TlZwjhHDTjFdkHvnsJbXm7wM0kQlz8lj4I eGMClGHRtC36w== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 4/4] serial: sh-sci: Toggle TE when restoring SCSCR in console write on SCI Reply-To: sashiko-reviews@lists.linux.dev To: Biju Cc: linux-serial@vger.kernel.org In-Reply-To: <20261019170139.473808-5-biju.das.jz@bp.renesas.com> References: <20261019170139.473808-1-biju.das.jz@bp.renesas.com> <20261019170139.473808-5-biju.das.jz@bp.renesas.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 19 Oct 2026 17:08:20 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Au Dang >=20 > When SCI0 (PORT_SCI) is the system console on RZ/G2UL, the board can > hang at the serial console output stage during boot. >=20 > ftrace shows the following sequence: >=20 > 1. sci_transmit_chars() is draining the TX kfifo through TXI > interrupts with SCSCR=3D0xf0 (TE=3D1, TIE=3D1, RE=3D1, RIE=3D1). >=20 > 2. serial_console_write() runs in the middle of that drain. It saves > SCSCR=3D0xf0, switches to polling by writing SCSCR=3D0x30 (TE=3D1, TIE= =3D0) > and outputs the characters with sci_poll_put_char(). >=20 > 3. It then restores SCSCR=3D0xf0 in a single write. TE is 1 both before > [ ... ] > TIE is being re-enabled, so TXI fires and the interrupted drain > resumes. >=20 > Signed-off-by: Au Dang > Signed-off-by: Biju Das Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261019170139.4738= 08-1-biju.das.jz@bp.renesas.com?part=3D4