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=1793913552; b=KwmAQAYwR3A2fvARMdrwiO62TkoJ13jkIYmBElRitEtmj7+ZTYjl26pvDvkWsFS0rkPi PHQvX9u24lyC5cRuKcMm/uU+vDmfRi0b7x7DZNM8MJ+wyjnF5v2j1a2aKSJ3M7/OQwMO0 /dR63cLVTtq5DyJ/RFFpb11p1GpInT+mxGVERR2W0D9uWLfxi2GrRsiZUwZW4blGCp4f7 kUHOWszHvTwWQxF7qv5OiLYpN7MnuhKVxQkh4ZdU5JmIpMyla3u/S7dJGR2QCZoMNeskX QDORuW/Klolacbgup4CZPoxGAjY6j8gCOKpTIOQ46+rosNro6NY1FXPDM7A7h29wLZQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793913552; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=Zj/uF/57kyYI1OIivex3W9Rx8gOrgw4ZoUg5xuhpknI=; b=lg6zmSJjKVQB8zLUhLnbKahjjB6z2xNDHTSTx2lA1qLHXgevR++22IzTUKAZlGC2Qt6c Bdt2gd6dPnr8ciEGImMape2VdVlZEPowDmbK4qLVFkHFeVrFs8NCSByoC6sFhPbHTauG8 ZSywfouZrjTwx4rvxqCN8tjHtQUoUfSh4aU7VYlg76/fbzQJG/fkKqMeyCVrEmgYxb+lX BOGEYox6K48jLxqYhis34bwIgpHX/TXjaA1r296QfzJR+ax0EWifRlnDVCg0Jw8PPNjUr mM2EfQnlGi3hHHHaHk3cf33nMeLCB2+XhsgWFNKcw6o1jVzHhXwbMRPaEY3Xc+pSLAg== 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=oTrTtymo; 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 2CAEF606A32F for ; Thu, 5 Nov 2026 21:19:11 +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=oTrTtymo Received: by smtp.kernel.org (Postfix) with ESMTPSA id A31781F008A7; Thu, 5 Nov 2026 21:19:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793913551; bh=Zj/uF/57kyYI1OIivex3W9Rx8gOrgw4ZoUg5xuhpknI=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=oTrTtymoRon6q2evizRWuaF5Ljxn8Qb2dlqIdild1ByBv3vMxFOmINNEQolIyvpMH bs4SssZm2IkrVCCzE4s7bit3CNHiI1Sd1DQmqhC9LFI6KOLV5DniPxHu6q/kt5Gj3H qOct72eysNkymaJekLI8AA6ilBd/BDFIIfDaq4fjFuO7Ead9VwRQOQOVFeZ6hktOF8 XWo/lZYfLMLXt1R5oYoFlHbMXpTbUyF7gZBF08VpR7GYaOPmM1idgb+BW41p7xemqZ +GzKkwfkQP+bRCCORob4R71KhFeTEoRW+O18JIToo2rP76t4FOLMDs8Nz5MeK02X/J hDIVDYL+P5PXQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v8 06/11] serial: 8250_dw: derive RX trigger thresholds from the FIFO depth Reply-To: sashiko-reviews@lists.linux.dev To: "James Hilliard" Cc: linux-serial@vger.kernel.org In-Reply-To: <20261105-submit-h616-uart-fifo-v1-v8-6-14024d2b184b@gmail.com> References: <20261105-submit-h616-uart-fifo-v1-v8-0-14024d2b184b@gmail.com> <20261105-submit-h616-uart-fifo-v1-v8-6-14024d2b184b@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 05 Nov 2026 21:19:11 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > DW_apb_uart uses receive thresholds of one byte, one quarter full, > one half full and two bytes below full. The generic 16550A table describes > these encodings only for a 16-byte FIFO. For example, the half-full setti= ng > on a 64-byte DW FIFO is reported as eight bytes instead of 32, and a sysfs > request for 32 bytes selects the 62-byte encoding. >=20 > Build a per-port threshold table from the discovered FIFO depth in dwlib > and install receive-trigger callbacks for CPR-described FIFOs, including > LPSS ports. Keep the setup helper available to integrations which obtain > the depth without probing the optional DW registers. Validate that each > threshold is positive and representable before constructing the table. >=20 > Serialize FCR updates with termios and the port lock, acquire a runtime PM > reference before accessing the device, and propagate resume errors without > changing the shadow or hardware. Update only the trigger field so changing > the threshold preserves the FIFO contents. >=20 > The FCR mapping is documented in the DW_apb_uart databook, section 6, > FIFO Control Register. The existing default FCR encoding is unchanged. >=20 > Signed-off-by: James Hilliard Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261105-submit-h61= 6-uart-fifo-v1-v8-0-14024d2b184b@gmail.com?part=3D6