From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 C8C341AF0B3; Mon, 2 Dec 2024 16:41:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733157669; cv=none; b=ZdjzbRCCg1oUnvgSbIlJRH/DfqRsGmQHu4nCnb0nx7BsJs7p0n1BON8hd917KzrNqzt4xkaSUrtBf0qV1m+Oc87Og0Bo4UXneyxfi/2JerWmT3u5T7ZO80TglhjM07VJpzemYSeO+nnbSftPnMAxrLm75GV6r4Tj3dffKiS+doE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733157669; c=relaxed/simple; bh=leCKbxXrI8wOLZxFyRTuo9pW3OvHH7MOuarDkdbV/4U=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=nHhXOrfPwwH+wnYtpOquybM168uTfyxXS4VhwlpDQ3EwNznAnmq4UUA+DH88wXufQJSwP2bYviThMLAAIxfzniyn65R3Ka9fvoj4QQu+3+p4yA54IWuivIpzh5jgZO2wLvwJ/9kf+mp/wQifdO45f8yRBdo5/vUlTKoxQ+yWG6g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=XkUZn/kB; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=uoWNt32n; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="XkUZn/kB"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="uoWNt32n" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1733157664; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=leCKbxXrI8wOLZxFyRTuo9pW3OvHH7MOuarDkdbV/4U=; b=XkUZn/kByETtNzQabzyrF/RDaWznNj2eeuVVCN13PO5XhhZHnDaeUPkjrsRz6HbNKEeN3u M5dyzHYUfMh8Dgu+GweshmtUmGs0MdD8sbzIOWsYC6VD7qhOjv8hILe4Q/BchK9y5wdD6/ bAoa9EQFX+O3s3W2KEVxaEav3jfPrIShQfoOuyyQIbTGZGR0I7eHECd/0rRg0lNLYiYcFQ Ks527QjS5c1VJj+N0WJAtmW3TqJ0/TA9h59uAwaY1XYHM/3FnWbFFZmbyyklujJDE/a3t4 IkPXJBMdRxc4eLlPfiXNosBlVlhTDEtRNvVYqKznZNj8boFr5NC3gz6MvViGMg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1733157664; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=leCKbxXrI8wOLZxFyRTuo9pW3OvHH7MOuarDkdbV/4U=; b=uoWNt32n96u7wwzMS/SKGXY8QsrRXaB5EMsFdLAxfmeA0yzQmXNMYWhVQ5eeF6wmV9CY+I 11GaNejeX65xpaDg== To: Jiri Slaby , "Maciej W. Rozycki" Cc: Greg Kroah-Hartman , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , Esben Haabendal , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Andy Shevchenko , Rengarajan S , Jeff Johnson , Serge Semin , Lino Sanfilippo , Wander Lairson Costa Subject: Re: [PATCH tty-next v3 1/6] serial: 8250: Adjust the timeout for FIFO mode In-Reply-To: <848cbe1c-d84d-4377-8709-bb98d1d83146@kernel.org> References: <20241025105728.602310-1-john.ogness@linutronix.de> <20241025105728.602310-2-john.ogness@linutronix.de> <837a7ecd-be29-4865-9543-cb6f7e7e46e7@kernel.org> <2fab2ef8-d0d6-4b94-90b6-7c16641a2f68@kernel.org> <84ldxzccjl.fsf@jogness.linutronix.de> <848cbe1c-d84d-4377-8709-bb98d1d83146@kernel.org> Date: Mon, 02 Dec 2024 17:47:03 +0106 Message-ID: <841pyqavhc.fsf@jogness.linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On 2024-12-02, Jiri Slaby wrote: > I am still asking why do you want to wait for the TX machinery at the > *end* (for the last 64 B of the 640 B line) of transmission at all? It > occurs to me as wasted cycles. The printk-framework has always expected that when console->write() returns, the data has been flushed out of the hardware. I am guessing because it is easiest to avoid possible data loss, for example, due to suspending hardware. If you want me to change the current behavior, I can do that in a separate patch. I would like this patch to only be about fixing the FIFO timeout issue. John