From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BC93C2D0A3 for ; Tue, 3 Nov 2020 14:22:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0602B22280 for ; Tue, 3 Nov 2020 14:22:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604413352; bh=w+bDBq/x+hkhMlq/Y+Th6s2zei0WS0salk6dqD8g8Eg=; h=Subject:To:Cc:From:Date:List-ID:From; b=raftH4nLlz+0uZez5+i+Kcqwp8KSZtLrm9fLYwXamlDQgk8IEhwB5OoavXA1vnA4l qpz+R0yJyoaF5wgsTkVRWaZ27PMWxzSf79lNMQbAMUIYRXjf8j+7+wKTUwsp+yxqW9 F5tm6AknvIGHqJj+I7e7D9LmozffgsT5TTrgoB3w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729330AbgKCOW3 (ORCPT ); Tue, 3 Nov 2020 09:22:29 -0500 Received: from forward4-smtp.messagingengine.com ([66.111.4.238]:59317 "EHLO forward4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729263AbgKCOW3 (ORCPT ); Tue, 3 Nov 2020 09:22:29 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.nyi.internal (Postfix) with ESMTP id 1DA4919425D9; Tue, 3 Nov 2020 09:22:28 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Tue, 03 Nov 2020 09:22:28 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=H3ojhG el9HpFZI1GVP4kU/uXkyfh+x52fDCm950OnSg=; b=YUiNs+r6c2whlpPS999WLc HPcZWt09r69LvMgBJqeVJN1sC80LnZgxZw6gkNMJU/VTMoWvnZbl8TFp91ZSmIOv U/KTIDnl3feqXfEnIev52Cw32JFAgyjPb6jxsSuIP+RcZxMwwPxPqrDnks0yJDmx 7/1W4f6S4b4yKjCshc9qCb2SsPJsj5dlgs8Cpf+Zj8LcGomtIIz1XuNLS9zSULor uPvBda/StnENZ8q1EKA1l7onGMzbGEU1gxsQJ5buorfQ9mlhN4WhMdGIEk+js+hx 8lDav4YvK9ovI1qZysmVqHDmj0ESPLfW+UcxjqAgFvrsEKs5zTVQ2llGSSU0FSmw == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedruddtfedgieduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucgfrhhlucfvnfffucdluddtmdenucfjughrpefuvf fhfffkgggtgfesthekredttddtjeenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihf ohhunhgurghtihhonhdrohhrgheqnecuggftrfgrthhtvghrnhepkeejgffftefgveegge ehudfgleehkedthedtiefhieelieetveejvdfgvdeljeelnecuffhomhgrihhnpehkvghr nhgvlhdrohhrghenucfkphepkeefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiii gvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) by mail.messagingengine.com (Postfix) with ESMTPA id 326DA3280059; Tue, 3 Nov 2020 09:22:27 -0500 (EST) Subject: FAILED: patch "[PATCH] tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words," failed to apply to 5.4-stable tree To: vladimir.oltean@nxp.com, fugang.duan@nxp.com, gregkh@linuxfoundation.org, michael@walle.cc, stable@vger.kernel.org Cc: From: Date: Tue, 03 Nov 2020 15:23:20 +0100 Message-ID: <160441340011200@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From c97f2a6fb3dfbfbbc88edc8ea62ef2b944e18849 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Fri, 23 Oct 2020 04:34:29 +0300 Subject: [PATCH] tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Prior to the commit that this one fixes, the FIFO size was derived from the read-only register LPUARTx_FIFO[TXFIFOSIZE] using the following formula: TX FIFO size = 2 ^ (LPUARTx_FIFO[TXFIFOSIZE] - 1) The documentation for LS1021A is a mess. Under chapter 26.1.3 LS1021A LPUART module special consideration, it mentions TXFIFO_SZ and RXFIFO_SZ being equal to 4, and in the register description for LPUARTx_FIFO, it shows the out-of-reset value of TXFIFOSIZE and RXFIFOSIZE fields as "011", even though these registers read as "101" in reality. And when LPUART on LS1021A was working, the "101" value did correspond to "16 datawords", by applying the formula above, even though the documentation is wrong again (!!!!) and says that "101" means 64 datawords (hint: it doesn't). So the "new" formula created by commit f77ebb241ce0 has all the premises of being wrong for LS1021A, because it relied only on false data and no actual experimentation. Interestingly, in commit c2f448cff22a ("tty: serial: fsl_lpuart: add LS1028A support"), Michael Walle applied a workaround to this by manually setting the FIFO widths for LS1028A. It looks like the same values are used by LS1021A as well, in fact. When the driver thinks that it has a deeper FIFO than it really has, getty (user space) output gets truncated. Many thanks to Michael for pointing out where to look. Fixes: f77ebb241ce0 ("tty: serial: fsl_lpuart: correct the FIFO depth size") Suggested-by: Michael Walle Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20201023013429.3551026-1-vladimir.oltean@nxp.com Reviewed-by：Fugang Duan Cc: stable Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index ff4b88c637d0..bd047e1f9bea 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -314,9 +314,10 @@ MODULE_DEVICE_TABLE(of, lpuart_dt_ids); /* Forward declare this for the dma callbacks*/ static void lpuart_dma_tx_complete(void *arg); -static inline bool is_ls1028a_lpuart(struct lpuart_port *sport) +static inline bool is_layerscape_lpuart(struct lpuart_port *sport) { - return sport->devtype == LS1028A_LPUART; + return (sport->devtype == LS1021A_LPUART || + sport->devtype == LS1028A_LPUART); } static inline bool is_imx8qxp_lpuart(struct lpuart_port *sport) @@ -1701,11 +1702,11 @@ static int lpuart32_startup(struct uart_port *port) UARTFIFO_FIFOSIZE_MASK); /* - * The LS1028A has a fixed length of 16 words. Although it supports the - * RX/TXSIZE fields their encoding is different. Eg the reference manual - * states 0b101 is 16 words. + * The LS1021A and LS1028A have a fixed FIFO depth of 16 words. + * Although they support the RX/TXSIZE fields, their encoding is + * different. Eg the reference manual states 0b101 is 16 words. */ - if (is_ls1028a_lpuart(sport)) { + if (is_layerscape_lpuart(sport)) { sport->rxfifo_size = 16; sport->txfifo_size = 16; sport->port.fifosize = sport->txfifo_size;