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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50DB4C3DA78 for ; Tue, 17 Jan 2023 13:30:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230391AbjAQNaf (ORCPT ); Tue, 17 Jan 2023 08:30:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32836 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230222AbjAQNab (ORCPT ); Tue, 17 Jan 2023 08:30:31 -0500 Received: from mail-ej1-x62e.google.com (mail-ej1-x62e.google.com [IPv6:2a00:1450:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A29BE34C2C for ; Tue, 17 Jan 2023 05:30:30 -0800 (PST) Received: by mail-ej1-x62e.google.com with SMTP id kt14so16462324ejc.3 for ; Tue, 17 Jan 2023 05:30:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:user-agent:message-id :in-reply-to:date:references:subject:cc:to:from:from:to:cc:subject :date:message-id:reply-to; bh=7PtDi568nvDZ7QnbHicw2+ReSJgi7Uak7xLuSiA0KqQ=; b=SBs0BfNwPz7megYdnthzbaZmwfnZU+4A37DMer3pNrTUX0/t00a0XT2WQsIHigUqC0 cBopAACIqOyMJwd0/lLBrR1FmEDnZge3o+ZdaBiNnpEXc/I4foOZxy4vBRBvSDIh/lr/ grAnf/ONS6A+Uz+aCiU+3alXcxo8uH0/IaRNkToq8SRaSTZiRD+rg85x9IaWax/AGexE TxjAQkvqYHBwuIfpZl8dMl3Hf61N64zY7qXXfnCOQr8As4d7P63wXX9Iy/AHgGw8tfA+ w6fhe12nwEfKUrrjAOLnfAShT1jOqZV1kL4iq/TEF8x4zGWRiVzMUk6F/I31x9fJUxJN 91GA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:user-agent:message-id :in-reply-to:date:references:subject:cc:to:from:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=7PtDi568nvDZ7QnbHicw2+ReSJgi7Uak7xLuSiA0KqQ=; b=AIdqND2MebOr/syK/s4Toji17F6W19YgpPZAPnv/iY+C/4mMdfZf8uCqbD1QACIkbZ 56E9TCu4Gf3dqi4KrLBiuuIJ8zPfm1M+90CakDIqhikLP3QTzPML4h98WTY3b2vh12bx lPp4CgOVaZ621gitLINzAAwMVGzADPRCQkRJr5TZvUUcxiLWcMKzA4CO7NwkEgxuumsc Jhyv9Jii/yvHbkmjldUcV2VpI3Dms+/hLxqZCZ7Agzam/OkZladOjJhMD9gGXMyIUO3X vHoAvZ9PLniPvoWH3XJ+Zocu2BaG3/3W8p6K6UVyP7ybjX2rP5B07OaSgFQPbvZOM2Ot zRCg== X-Gm-Message-State: AFqh2kqN2ocO8eSmhpj8M+p3Zra6M7Pts+cXmEIZQK+kABiJFIMIJk+J Ypfsv9O7JIchSowN1nRibA+sFgNqN38= X-Google-Smtp-Source: AMrXdXtJVKsxuYXFr8ERmErZSCQZmV+juzZiDfpJQ4l4VRCGIDAoeXHAC6J5kO8YtAnqP3FtsgE61Q== X-Received: by 2002:a17:907:ca07:b0:86e:cb6c:4462 with SMTP id uk7-20020a170907ca0700b0086ecb6c4462mr2648376ejc.36.1673962229132; Tue, 17 Jan 2023 05:30:29 -0800 (PST) Received: from osv.localdomain ([89.175.180.246]) by smtp.gmail.com with ESMTPSA id e20-20020a170906249400b0084d4cb00f0csm10359629ejb.99.2023.01.17.05.30.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Jan 2023 05:30:28 -0800 (PST) From: Sergey Organov To: Ilpo =?utf-8?Q?J=C3=A4rvinen?= Cc: linux-serial@vger.kernel.org, Fabio Estevam , Greg Kroah-Hartman , Jiri Slaby , Richard Genoud , Sascha Hauer , Shawn Guo , Tim Harvey , Tomasz =?utf-8?Q?Mo=C5=84?= , linux-arm-kernel@lists.infradead.org, NXP Linux Team , Pengutronix Kernel Team Subject: Re: [PATCH 6/8] serial: imx: stop using USR2 in FIFO reading loop References: <87bko4e65y.fsf@osv.gnss.ru> <20230113184334.287130-1-sorganov@gmail.com> <20230113184334.287130-7-sorganov@gmail.com> <3c9ab74b-ff90-8371-75cd-1d2f7abb388d@linux.intel.com> Date: Tue, 17 Jan 2023 16:30:26 +0300 In-Reply-To: <3c9ab74b-ff90-8371-75cd-1d2f7abb388d@linux.intel.com> ("Ilpo =?utf-8?Q?J=C3=A4rvinen=22's?= message of "Mon, 16 Jan 2023 12:54:19 +0200 (EET)") Message-ID: <874jsp47bh.fsf@osv.gnss.ru> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Ilpo Järvinen writes: > On Fri, 13 Jan 2023, Sergey Organov wrote: > >> The chip provides all the needed bits in the URXD0 register that we read >> anyway for data, so get rid of reading USR2 and use only URXD0 bits >> instead. >> >> Signed-off-by: Sergey Organov >> --- >> drivers/tty/serial/imx.c | 18 ++++++------------ >> 1 file changed, 6 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c >> index c44a7293c013..be00362b8b67 100644 >> --- a/drivers/tty/serial/imx.c >> +++ b/drivers/tty/serial/imx.c >> @@ -892,27 +892,21 @@ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id) >> struct tty_port *port = &sport->port.state->port; >> u32 usr2; >> >> - usr2 = imx_uart_readl(sport, USR2); >> - >> /* If we received something, check for 0xff flood */ >> + usr2 = imx_uart_readl(sport, USR2); > > Please just place the read into the correct place in 2/8 rather than > moving it needlessly here again. Well, this I considered and rejected already, before publishing the patches. In 2/8 this read was an initialization for the entire FIFO reading loop, the value being re-used for flood check at the beginning as well, and with this patch it becomes just a local read for subsequent 2 lines of code that perform flood check, not used in the FIFO loop anymore, so I moved it in this patch to where it now belongs. Thanks, -- Sergey Organov 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E97CFC63797 for ; Tue, 17 Jan 2023 13:31:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:In-Reply-To: Date:References:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=+Ai1ub0ZM8bP+rY/siwXj1RK7lKq439hNtETBee5bRw=; b=dRwQEVO/CYreFm zhJAr+4xknWSx/DaUnNhSEl7PBzp0If9ORqLw0PbhSQslBGk4DI8WXhS03JPxrHfiSLu3G5oUNF55 yPOKsfhvGEnovZMoUWxnOjVlAv7DHKceiPLeQ/+dHrHXRMe6+nC+5puSxzvPdisC++AOzkl02+uzI zjP4HzdX/QTklJ3sR1duceqpemnCQ8S/5DPVIBJ/uQ5a3OXSDq3UpnOCstqhnPAlfWhrXMt6MHWpm iBbHH/LzTyd+FT1nXBxguxvSs/MOFXtqKcUd+cFYJPNOcsF9FK5NbN1iVWrunTXIyBgnneEXC4oIJ Vi54xQXunv7GnFN5dRSw==; 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Tue, 17 Jan 2023 05:30:28 -0800 (PST) From: Sergey Organov To: Ilpo =?utf-8?Q?J=C3=A4rvinen?= Cc: linux-serial@vger.kernel.org, Fabio Estevam , Greg Kroah-Hartman , Jiri Slaby , Richard Genoud , Sascha Hauer , Shawn Guo , Tim Harvey , Tomasz =?utf-8?Q?Mo=C5=84?= , linux-arm-kernel@lists.infradead.org, NXP Linux Team , Pengutronix Kernel Team Subject: Re: [PATCH 6/8] serial: imx: stop using USR2 in FIFO reading loop References: <87bko4e65y.fsf@osv.gnss.ru> <20230113184334.287130-1-sorganov@gmail.com> <20230113184334.287130-7-sorganov@gmail.com> <3c9ab74b-ff90-8371-75cd-1d2f7abb388d@linux.intel.com> Date: Tue, 17 Jan 2023 16:30:26 +0300 In-Reply-To: <3c9ab74b-ff90-8371-75cd-1d2f7abb388d@linux.intel.com> ("Ilpo =?utf-8?Q?J=C3=A4rvinen=22's?= message of "Mon, 16 Jan 2023 12:54:19 +0200 (EET)") Message-ID: <874jsp47bh.fsf@osv.gnss.ru> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230117_053033_035670_B7BA5F83 X-CRM114-Status: GOOD ( 18.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; 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