From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758097Ab2CIQeH (ORCPT ); Fri, 9 Mar 2012 11:34:07 -0500 Received: from mail-iy0-f174.google.com ([209.85.210.174]:47995 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757946Ab2CIQeD convert rfc822-to-8bit (ORCPT ); Fri, 9 Mar 2012 11:34:03 -0500 MIME-Version: 1.0 In-Reply-To: <20120308184954.GA1275@kroah.com> References: <20120308184954.GA1275@kroah.com> Date: Fri, 9 Mar 2012 17:34:03 +0100 Message-ID: Subject: Re: [PATCH] Clear previous interrupts after fifo is disabled From: Linus Walleij To: Greg Kroah-Hartman Cc: Chanho Min , Russell King , Alan Cox , Shreshtha Kumar Sahu , "Kim, Jong-Sung" , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 8, 2012 at 7:49 PM, Greg Kroah-Hartman wrote: > On Mon, Feb 27, 2012 at 06:30:20PM +0900, Chanho Min wrote: >> This is another workaroud of  'https://lkml.org/lkml/2012/1/17/104' >> with additional analysis.Bootloader can transfer control to kernel and >> there are some pending interrupts. In this case, RXFE of the flag >> register is set by clearing FEN(LCRH) even if rx data remains in the >> fifo. It seems that the fifo's status is initiailized. Interrupt >> handler can not get any data from data register because of the below >> break condtion. >> >> pl011_fifo_to_tty >>  while (max_count--) { >>    if (status & UART01x_FR_RXFE) >>       break; > > This patch never seemed to be agreed on, so I'm not taking it. > > Can someone, if this is still needed, and everyone agrees on how to > solve it, please send me the needed fix? To me it seems Russell's patch solves part of the problem, and Jong-Sung Kim's patch on top of that solves the entire problem, but Chanho need to come back and tell whether this is the case in practice. Yours, Linus Walleij From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Walleij Subject: Re: [PATCH] Clear previous interrupts after fifo is disabled Date: Fri, 9 Mar 2012 17:34:03 +0100 Message-ID: References: <20120308184954.GA1275@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-iy0-f174.google.com ([209.85.210.174]:58250 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757566Ab2CIQeD convert rfc822-to-8bit (ORCPT ); Fri, 9 Mar 2012 11:34:03 -0500 Received: by iagz16 with SMTP id z16so2457077iag.19 for ; Fri, 09 Mar 2012 08:34:03 -0800 (PST) In-Reply-To: <20120308184954.GA1275@kroah.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Greg Kroah-Hartman Cc: Chanho Min , Russell King , Alan Cox , Shreshtha Kumar Sahu , "Kim, Jong-Sung" , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org On Thu, Mar 8, 2012 at 7:49 PM, Greg Kroah-Hartman wrote: > On Mon, Feb 27, 2012 at 06:30:20PM +0900, Chanho Min wrote: >> This is another workaroud of =A0'https://lkml.org/lkml/2012/1/17/104= ' >> with additional analysis.Bootloader can transfer control to kernel a= nd >> there are some pending interrupts. In this case, RXFE of the flag >> register is set by clearing FEN(LCRH) even if rx data remains in the >> fifo. It seems that the fifo's status is initiailized. Interrupt >> handler can not get any data from data register because of the below >> break condtion. >> >> pl011_fifo_to_tty >> =A0while (max_count--) { >> =A0 =A0if (status & UART01x_FR_RXFE) >> =A0 =A0 =A0 break; > > This patch never seemed to be agreed on, so I'm not taking it. > > Can someone, if this is still needed, and everyone agrees on how to > solve it, please send me the needed fix? To me it seems Russell's patch solves part of the problem, and Jong-Sung Kim's patch on top of that solves the entire problem, but Chanho need to come back and tell whether this is the case in practice. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-serial"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html