From owner-freebsd-embedded@FreeBSD.ORG Mon Oct 7 20:15:17 2013 Return-Path: Delivered-To: freebsd-embedded@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 714EF9EE; Mon, 7 Oct 2013 20:15:17 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-qe0-x22c.google.com (mail-qe0-x22c.google.com [IPv6:2607:f8b0:400d:c02::22c]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id F02642F5C; Mon, 7 Oct 2013 20:15:16 +0000 (UTC) Received: by mail-qe0-f44.google.com with SMTP id 6so2989873qeb.31 for ; Mon, 07 Oct 2013 13:15:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=GBi01RdvJa/jwavzBSnrAgiK0r5Pe0/Yd32ZEQ1tCaY=; b=EQ0J3ofsKVb1ZY3Ic6c+NjMShUYPzdNjIRcZCjac15iWxDdq9Jikldf+Ih0rJ3xJCX x07aPl+P6H8k3tcv2SGsFAIS+yF5PqOV6BuHe7YBmCYyJ2svUwNg8nt2zLRxRWgW95Mu AsKFvkawrDvx3UJ/qCpmEdNbeRQ++a5CSYhPH4ipC3KXuYE40Z9Gj0onnqcpjZpCZVts bJb5VvASZwtVhn5oUnIl8Cdio+KNy8rwDHoSwF+mULxy5jl9n7ourKYCEG9uQipR1Uvi YGGMK5qaTfJrVvjVUF068j9NxvsQfOIMxSjsPONb0+D8RvaMnb9kzEdvNxzkrKlF4AjA 1PMg== MIME-Version: 1.0 X-Received: by 10.224.157.14 with SMTP id z14mr5169015qaw.90.1381176916112; Mon, 07 Oct 2013 13:15:16 -0700 (PDT) Sender: adrian.chadd@gmail.com Received: by 10.224.207.66 with HTTP; Mon, 7 Oct 2013 13:15:16 -0700 (PDT) In-Reply-To: References: Date: Mon, 7 Oct 2013 13:15:16 -0700 X-Google-Sender-Auth: NNgCXYLGRSNjy6J5wKblc7oqS8I Message-ID: Subject: Re: Changes to UART ns8250 From: Adrian Chadd To: Zbigniew Bodek Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: "freebsd-arm@freebsd.org" , freebsd-current , "freebsd-embedded@freebsd.org" X-BeenThere: freebsd-embedded@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Dedicated and Embedded Systems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Oct 2013 20:15:17 -0000 Hi, You should add: * a loop counter, to break out after a while; * a DELAY(1) or something. -adrian On 7 October 2013 12:54, Zbigniew Bodek wrote: > Hello. > > I would like to present a patch for ns8250 serial that I would like to > commit in the near future (if there are no objections). > > The patch is fixing newest DesignWare UART with busy detection. > During frequency divisors configuration when UART is busy transferring or > receiving data, line control register manipulation will not take effect. > Therefore, we will not set divisor latch access bit and we will corrupt LCR > instead of configuring divisors. > It is necessary to wait until UART finishes all transfers to proceed with > the configuration. > > This was detected on Armada XP as UART fails on this issue 100/100 > attempts. > The patch was tested by kevlo@ and me and it works on our Armada XP - > based > systems. > > Please send your comment or remarks if there are any. > > Best regards > Zbigniew Bodek > > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" >