From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by casper.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1S7Rjq-0004x6-39 for barebox@lists.infradead.org; Tue, 13 Mar 2012 13:26:07 +0000 Received: from gallifrey.ext.pengutronix.de ([2001:6f8:1178:4:5054:ff:fe8d:eefb] helo=localhost) by metis.ext.pengutronix.de with esmtp (Exim 4.72) (envelope-from ) id 1S7Rjl-0003TD-GA for barebox@lists.infradead.org; Tue, 13 Mar 2012 14:26:01 +0100 From: Juergen Beisert Date: Tue, 13 Mar 2012 14:25:49 +0100 References: <201203131416.47776.jbe@pengutronix.de> In-Reply-To: <201203131416.47776.jbe@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline Message-Id: <201203131425.49344.jbe@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [RFC] ARM/serial: add a DCC based console driver To: barebox@lists.infradead.org Myself wrote: > [...] > Sending chars via DCC blocks for ever, when I'm using a simple > while loop waiting for the DCC_OUTPUT_BUSY to be cleared. After adding a > timeout loop I receive every other char at the JTAG side. When I write the > char to the DCC even if it timeout, I receive *every* char. Only some cha= rs > are lost when I reduce the timeout value below 750 us. > Any idea? I checked the kernel source, but they doing the same: Waiting f= or > the DCC_OUTPUT_BUSY to be cleared and timeout after a specific amount of > loops (but without writing the char in this case). > [...] Forget about that. The dcc_serial_putc() is broken in this patch. My ARMv5 = *always* signals a DCC_OUTPUT_BUSY. If I ignore this bit and just wait abou= t = 750 =B5s between the chars it works as expected. Still have to find out, wh= y it = always signals a DCC_OUTPUT_BUSY... jbe -- = Pengutronix e.K. | Juergen Beisert = | Linux Solutions for Science and Industry | http://www.pengutronix.de/ = | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox