[PATCH] serial: imx: add console polling routines for kgdboc

[PATCH] serial: imx: add console polling routines for kgdboc

[Atsuo Igarashi]

[-- Attachment #1: Type: text/plain, Size: 123 bytes --]

Add console polling routines for the imx uart with kgdboc.

Signed-off-by Atsuo Igarashi <atsuo_igarashi@tripeaks.co.jp>



[-- Attachment #2: imx_serial_for_kgdb.diff --]
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--- linux-2.6.orig/drivers/serial/imx.c	2008-08-13 15:06:45.000000000 +0900
+++ linux-2.6/drivers/serial/imx.c	2008-08-13 15:10:59.000000000 +0900
@@ -646,6 +646,29 @@ static void imx_shutdown(struct uart_por
 	writel(temp, sport->port.membase + UCR1);
 }
 
+#ifdef CONFIG_CONSOLE_POLL
+
+static int imx_get_poll_char(struct uart_port *port)
+{
+	struct imx_port *sport = (struct imx_port *)port;
+
+	while (!(readl(sport->port.membase + USR2) & USR2_RDR));
+
+	return readl(sport->port.membase + URXD0);
+}
+
+static void imx_put_poll_char(struct uart_port *port, unsigned char ch)
+{
+	struct imx_port *sport = (struct imx_port *)port;
+
+	while (readl(sport->port.membase + UTS) & UTS_TXFULL)
+		barrier();
+
+	writel(ch, sport->port.membase + URTX0);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
 static void
 imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		   struct ktermios *old)
@@ -892,6 +915,10 @@ static struct uart_ops imx_pops = {
 	.request_port	= imx_request_port,
 	.config_port	= imx_config_port,
 	.verify_port	= imx_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_get_char	= imx_get_poll_char,
+	.poll_put_char	= imx_put_poll_char,
+#endif
 };
 
 static struct imx_port *imx_ports[UART_NR];

Re: [PATCH] serial: imx: add console polling routines for kgdboc

[Sascha Hauer]

On Wed, Aug 13, 2008 at 05:27:39PM +0900, Atsuo Igarashi wrote:
> Add console polling routines for the imx uart with kgdboc.

Thanks very much. I've never tried kgdb, so I cannot say if this patch
does the right thing, but it looks like it does ;)
I added it to our git tree.

Sascha


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Re: [PATCH] serial: imx: add console polling routines for kgdboc

[Andrew Dyer]

On Wed, Aug 13, 2008 at 3:27 AM, Atsuo Igarashi
<atsuo_igarashi@tripeaks.co.jp> wrote:
> Add console polling routines for the imx uart with kgdboc.
>
> Signed-off-by Atsuo Igarashi <atsuo_igarashi@tripeaks.co.jp>
>

In imx_get_poll_char() the code returns the result of reading the urxd
register.  That register has the 8 bits of receive data in it, but in
the next byte up also has 4 bits of error flags (overrun, frame,
break, parity) and an error summary bit which are being ignored.
Maybe something like this?

static int imx_get_poll_char(struct uart_port *port)
{
	struct imx_port *sport = (struct imx_port *)port;
	int ch;

	while (1) {
                while (!(readl(sport->port.membase + USR2) & USR2_RDR));

	        ch = readl(sport->port.membase + URXD0);

                if (!(ch & URXD_ERR))
                        return(ch & 0xff);
                /* else throw away the char with the error and try
again (or return an error value?) */
        }
}


-- 
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