PPC440: Add flow control for serial port (Third try)

This has be layouten tested on our HCU5 PPC440EPx based board, where we have only one serial port. Changes compared to my last try are:
- HW-flow control is off by default.
- returns the correct state of the hwflow
- coding style corrected

---
 cpu/ppc4xx/serial.c |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)

index 60712b1..8f36fef 100644
@@ -490,6 +490,31 @@ static void serial_divs (int baudrate, unsigned long *pudiv,
 }
 #endif /* defined(CONFIG_440) && !defined(CFG_EXT_SERIAL_CLK) */
 
+#if defined(CONFIG_CMD_HWFLOW) && defined(CONFIG_440) && !defined(CONFIG_SERIAL_MULTI)
+static int hwflow = 0; /* turned off by default */
+int hwflow_onoff(int on)
+{
+	switch(on) {
+	case 0:
+	default:
+		break; /* return current */
+	case 1:
+		/* The OUT2 bit may be written and read
+		 * but it provides no function
+		 */
+		out8(UART_BASE + UART_MCR, 0x0b);
+		hwflow = 1; /* turn on */
+		break;
+	case -1:
+		/* no modem control DTR RTS */
+		out8(UART_BASE + UART_MCR, 0x00);
+		hwflow = 0; /* turn off */
+		break;
+	}
+	return hwflow;
+}
+#endif
+
 /*
  * Minimal serial functions needed to use one of the SMC ports
  * as serial console interface.

1.5.2

I'm (finally) trying to integrate your patches into the u-boot-ppc4xx custodian repository for upstream merge. Unfortunately my repo changed quite a bit lately and your patches don't apply anymore. So could you please rebase this patchset against the "for-1.3.2" branch of the 4xx repo:

http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot/u-boot-ppc4xx.git;a=shortlog;h=for-1.3.2

I promise to commit soon so that you don't have to rework again.

Unfortunately this is valid also for this patch too:

[U-Boot-Users] PPC440EPx: Make Sequoia boot vxWorks

Thanks.

Best regards,
Stefan

=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office at denx.de
=====================================================================

Hi Niklaus,

Could you please re-check which patches of yours are still missing in the current official mainline U-Boot repository? And please rebase all missing patches and resend them. Then I'll try to get them in while we are still in this looooong merge-window.

Thanks.

Best regards,
Stefan

=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office at denx.de
=====================================================================