MFC r257170, r257171, r257172, r257240, r257278, r257279, r257280, r257281,

    r257282, r257332

  Wait for DesignWare UART transfers completion before accessing line control

  Enable UART busy detection handling for Armada XP - based board

  Enable SATA interface on Armada XP
  Run mvs SATA driver on Armada XP instead of old mv_sata

  Retire arm_remap_nocache() and the data and constants associated with it.

  Remove hard-coded mappings related to Armada XP support

  Fix-up DTB for Armada XP registers' base according to the actual settings

  Change Armada XP kernel load address to the u-boot's end address

  Remove not working and deprecated PJ4Bv6 support

  Switch off explicit broadcasting of the TLB flush operations for PJ4B CPU

  Add missing ARMv6 CPU functions to ARM Makefile

1 files changed, 25 insertions, 1 deletions

diff --git a/sys/dev/uart/uart_dev_ns8250.c b/sys/dev/uart/uart_dev_ns8250.c
index 31b1aba..47a61bf 100644
--- a/sys/dev/uart/uart_dev_ns8250.c
+++ b/sys/dev/uart/uart_dev_ns8250.c
@@ -649,11 +649,35 @@ int
 ns8250_bus_param(struct uart_softc *sc, int baudrate, int databits,
     int stopbits, int parity)
 {
+	struct ns8250_softc *ns8250;
 	struct uart_bas *bas;
-	int error;
+	int error, limit;
 
+	ns8250 = (struct ns8250_softc*)sc;
 	bas = &sc->sc_bas;
 	uart_lock(sc->sc_hwmtx);
+	/*
+	 * When using DW UART with BUSY detection it is necessary to wait
+	 * until all serial transfers are finished before manipulating the
+	 * line control. LCR will not be affected when UART is busy.
+	 */
+	if (ns8250->busy_detect != 0) {
+		/*
+		 * Pick an arbitrary high limit to avoid getting stuck in
+		 * an infinite loop in case when the hardware is broken.
+		 */
+		limit = 10 * 1024;
+		while (((uart_getreg(bas, DW_REG_USR) & USR_BUSY) != 0) &&
+		    --limit)
+			DELAY(4);
+
+		if (limit <= 0) {
+			/* UART appears to be stuck */
+			uart_unlock(sc->sc_hwmtx);
+			return (EIO);
+		}
+	}
+
 	error = ns8250_param(bas, baudrate, databits, stopbits, parity);
 	uart_unlock(sc->sc_hwmtx);
 	return (error);