MFC: r260889, r260890, r260911:

	r260911 | imp | 2014-01-20 10:45:36 -0700 (Mon, 20 Jan 2014) | 5 lines

	Don't lock in the generic grab just to lock again in the specific grabs.

	r260890 | imp | 2014-01-19 12:39:13 -0700 (Sun, 19 Jan 2014) | 11 lines

	Introduce grab and ungrab upcalls. When the kernel desires to grab the
	console, it calls the grab functions. These functions should turn off
	the RX interrupts, and any others that interfere. This makes mountroot
	prompt work again. If there's more generalized need other than
	prompting, many of these routines should be expanded to do those new
	things.

	Reviewed by:    bde (with reservations)

1 files changed, 32 insertions, 0 deletions

diff --git a/sys/mips/atheros/uart_dev_ar933x.c b/sys/mips/atheros/uart_dev_ar933x.c
index 30f05ba..f719805 100644
--- a/sys/mips/atheros/uart_dev_ar933x.c
+++ b/sys/mips/atheros/uart_dev_ar933x.c
@@ -325,6 +325,8 @@ static int ar933x_bus_probe(struct uart_softc *);
 static int ar933x_bus_receive(struct uart_softc *);
 static int ar933x_bus_setsig(struct uart_softc *, int);
 static int ar933x_bus_transmit(struct uart_softc *);
+static void ar933x_bus_grab(struct uart_softc *);
+static void ar933x_bus_ungrab(struct uart_softc *);
 
 static kobj_method_t ar933x_methods[] = {
 	KOBJMETHOD(uart_attach,		ar933x_bus_attach),
@@ -338,6 +340,8 @@ static kobj_method_t ar933x_methods[] = {
 	KOBJMETHOD(uart_receive,	ar933x_bus_receive),
 	KOBJMETHOD(uart_setsig,		ar933x_bus_setsig),
 	KOBJMETHOD(uart_transmit,	ar933x_bus_transmit),
+	KOBJMETHOD(uart_grab,		ar933x_bus_grab),
+	KOBJMETHOD(uart_ungrab,		ar933x_bus_ungrab),
 	{ 0, 0 }
 };
 
@@ -752,3 +756,31 @@ ar933x_bus_transmit(struct uart_softc *sc)
 
 	return (0);
 }
+
+static void
+ar933x_bus_grab(struct uart_softc *sc)
+{
+	struct uart_bas *bas = &sc->sc_bas;
+	uint32_t reg;
+
+	/* Disable the host interrupt now */
+	uart_lock(sc->sc_hwmtx);
+	reg = ar933x_getreg(bas, AR933X_UART_CS_REG);
+	reg &= ~AR933X_UART_CS_HOST_INT_EN;
+	ar933x_setreg(bas, AR933X_UART_CS_REG, reg);
+	uart_unlock(sc->sc_hwmtx);
+}
+
+static void
+ar933x_bus_ungrab(struct uart_softc *sc)
+{
+	struct uart_bas *bas = &sc->sc_bas;
+	uint32_t reg;
+
+	/* Enable the host interrupt now */
+	uart_lock(sc->sc_hwmtx);
+	reg = ar933x_getreg(bas, AR933X_UART_CS_REG);
+	reg |= AR933X_UART_CS_HOST_INT_EN;
+	ar933x_setreg(bas, AR933X_UART_CS_REG, reg);
+	uart_unlock(sc->sc_hwmtx);
+}