Fix the arswitch instability problem. It turns out that the

arswitch_writereg() routine was writing the registers in the wrong order.

Revert -r241918 as the root problem is now fixed. Remove another workaround
from arswitch_ar7240.c.

Simplify and fix the code on arswitch_writephy() by using
arswitch_writereg().

While here remove a redundant declaration from arswitchvar.h.

Approved by:	adrian (mentor)

4 files changed, 9 insertions, 27 deletions

diff --git a/sys/dev/etherswitch/arswitch/arswitch_7240.c b/sys/dev/etherswitch/arswitch/arswitch_7240.c
index c8f6426..63a8910 100644
--- a/sys/dev/etherswitch/arswitch/arswitch_7240.c
+++ b/sys/dev/etherswitch/arswitch/arswitch_7240.c
@@ -75,12 +75,6 @@ ar7240_hw_setup(struct arswitch_softc *sc)
 	arswitch_writereg(sc->sc_dev, AR8X16_REG_CPU_PORT,
 	    AR8X16_CPU_PORT_EN | AR8X16_CPU_MIRROR_DIS);
 
-	/*
-	 * Let things settle; probing PHY4 doesn't seem reliable
-	 * without a litle delay.
-	 */
-	DELAY(1000);
-
 	return (0);
 }
 
diff --git a/sys/dev/etherswitch/arswitch/arswitch_phy.c b/sys/dev/etherswitch/arswitch/arswitch_phy.c
index f896d42..8e190e2 100644
--- a/sys/dev/etherswitch/arswitch/arswitch_phy.c
+++ b/sys/dev/etherswitch/arswitch/arswitch_phy.c
@@ -127,16 +127,13 @@ arswitch_writephy(device_t dev, int phy, int reg, int data)
 		return (ENXIO);
 
 	ARSWITCH_LOCK(sc);
-	err = arswitch_writereg_lsb(dev, AR8X16_REG_MDIO_CTRL,
-	    (data & AR8X16_MDIO_CTRL_DATA_MASK));
-	if (err != 0)
-		goto out;
-	err = arswitch_writereg_msb(dev, AR8X16_REG_MDIO_CTRL,
+	err = arswitch_writereg(dev, AR8X16_REG_MDIO_CTRL,
 	    AR8X16_MDIO_CTRL_BUSY |
 	    AR8X16_MDIO_CTRL_MASTER_EN |
 	    AR8X16_MDIO_CTRL_CMD_WRITE |
 	    (phy << AR8X16_MDIO_CTRL_PHY_ADDR_SHIFT) |
-	    (reg << AR8X16_MDIO_CTRL_REG_ADDR_SHIFT));
+	    (reg << AR8X16_MDIO_CTRL_REG_ADDR_SHIFT) |
+	    (data & AR8X16_MDIO_CTRL_DATA_MASK));
 	if (err != 0)
 		goto out;
 	for (timeout = 100; timeout--; ) {
diff --git a/sys/dev/etherswitch/arswitch/arswitch_reg.c b/sys/dev/etherswitch/arswitch/arswitch_reg.c
index 4ec71ba..2c31c9f 100644
--- a/sys/dev/etherswitch/arswitch/arswitch_reg.c
+++ b/sys/dev/etherswitch/arswitch/arswitch_reg.c
@@ -72,17 +72,10 @@ arswitch_split_setpage(device_t dev, uint32_t addr, uint16_t *phy,
 	*phy = (((addr) >> 6) & 0x07) | 0x10;
 	*reg = ((addr) >> 1) & 0x1f;
 
-	/*
-	 * The earlier code would only switch the page
-	 * over if the page were different.  Experiments have
-	 * shown that this is unstable.
-	 *
-	 * Hence, the page is always set here.
-	 *
-	 * See PR kern/172968
-	 */
-	MDIO_WRITEREG(device_get_parent(dev), 0x18, 0, page);
-	sc->page = page;
+	if (sc->page != page) {
+		MDIO_WRITEREG(device_get_parent(dev), 0x18, 0, page);
+		sc->page = page;
+	}
 }
 
 /*
@@ -171,8 +164,8 @@ arswitch_writereg(device_t dev, int addr, int value)
 {
 
 	/* XXX Check the first write too? */
-	arswitch_writereg_lsb(dev, addr, value);
-	return (arswitch_writereg_msb(dev, addr, value));
+	arswitch_writereg_msb(dev, addr, value);
+	return (arswitch_writereg_lsb(dev, addr, value));
 }
 
 int
diff --git a/sys/dev/etherswitch/arswitch/arswitchvar.h b/sys/dev/etherswitch/arswitch/arswitchvar.h
index 40e38a4..caf1c1f 100644
--- a/sys/dev/etherswitch/arswitch/arswitchvar.h
+++ b/sys/dev/etherswitch/arswitch/arswitchvar.h
@@ -42,8 +42,6 @@ typedef enum {
 #define	AR8X16_IS_SWITCH(_sc, _type) \
 	    (!!((_sc)->sc_switchtype == AR8X16_SWITCH_ ## _type))
 
-struct arswitch_softc;
-
 struct arswitch_softc {
 	struct mtx	sc_mtx;		/* serialize access to softc */
 	device_t	sc_dev;