svn commit: r296905 - head/sys/dev/extres/clk

[Michal Meloun]

Author: mmel
Date: Tue Mar 15 15:28:24 2016
New Revision: 296905
URL: https://svnweb.freebsd.org/changeset/base/296905

Log:
  CLK: Add and use explicit locking for access to clock device registers.
  Implicit locking (for read/write/modify) is not sufficient for complex
  cases.

Modified:
  head/sys/dev/extres/clk/clk_div.c
  head/sys/dev/extres/clk/clk_gate.c
  head/sys/dev/extres/clk/clk_mux.c
  head/sys/dev/extres/clk/clkdev_if.m

Modified: head/sys/dev/extres/clk/clk_div.c
==============================================================================
--- head/sys/dev/extres/clk/clk_div.c	Tue Mar 15 15:27:15 2016	(r296904)
+++ head/sys/dev/extres/clk/clk_div.c	Tue Mar 15 15:28:24 2016	(r296905)
@@ -46,6 +46,10 @@ __FBSDID("$FreeBSD$");
 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
 #define	MD4(_clk, off, clr, set )					\
 	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
+#define	DEVICE_LOCK(_clk)							\
+	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
+#define	DEVICE_UNLOCK(_clk)						\
+	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
 
 static int clknode_div_init(struct clknode *clk, device_t dev);
 static int clknode_div_recalc(struct clknode *clk, uint64_t *req);
@@ -86,7 +90,9 @@ clknode_div_init(struct clknode *clk, de
 
 	sc = clknode_get_softc(clk);
 
+	DEVICE_LOCK(clk);
 	rv = RD4(clk, sc->offset, &reg);
+	DEVICE_UNLOCK(clk);
 	if (rv != 0)
 		return (rv);
 
@@ -171,12 +177,17 @@ clknode_div_set_freq(struct clknode *clk
 		    (*fout != (_fin / divider)))
 			return (ERANGE);
 
+		DEVICE_LOCK(clk);
 		rv = MD4(clk, sc->offset,
 		    (sc->i_mask << sc->i_shift) | (sc->f_mask << sc->f_shift),
 		    (i_div << sc->i_shift) | (f_div << sc->f_shift));
-		if (rv != 0)
+		if (rv != 0) {
+			DEVICE_UNLOCK(clk);
 			return (rv);
+		}
 		RD4(clk, sc->offset, &reg);
+		DEVICE_UNLOCK(clk);
+
 		sc->divider = divider;
 	}
 

Modified: head/sys/dev/extres/clk/clk_gate.c
==============================================================================
--- head/sys/dev/extres/clk/clk_gate.c	Tue Mar 15 15:27:15 2016	(r296904)
+++ head/sys/dev/extres/clk/clk_gate.c	Tue Mar 15 15:28:24 2016	(r296905)
@@ -46,7 +46,10 @@ __FBSDID("$FreeBSD$");
 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
 #define	MD4(_clk, off, clr, set )					\
 	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
-
+#define	DEVICE_LOCK(_clk)							\
+	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
+#define	DEVICE_UNLOCK(_clk)						\
+	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
 
 static int clknode_gate_init(struct clknode *clk, device_t dev);
 static int clknode_gate_set_gate(struct clknode *clk, bool enable);
@@ -77,7 +80,9 @@ clknode_gate_init(struct clknode *clk, d
 	int rv;
 
 	sc = clknode_get_softc(clk);
+	DEVICE_LOCK(clk);
 	rv = RD4(clk, sc->offset, &reg);
+	DEVICE_UNLOCK(clk);
 	if (rv != 0)
 		return (rv);
 	reg = (reg >> sc->shift) & sc->mask;
@@ -95,11 +100,15 @@ clknode_gate_set_gate(struct clknode *cl
 
 	sc = clknode_get_softc(clk);
 	sc->ungated = enable;
+	DEVICE_LOCK(clk);
 	rv = MD4(clk, sc->offset, sc->mask << sc->shift,
 	    (sc->ungated ? sc->on_value : sc->off_value) << sc->shift);
-	if (rv != 0)
+	if (rv != 0) {
+		DEVICE_UNLOCK(clk);
 		return (rv);
+	}
 	RD4(clk, sc->offset, &reg);
+	DEVICE_UNLOCK(clk);
 	return(0);
 }
 

Modified: head/sys/dev/extres/clk/clk_mux.c
==============================================================================
--- head/sys/dev/extres/clk/clk_mux.c	Tue Mar 15 15:27:15 2016	(r296904)
+++ head/sys/dev/extres/clk/clk_mux.c	Tue Mar 15 15:28:24 2016	(r296905)
@@ -46,6 +46,10 @@ __FBSDID("$FreeBSD$");
 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
 #define	MD4(_clk, off, clr, set )					\
 	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
+#define	DEVICE_LOCK(_clk)							\
+	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
+#define	DEVICE_UNLOCK(_clk)						\
+	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
 
 static int clknode_mux_init(struct clknode *clk, device_t dev);
 static int clknode_mux_set_mux(struct clknode *clk, int idx);
@@ -76,9 +80,12 @@ clknode_mux_init(struct clknode *clk, de
 
 	sc = clknode_get_softc(clk);
 
+	DEVICE_LOCK(clk);
 	rv = RD4(clk, sc->offset, &reg);
-	if (rv != 0)
+	DEVICE_UNLOCK(clk);
+	if (rv != 0) {
 		return (rv);
+	}
 	reg = (reg >> sc->shift) & sc->mask;
 	clknode_init_parent_idx(clk, reg);
 	return(0);
@@ -93,11 +100,16 @@ clknode_mux_set_mux(struct clknode *clk,
 
 	sc = clknode_get_softc(clk);
 
+	DEVICE_LOCK(clk);
 	rv = MD4(clk, sc->offset, sc->mask << sc->shift,
 	    (idx & sc->mask) << sc->shift);
-	if (rv != 0)
+	if (rv != 0) {
+		DEVICE_UNLOCK(clk);
 		return (rv);
+	}
 	RD4(clk, sc->offset, &reg);
+	DEVICE_UNLOCK(clk);
+
 	return(0);
 }
 

Modified: head/sys/dev/extres/clk/clkdev_if.m
==============================================================================
--- head/sys/dev/extres/clk/clkdev_if.m	Tue Mar 15 15:27:15 2016	(r296904)
+++ head/sys/dev/extres/clk/clkdev_if.m	Tue Mar 15 15:28:24 2016	(r296905)
@@ -30,6 +30,23 @@
 
 INTERFACE clkdev;
 
+CODE {
+	#include <sys/systm.h>
+	static void
+	clkdev_default_device_lock(device_t dev)
+	{
+
+		panic("clkdev_device_lock() is not implemented");
+	}
+
+	static void
+	clkdev_default_device_unlock(device_t dev)
+	{
+
+		panic("clkdev_device_unlock() is not implemented");
+	}
+}
+
 #
 # Write single register
 #
@@ -57,3 +74,17 @@ METHOD int modify_4 {
 	uint32_t	clear_mask;
 	uint32_t	set_mask;
 };
+
+#
+# Get exclusive access to underlying device
+#
+METHOD void device_lock {
+	device_t	dev;
+} DEFAULT clkdev_default_device_lock;
+
+#
+# Release exclusive access to underlying device
+#
+METHOD void device_unlock {
+	device_t	dev;
+} DEFAULT clkdev_default_device_unlock;