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CLK: Add and use explicit locking for access to clock device registers.

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Implicit locking (for read/write/modify) is not sufficient for complex
cases.
This commit is contained in:
mmel 2016-03-15 15:28:24 +00:00
parent a42e49208d
commit a2b0006e89
4 changed files with 68 additions and 5 deletions
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13
sys/dev/extres/clk/clk_div.c
View File

@ -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, device_t dev)
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, uint64_t fin, uint64_t *fout,
(*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;
}

13
sys/dev/extres/clk/clk_gate.c
View File

@ -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, device_t dev)
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 *clk, bool enable)
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);
}

16
sys/dev/extres/clk/clk_mux.c
View File

@ -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, device_t dev)
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, int idx)
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);
}

31
sys/dev/extres/clk/clkdev_if.m
View File

@ -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;