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authorOlof Johansson <olof@lixom.net>2013-08-13 23:33:07 -0700
committerOlof Johansson <olof@lixom.net>2013-08-13 23:33:07 -0700
commit8b2496a22810531cb9157191cd0264bae8efeca0 (patch)
tree04b3e07e094df65b2ea083eea30af6ac9a15c34e /arch/alpha/include/asm/atomic.h
parentbee22087faf5bbf33fcb61e6c5e8f8ef7ebd77a5 (diff)
parent4380c39ad3efbe58d7ed3b6adf6e602b23402b1e (diff)
downloadop-kernel-dev-8b2496a22810531cb9157191cd0264bae8efeca0.zip
op-kernel-dev-8b2496a22810531cb9157191cd0264bae8efeca0.tar.gz
Merge tag 'v3.12-pwm-cleanup-for-olof' of git://github.com/tom3q/linux into next/cleanup
From Tomasz Figa: Here is the Samsung PWM cleanup series. Particular patches of the series involve following modifications: - fixing up few things in samsung_pwm_timer clocksource driver, - moving remaining Samsung platforms to the new clocksource driver, - removing old clocksource driver, - adding new multiplatform- and DT-aware PWM driver, - moving all Samsung platforms to use the new PWM driver, - removing old PWM driver, - removing all PWM-related code that is not used anymore. * tag 'v3.12-pwm-cleanup-for-olof' of git://github.com/tom3q/linux: (684 commits) ARM: SAMSUNG: Remove plat/regs-timer.h header ARM: SAMSUNG: Remove remaining uses of plat/regs-timer.h header ARM: SAMSUNG: Remove pwm-clock infrastructure ARM: SAMSUNG: Remove old PWM timer platform devices pwm: Remove superseded pwm-samsung-legacy driver ARM: SAMSUNG: Modify board files to use new PWM platform device ARM: SAMSUNG: Rework private data handling in dev-backlight pwm: Add new pwm-samsung driver pwm: samsung: Rename to pwm-samsung-legacy ARM: SAMSUNG: Remove unused PWM timer IRQ chip code ARM: SAMSUNG: Remove old samsung-time driver ARM: SAMSUNG: Move all platforms to new clocksource driver ARM: SAMSUNG: Set PWM platform data ARM: SAMSUNG: Add new PWM platform device ARM: SAMSUNG: Unify base address definitions of timer block clocksource: samsung_pwm_timer: Handle suspend/resume correctly clocksource: samsung_pwm_timer: Do not use clocksource_mmio clocksource: samsung_pwm_timer: Cache clocksource register address clocksource: samsung_pwm_timer: Correct definition of AUTORELOAD bit clocksource: samsung_pwm_timer: Do not request PWM mem region + v3.11-rc4 Conflicts: arch/arm/Kconfig.debug Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/alpha/include/asm/atomic.h')
-rw-r--r--arch/alpha/include/asm/atomic.h88
1 files changed, 65 insertions, 23 deletions
diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h
index c2cbe4f..78b03ef 100644
--- a/arch/alpha/include/asm/atomic.h
+++ b/arch/alpha/include/asm/atomic.h
@@ -186,17 +186,24 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t * v)
*/
static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
- int c, old;
- c = atomic_read(v);
- for (;;) {
- if (unlikely(c == (u)))
- break;
- old = atomic_cmpxchg((v), c, c + (a));
- if (likely(old == c))
- break;
- c = old;
- }
- return c;
+ int c, new, old;
+ smp_mb();
+ __asm__ __volatile__(
+ "1: ldl_l %[old],%[mem]\n"
+ " cmpeq %[old],%[u],%[c]\n"
+ " addl %[old],%[a],%[new]\n"
+ " bne %[c],2f\n"
+ " stl_c %[new],%[mem]\n"
+ " beq %[new],3f\n"
+ "2:\n"
+ ".subsection 2\n"
+ "3: br 1b\n"
+ ".previous"
+ : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c)
+ : [mem] "m"(*v), [a] "rI"(a), [u] "rI"((long)u)
+ : "memory");
+ smp_mb();
+ return old;
}
@@ -207,21 +214,56 @@ static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns the old value of @v.
+ * Returns true iff @v was not @u.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
- long c, old;
- c = atomic64_read(v);
- for (;;) {
- if (unlikely(c == (u)))
- break;
- old = atomic64_cmpxchg((v), c, c + (a));
- if (likely(old == c))
- break;
- c = old;
- }
- return c != (u);
+ long c, tmp;
+ smp_mb();
+ __asm__ __volatile__(
+ "1: ldq_l %[tmp],%[mem]\n"
+ " cmpeq %[tmp],%[u],%[c]\n"
+ " addq %[tmp],%[a],%[tmp]\n"
+ " bne %[c],2f\n"
+ " stq_c %[tmp],%[mem]\n"
+ " beq %[tmp],3f\n"
+ "2:\n"
+ ".subsection 2\n"
+ "3: br 1b\n"
+ ".previous"
+ : [tmp] "=&r"(tmp), [c] "=&r"(c)
+ : [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u)
+ : "memory");
+ smp_mb();
+ return !c;
+}
+
+/*
+ * atomic64_dec_if_positive - decrement by 1 if old value positive
+ * @v: pointer of type atomic_t
+ *
+ * The function returns the old value of *v minus 1, even if
+ * the atomic variable, v, was not decremented.
+ */
+static inline long atomic64_dec_if_positive(atomic64_t *v)
+{
+ long old, tmp;
+ smp_mb();
+ __asm__ __volatile__(
+ "1: ldq_l %[old],%[mem]\n"
+ " subq %[old],1,%[tmp]\n"
+ " ble %[old],2f\n"
+ " stq_c %[tmp],%[mem]\n"
+ " beq %[tmp],3f\n"
+ "2:\n"
+ ".subsection 2\n"
+ "3: br 1b\n"
+ ".previous"
+ : [old] "=&r"(old), [tmp] "=&r"(tmp)
+ : [mem] "m"(*v)
+ : "memory");
+ smp_mb();
+ return old - 1;
}
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
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