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-rw-r--r--arch/arc/include/asm/atomic.h99
-rw-r--r--arch/arc/include/asm/spinlock.h7
-rw-r--r--arch/arc/kernel/time.c63
3 files changed, 131 insertions, 38 deletions
diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h
index dd683995bc9d..4e3c1b6b0806 100644
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -67,6 +67,33 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return val; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned int val, orig; \
+ \
+ /* \
+ * Explicit full memory barrier needed before/after as \
+ * LLOCK/SCOND thmeselves don't provide any such semantics \
+ */ \
+ smp_mb(); \
+ \
+ __asm__ __volatile__( \
+ "1: llock %[orig], [%[ctr]] \n" \
+ " " #asm_op " %[val], %[orig], %[i] \n" \
+ " scond %[val], [%[ctr]] \n" \
+ " \n" \
+ : [val] "=&r" (val), \
+ [orig] "=&r" (orig) \
+ : [ctr] "r" (&v->counter), \
+ [i] "ir" (i) \
+ : "cc"); \
+ \
+ smp_mb(); \
+ \
+ return orig; \
+}
+
#else /* !CONFIG_ARC_HAS_LLSC */
#ifndef CONFIG_SMP
@@ -129,25 +156,44 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned long flags; \
+ unsigned long orig; \
+ \
+ /* \
+ * spin lock/unlock provides the needed smp_mb() before/after \
+ */ \
+ atomic_ops_lock(flags); \
+ orig = v->counter; \
+ v->counter c_op i; \
+ atomic_ops_unlock(flags); \
+ \
+ return orig; \
+}
+
#endif /* !CONFIG_ARC_HAS_LLSC */
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_OP_RETURN(op, c_op, asm_op)
+ ATOMIC_OP_RETURN(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
#define atomic_andnot atomic_andnot
-ATOMIC_OP(and, &=, and)
-ATOMIC_OP(andnot, &= ~, bic)
-ATOMIC_OP(or, |=, or)
-ATOMIC_OP(xor, ^=, xor)
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
-#undef SCOND_FAIL_RETRY_VAR_DEF
-#undef SCOND_FAIL_RETRY_ASM
-#undef SCOND_FAIL_RETRY_VARS
+ATOMIC_OPS(and, &=, and)
+ATOMIC_OPS(andnot, &= ~, bic)
+ATOMIC_OPS(or, |=, or)
+ATOMIC_OPS(xor, ^=, xor)
#else /* CONFIG_ARC_PLAT_EZNPS */
@@ -208,22 +254,51 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
+#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
+static inline int atomic_fetch_##op(int i, atomic_t *v) \
+{ \
+ unsigned int temp = i; \
+ \
+ /* Explicit full memory barrier needed before/after */ \
+ smp_mb(); \
+ \
+ __asm__ __volatile__( \
+ " mov r2, %0\n" \
+ " mov r3, %1\n" \
+ " .word %2\n" \
+ " mov %0, r2" \
+ : "+r"(temp) \
+ : "r"(&v->counter), "i"(asm_op) \
+ : "r2", "r3", "memory"); \
+ \
+ smp_mb(); \
+ \
+ return temp; \
+}
+
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_OP_RETURN(op, c_op, asm_op)
+ ATOMIC_OP_RETURN(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, CTOP_INST_AADD_DI_R2_R2_R3)
#define atomic_sub(i, v) atomic_add(-(i), (v))
#define atomic_sub_return(i, v) atomic_add_return(-(i), (v))
-ATOMIC_OP(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op) \
+ ATOMIC_OP(op, c_op, asm_op) \
+ ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
#define atomic_andnot(mask, v) atomic_and(~(mask), (v))
-ATOMIC_OP(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
-ATOMIC_OP(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
+ATOMIC_OPS(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
+ATOMIC_OPS(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
#endif /* CONFIG_ARC_PLAT_EZNPS */
#undef ATOMIC_OPS
+#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
diff --git a/arch/arc/include/asm/spinlock.h b/arch/arc/include/asm/spinlock.h
index cded4a9b5438..233d5ffe6ec7 100644
--- a/arch/arc/include/asm/spinlock.h
+++ b/arch/arc/include/asm/spinlock.h
@@ -15,8 +15,11 @@
#define arch_spin_is_locked(x) ((x)->slock != __ARCH_SPIN_LOCK_UNLOCKED__)
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
-#define arch_spin_unlock_wait(x) \
- do { while (arch_spin_is_locked(x)) cpu_relax(); } while (0)
+
+static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
+{
+ smp_cond_load_acquire(&lock->slock, !VAL);
+}
#ifdef CONFIG_ARC_HAS_LLSC
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 4549ab255dd1..98f22d2eb563 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -116,19 +116,19 @@ static struct clocksource arc_counter_gfrc = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static void __init arc_cs_setup_gfrc(struct device_node *node)
+static int __init arc_cs_setup_gfrc(struct device_node *node)
{
int exists = cpuinfo_arc700[0].extn.gfrc;
int ret;
if (WARN(!exists, "Global-64-bit-Ctr clocksource not detected"))
- return;
+ return -ENXIO;
ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;
- clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
}
CLOCKSOURCE_OF_DECLARE(arc_gfrc, "snps,archs-timer-gfrc", arc_cs_setup_gfrc);
@@ -172,25 +172,25 @@ static struct clocksource arc_counter_rtc = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static void __init arc_cs_setup_rtc(struct device_node *node)
+static int __init arc_cs_setup_rtc(struct device_node *node)
{
int exists = cpuinfo_arc700[smp_processor_id()].extn.rtc;
int ret;
if (WARN(!exists, "Local-64-bit-Ctr clocksource not detected"))
- return;
+ return -ENXIO;
/* Local to CPU hence not usable in SMP */
if (WARN(IS_ENABLED(CONFIG_SMP), "Local-64-bit-Ctr not usable in SMP"))
- return;
+ return -EINVAL;
ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;
write_aux_reg(AUX_RTC_CTRL, 1);
- clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
}
CLOCKSOURCE_OF_DECLARE(arc_rtc, "snps,archs-timer-rtc", arc_cs_setup_rtc);
@@ -213,23 +213,23 @@ static struct clocksource arc_counter_timer1 = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static void __init arc_cs_setup_timer1(struct device_node *node)
+static int __init arc_cs_setup_timer1(struct device_node *node)
{
int ret;
/* Local to CPU hence not usable in SMP */
if (IS_ENABLED(CONFIG_SMP))
- return;
+ return -EINVAL;
ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;
write_aux_reg(ARC_REG_TIMER1_LIMIT, ARC_TIMER_MAX);
write_aux_reg(ARC_REG_TIMER1_CNT, 0);
write_aux_reg(ARC_REG_TIMER1_CTRL, TIMER_CTRL_NH);
- clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
}
/********** Clock Event Device *********/
@@ -324,20 +324,28 @@ static struct notifier_block arc_timer_cpu_nb = {
/*
* clockevent setup for boot CPU
*/
-static void __init arc_clockevent_setup(struct device_node *node)
+static int __init arc_clockevent_setup(struct device_node *node)
{
struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
int ret;
- register_cpu_notifier(&arc_timer_cpu_nb);
+ ret = register_cpu_notifier(&arc_timer_cpu_nb);
+ if (ret) {
+ pr_err("Failed to register cpu notifier");
+ return ret;
+ }
arc_timer_irq = irq_of_parse_and_map(node, 0);
- if (arc_timer_irq <= 0)
- panic("clockevent: missing irq");
+ if (arc_timer_irq <= 0) {
+ pr_err("clockevent: missing irq");
+ return -EINVAL;
+ }
ret = arc_get_timer_clk(node);
- if (ret)
- panic("clockevent: missing clk");
+ if (ret) {
+ pr_err("clockevent: missing clk");
+ return ret;
+ }
evt->irq = arc_timer_irq;
evt->cpumask = cpumask_of(smp_processor_id());
@@ -347,22 +355,29 @@ static void __init arc_clockevent_setup(struct device_node *node)
/* Needs apriori irq_set_percpu_devid() done in intc map function */
ret = request_percpu_irq(arc_timer_irq, timer_irq_handler,
"Timer0 (per-cpu-tick)", evt);
- if (ret)
- panic("clockevent: unable to request irq\n");
+ if (ret) {
+ pr_err("clockevent: unable to request irq\n");
+ return ret;
+ }
enable_percpu_irq(arc_timer_irq, 0);
+
+ return 0;
}
-static void __init arc_of_timer_init(struct device_node *np)
+static int __init arc_of_timer_init(struct device_node *np)
{
static int init_count = 0;
+ int ret;
if (!init_count) {
init_count = 1;
- arc_clockevent_setup(np);
+ ret = arc_clockevent_setup(np);
} else {
- arc_cs_setup_timer1(np);
+ ret = arc_cs_setup_timer1(np);
}
+
+ return ret;
}
CLOCKSOURCE_OF_DECLARE(arc_clkevt, "snps,arc-timer", arc_of_timer_init);
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