summaryrefslogtreecommitdiff
path: root/include/asm-m32r/spinlock.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/asm-m32r/spinlock.h')
-rw-r--r--include/asm-m32r/spinlock.h380
1 files changed, 380 insertions, 0 deletions
diff --git a/include/asm-m32r/spinlock.h b/include/asm-m32r/spinlock.h
new file mode 100644
index 000000000000..6608d8371c50
--- /dev/null
+++ b/include/asm-m32r/spinlock.h
@@ -0,0 +1,380 @@
+#ifndef _ASM_M32R_SPINLOCK_H
+#define _ASM_M32R_SPINLOCK_H
+
+/*
+ * linux/include/asm-m32r/spinlock.h
+ *
+ * M32R version:
+ * Copyright (C) 2001, 2002 Hitoshi Yamamoto
+ * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
+ */
+
+#include <linux/config.h> /* CONFIG_DEBUG_SPINLOCK, CONFIG_SMP */
+#include <linux/compiler.h>
+#include <asm/atomic.h>
+#include <asm/page.h>
+
+extern int printk(const char * fmt, ...)
+ __attribute__ ((format (printf, 1, 2)));
+
+#define RW_LOCK_BIAS 0x01000000
+#define RW_LOCK_BIAS_STR "0x01000000"
+
+/*
+ * Your basic SMP spinlocks, allowing only a single CPU anywhere
+ */
+
+typedef struct {
+ volatile int slock;
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned magic;
+#endif
+#ifdef CONFIG_PREEMPT
+ unsigned int break_lock;
+#endif
+} spinlock_t;
+
+#define SPINLOCK_MAGIC 0xdead4ead
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+#define SPINLOCK_MAGIC_INIT , SPINLOCK_MAGIC
+#else
+#define SPINLOCK_MAGIC_INIT /* */
+#endif
+
+#define SPIN_LOCK_UNLOCKED (spinlock_t) { 1 SPINLOCK_MAGIC_INIT }
+
+#define spin_lock_init(x) do { *(x) = SPIN_LOCK_UNLOCKED; } while(0)
+
+/*
+ * Simple spin lock operations. There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * We make no fairness assumptions. They have a cost.
+ */
+
+#define spin_is_locked(x) (*(volatile int *)(&(x)->slock) <= 0)
+#define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x))
+#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
+
+/**
+ * _raw_spin_trylock - Try spin lock and return a result
+ * @lock: Pointer to the lock variable
+ *
+ * _raw_spin_trylock() tries to get the lock and returns a result.
+ * On the m32r, the result value is 1 (= Success) or 0 (= Failure).
+ */
+static inline int _raw_spin_trylock(spinlock_t *lock)
+{
+ int oldval;
+ unsigned long tmp1, tmp2;
+
+ /*
+ * lock->slock : =1 : unlock
+ * : <=0 : lock
+ * {
+ * oldval = lock->slock; <--+ need atomic operation
+ * lock->slock = 0; <--+
+ * }
+ */
+ __asm__ __volatile__ (
+ "# spin_trylock \n\t"
+ "ldi %1, #0; \n\t"
+ "mvfc %2, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r6", "%3")
+ "lock %0, @%3; \n\t"
+ "unlock %1, @%3; \n\t"
+ "mvtc %2, psw; \n\t"
+ : "=&r" (oldval), "=&r" (tmp1), "=&r" (tmp2)
+ : "r" (&lock->slock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r6"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+
+ return (oldval > 0);
+}
+
+static inline void _raw_spin_lock(spinlock_t *lock)
+{
+ unsigned long tmp0, tmp1;
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ if (unlikely(lock->magic != SPINLOCK_MAGIC)) {
+ printk("pc: %p\n", __builtin_return_address(0));
+ BUG();
+ }
+#endif
+ /*
+ * lock->slock : =1 : unlock
+ * : <=0 : lock
+ *
+ * for ( ; ; ) {
+ * lock->slock -= 1; <-- need atomic operation
+ * if (lock->slock == 0) break;
+ * for ( ; lock->slock <= 0 ; );
+ * }
+ */
+ __asm__ __volatile__ (
+ "# spin_lock \n\t"
+ ".fillinsn \n"
+ "1: \n\t"
+ "mvfc %1, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r6", "%2")
+ "lock %0, @%2; \n\t"
+ "addi %0, #-1; \n\t"
+ "unlock %0, @%2; \n\t"
+ "mvtc %1, psw; \n\t"
+ "bltz %0, 2f; \n\t"
+ LOCK_SECTION_START(".balign 4 \n\t")
+ ".fillinsn \n"
+ "2: \n\t"
+ "ld %0, @%2; \n\t"
+ "bgtz %0, 1b; \n\t"
+ "bra 2b; \n\t"
+ LOCK_SECTION_END
+ : "=&r" (tmp0), "=&r" (tmp1)
+ : "r" (&lock->slock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r6"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+}
+
+static inline void _raw_spin_unlock(spinlock_t *lock)
+{
+#ifdef CONFIG_DEBUG_SPINLOCK
+ BUG_ON(lock->magic != SPINLOCK_MAGIC);
+ BUG_ON(!spin_is_locked(lock));
+#endif
+ mb();
+ lock->slock = 1;
+}
+
+/*
+ * Read-write spinlocks, allowing multiple readers
+ * but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts
+ * but no interrupt writers. For those circumstances we
+ * can "mix" irq-safe locks - any writer needs to get a
+ * irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ */
+typedef struct {
+ volatile int lock;
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned magic;
+#endif
+#ifdef CONFIG_PREEMPT
+ unsigned int break_lock;
+#endif
+} rwlock_t;
+
+#define RWLOCK_MAGIC 0xdeaf1eed
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+#define RWLOCK_MAGIC_INIT , RWLOCK_MAGIC
+#else
+#define RWLOCK_MAGIC_INIT /* */
+#endif
+
+#define RW_LOCK_UNLOCKED (rwlock_t) { RW_LOCK_BIAS RWLOCK_MAGIC_INIT }
+
+#define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while(0)
+
+/**
+ * read_can_lock - would read_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define read_can_lock(x) ((int)(x)->lock > 0)
+
+/**
+ * write_can_lock - would write_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define write_can_lock(x) ((x)->lock == RW_LOCK_BIAS)
+
+/*
+ * On x86, we implement read-write locks as a 32-bit counter
+ * with the high bit (sign) being the "contended" bit.
+ *
+ * The inline assembly is non-obvious. Think about it.
+ *
+ * Changed to use the same technique as rw semaphores. See
+ * semaphore.h for details. -ben
+ */
+/* the spinlock helpers are in arch/i386/kernel/semaphore.c */
+
+static inline void _raw_read_lock(rwlock_t *rw)
+{
+ unsigned long tmp0, tmp1;
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ BUG_ON(rw->magic != RWLOCK_MAGIC);
+#endif
+ /*
+ * rw->lock : >0 : unlock
+ * : <=0 : lock
+ *
+ * for ( ; ; ) {
+ * rw->lock -= 1; <-- need atomic operation
+ * if (rw->lock >= 0) break;
+ * rw->lock += 1; <-- need atomic operation
+ * for ( ; rw->lock <= 0 ; );
+ * }
+ */
+ __asm__ __volatile__ (
+ "# read_lock \n\t"
+ ".fillinsn \n"
+ "1: \n\t"
+ "mvfc %1, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r6", "%2")
+ "lock %0, @%2; \n\t"
+ "addi %0, #-1; \n\t"
+ "unlock %0, @%2; \n\t"
+ "mvtc %1, psw; \n\t"
+ "bltz %0, 2f; \n\t"
+ LOCK_SECTION_START(".balign 4 \n\t")
+ ".fillinsn \n"
+ "2: \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r6", "%2")
+ "lock %0, @%2; \n\t"
+ "addi %0, #1; \n\t"
+ "unlock %0, @%2; \n\t"
+ "mvtc %1, psw; \n\t"
+ ".fillinsn \n"
+ "3: \n\t"
+ "ld %0, @%2; \n\t"
+ "bgtz %0, 1b; \n\t"
+ "bra 3b; \n\t"
+ LOCK_SECTION_END
+ : "=&r" (tmp0), "=&r" (tmp1)
+ : "r" (&rw->lock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r6"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+}
+
+static inline void _raw_write_lock(rwlock_t *rw)
+{
+ unsigned long tmp0, tmp1, tmp2;
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ BUG_ON(rw->magic != RWLOCK_MAGIC);
+#endif
+ /*
+ * rw->lock : =RW_LOCK_BIAS_STR : unlock
+ * : !=RW_LOCK_BIAS_STR : lock
+ *
+ * for ( ; ; ) {
+ * rw->lock -= RW_LOCK_BIAS_STR; <-- need atomic operation
+ * if (rw->lock == 0) break;
+ * rw->lock += RW_LOCK_BIAS_STR; <-- need atomic operation
+ * for ( ; rw->lock != RW_LOCK_BIAS_STR ; ) ;
+ * }
+ */
+ __asm__ __volatile__ (
+ "# write_lock \n\t"
+ "seth %1, #high(" RW_LOCK_BIAS_STR "); \n\t"
+ "or3 %1, %1, #low(" RW_LOCK_BIAS_STR "); \n\t"
+ ".fillinsn \n"
+ "1: \n\t"
+ "mvfc %2, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r7", "%3")
+ "lock %0, @%3; \n\t"
+ "sub %0, %1; \n\t"
+ "unlock %0, @%3; \n\t"
+ "mvtc %2, psw; \n\t"
+ "bnez %0, 2f; \n\t"
+ LOCK_SECTION_START(".balign 4 \n\t")
+ ".fillinsn \n"
+ "2: \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r7", "%3")
+ "lock %0, @%3; \n\t"
+ "add %0, %1; \n\t"
+ "unlock %0, @%3; \n\t"
+ "mvtc %2, psw; \n\t"
+ ".fillinsn \n"
+ "3: \n\t"
+ "ld %0, @%3; \n\t"
+ "beq %0, %1, 1b; \n\t"
+ "bra 3b; \n\t"
+ LOCK_SECTION_END
+ : "=&r" (tmp0), "=&r" (tmp1), "=&r" (tmp2)
+ : "r" (&rw->lock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r7"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+}
+
+static inline void _raw_read_unlock(rwlock_t *rw)
+{
+ unsigned long tmp0, tmp1;
+
+ __asm__ __volatile__ (
+ "# read_unlock \n\t"
+ "mvfc %1, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r6", "%2")
+ "lock %0, @%2; \n\t"
+ "addi %0, #1; \n\t"
+ "unlock %0, @%2; \n\t"
+ "mvtc %1, psw; \n\t"
+ : "=&r" (tmp0), "=&r" (tmp1)
+ : "r" (&rw->lock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r6"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+}
+
+static inline void _raw_write_unlock(rwlock_t *rw)
+{
+ unsigned long tmp0, tmp1, tmp2;
+
+ __asm__ __volatile__ (
+ "# write_unlock \n\t"
+ "seth %1, #high(" RW_LOCK_BIAS_STR "); \n\t"
+ "or3 %1, %1, #low(" RW_LOCK_BIAS_STR "); \n\t"
+ "mvfc %2, psw; \n\t"
+ "clrpsw #0x40 -> nop; \n\t"
+ DCACHE_CLEAR("%0", "r7", "%3")
+ "lock %0, @%3; \n\t"
+ "add %0, %1; \n\t"
+ "unlock %0, @%3; \n\t"
+ "mvtc %2, psw; \n\t"
+ : "=&r" (tmp0), "=&r" (tmp1), "=&r" (tmp2)
+ : "r" (&rw->lock)
+ : "memory"
+#ifdef CONFIG_CHIP_M32700_TS1
+ , "r7"
+#endif /* CONFIG_CHIP_M32700_TS1 */
+ );
+}
+
+#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
+
+static inline int _raw_write_trylock(rwlock_t *lock)
+{
+ atomic_t *count = (atomic_t *)lock;
+ if (atomic_sub_and_test(RW_LOCK_BIAS, count))
+ return 1;
+ atomic_add(RW_LOCK_BIAS, count);
+ return 0;
+}
+
+#endif /* _ASM_M32R_SPINLOCK_H */
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-09 14:00:03 +0000