1 files changed, 310 insertions, 0 deletions
diff --git a/include/asm-sparc64/spinlock.h b/include/asm-sparc64/spinlock.h
new file mode 100644
index 00000000000..11efa474865
--- /dev/null
+++ b/include/asm-sparc64/spinlock.h
@@ -0,0 +1,310 @@
+/* spinlock.h: 64-bit Sparc spinlock support.
+ *
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ */
+
+#ifndef __SPARC64_SPINLOCK_H
+#define __SPARC64_SPINLOCK_H
+
+#include <linux/config.h>
+#include <linux/threads.h>	/* For NR_CPUS */
+
+#ifndef __ASSEMBLY__
+
+/* To get debugging spinlocks which detect and catch
+ * deadlock situations, set CONFIG_DEBUG_SPINLOCK
+ * and rebuild your kernel.
+ */
+
+/* All of these locking primitives are expected to work properly
+ * even in an RMO memory model, which currently is what the kernel
+ * runs in.
+ *
+ * There is another issue.  Because we play games to save cycles
+ * in the non-contention case, we need to be extra careful about
+ * branch targets into the "spinning" code.  They live in their
+ * own section, but the newer V9 branches have a shorter range
+ * than the traditional 32-bit sparc branch variants.  The rule
+ * is that the branches that go into and out of the spinner sections
+ * must be pre-V9 branches.
+ */
+
+#ifndef CONFIG_DEBUG_SPINLOCK
+
+typedef unsigned char spinlock_t;
+#define SPIN_LOCK_UNLOCKED	0
+
+#define spin_lock_init(lock)	(*((unsigned char *)(lock)) = 0)
+#define spin_is_locked(lock)	(*((volatile unsigned char *)(lock)) != 0)
+
+#define spin_unlock_wait(lock)	\
+do {	membar("#LoadLoad");	\
+} while(*((volatile unsigned char *)lock))
+
+static inline void _raw_spin_lock(spinlock_t *lock)
+{
+	unsigned long tmp;
+
+	__asm__ __volatile__(
+"1:	ldstub		[%1], %0\n"
+"	brnz,pn		%0, 2f\n"
+"	 membar		#StoreLoad | #StoreStore\n"
+"	.subsection	2\n"
+"2:	ldub		[%1], %0\n"
+"	brnz,pt		%0, 2b\n"
+"	 membar		#LoadLoad\n"
+"	ba,a,pt		%%xcc, 1b\n"
+"	.previous"
+	: "=&r" (tmp)
+	: "r" (lock)
+	: "memory");
+}
+
+static inline int _raw_spin_trylock(spinlock_t *lock)
+{
+	unsigned long result;
+
+	__asm__ __volatile__(
+"	ldstub		[%1], %0\n"
+"	membar		#StoreLoad | #StoreStore"
+	: "=r" (result)
+	: "r" (lock)
+	: "memory");
+
+	return (result == 0UL);
+}
+
+static inline void _raw_spin_unlock(spinlock_t *lock)
+{
+	__asm__ __volatile__(
+"	membar		#StoreStore | #LoadStore\n"
+"	stb		%%g0, [%0]"
+	: /* No outputs */
+	: "r" (lock)
+	: "memory");
+}
+
+static inline void _raw_spin_lock_flags(spinlock_t *lock, unsigned long flags)
+{
+	unsigned long tmp1, tmp2;
+
+	__asm__ __volatile__(
+"1:	ldstub		[%2], %0\n"
+"	brnz,pn		%0, 2f\n"
+"	membar		#StoreLoad | #StoreStore\n"
+"	.subsection	2\n"
+"2:	rdpr		%%pil, %1\n"
+"	wrpr		%3, %%pil\n"
+"3:	ldub		[%2], %0\n"
+"	brnz,pt		%0, 3b\n"
+"	membar		#LoadLoad\n"
+"	ba,pt		%%xcc, 1b\n"
+"	wrpr		%1, %%pil\n"
+"	.previous"
+	: "=&r" (tmp1), "=&r" (tmp2)
+	: "r"(lock), "r"(flags)
+	: "memory");
+}
+
+#else /* !(CONFIG_DEBUG_SPINLOCK) */
+
+typedef struct {
+	unsigned char lock;
+	unsigned int owner_pc, owner_cpu;
+} spinlock_t;
+#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0, 0, 0xff }
+#define spin_lock_init(__lock)	\
+do {	(__lock)->lock = 0; \
+	(__lock)->owner_pc = 0; \
+	(__lock)->owner_cpu = 0xff; \
+} while(0)
+#define spin_is_locked(__lock)	(*((volatile unsigned char *)(&((__lock)->lock))) != 0)
+#define spin_unlock_wait(__lock)	\
+do { \
+	membar("#LoadLoad"); \
+} while(*((volatile unsigned char *)(&((__lock)->lock))))
+
+extern void _do_spin_lock (spinlock_t *lock, char *str);
+extern void _do_spin_unlock (spinlock_t *lock);
+extern int _do_spin_trylock (spinlock_t *lock);
+
+#define _raw_spin_trylock(lp)	_do_spin_trylock(lp)
+#define _raw_spin_lock(lock)	_do_spin_lock(lock, "spin_lock")
+#define _raw_spin_unlock(lock)	_do_spin_unlock(lock)
+#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
+
+#endif /* CONFIG_DEBUG_SPINLOCK */
+
+/* Multi-reader locks, these are much saner than the 32-bit Sparc ones... */
+
+#ifndef CONFIG_DEBUG_SPINLOCK
+
+typedef unsigned int rwlock_t;
+#define RW_LOCK_UNLOCKED	0
+#define rwlock_init(lp) do { *(lp) = RW_LOCK_UNLOCKED; } while(0)
+
+static void inline __read_lock(rwlock_t *lock)
+{
+	unsigned long tmp1, tmp2;
+
+	__asm__ __volatile__ (
+"1:	ldsw		[%2], %0\n"
+"	brlz,pn		%0, 2f\n"
+"4:	 add		%0, 1, %1\n"
+"	cas		[%2], %0, %1\n"
+"	cmp		%0, %1\n"
+"	bne,pn		%%icc, 1b\n"
+"	 membar		#StoreLoad | #StoreStore\n"
+"	.subsection	2\n"
+"2:	ldsw		[%2], %0\n"
+"	brlz,pt		%0, 2b\n"
+"	 membar		#LoadLoad\n"
+"	ba,a,pt		%%xcc, 4b\n"
+"	.previous"
+	: "=&r" (tmp1), "=&r" (tmp2)
+	: "r" (lock)
+	: "memory");
+}
+
+static void inline __read_unlock(rwlock_t *lock)
+{
+	unsigned long tmp1, tmp2;
+
+	__asm__ __volatile__(
+"	membar	#StoreLoad | #LoadLoad\n"
+"1:	lduw	[%2], %0\n"
+"	sub	%0, 1, %1\n"
+"	cas	[%2], %0, %1\n"
+"	cmp	%0, %1\n"
+"	bne,pn	%%xcc, 1b\n"
+"	 nop"
+	: "=&r" (tmp1), "=&r" (tmp2)
+	: "r" (lock)
+	: "memory");
+}
+
+static void inline __write_lock(rwlock_t *lock)
+{
+	unsigned long mask, tmp1, tmp2;
+
+	mask = 0x80000000UL;
+
+	__asm__ __volatile__(
+"1:	lduw		[%2], %0\n"
+"	brnz,pn		%0, 2f\n"
+"4:	 or		%0, %3, %1\n"
+"	cas		[%2], %0, %1\n"
+"	cmp		%0, %1\n"
+"	bne,pn		%%icc, 1b\n"
+"	 membar		#StoreLoad | #StoreStore\n"
+"	.subsection	2\n"
+"2:	lduw		[%2], %0\n"
+"	brnz,pt		%0, 2b\n"
+"	 membar		#LoadLoad\n"
+"	ba,a,pt		%%xcc, 4b\n"
+"	.previous"
+	: "=&r" (tmp1), "=&r" (tmp2)
+	: "r" (lock), "r" (mask)
+	: "memory");
+}
+
+static void inline __write_unlock(rwlock_t *lock)
+{
+	__asm__ __volatile__(
+"	membar		#LoadStore | #StoreStore\n"
+"	stw		%%g0, [%0]"
+	: /* no outputs */
+	: "r" (lock)
+	: "memory");
+}
+
+static int inline __write_trylock(rwlock_t *lock)
+{
+	unsigned long mask, tmp1, tmp2, result;
+
+	mask = 0x80000000UL;
+
+	__asm__ __volatile__(
+"	mov		0, %2\n"
+"1:	lduw		[%3], %0\n"
+"	brnz,pn		%0, 2f\n"
+"	 or		%0, %4, %1\n"
+"	cas		[%3], %0, %1\n"
+"	cmp		%0, %1\n"
+"	bne,pn		%%icc, 1b\n"
+"	 membar		#StoreLoad | #StoreStore\n"
+"	mov		1, %2\n"
+"2:"
+	: "=&r" (tmp1), "=&r" (tmp2), "=&r" (result)
+	: "r" (lock), "r" (mask)
+	: "memory");
+
+	return result;
+}
+
+#define _raw_read_lock(p)	__read_lock(p)
+#define _raw_read_unlock(p)	__read_unlock(p)
+#define _raw_write_lock(p)	__write_lock(p)
+#define _raw_write_unlock(p)	__write_unlock(p)
+#define _raw_write_trylock(p)	__write_trylock(p)
+
+#else /* !(CONFIG_DEBUG_SPINLOCK) */
+
+typedef struct {
+	unsigned long lock;
+	unsigned int writer_pc, writer_cpu;
+	unsigned int reader_pc[NR_CPUS];
+} rwlock_t;
+#define RW_LOCK_UNLOCKED	(rwlock_t) { 0, 0, 0xff, { } }
+#define rwlock_init(lp) do { *(lp) = RW_LOCK_UNLOCKED; } while(0)
+
+extern void _do_read_lock(rwlock_t *rw, char *str);
+extern void _do_read_unlock(rwlock_t *rw, char *str);
+extern void _do_write_lock(rwlock_t *rw, char *str);
+extern void _do_write_unlock(rwlock_t *rw);
+extern int _do_write_trylock(rwlock_t *rw, char *str);
+
+#define _raw_read_lock(lock) \
+do {	unsigned long flags; \
+	local_irq_save(flags); \
+	_do_read_lock(lock, "read_lock"); \
+	local_irq_restore(flags); \
+} while(0)
+
+#define _raw_read_unlock(lock) \
+do {	unsigned long flags; \
+	local_irq_save(flags); \
+	_do_read_unlock(lock, "read_unlock"); \
+	local_irq_restore(flags); \
+} while(0)
+
+#define _raw_write_lock(lock) \
+do {	unsigned long flags; \
+	local_irq_save(flags); \
+	_do_write_lock(lock, "write_lock"); \
+	local_irq_restore(flags); \
+} while(0)
+
+#define _raw_write_unlock(lock) \
+do {	unsigned long flags; \
+	local_irq_save(flags); \
+	_do_write_unlock(lock); \
+	local_irq_restore(flags); \
+} while(0)
+
+#define _raw_write_trylock(lock) \
+({	unsigned long flags; \
+	int val; \
+	local_irq_save(flags); \
+	val = _do_write_trylock(lock, "write_trylock"); \
+	local_irq_restore(flags); \
+	val; \
+})
+
+#endif /* CONFIG_DEBUG_SPINLOCK */
+
+#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
+
+#endif /* !(__ASSEMBLY__) */
+
+#endif /* !(__SPARC64_SPINLOCK_H) */