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Subject[PATCH v2 28/44] metag: Atomics, locks and bitops
Date
Add header files to implement Meta hardware thread locks (used by some
other atomic operations), atomics, spinlocks, and bitops.

There are 2 main types of atomic primitives for metag (in addition to
IRQs off on UP):
- LOCK instructions provide locking between hardware threads.
- LNKGET/LNKSET instructions provide load-linked/store-conditional
operations allowing for lighter weight atomics on Meta2)

LOCK instructions allow for hardware threads to acquire voluntary or
exclusive hardware thread locks:
- LOCK0 releases exclusive and voluntary lock from the running hardware
thread.
- LOCK1 acquires the voluntary hardware lock, blocking until it becomes
available.
- LOCK2 implies LOCK1, and additionally acquires the exclusive hardware
lock, blocking all other hardware threads from executing.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
---
arch/metag/include/asm/atomic.h | 53 ++++++
arch/metag/include/asm/atomic_lnkget.h | 245 ++++++++++++++++++++++++++++
arch/metag/include/asm/atomic_lock1.h | 160 ++++++++++++++++++
arch/metag/include/asm/bitops.h | 132 +++++++++++++++
arch/metag/include/asm/cmpxchg.h | 65 ++++++++
arch/metag/include/asm/cmpxchg_irq.h | 42 +++++
arch/metag/include/asm/cmpxchg_lnkget.h | 86 ++++++++++
arch/metag/include/asm/cmpxchg_lock1.h | 48 ++++++
arch/metag/include/asm/lock.h | 14 ++
arch/metag/include/asm/spinlock.h | 22 +++
arch/metag/include/asm/spinlock_lnkget.h | 261 ++++++++++++++++++++++++++++++
arch/metag/include/asm/spinlock_lock1.h | 184 +++++++++++++++++++++
arch/metag/include/asm/spinlock_types.h | 20 +++
13 files changed, 1332 insertions(+), 0 deletions(-)
create mode 100644 arch/metag/include/asm/atomic.h
create mode 100644 arch/metag/include/asm/atomic_lnkget.h
create mode 100644 arch/metag/include/asm/atomic_lock1.h
create mode 100644 arch/metag/include/asm/bitops.h
create mode 100644 arch/metag/include/asm/cmpxchg.h
create mode 100644 arch/metag/include/asm/cmpxchg_irq.h
create mode 100644 arch/metag/include/asm/cmpxchg_lnkget.h
create mode 100644 arch/metag/include/asm/cmpxchg_lock1.h
create mode 100644 arch/metag/include/asm/lock.h
create mode 100644 arch/metag/include/asm/spinlock.h
create mode 100644 arch/metag/include/asm/spinlock_lnkget.h
create mode 100644 arch/metag/include/asm/spinlock_lock1.h
create mode 100644 arch/metag/include/asm/spinlock_types.h

diff --git a/arch/metag/include/asm/atomic.h b/arch/metag/include/asm/atomic.h
new file mode 100644
index 0000000..307ecd2
--- /dev/null
+++ b/arch/metag/include/asm/atomic.h
@@ -0,0 +1,53 @@
+#ifndef __ASM_METAG_ATOMIC_H
+#define __ASM_METAG_ATOMIC_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/cmpxchg.h>
+
+#if defined(CONFIG_METAG_ATOMICITY_IRQSOFF)
+/* The simple UP case. */
+#include <asm-generic/atomic.h>
+#else
+
+#if defined(CONFIG_METAG_ATOMICITY_LOCK1)
+#include <asm/atomic_lock1.h>
+#else
+#include <asm/atomic_lnkget.h>
+#endif
+
+#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
+
+#define atomic_dec_return(v) atomic_sub_return(1, (v))
+#define atomic_inc_return(v) atomic_add_return(1, (v))
+
+/*
+ * atomic_inc_and_test - increment and test
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
+
+#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
+
+#define atomic_inc(v) atomic_add(1, (v))
+#define atomic_dec(v) atomic_sub(1, (v))
+
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#endif
+
+#define atomic_dec_if_positive(v) atomic_sub_if_positive(1, v)
+
+#include <asm-generic/atomic64.h>
+
+#endif /* __ASM_METAG_ATOMIC_H */
diff --git a/arch/metag/include/asm/atomic_lnkget.h b/arch/metag/include/asm/atomic_lnkget.h
new file mode 100644
index 0000000..b05be05
--- /dev/null
+++ b/arch/metag/include/asm/atomic_lnkget.h
@@ -0,0 +1,245 @@
+#ifndef __ASM_METAG_ATOMIC_LNKGET_H
+#define __ASM_METAG_ATOMIC_LNKGET_H
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_set(v, i) ((v)->counter = (i))
+
+#include <linux/compiler.h>
+
+#include <asm/barrier.h>
+
+/*
+ * None of these asm statements clobber memory as LNKSET writes around
+ * the cache so the memory it modifies cannot safely be read by any means
+ * other than these accessors.
+ */
+
+static inline int atomic_read(const atomic_t *v)
+{
+ int temp;
+
+ __asm__ __volatile__(
+ "LNKGETD %0, [%1]\n"
+ : "=da" (temp)
+ : "da" (&v->counter)
+ );
+
+ return temp;
+}
+
+static inline void atomic_add(int i, atomic_t *v)
+{
+ int temp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0, [%1]\n"
+ " ADD %0, %0, %2\n"
+ " LNKSETD [%1], %0\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp)
+ : "da" (&v->counter), "bd" (i)
+ : "cc"
+ );
+}
+
+static inline void atomic_sub(int i, atomic_t *v)
+{
+ int temp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0, [%1]\n"
+ " SUB %0, %0, %2\n"
+ " LNKSETD [%1], %0\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp)
+ : "da" (&v->counter), "bd" (i)
+ : "cc"
+ );
+}
+
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+ int result, temp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " ADD %1, %1, %3\n"
+ " LNKSETD [%2], %1\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp), "=&da" (result)
+ : "da" (&v->counter), "bd" (i)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return result;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+ int result, temp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " SUB %1, %1, %3\n"
+ " LNKSETD [%2], %1\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp), "=&da" (result)
+ : "da" (&v->counter), "bd" (i)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return result;
+}
+
+static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
+{
+ int temp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0, [%1]\n"
+ " AND %0, %0, %2\n"
+ " LNKSETD [%1] %0\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp)
+ : "da" (&v->counter), "bd" (~mask)
+ : "cc"
+ );
+}
+
+static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
+{
+ int temp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0, [%1]\n"
+ " OR %0, %0, %2\n"
+ " LNKSETD [%1], %0\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp)
+ : "da" (&v->counter), "bd" (mask)
+ : "cc"
+ );
+}
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ int result, temp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " CMP %1, %3\n"
+ " LNKSETDEQ [%2], %4\n"
+ " BNE 2f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ "2:\n"
+ : "=&d" (temp), "=&d" (result)
+ : "da" (&v->counter), "bd" (old), "da" (new)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return result;
+}
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+ int temp, old;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " LNKSETD [%2], %3\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (temp), "=&d" (old)
+ : "da" (&v->counter), "da" (new)
+ : "cc"
+ );
+
+ return old;
+}
+
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int result, temp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " CMP %1, %3\n"
+ " ADD %0, %1, %4\n"
+ " LNKSETDNE [%2], %0\n"
+ " BEQ 2f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ "2:\n"
+ : "=&d" (temp), "=&d" (result)
+ : "da" (&v->counter), "bd" (u), "bd" (a)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return result;
+}
+
+static inline int atomic_sub_if_positive(int i, atomic_t *v)
+{
+ int result, temp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " SUBS %1, %1, %3\n"
+ " LNKSETDGE [%2], %1\n"
+ " BLT 2f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ "2:\n"
+ : "=&d" (temp), "=&da" (result)
+ : "da" (&v->counter), "bd" (i)
+ : "cc"
+ );
+
+ return result;
+}
+
+#endif /* __ASM_METAG_ATOMIC_LNKGET_H */
diff --git a/arch/metag/include/asm/atomic_lock1.h b/arch/metag/include/asm/atomic_lock1.h
new file mode 100644
index 0000000..0ce2a9d
--- /dev/null
+++ b/arch/metag/include/asm/atomic_lock1.h
@@ -0,0 +1,160 @@
+#ifndef __ASM_METAG_ATOMIC_LOCK1_H
+#define __ASM_METAG_ATOMIC_LOCK1_H
+
+#define ATOMIC_INIT(i) { (i) }
+
+#include <linux/compiler.h>
+
+#include <asm/barrier.h>
+#include <asm/lock.h>
+
+static inline int atomic_read(const atomic_t *v)
+{
+ return (v)->counter;
+}
+
+/*
+ * atomic_set needs to be take the lock to protect atomic_add_unless from a
+ * possible race, as it reads the counter twice:
+ *
+ * CPU0 CPU1
+ * atomic_add_unless(1, 0)
+ * ret = v->counter (non-zero)
+ * if (ret != u) v->counter = 0
+ * v->counter += 1 (counter set to 1)
+ *
+ * Making atomic_set take the lock ensures that ordering and logical
+ * consistency is preserved.
+ */
+static inline int atomic_set(atomic_t *v, int i)
+{
+ unsigned long flags;
+
+ __global_lock1(flags);
+ fence();
+ v->counter = i;
+ __global_unlock1(flags);
+ return i;
+}
+
+static inline void atomic_add(int i, atomic_t *v)
+{
+ unsigned long flags;
+
+ __global_lock1(flags);
+ fence();
+ v->counter += i;
+ __global_unlock1(flags);
+}
+
+static inline void atomic_sub(int i, atomic_t *v)
+{
+ unsigned long flags;
+
+ __global_lock1(flags);
+ fence();
+ v->counter -= i;
+ __global_unlock1(flags);
+}
+
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+ unsigned long result;
+ unsigned long flags;
+
+ __global_lock1(flags);
+ result = v->counter;
+ result += i;
+ fence();
+ v->counter = result;
+ __global_unlock1(flags);
+
+ return result;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+ unsigned long result;
+ unsigned long flags;
+
+ __global_lock1(flags);
+ result = v->counter;
+ result -= i;
+ fence();
+ v->counter = result;
+ __global_unlock1(flags);
+
+ return result;
+}
+
+static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
+{
+ unsigned long flags;
+
+ __global_lock1(flags);
+ fence();
+ v->counter &= ~mask;
+ __global_unlock1(flags);
+}
+
+static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
+{
+ unsigned long flags;
+
+ __global_lock1(flags);
+ fence();
+ v->counter |= mask;
+ __global_unlock1(flags);
+}
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ int ret;
+ unsigned long flags;
+
+ __global_lock1(flags);
+ ret = v->counter;
+ if (ret == old) {
+ fence();
+ v->counter = new;
+ }
+ __global_unlock1(flags);
+
+ return ret;
+}
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int ret;
+ unsigned long flags;
+
+ __global_lock1(flags);
+ ret = v->counter;
+ if (ret != u) {
+ fence();
+ v->counter += a;
+ }
+ __global_unlock1(flags);
+
+ return ret;
+}
+
+static inline int atomic_sub_if_positive(int i, atomic_t *v)
+{
+ int ret;
+ unsigned long flags;
+
+ __global_lock1(flags);
+ ret = v->counter - 1;
+ if (ret >= 0) {
+ fence();
+ v->counter = ret;
+ }
+ __global_unlock1(flags);
+
+ return ret;
+}
+
+#endif /* __ASM_METAG_ATOMIC_LOCK1_H */
diff --git a/arch/metag/include/asm/bitops.h b/arch/metag/include/asm/bitops.h
new file mode 100644
index 0000000..638a364
--- /dev/null
+++ b/arch/metag/include/asm/bitops.h
@@ -0,0 +1,132 @@
+#ifndef __ASM_METAG_BITOPS_H
+#define __ASM_METAG_BITOPS_H
+
+#include <linux/compiler.h>
+#include <asm/barrier.h>
+#include <asm/lock.h>
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+#ifdef CONFIG_SMP
+/*
+ * These functions are the basis of our bit ops.
+ */
+static inline void set_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ fence();
+ *p |= mask;
+ __global_unlock1(flags);
+}
+
+static inline void clear_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ fence();
+ *p &= ~mask;
+ __global_unlock1(flags);
+}
+
+static inline void change_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ fence();
+ *p ^= mask;
+ __global_unlock1(flags);
+}
+
+static inline int test_and_set_bit(unsigned int bit, volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long old;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ old = *p;
+ if (!(old & mask)) {
+ fence();
+ *p = old | mask;
+ }
+ __global_unlock1(flags);
+
+ return (old & mask) != 0;
+}
+
+static inline int test_and_clear_bit(unsigned int bit,
+ volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long old;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ old = *p;
+ if (old & mask) {
+ fence();
+ *p = old & ~mask;
+ }
+ __global_unlock1(flags);
+
+ return (old & mask) != 0;
+}
+
+static inline int test_and_change_bit(unsigned int bit,
+ volatile unsigned long *p)
+{
+ unsigned long flags;
+ unsigned long old;
+ unsigned long mask = 1UL << (bit & 31);
+
+ p += bit >> 5;
+
+ __global_lock1(flags);
+ fence();
+ old = *p;
+ *p = old ^ mask;
+ __global_unlock1(flags);
+
+ return (old & mask) != 0;
+}
+
+#else
+#include <asm-generic/bitops/atomic.h>
+#endif /* CONFIG_SMP */
+
+#include <asm-generic/bitops/non-atomic.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/ffs.h>
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+
+#endif /* __ASM_METAG_BITOPS_H */
diff --git a/arch/metag/include/asm/cmpxchg.h b/arch/metag/include/asm/cmpxchg.h
new file mode 100644
index 0000000..b1bc1be
--- /dev/null
+++ b/arch/metag/include/asm/cmpxchg.h
@@ -0,0 +1,65 @@
+#ifndef __ASM_METAG_CMPXCHG_H
+#define __ASM_METAG_CMPXCHG_H
+
+#include <asm/barrier.h>
+
+#if defined(CONFIG_METAG_ATOMICITY_IRQSOFF)
+#include <asm/cmpxchg_irq.h>
+#elif defined(CONFIG_METAG_ATOMICITY_LOCK1)
+#include <asm/cmpxchg_lock1.h>
+#elif defined(CONFIG_METAG_ATOMICITY_LNKGET)
+#include <asm/cmpxchg_lnkget.h>
+#endif
+
+extern void __xchg_called_with_bad_pointer(void);
+
+#define __xchg(ptr, x, size) \
+({ \
+ unsigned long __xchg__res; \
+ volatile void *__xchg_ptr = (ptr); \
+ switch (size) { \
+ case 4: \
+ __xchg__res = xchg_u32(__xchg_ptr, x); \
+ break; \
+ case 1: \
+ __xchg__res = xchg_u8(__xchg_ptr, x); \
+ break; \
+ default: \
+ __xchg_called_with_bad_pointer(); \
+ __xchg__res = x; \
+ break; \
+ } \
+ \
+ __xchg__res; \
+})
+
+#define xchg(ptr, x) \
+ ((__typeof__(*(ptr)))__xchg((ptr), (unsigned long)(x), sizeof(*(ptr))))
+
+/* This function doesn't exist, so you'll get a linker error
+ * if something tries to do an invalid cmpxchg(). */
+extern void __cmpxchg_called_with_bad_pointer(void);
+
+static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
+ unsigned long new, int size)
+{
+ switch (size) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+ }
+ __cmpxchg_called_with_bad_pointer();
+ return old;
+}
+
+#define __HAVE_ARCH_CMPXCHG 1
+
+#define cmpxchg(ptr, o, n) \
+ ({ \
+ __typeof__(*(ptr)) _o_ = (o); \
+ __typeof__(*(ptr)) _n_ = (n); \
+ (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
+ (unsigned long)_n_, \
+ sizeof(*(ptr))); \
+ })
+
+#endif /* __ASM_METAG_CMPXCHG_H */
diff --git a/arch/metag/include/asm/cmpxchg_irq.h b/arch/metag/include/asm/cmpxchg_irq.h
new file mode 100644
index 0000000..6495731
--- /dev/null
+++ b/arch/metag/include/asm/cmpxchg_irq.h
@@ -0,0 +1,42 @@
+#ifndef __ASM_METAG_CMPXCHG_IRQ_H
+#define __ASM_METAG_CMPXCHG_IRQ_H
+
+#include <linux/irqflags.h>
+
+static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ local_irq_save(flags);
+ retval = *m;
+ *m = val;
+ local_irq_restore(flags);
+ return retval;
+}
+
+static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ local_irq_save(flags);
+ retval = *m;
+ *m = val & 0xff;
+ local_irq_restore(flags);
+ return retval;
+}
+
+static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
+ unsigned long new)
+{
+ __u32 retval;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ retval = *m;
+ if (retval == old)
+ *m = new;
+ local_irq_restore(flags); /* implies memory barrier */
+ return retval;
+}
+
+#endif /* __ASM_METAG_CMPXCHG_IRQ_H */
diff --git a/arch/metag/include/asm/cmpxchg_lnkget.h b/arch/metag/include/asm/cmpxchg_lnkget.h
new file mode 100644
index 0000000..3a44b28
--- /dev/null
+++ b/arch/metag/include/asm/cmpxchg_lnkget.h
@@ -0,0 +1,86 @@
+#ifndef __ASM_METAG_CMPXCHG_LNKGET_H
+#define __ASM_METAG_CMPXCHG_LNKGET_H
+
+static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
+{
+ int temp, old;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " LNKSETD [%2], %3\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+#ifdef CONFIG_METAG_LNKGET_AROUND_CACHE
+ " DCACHE [%2], %0\n"
+#endif
+ : "=&d" (temp), "=&d" (old)
+ : "da" (m), "da" (val)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return old;
+}
+
+static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
+{
+ int temp, old;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " LNKSETD [%2], %3\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+#ifdef CONFIG_METAG_LNKGET_AROUND_CACHE
+ " DCACHE [%2], %0\n"
+#endif
+ : "=&d" (temp), "=&d" (old)
+ : "da" (m), "da" (val & 0xff)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return old;
+}
+
+static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
+ unsigned long new)
+{
+ __u32 retval, temp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %1, [%2]\n"
+ " CMP %1, %3\n"
+ " LNKSETDEQ [%2], %4\n"
+ " BNE 2f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+#ifdef CONFIG_METAG_LNKGET_AROUND_CACHE
+ " DCACHE [%2], %0\n"
+#endif
+ "2:\n"
+ : "=&d" (temp), "=&da" (retval)
+ : "da" (m), "bd" (old), "da" (new)
+ : "cc"
+ );
+
+ smp_mb();
+
+ return retval;
+}
+
+#endif /* __ASM_METAG_CMPXCHG_LNKGET_H */
diff --git a/arch/metag/include/asm/cmpxchg_lock1.h b/arch/metag/include/asm/cmpxchg_lock1.h
new file mode 100644
index 0000000..7fb4e1c
--- /dev/null
+++ b/arch/metag/include/asm/cmpxchg_lock1.h
@@ -0,0 +1,48 @@
+#ifndef __ASM_METAG_CMPXCHG_LOCK1_H
+#define __ASM_METAG_CMPXCHG_LOCK1_H
+
+#include <asm/lock.h>
+
+/* Use LOCK2 as these have to be atomic w.r.t. ordinary accesses. */
+
+static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ __global_lock2(flags);
+ fence();
+ retval = *m;
+ *m = val;
+ __global_unlock2(flags);
+ return retval;
+}
+
+static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ __global_lock2(flags);
+ fence();
+ retval = *m;
+ *m = val & 0xff;
+ __global_unlock2(flags);
+ return retval;
+}
+
+static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
+ unsigned long new)
+{
+ __u32 retval;
+ unsigned long flags;
+
+ __global_lock2(flags);
+ retval = *m;
+ if (retval == old) {
+ fence();
+ *m = new;
+ }
+ __global_unlock2(flags);
+ return retval;
+}
+
+#endif /* __ASM_METAG_CMPXCHG_LOCK1_H */
diff --git a/arch/metag/include/asm/lock.h b/arch/metag/include/asm/lock.h
new file mode 100644
index 0000000..360ca21
--- /dev/null
+++ b/arch/metag/include/asm/lock.h
@@ -0,0 +1,14 @@
+#ifndef __ASM_METAG_LOCK_H
+#define __ASM_METAG_LOCK_H
+
+#include <linux/compiler.h>
+
+#include <asm/tbx.h>
+
+#define __global_lock1(flags) { TBI_CRITON(flags); barrier(); }
+#define __global_unlock1(flags) { barrier(); TBI_CRITOFF(flags); }
+
+#define __global_lock2(flags) { TBI_LOCK(flags); barrier(); }
+#define __global_unlock2(flags) { barrier(); TBI_UNLOCK(flags); }
+
+#endif /* __ASM_METAG_LOCK_H */
diff --git a/arch/metag/include/asm/spinlock.h b/arch/metag/include/asm/spinlock.h
new file mode 100644
index 0000000..86a7cf3
--- /dev/null
+++ b/arch/metag/include/asm/spinlock.h
@@ -0,0 +1,22 @@
+#ifndef __ASM_SPINLOCK_H
+#define __ASM_SPINLOCK_H
+
+#ifdef CONFIG_METAG_ATOMICITY_LOCK1
+#include <asm/spinlock_lock1.h>
+#else
+#include <asm/spinlock_lnkget.h>
+#endif
+
+#define arch_spin_unlock_wait(lock) \
+ do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
+
+#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
+
+#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
+#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
+
+#define arch_spin_relax(lock) cpu_relax()
+#define arch_read_relax(lock) cpu_relax()
+#define arch_write_relax(lock) cpu_relax()
+
+#endif /* __ASM_SPINLOCK_H */
diff --git a/arch/metag/include/asm/spinlock_lnkget.h b/arch/metag/include/asm/spinlock_lnkget.h
new file mode 100644
index 0000000..0990e39
--- /dev/null
+++ b/arch/metag/include/asm/spinlock_lnkget.h
@@ -0,0 +1,261 @@
+#ifndef __ASM_SPINLOCK_LNKGET_H
+#define __ASM_SPINLOCK_LNKGET_H
+
+/*
+ * None of these asm statements clobber memory as LNKSET writes around
+ * the cache so the memory it modifies cannot safely be read by any means
+ * other than these accessors.
+ */
+
+static inline int arch_spin_is_locked(arch_spinlock_t *lock)
+{
+ int ret;
+
+ __asm__ __volatile__(
+ "LNKGETD %0, [%1]\n"
+ "TST %0, #1\n"
+ "MOV %0, #1\n"
+ "XORZ %0, %0, %0\n"
+ : "=&d" (ret)
+ : "da" (&lock->lock)
+ : "cc");
+ return ret;
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0,[%1]\n"
+ " TST %0, #1\n"
+ " ADD %0, %0, #1\n"
+ " LNKSETDZ [%1], %0\n"
+ " BNZ 1b\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (tmp)
+ : "da" (&lock->lock)
+ : "cc");
+
+ smp_mb();
+}
+
+/* Returns 0 if failed to acquire lock */
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ " LNKGETD %0,[%1]\n"
+ " TST %0, #1\n"
+ " ADD %0, %0, #1\n"
+ " LNKSETDZ [%1], %0\n"
+ " BNZ 1f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " MOV %0, #1\n"
+ "1: XORNZ %0, %0, %0\n"
+ : "=&d" (tmp)
+ : "da" (&lock->lock)
+ : "cc");
+
+ smp_mb();
+
+ return tmp;
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ smp_mb();
+
+ __asm__ __volatile__(
+ " SETD [%0], %1\n"
+ :
+ : "da" (&lock->lock), "da" (0)
+ : "memory");
+}
+
+/*
+ * RWLOCKS
+ *
+ *
+ * Write locks are easy - we just set bit 31. When unlocking, we can
+ * just write zero since the lock is exclusively held.
+ */
+
+static inline void arch_write_lock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0,[%1]\n"
+ " CMP %0, #0\n"
+ " ADD %0, %0, %2\n"
+ " LNKSETDZ [%1], %0\n"
+ " BNZ 1b\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock), "bd" (0x80000000)
+ : "cc");
+
+ smp_mb();
+}
+
+static inline int arch_write_trylock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ " LNKGETD %0,[%1]\n"
+ " CMP %0, #0\n"
+ " ADD %0, %0, %2\n"
+ " LNKSETDZ [%1], %0\n"
+ " BNZ 1f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " MOV %0,#1\n"
+ "1: XORNZ %0, %0, %0\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock), "bd" (0x80000000)
+ : "cc");
+
+ smp_mb();
+
+ return tmp;
+}
+
+static inline void arch_write_unlock(arch_rwlock_t *rw)
+{
+ smp_mb();
+
+ __asm__ __volatile__(
+ " SETD [%0], %1\n"
+ :
+ : "da" (&rw->lock), "da" (0)
+ : "memory");
+}
+
+/* write_can_lock - would write_trylock() succeed? */
+static inline int arch_write_can_lock(arch_rwlock_t *rw)
+{
+ int ret;
+
+ __asm__ __volatile__(
+ "LNKGETD %0, [%1]\n"
+ "CMP %0, #0\n"
+ "MOV %0, #1\n"
+ "XORNZ %0, %0, %0\n"
+ : "=&d" (ret)
+ : "da" (&rw->lock)
+ : "cc");
+ return ret;
+}
+
+/*
+ * Read locks are a bit more hairy:
+ * - Exclusively load the lock value.
+ * - Increment it.
+ * - Store new lock value if positive, and we still own this location.
+ * If the value is negative, we've already failed.
+ * - If we failed to store the value, we want a negative result.
+ * - If we failed, try again.
+ * Unlocking is similarly hairy. We may have multiple read locks
+ * currently active. However, we know we won't have any write
+ * locks.
+ */
+static inline void arch_read_lock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0,[%1]\n"
+ " ADDS %0, %0, #1\n"
+ " LNKSETDPL [%1], %0\n"
+ " BMI 1b\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock)
+ : "cc");
+
+ smp_mb();
+}
+
+static inline void arch_read_unlock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ smp_mb();
+
+ __asm__ __volatile__(
+ "1: LNKGETD %0,[%1]\n"
+ " SUB %0, %0, #1\n"
+ " LNKSETD [%1], %0\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " BNZ 1b\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock)
+ : "cc", "memory");
+}
+
+static inline int arch_read_trylock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ " LNKGETD %0,[%1]\n"
+ " ADDS %0, %0, #1\n"
+ " LNKSETDPL [%1], %0\n"
+ " BMI 1f\n"
+ " DEFR %0, TXSTAT\n"
+ " ANDT %0, %0, #HI(0x3f000000)\n"
+ " CMPT %0, #HI(0x02000000)\n"
+ " MOV %0,#1\n"
+ " BZ 2f\n"
+ "1: MOV %0,#0\n"
+ "2:\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock)
+ : "cc");
+
+ smp_mb();
+
+ return tmp;
+}
+
+/* read_can_lock - would read_trylock() succeed? */
+static inline int arch_read_can_lock(arch_rwlock_t *rw)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "LNKGETD %0, [%1]\n"
+ "CMP %0, %2\n"
+ "MOV %0, #1\n"
+ "XORZ %0, %0, %0\n"
+ : "=&d" (tmp)
+ : "da" (&rw->lock), "bd" (0x80000000)
+ : "cc");
+ return tmp;
+}
+
+#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
+#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
+
+#define arch_spin_relax(lock) cpu_relax()
+#define arch_read_relax(lock) cpu_relax()
+#define arch_write_relax(lock) cpu_relax()
+
+#endif /* __ASM_SPINLOCK_LNKGET_H */
diff --git a/arch/metag/include/asm/spinlock_lock1.h b/arch/metag/include/asm/spinlock_lock1.h
new file mode 100644
index 0000000..e9f27df
--- /dev/null
+++ b/arch/metag/include/asm/spinlock_lock1.h
@@ -0,0 +1,184 @@
+#ifndef __ASM_SPINLOCK_LOCK1_H
+#define __ASM_SPINLOCK_LOCK1_H
+
+#include <asm/bug.h>
+#include <asm/lock.h>
+
+static inline int arch_spin_is_locked(arch_spinlock_t *lock)
+{
+ int ret;
+
+ barrier();
+ ret = lock->lock;
+ WARN_ON(ret != 0 && ret != 1);
+ return ret;
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ unsigned int we_won = 0;
+ unsigned long flags;
+
+again:
+ __global_lock1(flags);
+ if (lock->lock == 0) {
+ fence();
+ lock->lock = 1;
+ we_won = 1;
+ }
+ __global_unlock1(flags);
+ if (we_won == 0)
+ goto again;
+ WARN_ON(lock->lock != 1);
+}
+
+/* Returns 0 if failed to acquire lock */
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ unsigned long flags;
+ unsigned int ret;
+
+ __global_lock1(flags);
+ ret = lock->lock;
+ if (ret == 0) {
+ fence();
+ lock->lock = 1;
+ }
+ __global_unlock1(flags);
+ return (ret == 0);
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ barrier();
+ WARN_ON(!lock->lock);
+ lock->lock = 0;
+}
+
+/*
+ * RWLOCKS
+ *
+ *
+ * Write locks are easy - we just set bit 31. When unlocking, we can
+ * just write zero since the lock is exclusively held.
+ */
+
+static inline void arch_write_lock(arch_rwlock_t *rw)
+{
+ unsigned long flags;
+ unsigned int we_won = 0;
+
+again:
+ __global_lock1(flags);
+ if (rw->lock == 0) {
+ fence();
+ rw->lock = 0x80000000;
+ we_won = 1;
+ }
+ __global_unlock1(flags);
+ if (we_won == 0)
+ goto again;
+ WARN_ON(rw->lock != 0x80000000);
+}
+
+static inline int arch_write_trylock(arch_rwlock_t *rw)
+{
+ unsigned long flags;
+ unsigned int ret;
+
+ __global_lock1(flags);
+ ret = rw->lock;
+ if (ret == 0) {
+ fence();
+ rw->lock = 0x80000000;
+ }
+ __global_unlock1(flags);
+
+ return (ret == 0);
+}
+
+static inline void arch_write_unlock(arch_rwlock_t *rw)
+{
+ barrier();
+ WARN_ON(rw->lock != 0x80000000);
+ rw->lock = 0;
+}
+
+/* write_can_lock - would write_trylock() succeed? */
+static inline int arch_write_can_lock(arch_rwlock_t *rw)
+{
+ unsigned int ret;
+
+ barrier();
+ ret = rw->lock;
+ return (ret == 0);
+}
+
+/*
+ * Read locks are a bit more hairy:
+ * - Exclusively load the lock value.
+ * - Increment it.
+ * - Store new lock value if positive, and we still own this location.
+ * If the value is negative, we've already failed.
+ * - If we failed to store the value, we want a negative result.
+ * - If we failed, try again.
+ * Unlocking is similarly hairy. We may have multiple read locks
+ * currently active. However, we know we won't have any write
+ * locks.
+ */
+static inline void arch_read_lock(arch_rwlock_t *rw)
+{
+ unsigned long flags;
+ unsigned int we_won = 0, ret;
+
+again:
+ __global_lock1(flags);
+ ret = rw->lock;
+ if (ret < 0x80000000) {
+ fence();
+ rw->lock = ret + 1;
+ we_won = 1;
+ }
+ __global_unlock1(flags);
+ if (!we_won)
+ goto again;
+}
+
+static inline void arch_read_unlock(arch_rwlock_t *rw)
+{
+ unsigned long flags;
+ unsigned int ret;
+
+ __global_lock1(flags);
+ fence();
+ ret = rw->lock--;
+ __global_unlock1(flags);
+ WARN_ON(ret == 0);
+}
+
+static inline int arch_read_trylock(arch_rwlock_t *rw)
+{
+ unsigned long flags;
+ unsigned int ret;
+
+ __global_lock1(flags);
+ ret = rw->lock;
+ if (ret < 0x80000000) {
+ fence();
+ rw->lock = ret + 1;
+ }
+ __global_unlock1(flags);
+ return (ret < 0x80000000);
+}
+
+/* read_can_lock - would read_trylock() succeed? */
+static inline int arch_read_can_lock(arch_rwlock_t *rw)
+{
+ unsigned int ret;
+
+ barrier();
+ ret = rw->lock;
+ return (ret < 0x80000000);
+}
+
+#endif /* __ASM_SPINLOCK_LOCK1_H */
diff --git a/arch/metag/include/asm/spinlock_types.h b/arch/metag/include/asm/spinlock_types.h
new file mode 100644
index 0000000..b763914
--- /dev/null
+++ b/arch/metag/include/asm/spinlock_types.h
@@ -0,0 +1,20 @@
+#ifndef _ASM_METAG_SPINLOCK_TYPES_H
+#define _ASM_METAG_SPINLOCK_TYPES_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+# error "please don't include this file directly"
+#endif
+
+typedef struct {
+ volatile unsigned int lock;
+} arch_spinlock_t;
+
+#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+
+typedef struct {
+ volatile unsigned int lock;
+} arch_rwlock_t;
+
+#define __ARCH_RW_LOCK_UNLOCKED { 0 }
+
+#endif /* _ASM_METAG_SPINLOCK_TYPES_H */
--
1.7.7.6



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