Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/include/asm-ppc/atomic.h b/include/asm-ppc/atomic.h
new file mode 100644
index 0000000..eeafd50
--- /dev/null
+++ b/include/asm-ppc/atomic.h
@@ -0,0 +1,214 @@
+/*
+ * PowerPC atomic operations
+ */
+
+#ifndef _ASM_PPC_ATOMIC_H_
+#define _ASM_PPC_ATOMIC_H_
+
+typedef struct { volatile int counter; } atomic_t;
+
+#ifdef __KERNEL__
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+extern void atomic_clear_mask(unsigned long mask, unsigned long *addr);
+
+#ifdef CONFIG_SMP
+#define SMP_SYNC "sync"
+#define SMP_ISYNC "\n\tisync"
+#else
+#define SMP_SYNC ""
+#define SMP_ISYNC
+#endif
+
+/* Erratum #77 on the 405 means we need a sync or dcbt before every stwcx.
+ * The old ATOMIC_SYNC_FIX covered some but not all of this.
+ */
+#ifdef CONFIG_IBM405_ERR77
+#define PPC405_ERR77(ra,rb) "dcbt " #ra "," #rb ";"
+#else
+#define PPC405_ERR77(ra,rb)
+#endif
+
+static __inline__ void atomic_add(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%3 # atomic_add\n\
+ add %0,%2,%0\n"
+ PPC405_ERR77(0,%3)
+" stwcx. %0,0,%3 \n\
+ bne- 1b"
+ : "=&r" (t), "=m" (v->counter)
+ : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "cc");
+}
+
+static __inline__ int atomic_add_return(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%2 # atomic_add_return\n\
+ add %0,%1,%0\n"
+ PPC405_ERR77(0,%2)
+" stwcx. %0,0,%2 \n\
+ bne- 1b"
+ SMP_ISYNC
+ : "=&r" (t)
+ : "r" (a), "r" (&v->counter)
+ : "cc", "memory");
+
+ return t;
+}
+
+#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
+
+static __inline__ void atomic_sub(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%3 # atomic_sub\n\
+ subf %0,%2,%0\n"
+ PPC405_ERR77(0,%3)
+" stwcx. %0,0,%3 \n\
+ bne- 1b"
+ : "=&r" (t), "=m" (v->counter)
+ : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "cc");
+}
+
+static __inline__ int atomic_sub_return(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%2 # atomic_sub_return\n\
+ subf %0,%1,%0\n"
+ PPC405_ERR77(0,%2)
+" stwcx. %0,0,%2 \n\
+ bne- 1b"
+ SMP_ISYNC
+ : "=&r" (t)
+ : "r" (a), "r" (&v->counter)
+ : "cc", "memory");
+
+ return t;
+}
+
+static __inline__ void atomic_inc(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%2 # atomic_inc\n\
+ addic %0,%0,1\n"
+ PPC405_ERR77(0,%2)
+" stwcx. %0,0,%2 \n\
+ bne- 1b"
+ : "=&r" (t), "=m" (v->counter)
+ : "r" (&v->counter), "m" (v->counter)
+ : "cc");
+}
+
+static __inline__ int atomic_inc_return(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%1 # atomic_inc_return\n\
+ addic %0,%0,1\n"
+ PPC405_ERR77(0,%1)
+" stwcx. %0,0,%1 \n\
+ bne- 1b"
+ SMP_ISYNC
+ : "=&r" (t)
+ : "r" (&v->counter)
+ : "cc", "memory");
+
+ return t;
+}
+
+/*
+ * 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)
+
+static __inline__ void atomic_dec(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%2 # atomic_dec\n\
+ addic %0,%0,-1\n"
+ PPC405_ERR77(0,%2)\
+" stwcx. %0,0,%2\n\
+ bne- 1b"
+ : "=&r" (t), "=m" (v->counter)
+ : "r" (&v->counter), "m" (v->counter)
+ : "cc");
+}
+
+static __inline__ int atomic_dec_return(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%1 # atomic_dec_return\n\
+ addic %0,%0,-1\n"
+ PPC405_ERR77(0,%1)
+" stwcx. %0,0,%1\n\
+ bne- 1b"
+ SMP_ISYNC
+ : "=&r" (t)
+ : "r" (&v->counter)
+ : "cc", "memory");
+
+ return t;
+}
+
+#define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
+#define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
+
+/*
+ * Atomically test *v and decrement if it is greater than 0.
+ * The function returns the old value of *v minus 1.
+ */
+static __inline__ int atomic_dec_if_positive(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__(
+"1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
+ addic. %0,%0,-1\n\
+ blt- 2f\n"
+ PPC405_ERR77(0,%1)
+" stwcx. %0,0,%1\n\
+ bne- 1b"
+ SMP_ISYNC
+ "\n\
+2:" : "=&r" (t)
+ : "r" (&v->counter)
+ : "cc", "memory");
+
+ return t;
+}
+
+#define __MB __asm__ __volatile__ (SMP_SYNC : : : "memory")
+#define smp_mb__before_atomic_dec() __MB
+#define smp_mb__after_atomic_dec() __MB
+#define smp_mb__before_atomic_inc() __MB
+#define smp_mb__after_atomic_inc() __MB
+
+#endif /* __KERNEL__ */
+#endif /* _ASM_PPC_ATOMIC_H_ */