sh: Split out atomic ops logically.

We have a few different ways to do the atomic operations, so split
them out in to different headers rather than bloating atomic.h.
Kernelspace gUSA will take this up to a third implementation.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/include/asm-sh/atomic-irq.h b/include/asm-sh/atomic-irq.h
new file mode 100644
index 00000000000..74f7943cff6
--- /dev/null
+++ b/include/asm-sh/atomic-irq.h
@@ -0,0 +1,71 @@
+#ifndef __ASM_SH_ATOMIC_IRQ_H
+#define __ASM_SH_ATOMIC_IRQ_H
+
+/*
+ * To get proper branch prediction for the main line, we must branch
+ * forward to code at the end of this object's .text section, then
+ * branch back to restart the operation.
+ */
+static inline void atomic_add(int i, atomic_t *v)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	*(long *)v += i;
+	local_irq_restore(flags);
+}
+
+static inline void atomic_sub(int i, atomic_t *v)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	*(long *)v -= i;
+	local_irq_restore(flags);
+}
+
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+	unsigned long temp, flags;
+
+	local_irq_save(flags);
+	temp = *(long *)v;
+	temp += i;
+	*(long *)v = temp;
+	local_irq_restore(flags);
+
+	return temp;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+	unsigned long temp, flags;
+
+	local_irq_save(flags);
+	temp = *(long *)v;
+	temp -= i;
+	*(long *)v = temp;
+	local_irq_restore(flags);
+
+	return temp;
+}
+
+static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	*(long *)v &= ~mask;
+	local_irq_restore(flags);
+}
+
+static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	*(long *)v |= mask;
+	local_irq_restore(flags);
+}
+
+#endif /* __ASM_SH_ATOMIC_IRQ_H */