[PATCH] powerpc: Merge bitops.h

Here's a revised version.  This re-introduces the set_bits() function
from ppc64, which I removed because I thought it was unused (it exists
on no other arch).  In fact it is used in the powermac interrupt code
(but not on pSeries).

- We use LARXL/STCXL macros to generate the right (32 or 64 bit)
  instructions, similar to LDL/STL from ppc_asm.h, used in fpu.S

- ppc32 previously used a full "sync" barrier at the end of
  test_and_*_bit(), whereas ppc64 used an "isync".  The merged version
  uses "isync", since I believe that's sufficient.

- The ppc64 versions of then minix_*() bitmap functions have changed
  semantics.  Previously on ppc64, these functions were big-endian
  (that is bit 0 was the LSB in the first 64-bit, big-endian word).
  On ppc32 (and x86, for that matter, they were little-endian.  As far
  as I can tell, the big-endian usage was simply wrong - I guess
  no-one ever tried to use minixfs on ppc64.

- On ppc32 find_next_bit() and find_next_zero_bit() are no longer
  inline (they were already out-of-line on ppc64).

- For ppc64, sched_find_first_bit() has moved from mmu_context.h to
  the merged bitops.  What it was doing in mmu_context.h in the first
  place, I have no idea.

- The fls() function is now implemented using the cntlzw instruction
  on ppc64, instead of generic_fls(), as it already was on ppc32.

- For ARCH=ppc, this patch requires adding arch/powerpc/lib to the
  arch/ppc/Makefile.  This in turn requires some changes to
  arch/powerpc/lib/Makefile which didn't correctly handle ARCH=ppc.

Built and running on G5.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 1 insertions, 148 deletions

diff --git a/arch/ppc64/kernel/Makefile b/arch/ppc64/kernel/Makefile
index 247d2fc6a8e..990df0905c8 100644
--- a/arch/ppc64/kernel/Makefile
+++ b/arch/ppc64/kernel/Makefile
@@ -13,7 +13,7 @@ endif
 
 obj-y               +=	irq.o idle.o dma.o \
 			signal.o \
-			align.o bitops.o pacaData.o \
+			align.o pacaData.o \
 			udbg.o ioctl32.o \
 			rtc.o \
 			cpu_setup_power4.o \
diff --git a/arch/ppc64/kernel/bitops.c b/arch/ppc64/kernel/bitops.c
deleted file mode 100644
index ae329e8b4ac..00000000000
--- a/arch/ppc64/kernel/bitops.c
+++ /dev/null
@@ -1,147 +0,0 @@
-/*
- * These are too big to be inlined.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/bitops.h>
-#include <asm/byteorder.h>
-
-unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
-				 unsigned long offset)
-{
-	const unsigned long *p = addr + (offset >> 6);
-	unsigned long result = offset & ~63UL;
-	unsigned long tmp;
-
-	if (offset >= size)
-		return size;
-	size -= result;
-	offset &= 63UL;
-	if (offset) {
-		tmp = *(p++);
-		tmp |= ~0UL >> (64 - offset);
-		if (size < 64)
-			goto found_first;
-		if (~tmp)
-			goto found_middle;
-		size -= 64;
-		result += 64;
-	}
-	while (size & ~63UL) {
-		if (~(tmp = *(p++)))
-			goto found_middle;
-		result += 64;
-		size -= 64;
-	}
-	if (!size)
-		return result;
-	tmp = *p;
-
-found_first:
-	tmp |= ~0UL << size;
-	if (tmp == ~0UL)	/* Are any bits zero? */
-		return result + size;	/* Nope. */
-found_middle:
-	return result + ffz(tmp);
-}
-
-EXPORT_SYMBOL(find_next_zero_bit);
-
-unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
-			    unsigned long offset)
-{
-	const unsigned long *p = addr + (offset >> 6);
-	unsigned long result = offset & ~63UL;
-	unsigned long tmp;
-
-	if (offset >= size)
-		return size;
-	size -= result;
-	offset &= 63UL;
-	if (offset) {
-		tmp = *(p++);
-		tmp &= (~0UL << offset);
-		if (size < 64)
-			goto found_first;
-		if (tmp)
-			goto found_middle;
-		size -= 64;
-		result += 64;
-	}
-	while (size & ~63UL) {
-		if ((tmp = *(p++)))
-			goto found_middle;
-		result += 64;
-		size -= 64;
-	}
-	if (!size)
-		return result;
-	tmp = *p;
-
-found_first:
-	tmp &= (~0UL >> (64 - size));
-	if (tmp == 0UL)		/* Are any bits set? */
-		return result + size;	/* Nope. */
-found_middle:
-	return result + __ffs(tmp);
-}
-
-EXPORT_SYMBOL(find_next_bit);
-
-static inline unsigned int ext2_ilog2(unsigned int x)
-{
-	int lz;
-
-	asm("cntlzw %0,%1": "=r"(lz):"r"(x));
-	return 31 - lz;
-}
-
-static inline unsigned int ext2_ffz(unsigned int x)
-{
-	u32 rc;
-	if ((x = ~x) == 0)
-		return 32;
-	rc = ext2_ilog2(x & -x);
-	return rc;
-}
-
-unsigned long find_next_zero_le_bit(const unsigned long *addr, unsigned long size,
-				    unsigned long offset)
-{
-	const unsigned int *p = ((const unsigned int *)addr) + (offset >> 5);
-	unsigned int result = offset & ~31;
-	unsigned int tmp;
-
-	if (offset >= size)
-		return size;
-	size -= result;
-	offset &= 31;
-	if (offset) {
-		tmp = cpu_to_le32p(p++);
-		tmp |= ~0U >> (32 - offset);	/* bug or feature ? */
-		if (size < 32)
-			goto found_first;
-		if (tmp != ~0)
-			goto found_middle;
-		size -= 32;
-		result += 32;
-	}
-	while (size >= 32) {
-		if ((tmp = cpu_to_le32p(p++)) != ~0)
-			goto found_middle;
-		result += 32;
-		size -= 32;
-	}
-	if (!size)
-		return result;
-	tmp = cpu_to_le32p(p);
-found_first:
-	tmp |= ~0 << size;
-	if (tmp == ~0)		/* Are any bits zero? */
-		return result + size;	/* Nope. */
-found_middle:
-	return result + ext2_ffz(tmp);
-}
-
-EXPORT_SYMBOL(find_next_zero_le_bit);