[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, 0 insertions, 375 deletions

diff --git a/include/asm-ppc64/bitops.h b/include/asm-ppc64/bitops.h
deleted file mode 100644
index dbfa42ef4a9..00000000000
--- a/include/asm-ppc64/bitops.h
+++ /dev/null
@@ -1,360 +0,0 @@
-/*
- * PowerPC64 atomic bit operations.
- * Dave Engebretsen, Todd Inglett, Don Reed, Pat McCarthy, Peter Bergner,
- * Anton Blanchard
- *
- * Originally taken from the 32b PPC code.  Modified to use 64b values for
- * the various counters & memory references.
- *
- * Bitops are odd when viewed on big-endian systems.  They were designed
- * on little endian so the size of the bitset doesn't matter (low order bytes
- * come first) as long as the bit in question is valid.
- *
- * Bits are "tested" often using the C expression (val & (1<<nr)) so we do
- * our best to stay compatible with that.  The assumption is that val will
- * be unsigned long for such tests.  As such, we assume the bits are stored
- * as an array of unsigned long (the usual case is a single unsigned long,
- * of course).  Here's an example bitset with bit numbering:
- *
- *   |63..........0|127........64|195.......128|255.......196|
- *
- * This leads to a problem. If an int, short or char is passed as a bitset
- * it will be a bad memory reference since we want to store in chunks
- * of unsigned long (64 bits here) size.
- *
- * There are a few little-endian macros used mostly for filesystem bitmaps,
- * these work on similar bit arrays layouts, but byte-oriented:
- *
- *   |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
- *
- * The main difference is that bit 3-5 in the bit number field needs to be
- * reversed compared to the big-endian bit fields. This can be achieved
- * by XOR with 0b111000 (0x38).
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#ifndef _PPC64_BITOPS_H
-#define _PPC64_BITOPS_H
-
-#ifdef __KERNEL__
-
-#include <asm/synch.h>
-
-/*
- * clear_bit doesn't imply a memory barrier
- */
-#define smp_mb__before_clear_bit()	smp_mb()
-#define smp_mb__after_clear_bit()	smp_mb()
-
-static __inline__ int test_bit(unsigned long nr, __const__ volatile unsigned long *addr)
-{
-	return (1UL & (addr[nr >> 6] >> (nr & 63)));
-}
-
-static __inline__ void set_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-"1:	ldarx	%0,0,%3		# set_bit\n\
-	or	%0,%0,%2\n\
-	stdcx.	%0,0,%3\n\
-	bne-	1b"
-	: "=&r" (old), "=m" (*p)
-	: "r" (mask), "r" (p), "m" (*p)
-	: "cc");
-}
-
-static __inline__ void clear_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-"1:	ldarx	%0,0,%3		# clear_bit\n\
-	andc	%0,%0,%2\n\
-	stdcx.	%0,0,%3\n\
-	bne-	1b"
-	: "=&r" (old), "=m" (*p)
-	: "r" (mask), "r" (p), "m" (*p)
-	: "cc");
-}
-
-static __inline__ void change_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-"1:	ldarx	%0,0,%3		# change_bit\n\
-	xor	%0,%0,%2\n\
-	stdcx.	%0,0,%3\n\
-	bne-	1b"
-	: "=&r" (old), "=m" (*p)
-	: "r" (mask), "r" (p), "m" (*p)
-	: "cc");
-}
-
-static __inline__ int test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old, t;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-	EIEIO_ON_SMP
-"1:	ldarx	%0,0,%3		# test_and_set_bit\n\
-	or	%1,%0,%2 \n\
-	stdcx.	%1,0,%3 \n\
-	bne-	1b"
-	ISYNC_ON_SMP
-	: "=&r" (old), "=&r" (t)
-	: "r" (mask), "r" (p)
-	: "cc", "memory");
-
-	return (old & mask) != 0;
-}
-
-static __inline__ int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old, t;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-	EIEIO_ON_SMP
-"1:	ldarx	%0,0,%3		# test_and_clear_bit\n\
-	andc	%1,%0,%2\n\
-	stdcx.	%1,0,%3\n\
-	bne-	1b"
-	ISYNC_ON_SMP
-	: "=&r" (old), "=&r" (t)
-	: "r" (mask), "r" (p)
-	: "cc", "memory");
-
-	return (old & mask) != 0;
-}
-
-static __inline__ int test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long old, t;
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	__asm__ __volatile__(
-	EIEIO_ON_SMP
-"1:	ldarx	%0,0,%3		# test_and_change_bit\n\
-	xor	%1,%0,%2\n\
-	stdcx.	%1,0,%3\n\
-	bne-	1b"
-	ISYNC_ON_SMP
-	: "=&r" (old), "=&r" (t)
-	: "r" (mask), "r" (p)
-	: "cc", "memory");
-
-	return (old & mask) != 0;
-}
-
-static __inline__ void set_bits(unsigned long mask, unsigned long *addr)
-{
-	unsigned long old;
-
-	__asm__ __volatile__(
-"1:	ldarx	%0,0,%3		# set_bit\n\
-	or	%0,%0,%2\n\
-	stdcx.	%0,0,%3\n\
-	bne-	1b"
-	: "=&r" (old), "=m" (*addr)
-	: "r" (mask), "r" (addr), "m" (*addr)
-	: "cc");
-}
-
-/*
- * non-atomic versions
- */
-static __inline__ void __set_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	*p |= mask;
-}
-
-static __inline__ void __clear_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	*p &= ~mask;
-}
-
-static __inline__ void __change_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-
-	*p ^= mask;
-}
-
-static __inline__ int __test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-	unsigned long old = *p;
-
-	*p = old | mask;
-	return (old & mask) != 0;
-}
-
-static __inline__ int __test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-	unsigned long old = *p;
-
-	*p = old & ~mask;
-	return (old & mask) != 0;
-}
-
-static __inline__ int __test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
-{
-	unsigned long mask = 1UL << (nr & 0x3f);
-	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
-	unsigned long old = *p;
-
-	*p = old ^ mask;
-	return (old & mask) != 0;
-}
-
-/*
- * Return the zero-based bit position (from RIGHT TO LEFT, 63 -> 0) of the
- * most significant (left-most) 1-bit in a double word.
- */
-static __inline__ int __ilog2(unsigned long x)
-{
-	int lz;
-
-	asm ("cntlzd %0,%1" : "=r" (lz) : "r" (x));
-	return 63 - lz;
-}
-
-/*
- * Determines the bit position of the least significant (rightmost) 0 bit
- * in the specified double word. The returned bit position will be zero-based,
- * starting from the right side (63 - 0).
- */
-static __inline__ unsigned long ffz(unsigned long x)
-{
-	/* no zero exists anywhere in the 8 byte area. */
-	if ((x = ~x) == 0)
-		return 64;
-
-	/*
-	 * Calculate the bit position of the least signficant '1' bit in x
-	 * (since x has been changed this will actually be the least signficant
-	 * '0' bit in * the original x).  Note: (x & -x) gives us a mask that
-	 * is the least significant * (RIGHT-most) 1-bit of the value in x.
-	 */
-	return __ilog2(x & -x);
-}
-
-static __inline__ int __ffs(unsigned long x)
-{
-	return __ilog2(x & -x);
-}
-
-/*
- * ffs: find first bit set. This is defined the same way as
- * the libc and compiler builtin ffs routines, therefore
- * differs in spirit from the above ffz (man ffs).
- */
-static __inline__ int ffs(int x)
-{
-	unsigned long i = (unsigned long)x;
-	return __ilog2(i & -i) + 1;
-}
-
-/*
- * fls: find last (most-significant) bit set.
- * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
- */
-#define fls(x) generic_fls(x)
-
-/*
- * hweightN: returns the hamming weight (i.e. the number
- * of bits set) of a N-bit word
- */
-#define hweight64(x) generic_hweight64(x)
-#define hweight32(x) generic_hweight32(x)
-#define hweight16(x) generic_hweight16(x)
-#define hweight8(x) generic_hweight8(x)
-
-extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
-#define find_first_zero_bit(addr, size) \
-	find_next_zero_bit((addr), (size), 0)
-
-extern unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
-#define find_first_bit(addr, size) \
-	find_next_bit((addr), (size), 0)
-
-extern unsigned long find_next_zero_le_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
-#define find_first_zero_le_bit(addr, size) \
-	find_next_zero_le_bit((addr), (size), 0)
-
-static __inline__ int test_le_bit(unsigned long nr, __const__ unsigned long * addr)
-{
-	__const__ unsigned char	*ADDR = (__const__ unsigned char *) addr;
-	return (ADDR[nr >> 3] >> (nr & 7)) & 1;
-}
-
-#define test_and_clear_le_bit(nr, addr) \
-	test_and_clear_bit((nr) ^ 0x38, (addr))
-#define test_and_set_le_bit(nr, addr) \
-	test_and_set_bit((nr) ^ 0x38, (addr))
-
-/*
- * non-atomic versions
- */
-
-#define __set_le_bit(nr, addr) \
-	__set_bit((nr) ^ 0x38, (addr))
-#define __clear_le_bit(nr, addr) \
-	__clear_bit((nr) ^ 0x38, (addr))
-#define __test_and_clear_le_bit(nr, addr) \
-	__test_and_clear_bit((nr) ^ 0x38, (addr))
-#define __test_and_set_le_bit(nr, addr) \
-	__test_and_set_bit((nr) ^ 0x38, (addr))
-
-#define ext2_set_bit(nr,addr) \
-	__test_and_set_le_bit((nr), (unsigned long*)addr)
-#define ext2_clear_bit(nr, addr) \
-	__test_and_clear_le_bit((nr), (unsigned long*)addr)
-
-#define ext2_set_bit_atomic(lock, nr, addr) \
-	test_and_set_le_bit((nr), (unsigned long*)addr)
-#define ext2_clear_bit_atomic(lock, nr, addr) \
-	test_and_clear_le_bit((nr), (unsigned long*)addr)
-
-
-#define ext2_test_bit(nr, addr)      test_le_bit((nr),(unsigned long*)addr)
-#define ext2_find_first_zero_bit(addr, size) \
-	find_first_zero_le_bit((unsigned long*)addr, size)
-#define ext2_find_next_zero_bit(addr, size, off) \
-	find_next_zero_le_bit((unsigned long*)addr, size, off)
-
-#define minix_test_and_set_bit(nr,addr)		test_and_set_bit(nr,addr)
-#define minix_set_bit(nr,addr)			set_bit(nr,addr)
-#define minix_test_and_clear_bit(nr,addr)	test_and_clear_bit(nr,addr)
-#define minix_test_bit(nr,addr)			test_bit(nr,addr)
-#define minix_find_first_zero_bit(addr,size)	find_first_zero_bit(addr,size)
-
-#endif /* __KERNEL__ */
-#endif /* _PPC64_BITOPS_H */
diff --git a/include/asm-ppc64/mmu_context.h b/include/asm-ppc64/mmu_context.h
index 77a743402db..820dd729b89 100644
--- a/include/asm-ppc64/mmu_context.h
+++ b/include/asm-ppc64/mmu_context.h
@@ -16,21 +16,6 @@
  * 2 of the License, or (at your option) any later version.
  */
 
-/*
- * Every architecture must define this function. It's the fastest
- * way of searching a 140-bit bitmap where the first 100 bits are
- * unlikely to be set. It's guaranteed that at least one of the 140
- * bits is cleared.
- */
-static inline int sched_find_first_bit(unsigned long *b)
-{
-	if (unlikely(b[0]))
-		return __ffs(b[0]);
-	if (unlikely(b[1]))
-		return __ffs(b[1]) + 64;
-	return __ffs(b[2]) + 128;
-}
-
 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
 {
 }