[kernel] add linux-mips div64 rewrite to work with gcc-4.4.0 (#5023)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@15797 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 173 insertions, 0 deletions

diff --git a/target/linux/generic-2.6/patches-2.6.28/022-mips_div64_gcc4.4.0.patch b/target/linux/generic-2.6/patches-2.6.28/022-mips_div64_gcc4.4.0.patch
new file mode 100644
index 0000000000..a116cf437a
--- /dev/null
+++ b/target/linux/generic-2.6/patches-2.6.28/022-mips_div64_gcc4.4.0.patch
@@ -0,0 +1,173 @@
+From: Ralf Baechle <ralf@linux-mips.org>
+Date: Thu, 30 Apr 2009 16:14:56 +0000 (+0200)
+Subject: MIPS: Rewrite <asm/div64.h> to work with gcc 4.4.0.
+X-Git-Url: http://www.linux-mips.org/git?p=linux.git;a=commitdiff_plain;h=a1b68289997030df64cba8478d5767fe10e42a58
+
+MIPS: Rewrite <asm/div64.h> to work with gcc 4.4.0.
+
+The inline assembler used on 32-bit kernels was using the "h" constraint
+which was considered dangerous and removed for gcc 4.4.0.
+
+Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
+---
+
+diff --git a/arch/mips/include/asm/div64.h b/arch/mips/include/asm/div64.h
+index d1d6991..dc5ea57 100644
+--- a/arch/mips/include/asm/div64.h
++++ b/arch/mips/include/asm/div64.h
+@@ -6,105 +6,63 @@
+  * License.  See the file "COPYING" in the main directory of this archive
+  * for more details.
+  */
+-#ifndef _ASM_DIV64_H
+-#define _ASM_DIV64_H
++#ifndef __ASM_DIV64_H
++#define __ASM_DIV64_H
+ 
+-#include <linux/types.h>
++#include <asm-generic/div64.h>
+ 
+-#if (_MIPS_SZLONG == 32)
++#if BITS_PER_LONG == 64
+ 
+-#include <asm/compiler.h>
++#include <linux/types.h>
+ 
+ /*
+  * No traps on overflows for any of these...
+  */
+ 
+-#define do_div64_32(res, high, low, base) ({ \
+-	unsigned long __quot32, __mod32; \
+-	unsigned long __cf, __tmp, __tmp2, __i; \
+-	\
+-	__asm__(".set	push\n\t" \
+-		".set	noat\n\t" \
+-		".set	noreorder\n\t" \
+-		"move	%2, $0\n\t" \
+-		"move	%3, $0\n\t" \
+-		"b	1f\n\t" \
+-		" li	%4, 0x21\n" \
+-		"0:\n\t" \
+-		"sll	$1, %0, 0x1\n\t" \
+-		"srl	%3, %0, 0x1f\n\t" \
+-		"or	%0, $1, %5\n\t" \
+-		"sll	%1, %1, 0x1\n\t" \
+-		"sll	%2, %2, 0x1\n" \
+-		"1:\n\t" \
+-		"bnez	%3, 2f\n\t" \
+-		" sltu	%5, %0, %z6\n\t" \
+-		"bnez	%5, 3f\n" \
+-		"2:\n\t" \
+-		" addiu	%4, %4, -1\n\t" \
+-		"subu	%0, %0, %z6\n\t" \
+-		"addiu	%2, %2, 1\n" \
+-		"3:\n\t" \
+-		"bnez	%4, 0b\n\t" \
+-		" srl	%5, %1, 0x1f\n\t" \
+-		".set	pop" \
+-		: "=&r" (__mod32), "=&r" (__tmp), \
+-		  "=&r" (__quot32), "=&r" (__cf), \
+-		  "=&r" (__i), "=&r" (__tmp2) \
+-		: "Jr" (base), "0" (high), "1" (low)); \
+-	\
+-	(res) = __quot32; \
+-	__mod32; })
+-
+-#define do_div(n, base) ({ \
+-	unsigned long long __quot; \
+-	unsigned long __mod; \
+-	unsigned long long __div; \
+-	unsigned long __upper, __low, __high, __base; \
+-	\
+-	__div = (n); \
+-	__base = (base); \
+-	\
+-	__high = __div >> 32; \
+-	__low = __div; \
+-	__upper = __high; \
+-	\
+-	if (__high) \
+-		__asm__("divu	$0, %z2, %z3" \
+-			: "=h" (__upper), "=l" (__high) \
+-			: "Jr" (__high), "Jr" (__base) \
+-			: GCC_REG_ACCUM); \
+-	\
+-	__mod = do_div64_32(__low, __upper, __low, __base); \
+-	\
+-	__quot = __high; \
+-	__quot = __quot << 32 | __low; \
+-	(n) = __quot; \
+-	__mod; })
+-
+-#endif /* (_MIPS_SZLONG == 32) */
+-
+-#if (_MIPS_SZLONG == 64)
+-
+-/*
+- * Hey, we're already 64-bit, no
+- * need to play games..
+- */
+-#define do_div(n, base) ({ \
+-	unsigned long __quot; \
+-	unsigned int __mod; \
+-	unsigned long __div; \
+-	unsigned int __base; \
+-	\
+-	__div = (n); \
+-	__base = (base); \
+-	\
+-	__mod = __div % __base; \
+-	__quot = __div / __base; \
+-	\
+-	(n) = __quot; \
+-	__mod; })
++#define __div64_32(n, base)						\
++({									\
++	unsigned long __cf, __tmp, __tmp2, __i;				\
++	unsigned long __quot32, __mod32;				\
++	unsigned long __high, __low;					\
++	unsigned long long __n;						\
++									\
++	__high = *__n >> 32;						\
++	__low = __n;							\
++	__asm__(							\
++	"	.set	push					\n"	\
++	"	.set	noat					\n"	\
++	"	.set	noreorder				\n"	\
++	"	move	%2, $0					\n"	\
++	"	move	%3, $0					\n"	\
++	"	b	1f					\n"	\
++	"	 li	%4, 0x21				\n"	\
++	"0:							\n"	\
++	"	sll	$1, %0, 0x1				\n"	\
++	"	srl	%3, %0, 0x1f				\n"	\
++	"	or	%0, $1, %5				\n"	\
++	"	sll	%1, %1, 0x1				\n"	\
++	"	sll	%2, %2, 0x1				\n"	\
++	"1:							\n"	\
++	"	bnez	%3, 2f					\n"	\
++	"	 sltu	%5, %0, %z6				\n"	\
++	"	bnez	%5, 3f					\n"	\
++	"2:							\n"	\
++	"	 addiu	%4, %4, -1				\n"	\
++	"	subu	%0, %0, %z6				\n"	\
++	"	addiu	%2, %2, 1				\n"	\
++	"3:							\n"	\
++	"	bnez	%4, 0b\n\t"					\
++	"	 srl	%5, %1, 0x1f\n\t"				\
++	"	.set	pop"						\
++	: "=&r" (__mod32), "=&r" (__tmp),				\
++	  "=&r" (__quot32), "=&r" (__cf),				\
++	  "=&r" (__i), "=&r" (__tmp2)					\
++	: "Jr" (base), "0" (__high), "1" (__low));			\
++									\
++	(__n) = __quot32;						\
++	__mod32;							\
++})
+ 
+-#endif /* (_MIPS_SZLONG == 64) */
++#endif /* BITS_PER_LONG == 64 */
+ 
+-#endif /* _ASM_DIV64_H */
++#endif /* __ASM_DIV64_H */