Commit e08d703c authored by Greg Ungerer's avatar Greg Ungerer
Browse files

m68k: modify user space access functions to support ColdFire CPUs 



Modify the user space access functions to support the ColdFire V4e cores
running with MMU enabled.

The ColdFire processors do not support the "moves" instruction used by
the traditional 680x0 processors for moving data into and out of another
address space. They only support the notion of a single address space,
and you use the usual "move" instruction to access that.

Create a new config symbol (CONFIG_CPU_HAS_ADDRESS_SPACES) to mark the
CPU types that support separate address spaces, and thus also support
the sfc/dfc registers and the "moves" instruction that go along with that.

The code is almost identical for user space access, so lets just use a
define to choose either the "move" or "moves" in the assembler code.

Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.org>
Acked-by: default avatarMatt Waddel <mwaddel@yahoo.com>
Acked-by: default avatarKurt Mahan <kmahan@xmission.com>
Acked-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
parent 2c9b82ad

arch/m68k/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -66,6 +66,9 @@ config CPU_HAS_NO_BITFIELDS 
config CPU_HAS_NO_MULDIV64

	bool



config CPU_HAS_ADDRESS_SPACES

	bool



config HZ

	int

	default 1000 if CLEOPATRA

arch/m68k/Kconfig.cpu

+4 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ config M68020 
	bool "68020 support"

	depends on MMU

	select GENERIC_ATOMIC64

	select CPU_HAS_ADDRESS_SPACES

	help

	  If you anticipate running this kernel on a computer with a MC68020

	  processor, say Y. Otherwise, say N. Note that the 68020 requires a
@@ -48,6 +49,7 @@ config M68030 
	bool "68030 support"

	depends on MMU && !MMU_SUN3

	select GENERIC_ATOMIC64

	select CPU_HAS_ADDRESS_SPACES

	help

	  If you anticipate running this kernel on a computer with a MC68030

	  processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
@@ -57,6 +59,7 @@ config M68040 
	bool "68040 support"

	depends on MMU && !MMU_SUN3

	select GENERIC_ATOMIC64

	select CPU_HAS_ADDRESS_SPACES

	help

	  If you anticipate running this kernel on a computer with a MC68LC040

	  or MC68040 processor, say Y. Otherwise, say N. Note that an
@@ -67,6 +70,7 @@ config M68060 
	bool "68060 support"

	depends on MMU && !MMU_SUN3

	select GENERIC_ATOMIC64

	select CPU_HAS_ADDRESS_SPACES

	help

	  If you anticipate running this kernel on a computer with a MC68060

	  processor, say Y. Otherwise, say N.

arch/m68k/include/asm/segment.h

+2 −2
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ typedef struct { 


static inline mm_segment_t get_fs(void)

{

#ifdef CONFIG_MMU

#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES

	mm_segment_t _v;

	__asm__ ("movec %/dfc,%0":"=r" (_v.seg):);
@@ -49,7 +49,7 @@ static inline mm_segment_t get_ds(void) 


static inline void set_fs(mm_segment_t val)

{

#ifdef CONFIG_MMU

#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES

	__asm__ __volatile__ ("movec %0,%/sfc\n\t"

			      "movec %0,%/dfc\n\t"

			      : /* no outputs */ : "r" (val.seg) : "memory");

arch/m68k/include/asm/uaccess_mm.h

+29 −13
Original line number Diff line number Diff line
@@ -20,6 +20,22 @@ static inline int access_ok(int type, const void __user *addr, 
	return 1;

}



/*

 * Not all varients of the 68k family support the notion of address spaces.

 * The traditional 680x0 parts do, and they use the sfc/dfc registers and

 * the "moves" instruction to access user space from kernel space. Other

 * family members like ColdFire don't support this, and only have a single

 * address space, and use the usual "move" instruction for user space access.

 *

 * Outside of this difference the user space access functions are the same.

 * So lets keep the code simple and just define in what we need to use.

 */

#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES

#define	MOVES	"moves"

#else

#define	MOVES	"move"

#endif



/*

 * The exception table consists of pairs of addresses: the first is the

 * address of an instruction that is allowed to fault, and the second is
@@ -43,7 +59,7 @@ extern int __get_user_bad(void); 


#define __put_user_asm(res, x, ptr, bwl, reg, err)	\

asm volatile ("\n"					\

	"1:	moves."#bwl"	%2,%1\n"		\

	"1:	"MOVES"."#bwl"	%2,%1\n"		\

	"2:\n"						\

	"	.section .fixup,\"ax\"\n"		\

	"	.even\n"				\
@@ -83,8 +99,8 @@ asm volatile ("\n" \ 
 	    {								\

 		const void __user *__pu_ptr = (ptr);			\

		asm volatile ("\n"					\

			"1:	moves.l	%2,(%1)+\n"			\

			"2:	moves.l	%R2,(%1)\n"			\

			"1:	"MOVES".l	%2,(%1)+\n"		\

			"2:	"MOVES".l	%R2,(%1)\n"		\

			"3:\n"						\

			"	.section .fixup,\"ax\"\n"		\

			"	.even\n"				\
@@ -115,12 +131,12 @@ asm volatile ("\n" \ 
#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({	\

	type __gu_val;						\

	asm volatile ("\n"					\

		"1:	moves."#bwl"	%2,%1\n"		\

		"1:	"MOVES"."#bwl"	%2,%1\n"		\

		"2:\n"						\

		"	.section .fixup,\"ax\"\n"		\

		"	.even\n"				\

		"10:	move.l	%3,%0\n"			\

		"	sub."#bwl"	%1,%1\n"		\

		"	sub.l	%1,%1\n"			\

		"	jra	2b\n"				\

		"	.previous\n"				\

		"\n"						\
@@ -152,8 +168,8 @@ asm volatile ("\n" \ 
 		const void *__gu_ptr = (ptr);				\

 		u64 __gu_val;						\

		asm volatile ("\n"					\

			"1:	moves.l	(%2)+,%1\n"			\

			"2:	moves.l	(%2),%R1\n"			\

			"1:	"MOVES".l	(%2)+,%1\n"		\

			"2:	"MOVES".l	(%2),%R1\n"		\

			"3:\n"						\

			"	.section .fixup,\"ax\"\n"		\

			"	.even\n"				\
@@ -188,12 +204,12 @@ unsigned long __generic_copy_to_user(void __user *to, const void *from, unsigned 


#define __constant_copy_from_user_asm(res, to, from, tmp, n, s1, s2, s3)\

	asm volatile ("\n"						\

		"1:	moves."#s1"	(%2)+,%3\n"			\

		"1:	"MOVES"."#s1"	(%2)+,%3\n"			\

		"	move."#s1"	%3,(%1)+\n"			\

		"2:	moves."#s2"	(%2)+,%3\n"			\

		"2:	"MOVES"."#s2"	(%2)+,%3\n"			\

		"	move."#s2"	%3,(%1)+\n"			\

		"	.ifnc	\""#s3"\",\"\"\n"			\

		"3:	moves."#s3"	(%2)+,%3\n"			\

		"3:	"MOVES"."#s3"	(%2)+,%3\n"			\

		"	move."#s3"	%3,(%1)+\n"			\

		"	.endif\n"					\

		"4:\n"							\
@@ -269,13 +285,13 @@ __constant_copy_from_user(void *to, const void __user *from, unsigned long n) 
#define __constant_copy_to_user_asm(res, to, from, tmp, n, s1, s2, s3)	\

	asm volatile ("\n"						\

		"	move."#s1"	(%2)+,%3\n"			\

		"11:	moves."#s1"	%3,(%1)+\n"			\

		"11:	"MOVES"."#s1"	%3,(%1)+\n"			\

		"12:	move."#s2"	(%2)+,%3\n"			\

		"21:	moves."#s2"	%3,(%1)+\n"			\

		"21:	"MOVES"."#s2"	%3,(%1)+\n"			\

		"22:\n"							\

		"	.ifnc	\""#s3"\",\"\"\n"			\

		"	move."#s3"	(%2)+,%3\n"			\

		"31:	moves."#s3"	%3,(%1)+\n"			\

		"31:	"MOVES"."#s3"	%3,(%1)+\n"			\

		"32:\n"							\

		"	.endif\n"					\

		"4:\n"							\

arch/m68k/lib/uaccess.c

+11 −11
Original line number Diff line number Diff line
@@ -15,17 +15,17 @@ unsigned long __generic_copy_from_user(void *to, const void __user *from, 
	asm volatile ("\n"

		"	tst.l	%0\n"

		"	jeq	2f\n"

		"1:	moves.l	(%1)+,%3\n"

		"1:	"MOVES".l	(%1)+,%3\n"

		"	move.l	%3,(%2)+\n"

		"	subq.l	#1,%0\n"

		"	jne	1b\n"

		"2:	btst	#1,%5\n"

		"	jeq	4f\n"

		"3:	moves.w	(%1)+,%3\n"

		"3:	"MOVES".w	(%1)+,%3\n"

		"	move.w	%3,(%2)+\n"

		"4:	btst	#0,%5\n"

		"	jeq	6f\n"

		"5:	moves.b	(%1)+,%3\n"

		"5:	"MOVES".b	(%1)+,%3\n"

		"	move.b  %3,(%2)+\n"

		"6:\n"

		"	.section .fixup,\"ax\"\n"
@@ -68,17 +68,17 @@ unsigned long __generic_copy_to_user(void __user *to, const void *from, 
		"	tst.l	%0\n"

		"	jeq	4f\n"

		"1:	move.l	(%1)+,%3\n"

		"2:	moves.l	%3,(%2)+\n"

		"2:	"MOVES".l	%3,(%2)+\n"

		"3:	subq.l	#1,%0\n"

		"	jne	1b\n"

		"4:	btst	#1,%5\n"

		"	jeq	6f\n"

		"	move.w	(%1)+,%3\n"

		"5:	moves.w	%3,(%2)+\n"

		"5:	"MOVES".w	%3,(%2)+\n"

		"6:	btst	#0,%5\n"

		"	jeq	8f\n"

		"	move.b	(%1)+,%3\n"

		"7:	moves.b  %3,(%2)+\n"

		"7:	"MOVES".b  %3,(%2)+\n"

		"8:\n"

		"	.section .fixup,\"ax\"\n"

		"	.even\n"
@@ -115,7 +115,7 @@ long strncpy_from_user(char *dst, const char __user *src, long count) 
		return count;



	asm volatile ("\n"

		"1:	moves.b	(%2)+,%4\n"

		"1:	"MOVES".b	(%2)+,%4\n"

		"	move.b	%4,(%1)+\n"

		"	jeq	2f\n"

		"	subq.l	#1,%3\n"
@@ -152,7 +152,7 @@ long strnlen_user(const char __user *src, long n) 
	asm volatile ("\n"

		"1:	subq.l	#1,%1\n"

		"	jmi	3f\n"

		"2:	moves.b	(%0)+,%2\n"

		"2:	"MOVES".b	(%0)+,%2\n"

		"	tst.b	%2\n"

		"	jne	1b\n"

		"	jra	4f\n"
@@ -188,15 +188,15 @@ unsigned long __clear_user(void __user *to, unsigned long n) 
	asm volatile ("\n"

		"	tst.l	%0\n"

		"	jeq	3f\n"

		"1:	moves.l	%2,(%1)+\n"

		"1:	"MOVES".l	%2,(%1)+\n"

		"2:	subq.l	#1,%0\n"

		"	jne	1b\n"

		"3:	btst	#1,%4\n"

		"	jeq	5f\n"

		"4:	moves.w	%2,(%1)+\n"

		"4:	"MOVES".w	%2,(%1)+\n"

		"5:	btst	#0,%4\n"

		"	jeq	7f\n"

		"6:	moves.b	%2,(%1)\n"

		"6:	"MOVES".b	%2,(%1)\n"

		"7:\n"

		"	.section .fixup,\"ax\"\n"

		"	.even\n"

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