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m68k: modify user space access functions to support ColdFire CPUs

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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: Greg Ungerer <gerg@uclinux.org>
Acked-by: Matt Waddel <mwaddel@yahoo.com>
Acked-by: Kurt Mahan <kmahan@xmission.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Greg Ungerer 2011-10-14 14:43:30 +10:00
parent 2c9b82adb5
commit e08d703cc2
5 changed files with 49 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/m68k/Kconfig
View File

@ -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

4
arch/m68k/Kconfig.cpu
View File

@ -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.

4
arch/m68k/include/asm/segment.h
View File

@ -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");

42
arch/m68k/include/asm/uaccess_mm.h
View File

@ -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" \

22
arch/m68k/lib/uaccess.c
View File

@ -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"