Commit bbc6f1ba authored by Greg Ungerer's avatar Greg Ungerer
Browse files

m68k: set register a2 to current if MMU enabled on ColdFire 



Virtual memory m68k systems build with register a2 dedicated to being the
current proc pointer (non-MMU don't do this). Add code to the ColdFire
interrupt and exception processing to set this on entry, and at context
switch time. We use the same GET_CURRENT() macro that MMU enabled code
uses - modifying it so that the assembler is ColdFire clean.

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 88be3515

arch/m68k/include/asm/entry.h

+9 −1
Original line number Diff line number Diff line
@@ -222,16 +222,24 @@ 
 * Non-MMU systems do not reserve %a2 in this way, and this definition is

 * not used for them.

 */

#ifdef CONFIG_MMU



#define curptr a2



#define GET_CURRENT(tmp) get_current tmp

.macro get_current reg=%d0

	movel	%sp,\reg

	andw	#-THREAD_SIZE,\reg

	andl	#-THREAD_SIZE,\reg

	movel	\reg,%curptr

	movel	%curptr@,%curptr

.endm



#else



#define GET_CURRENT(tmp)



#endif /* CONFIG_MMU */



#else /* C source */



#define STR(X) STR1(X)

arch/m68k/kernel/entry_no.S

+3 −0
Original line number Diff line number Diff line
@@ -44,6 +44,7 @@ 


ENTRY(buserr)

	SAVE_ALL_INT

	GET_CURRENT(%d0)

	movel	%sp,%sp@- 		/* stack frame pointer argument */

	jsr	buserr_c

	addql	#4,%sp
@@ -51,6 +52,7 @@ ENTRY(buserr) 


ENTRY(trap)

	SAVE_ALL_INT

	GET_CURRENT(%d0)

	movel	%sp,%sp@- 		/* stack frame pointer argument */

	jsr	trap_c

	addql	#4,%sp
@@ -61,6 +63,7 @@ ENTRY(trap) 
.globl dbginterrupt

ENTRY(dbginterrupt)

	SAVE_ALL_INT

	GET_CURRENT(%d0)

	movel	%sp,%sp@- 		/* stack frame pointer argument */

	jsr	dbginterrupt_c

	addql	#4,%sp

arch/m68k/platform/coldfire/entry.S

+5 −1
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ enosys: 
ENTRY(system_call)

	SAVE_ALL_SYS

	move	#0x2000,%sr		/* enable intrs again */

	GET_CURRENT(%d2)



	cmpl	#NR_syscalls,%d0

	jcc	enosys
@@ -165,6 +166,7 @@ Lsignal_return: 
 */

ENTRY(inthandler)

	SAVE_ALL_INT

	GET_CURRENT(%d2)



	movew	%sp@(PT_OFF_FORMATVEC),%d0 /* put exception # in d0 */

	andl	#0x03fc,%d0		/* mask out vector only */
@@ -190,7 +192,9 @@ ENTRY(resume) 
	movel	%sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack pointer */

	RDUSP					 /* movel %usp,%a3 */

	movel	%a3,%a0@(TASK_THREAD+THREAD_USP) /* save thread user stack */



#ifdef CONFIG_MMU

	movel	%a1,%a2				 /* set new current */

#endif

	movel	%a1@(TASK_THREAD+THREAD_USP),%a3 /* restore thread user stack */

	WRUSP					 /* movel %a3,%usp */

	movel	%a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new kernel stack */

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