diff options
| -rw-r--r-- | arch/m68k/include/asm/entry_no.h | 12 | ||||
| -rw-r--r-- | arch/m68k/include/asm/system.h | 194 | ||||
| -rw-r--r-- | arch/m68k/include/asm/system_mm.h | 193 | ||||
| -rw-r--r-- | arch/m68k/include/asm/system_no.h | 153 | ||||
| -rw-r--r-- | arch/m68k/platform/68328/entry.S | 13 | ||||
| -rw-r--r-- | arch/m68k/platform/68360/entry.S | 13 | ||||
| -rw-r--r-- | arch/m68k/platform/coldfire/entry.S | 24 |
7 files changed, 222 insertions, 380 deletions
diff --git a/arch/m68k/include/asm/entry_no.h b/arch/m68k/include/asm/entry_no.h index 627d69bacc58..68611e3dbb1d 100644 --- a/arch/m68k/include/asm/entry_no.h +++ b/arch/m68k/include/asm/entry_no.h @@ -96,11 +96,11 @@ .endm .macro RDUSP - movel sw_usp,%a2 + movel sw_usp,%a3 .endm .macro WRUSP - movel %a0,sw_usp + movel %a3,sw_usp .endm #else /* !CONFIG_COLDFIRE_SW_A7 */ @@ -127,13 +127,13 @@ .endm .macro RDUSP - /*move %usp,%a2*/ - .word 0x4e6a + /*move %usp,%a3*/ + .word 0x4e6b .endm .macro WRUSP - /*move %a0,%usp*/ - .word 0x4e60 + /*move %a3,%usp*/ + .word 0x4e63 .endm #endif /* !CONFIG_COLDFIRE_SW_A7 */ diff --git a/arch/m68k/include/asm/system.h b/arch/m68k/include/asm/system.h index ccea925ff4f5..47b01f4726bc 100644 --- a/arch/m68k/include/asm/system.h +++ b/arch/m68k/include/asm/system.h @@ -1,5 +1,193 @@ -#ifdef __uClinux__ -#include "system_no.h" +#ifndef _M68K_SYSTEM_H +#define _M68K_SYSTEM_H + +#include <linux/linkage.h> +#include <linux/kernel.h> +#include <linux/irqflags.h> +#include <asm/segment.h> +#include <asm/entry.h> + +#ifdef __KERNEL__ + +/* + * switch_to(n) should switch tasks to task ptr, first checking that + * ptr isn't the current task, in which case it does nothing. This + * also clears the TS-flag if the task we switched to has used the + * math co-processor latest. + */ +/* + * switch_to() saves the extra registers, that are not saved + * automatically by SAVE_SWITCH_STACK in resume(), ie. d0-d5 and + * a0-a1. Some of these are used by schedule() and its predecessors + * and so we might get see unexpected behaviors when a task returns + * with unexpected register values. + * + * syscall stores these registers itself and none of them are used + * by syscall after the function in the syscall has been called. + * + * Beware that resume now expects *next to be in d1 and the offset of + * tss to be in a1. This saves a few instructions as we no longer have + * to push them onto the stack and read them back right after. + * + * 02/17/96 - Jes Sorensen (jds@kom.auc.dk) + * + * Changed 96/09/19 by Andreas Schwab + * pass prev in a0, next in a1 + */ +asmlinkage void resume(void); +#define switch_to(prev,next,last) do { \ + register void *_prev __asm__ ("a0") = (prev); \ + register void *_next __asm__ ("a1") = (next); \ + register void *_last __asm__ ("d1"); \ + __asm__ __volatile__("jbsr resume" \ + : "=a" (_prev), "=a" (_next), "=d" (_last) \ + : "0" (_prev), "1" (_next) \ + : "d0", "d2", "d3", "d4", "d5"); \ + (last) = _last; \ +} while (0) + + +/* + * Force strict CPU ordering. + * Not really required on m68k... + */ +#define nop() do { asm volatile ("nop"); barrier(); } while (0) +#define mb() barrier() +#define rmb() barrier() +#define wmb() barrier() +#define read_barrier_depends() ((void)0) +#define set_mb(var, value) ({ (var) = (value); wmb(); }) + +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#define smp_read_barrier_depends() ((void)0) + +#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) + +struct __xchg_dummy { unsigned long a[100]; }; +#define __xg(x) ((volatile struct __xchg_dummy *)(x)) + +#ifndef CONFIG_RMW_INSNS +static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) +{ + unsigned long flags, tmp; + + local_irq_save(flags); + + switch (size) { + case 1: + tmp = *(u8 *)ptr; + *(u8 *)ptr = x; + x = tmp; + break; + case 2: + tmp = *(u16 *)ptr; + *(u16 *)ptr = x; + x = tmp; + break; + case 4: + tmp = *(u32 *)ptr; + *(u32 *)ptr = x; + x = tmp; + break; + default: + BUG(); + } + + local_irq_restore(flags); + return x; +} #else -#include "system_mm.h" +static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) +{ + switch (size) { + case 1: + __asm__ __volatile__ + ("moveb %2,%0\n\t" + "1:\n\t" + "casb %0,%1,%2\n\t" + "jne 1b" + : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + break; + case 2: + __asm__ __volatile__ + ("movew %2,%0\n\t" + "1:\n\t" + "casw %0,%1,%2\n\t" + "jne 1b" + : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + break; + case 4: + __asm__ __volatile__ + ("movel %2,%0\n\t" + "1:\n\t" + "casl %0,%1,%2\n\t" + "jne 1b" + : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); + break; + } + return x; +} #endif + +#include <asm-generic/cmpxchg-local.h> + +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) + +/* + * Atomic compare and exchange. Compare OLD with MEM, if identical, + * store NEW in MEM. Return the initial value in MEM. Success is + * indicated by comparing RETURN with OLD. + */ +#ifdef CONFIG_RMW_INSNS +#define __HAVE_ARCH_CMPXCHG 1 + +static inline unsigned long __cmpxchg(volatile void *p, unsigned long old, + unsigned long new, int size) +{ + switch (size) { + case 1: + __asm__ __volatile__ ("casb %0,%2,%1" + : "=d" (old), "=m" (*(char *)p) + : "d" (new), "0" (old), "m" (*(char *)p)); + break; + case 2: + __asm__ __volatile__ ("casw %0,%2,%1" + : "=d" (old), "=m" (*(short *)p) + : "d" (new), "0" (old), "m" (*(short *)p)); + break; + case 4: + __asm__ __volatile__ ("casl %0,%2,%1" + : "=d" (old), "=m" (*(int *)p) + : "d" (new), "0" (old), "m" (*(int *)p)); + break; + } + return old; +} + +#define cmpxchg(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ + (unsigned long)(n), sizeof(*(ptr)))) +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ + (unsigned long)(n), sizeof(*(ptr)))) +#else + +/* + * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make + * them available. + */ +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ + (unsigned long)(n), sizeof(*(ptr)))) + +#include <asm-generic/cmpxchg.h> + +#endif + +#define arch_align_stack(x) (x) + +#endif /* __KERNEL__ */ + +#endif /* _M68K_SYSTEM_H */ diff --git a/arch/m68k/include/asm/system_mm.h b/arch/m68k/include/asm/system_mm.h deleted file mode 100644 index 47b01f4726bc..000000000000 --- a/arch/m68k/include/asm/system_mm.h +++ /dev/null @@ -1,193 +0,0 @@ -#ifndef _M68K_SYSTEM_H -#define _M68K_SYSTEM_H - -#include <linux/linkage.h> -#include <linux/kernel.h> -#include <linux/irqflags.h> -#include <asm/segment.h> -#include <asm/entry.h> - -#ifdef __KERNEL__ - -/* - * switch_to(n) should switch tasks to task ptr, first checking that - * ptr isn't the current task, in which case it does nothing. This - * also clears the TS-flag if the task we switched to has used the - * math co-processor latest. - */ -/* - * switch_to() saves the extra registers, that are not saved - * automatically by SAVE_SWITCH_STACK in resume(), ie. d0-d5 and - * a0-a1. Some of these are used by schedule() and its predecessors - * and so we might get see unexpected behaviors when a task returns - * with unexpected register values. - * - * syscall stores these registers itself and none of them are used - * by syscall after the function in the syscall has been called. - * - * Beware that resume now expects *next to be in d1 and the offset of - * tss to be in a1. This saves a few instructions as we no longer have - * to push them onto the stack and read them back right after. - * - * 02/17/96 - Jes Sorensen (jds@kom.auc.dk) - * - * Changed 96/09/19 by Andreas Schwab - * pass prev in a0, next in a1 - */ -asmlinkage void resume(void); -#define switch_to(prev,next,last) do { \ - register void *_prev __asm__ ("a0") = (prev); \ - register void *_next __asm__ ("a1") = (next); \ - register void *_last __asm__ ("d1"); \ - __asm__ __volatile__("jbsr resume" \ - : "=a" (_prev), "=a" (_next), "=d" (_last) \ - : "0" (_prev), "1" (_next) \ - : "d0", "d2", "d3", "d4", "d5"); \ - (last) = _last; \ -} while (0) - - -/* - * Force strict CPU ordering. - * Not really required on m68k... - */ -#define nop() do { asm volatile ("nop"); barrier(); } while (0) -#define mb() barrier() -#define rmb() barrier() -#define wmb() barrier() -#define read_barrier_depends() ((void)0) -#define set_mb(var, value) ({ (var) = (value); wmb(); }) - -#define smp_mb() barrier() -#define smp_rmb() barrier() -#define smp_wmb() barrier() -#define smp_read_barrier_depends() ((void)0) - -#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) - -struct __xchg_dummy { unsigned long a[100]; }; -#define __xg(x) ((volatile struct __xchg_dummy *)(x)) - -#ifndef CONFIG_RMW_INSNS -static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) -{ - unsigned long flags, tmp; - - local_irq_save(flags); - - switch (size) { - case 1: - tmp = *(u8 *)ptr; - *(u8 *)ptr = x; - x = tmp; - break; - case 2: - tmp = *(u16 *)ptr; - *(u16 *)ptr = x; - x = tmp; - break; - case 4: - tmp = *(u32 *)ptr; - *(u32 *)ptr = x; - x = tmp; - break; - default: - BUG(); - } - - local_irq_restore(flags); - return x; -} -#else -static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) -{ - switch (size) { - case 1: - __asm__ __volatile__ - ("moveb %2,%0\n\t" - "1:\n\t" - "casb %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 2: - __asm__ __volatile__ - ("movew %2,%0\n\t" - "1:\n\t" - "casw %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 4: - __asm__ __volatile__ - ("movel %2,%0\n\t" - "1:\n\t" - "casl %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - } - return x; -} -#endif - -#include <asm-generic/cmpxchg-local.h> - -#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) - -/* - * Atomic compare and exchange. Compare OLD with MEM, if identical, - * store NEW in MEM. Return the initial value in MEM. Success is - * indicated by comparing RETURN with OLD. - */ -#ifdef CONFIG_RMW_INSNS -#define __HAVE_ARCH_CMPXCHG 1 - -static inline unsigned long __cmpxchg(volatile void *p, unsigned long old, - unsigned long new, int size) -{ - switch (size) { - case 1: - __asm__ __volatile__ ("casb %0,%2,%1" - : "=d" (old), "=m" (*(char *)p) - : "d" (new), "0" (old), "m" (*(char *)p)); - break; - case 2: - __asm__ __volatile__ ("casw %0,%2,%1" - : "=d" (old), "=m" (*(short *)p) - : "d" (new), "0" (old), "m" (*(short *)p)); - break; - case 4: - __asm__ __volatile__ ("casl %0,%2,%1" - : "=d" (old), "=m" (*(int *)p) - : "d" (new), "0" (old), "m" (*(int *)p)); - break; - } - return old; -} - -#define cmpxchg(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ - (unsigned long)(n), sizeof(*(ptr)))) -#define cmpxchg_local(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ - (unsigned long)(n), sizeof(*(ptr)))) -#else - -/* - * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make - * them available. - */ -#define cmpxchg_local(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ - (unsigned long)(n), sizeof(*(ptr)))) - -#include <asm-generic/cmpxchg.h> - -#endif - -#define arch_align_stack(x) (x) - -#endif /* __KERNEL__ */ - -#endif /* _M68K_SYSTEM_H */ diff --git a/arch/m68k/include/asm/system_no.h b/arch/m68k/include/asm/system_no.h deleted file mode 100644 index 6fe9f93bc3ff..000000000000 --- a/arch/m68k/include/asm/system_no.h +++ /dev/null @@ -1,153 +0,0 @@ -#ifndef _M68KNOMMU_SYSTEM_H -#define _M68KNOMMU_SYSTEM_H - -#include <linux/linkage.h> -#include <linux/irqflags.h> -#include <asm/segment.h> -#include <asm/entry.h> - -/* - * switch_to(n) should switch tasks to task ptr, first checking that - * ptr isn't the current task, in which case it does nothing. This - * also clears the TS-flag if the task we switched to has used the - * math co-processor latest. - */ -/* - * switch_to() saves the extra registers, that are not saved - * automatically by SAVE_SWITCH_STACK in resume(), ie. d0-d5 and - * a0-a1. Some of these are used by schedule() and its predecessors - * and so we might get see unexpected behaviors when a task returns - * with unexpected register values. - * - * syscall stores these registers itself and none of them are used - * by syscall after the function in the syscall has been called. - * - * Beware that resume now expects *next to be in d1 and the offset of - * tss to be in a1. This saves a few instructions as we no longer have - * to push them onto the stack and read them back right after. - * - * 02/17/96 - Jes Sorensen (jds@kom.auc.dk) - * - * Changed 96/09/19 by Andreas Schwab - * pass prev in a0, next in a1, offset of tss in d1, and whether - * the mm structures are shared in d2 (to avoid atc flushing). - */ -asmlinkage void resume(void); -#define switch_to(prev,next,last) \ -{ \ - void *_last; \ - __asm__ __volatile__( \ - "movel %1, %%a0\n\t" \ - "movel %2, %%a1\n\t" \ - "jbsr resume\n\t" \ - "movel %%d1, %0\n\t" \ - : "=d" (_last) \ - : "d" (prev), "d" (next) \ - : "cc", "d0", "d1", "d2", "d3", "d4", "d5", "a0", "a1"); \ - (last) = _last; \ -} - -#define iret() __asm__ __volatile__ ("rte": : :"memory", "sp", "cc") - -/* - * Force strict CPU ordering. - * Not really required on m68k... - */ -#define nop() asm volatile ("nop"::) -#define mb() asm volatile ("" : : :"memory") -#define rmb() asm volatile ("" : : :"memory") -#define wmb() asm volatile ("" : : :"memory") -#define set_mb(var, value) ({ (var) = (value); wmb(); }) - -#define smp_mb() barrier() -#define smp_rmb() barrier() -#define smp_wmb() barrier() -#define smp_read_barrier_depends() do { } while(0) - -#define read_barrier_depends() ((void)0) - -#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) - -struct __xchg_dummy { unsigned long a[100]; }; -#define __xg(x) ((volatile struct __xchg_dummy *)(x)) - -#ifndef CONFIG_RMW_INSNS -static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) -{ - unsigned long tmp, flags; - - local_irq_save(flags); - - switch (size) { - case 1: - __asm__ __volatile__ - ("moveb %2,%0\n\t" - "moveb %1,%2" - : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 2: - __asm__ __volatile__ - ("movew %2,%0\n\t" - "movew %1,%2" - : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 4: - __asm__ __volatile__ - ("movel %2,%0\n\t" - "movel %1,%2" - : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - } - local_irq_restore(flags); - return tmp; -} -#else -static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) -{ - switch (size) { - case 1: - __asm__ __volatile__ - ("moveb %2,%0\n\t" - "1:\n\t" - "casb %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 2: - __asm__ __volatile__ - ("movew %2,%0\n\t" - "1:\n\t" - "casw %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - case 4: - __asm__ __volatile__ - ("movel %2,%0\n\t" - "1:\n\t" - "casl %0,%1,%2\n\t" - "jne 1b" - : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); - break; - } - return x; -} -#endif - -#include <asm-generic/cmpxchg-local.h> - -/* - * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make - * them available. - */ -#define cmpxchg_local(ptr, o, n) \ - ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ - (unsigned long)(n), sizeof(*(ptr)))) -#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) - -#include <asm-generic/cmpxchg.h> - -#define arch_align_stack(x) (x) - - -#endif /* _M68KNOMMU_SYSTEM_H */ diff --git a/arch/m68k/platform/68328/entry.S b/arch/m68k/platform/68328/entry.S index f68dce766c0a..4ed7a65d5aa0 100644 --- a/arch/m68k/platform/68328/entry.S +++ b/arch/m68k/platform/68328/entry.S @@ -241,22 +241,21 @@ ENTRY(bad_interrupt) /* * Beware - when entering resume, prev (the current task) is - * in a0, next (the new task) is in a1,so don't change these + * in a0, next (the new task) is in a1, so don't change these * registers until their contents are no longer needed. */ ENTRY(resume) movel %a0,%d1 /* save prev thread in d1 */ movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */ - movel %usp,%a2 /* save usp */ - movel %a2,%a0@(TASK_THREAD+THREAD_USP) - SAVE_SWITCH_STACK movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */ + movel %usp,%a3 /* save usp */ + movel %a3,%a0@(TASK_THREAD+THREAD_USP) + + movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore user stack */ + movel %a3,%usp movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */ RESTORE_SWITCH_STACK - - movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore user stack */ - movel %a0,%usp movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */ rts diff --git a/arch/m68k/platform/68360/entry.S b/arch/m68k/platform/68360/entry.S index a07b14feed92..0ede6702127a 100644 --- a/arch/m68k/platform/68360/entry.S +++ b/arch/m68k/platform/68360/entry.S @@ -162,22 +162,21 @@ bad_interrupt: /* * Beware - when entering resume, prev (the current task) is - * in a0, next (the new task) is in a1,so don't change these + * in a0, next (the new task) is in a1, so don't change these * registers until their contents are no longer needed. */ ENTRY(resume) movel %a0,%d1 /* save prev thread in d1 */ movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */ - movel %usp,%a2 /* save usp */ - movel %a2,%a0@(TASK_THREAD+THREAD_USP) - SAVE_SWITCH_STACK movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */ + movel %usp,%a3 /* save usp */ + movel %a3,%a0@(TASK_THREAD+THREAD_USP) + + movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore user stack */ + movel %a3,%usp movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */ RESTORE_SWITCH_STACK - - movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore user stack */ - movel %a0,%usp movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */ rts diff --git a/arch/m68k/platform/coldfire/entry.S b/arch/m68k/platform/coldfire/entry.S index 27c2b001161e..bd27242c2f43 100644 --- a/arch/m68k/platform/coldfire/entry.S +++ b/arch/m68k/platform/coldfire/entry.S @@ -182,21 +182,23 @@ ENTRY(inthandler) /* * Beware - when entering resume, prev (the current task) is - * in a0, next (the new task) is in a1,so don't change these + * in a0, next (the new task) is in a1, so don't change these * registers until their contents are no longer needed. - * This is always called in supervisor mode, so don't bother to save - * and restore sr; user's process sr is actually in the stack. */ ENTRY(resume) - movel %a0, %d1 /* get prev thread in d1 */ - RDUSP - movel %a2,%a0@(TASK_THREAD+THREAD_USP) - + movew %sr,%d1 /* save current status */ + movew %d1,%a0@(TASK_THREAD+THREAD_SR) + movel %a0,%d1 /* get prev thread in d1 */ SAVE_SWITCH_STACK movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack pointer */ - movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */ + RDUSP /* movel %usp,%a3 */ + movel %a3,%a0@(TASK_THREAD+THREAD_USP) /* save thread user stack */ + + 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 */ + movew %a1@(TASK_THREAD+THREAD_SR),%d7 /* restore new status */ + movew %d7,%sr RESTORE_SWITCH_STACK - - movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */ - WRUSP rts + |