arch/s390/include/asm/switch_to.h

   1 /*
   2  * Copyright IBM Corp. 1999, 2009
   3  *
   4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   5  */
   6
   7 #ifndef __ASM_SWITCH_TO_H
   8 #define __ASM_SWITCH_TO_H
   9
  10 #include <linux/thread_info.h>
  11 #include <asm/ptrace.h>
  12
  13 extern struct task_struct *__switch_to(void *, void *);
  14 extern void update_cr_regs(struct task_struct *task);
  15
  16 static inline int test_fp_ctl(u32 fpc)
  17 {
  18         u32 orig_fpc;
  19         int rc;
  20
  21         asm volatile(
  22                 "       efpc    %1\n"
  23                 "       sfpc    %2\n"
  24                 "0:     sfpc    %1\n"
  25                 "       la      %0,0\n"
  26                 "1:\n"
  27                 EX_TABLE(0b,1b)
  28                 : "=d" (rc), "=d" (orig_fpc)
  29                 : "d" (fpc), "0" (-EINVAL));
  30         return rc;
  31 }
  32
  33 static inline void save_fp_ctl(u32 *fpc)
  34 {
  35         asm volatile(
  36                 "       stfpc   %0\n"
  37                 : "+Q" (*fpc));
  38 }
  39
  40 static inline int restore_fp_ctl(u32 *fpc)
  41 {
  42         int rc;
  43
  44         asm volatile(
  45                 "       lfpc    %1\n"
  46                 "0:     la      %0,0\n"
  47                 "1:\n"
  48                 EX_TABLE(0b,1b)
  49                 : "=d" (rc) : "Q" (*fpc), "0" (-EINVAL));
  50         return rc;
  51 }
  52
  53 static inline void save_fp_regs(freg_t *fprs)
  54 {
  55         asm volatile("std 0,%0" : "=Q" (fprs[0]));
  56         asm volatile("std 2,%0" : "=Q" (fprs[2]));
  57         asm volatile("std 4,%0" : "=Q" (fprs[4]));
  58         asm volatile("std 6,%0" : "=Q" (fprs[6]));
  59         asm volatile("std 1,%0" : "=Q" (fprs[1]));
  60         asm volatile("std 3,%0" : "=Q" (fprs[3]));
  61         asm volatile("std 5,%0" : "=Q" (fprs[5]));
  62         asm volatile("std 7,%0" : "=Q" (fprs[7]));
  63         asm volatile("std 8,%0" : "=Q" (fprs[8]));
  64         asm volatile("std 9,%0" : "=Q" (fprs[9]));
  65         asm volatile("std 10,%0" : "=Q" (fprs[10]));
  66         asm volatile("std 11,%0" : "=Q" (fprs[11]));
  67         asm volatile("std 12,%0" : "=Q" (fprs[12]));
  68         asm volatile("std 13,%0" : "=Q" (fprs[13]));
  69         asm volatile("std 14,%0" : "=Q" (fprs[14]));
  70         asm volatile("std 15,%0" : "=Q" (fprs[15]));
  71 }
  72
  73 static inline void restore_fp_regs(freg_t *fprs)
  74 {
  75         asm volatile("ld 0,%0" : : "Q" (fprs[0]));
  76         asm volatile("ld 2,%0" : : "Q" (fprs[2]));
  77         asm volatile("ld 4,%0" : : "Q" (fprs[4]));
  78         asm volatile("ld 6,%0" : : "Q" (fprs[6]));
  79         asm volatile("ld 1,%0" : : "Q" (fprs[1]));
  80         asm volatile("ld 3,%0" : : "Q" (fprs[3]));
  81         asm volatile("ld 5,%0" : : "Q" (fprs[5]));
  82         asm volatile("ld 7,%0" : : "Q" (fprs[7]));
  83         asm volatile("ld 8,%0" : : "Q" (fprs[8]));
  84         asm volatile("ld 9,%0" : : "Q" (fprs[9]));
  85         asm volatile("ld 10,%0" : : "Q" (fprs[10]));
  86         asm volatile("ld 11,%0" : : "Q" (fprs[11]));
  87         asm volatile("ld 12,%0" : : "Q" (fprs[12]));
  88         asm volatile("ld 13,%0" : : "Q" (fprs[13]));
  89         asm volatile("ld 14,%0" : : "Q" (fprs[14]));
  90         asm volatile("ld 15,%0" : : "Q" (fprs[15]));
  91 }
  92
  93 static inline void save_vx_regs(__vector128 *vxrs)
  94 {
  95         typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
  96
  97         asm volatile(
  98                 "       la      1,%0\n"
  99                 "       .word   0xe70f,0x1000,0x003e\n" /* vstm 0,15,0(1) */
 100                 "       .word   0xe70f,0x1100,0x0c3e\n" /* vstm 16,31,256(1) */
 101                 : "=Q" (*(addrtype *) vxrs) : : "1");
 102 }
 103
 104 static inline void save_vx_regs_safe(__vector128 *vxrs)
 105 {
 106         unsigned long cr0, flags;
 107
 108         flags = arch_local_irq_save();
 109         __ctl_store(cr0, 0, 0);
 110         __ctl_set_bit(0, 17);
 111         __ctl_set_bit(0, 18);
 112         save_vx_regs(vxrs);
 113         __ctl_load(cr0, 0, 0);
 114         arch_local_irq_restore(flags);
 115 }
 116
 117 static inline void restore_vx_regs(__vector128 *vxrs)
 118 {
 119         typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
 120
 121         asm volatile(
 122                 "       la      1,%0\n"
 123                 "       .word   0xe70f,0x1000,0x0036\n" /* vlm 0,15,0(1) */
 124                 "       .word   0xe70f,0x1100,0x0c36\n" /* vlm 16,31,256(1) */
 125                 : : "Q" (*(addrtype *) vxrs) : "1");
 126 }
 127
 128 static inline void save_fp_vx_regs(struct task_struct *task)
 129 {
 130         if (task->thread.vxrs)
 131                 save_vx_regs(task->thread.vxrs);
 132         else
 133                 save_fp_regs(task->thread.fp_regs.fprs);
 134 }
 135
 136 static inline void restore_fp_vx_regs(struct task_struct *task)
 137 {
 138         if (task->thread.vxrs)
 139                 restore_vx_regs(task->thread.vxrs);
 140         else
 141                 restore_fp_regs(task->thread.fp_regs.fprs);
 142 }
 143
 144 static inline void save_access_regs(unsigned int *acrs)
 145 {
 146         typedef struct { int _[NUM_ACRS]; } acrstype;
 147
 148         asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
 149 }
 150
 151 static inline void restore_access_regs(unsigned int *acrs)
 152 {
 153         typedef struct { int _[NUM_ACRS]; } acrstype;
 154
 155         asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
 156 }
 157
 158 #define switch_to(prev,next,last) do {                                  \
 159         if (prev->mm) {                                                 \
 160                 save_fp_ctl(&prev->thread.fp_regs.fpc);                 \
 161                 save_fp_vx_regs(prev);                                  \
 162                 save_access_regs(&prev->thread.acrs[0]);                \
 163                 save_ri_cb(prev->thread.ri_cb);                         \
 164         }                                                               \
 165         if (next->mm) {                                                 \
 166                 update_cr_regs(next);                                   \
 167                 restore_fp_ctl(&next->thread.fp_regs.fpc);              \
 168                 restore_fp_vx_regs(next);                               \
 169                 restore_access_regs(&next->thread.acrs[0]);             \
 170                 restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb);  \
 171         }                                                               \
 172         prev = __switch_to(prev,next);                                  \
 173 } while (0)
 174
 175 #endif /* __ASM_SWITCH_TO_H */