arch/s390/include/asm/processor.h

   1 /*
   2  *  S390 version
   3  *    Copyright IBM Corp. 1999
   4  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   6  *
   7  *  Derived from "include/asm-i386/processor.h"
   8  *    Copyright (C) 1994, Linus Torvalds
   9  */
  10
  11 #ifndef __ASM_S390_PROCESSOR_H
  12 #define __ASM_S390_PROCESSOR_H
  13
  14 #include <linux/const.h>
  15
  16 #define CIF_MCCK_PENDING        0       /* machine check handling is pending */
  17 #define CIF_ASCE                1       /* user asce needs fixup / uaccess */
  18 #define CIF_NOHZ_DELAY          2       /* delay HZ disable for a tick */
  19 #define CIF_FPU                 3       /* restore FPU registers */
  20 #define CIF_IGNORE_IRQ          4       /* ignore interrupt (for udelay) */
  21 #define CIF_ENABLED_WAIT        5       /* in enabled wait state */
  22
  23 #define _CIF_MCCK_PENDING       _BITUL(CIF_MCCK_PENDING)
  24 #define _CIF_ASCE               _BITUL(CIF_ASCE)
  25 #define _CIF_NOHZ_DELAY         _BITUL(CIF_NOHZ_DELAY)
  26 #define _CIF_FPU                _BITUL(CIF_FPU)
  27 #define _CIF_IGNORE_IRQ         _BITUL(CIF_IGNORE_IRQ)
  28 #define _CIF_ENABLED_WAIT       _BITUL(CIF_ENABLED_WAIT)
  29
  30 #ifndef __ASSEMBLY__
  31
  32 #include <linux/linkage.h>
  33 #include <linux/irqflags.h>
  34 #include <asm/cpu.h>
  35 #include <asm/page.h>
  36 #include <asm/ptrace.h>
  37 #include <asm/setup.h>
  38 #include <asm/runtime_instr.h>
  39 #include <asm/fpu/types.h>
  40 #include <asm/fpu/internal.h>
  41
  42 static inline void set_cpu_flag(int flag)
  43 {
  44         S390_lowcore.cpu_flags |= (1UL << flag);
  45 }
  46
  47 static inline void clear_cpu_flag(int flag)
  48 {
  49         S390_lowcore.cpu_flags &= ~(1UL << flag);
  50 }
  51
  52 static inline int test_cpu_flag(int flag)
  53 {
  54         return !!(S390_lowcore.cpu_flags & (1UL << flag));
  55 }
  56
  57 /*
  58  * Test CIF flag of another CPU. The caller needs to ensure that
  59  * CPU hotplug can not happen, e.g. by disabling preemption.
  60  */
  61 static inline int test_cpu_flag_of(int flag, int cpu)
  62 {
  63         struct lowcore *lc = lowcore_ptr[cpu];
  64         return !!(lc->cpu_flags & (1UL << flag));
  65 }
  66
  67 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
  68
  69 /*
  70  * Default implementation of macro that returns current
  71  * instruction pointer ("program counter").
  72  */
  73 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
  74
  75 static inline void get_cpu_id(struct cpuid *ptr)
  76 {
  77         asm volatile("stidp %0" : "=Q" (*ptr));
  78 }
  79
  80 extern void s390_adjust_jiffies(void);
  81 extern const struct seq_operations cpuinfo_op;
  82 extern int sysctl_ieee_emulation_warnings;
  83 extern void execve_tail(void);
  84
  85 /*
  86  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
  87  */
  88
  89 #define TASK_SIZE_OF(tsk)       ((tsk)->mm->context.asce_limit)
  90 #define TASK_UNMAPPED_BASE      (test_thread_flag(TIF_31BIT) ? \
  91                                         (1UL << 30) : (1UL << 41))
  92 #define TASK_SIZE               TASK_SIZE_OF(current)
  93 #define TASK_MAX_SIZE           (1UL << 53)
  94
  95 #define STACK_TOP               (1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
  96 #define STACK_TOP_MAX           (1UL << 42)
  97
  98 #define HAVE_ARCH_PICK_MMAP_LAYOUT
  99
 100 typedef struct {
 101         __u32 ar4;
 102 } mm_segment_t;
 103
 104 /*
 105  * Thread structure
 106  */
 107 struct thread_struct {
 108         unsigned int  acrs[NUM_ACRS];
 109         unsigned long ksp;              /* kernel stack pointer             */
 110         mm_segment_t mm_segment;
 111         unsigned long gmap_addr;        /* address of last gmap fault. */
 112         unsigned int gmap_write_flag;   /* gmap fault write indication */
 113         unsigned int gmap_int_code;     /* int code of last gmap fault */
 114         unsigned int gmap_pfault;       /* signal of a pending guest pfault */
 115         struct per_regs per_user;       /* User specified PER registers */
 116         struct per_event per_event;     /* Cause of the last PER trap */
 117         unsigned long per_flags;        /* Flags to control debug behavior */
 118         /* pfault_wait is used to block the process on a pfault event */
 119         unsigned long pfault_wait;
 120         struct list_head list;
 121         /* cpu runtime instrumentation */
 122         struct runtime_instr_cb *ri_cb;
 123         unsigned char trap_tdb[256];    /* Transaction abort diagnose block */
 124         /*
 125          * Warning: 'fpu' is dynamically-sized. It *MUST* be at
 126          * the end.
 127          */
 128         struct fpu fpu;                 /* FP and VX register save area */
 129 };
 130
 131 /* Flag to disable transactions. */
 132 #define PER_FLAG_NO_TE                  1UL
 133 /* Flag to enable random transaction aborts. */
 134 #define PER_FLAG_TE_ABORT_RAND          2UL
 135 /* Flag to specify random transaction abort mode:
 136  * - abort each transaction at a random instruction before TEND if set.
 137  * - abort random transactions at a random instruction if cleared.
 138  */
 139 #define PER_FLAG_TE_ABORT_RAND_TEND     4UL
 140
 141 typedef struct thread_struct thread_struct;
 142
 143 /*
 144  * Stack layout of a C stack frame.
 145  */
 146 #ifndef __PACK_STACK
 147 struct stack_frame {
 148         unsigned long back_chain;
 149         unsigned long empty1[5];
 150         unsigned long gprs[10];
 151         unsigned int  empty2[8];
 152 };
 153 #else
 154 struct stack_frame {
 155         unsigned long empty1[5];
 156         unsigned int  empty2[8];
 157         unsigned long gprs[10];
 158         unsigned long back_chain;
 159 };
 160 #endif
 161
 162 #define ARCH_MIN_TASKALIGN      8
 163
 164 #define INIT_THREAD {                                                   \
 165         .ksp = sizeof(init_stack) + (unsigned long) &init_stack,        \
 166         .fpu.regs = (void *) init_task.thread.fpu.fprs,                 \
 167 }
 168
 169 /*
 170  * Do necessary setup to start up a new thread.
 171  */
 172 #define start_thread(regs, new_psw, new_stackp) do {                    \
 173         regs->psw.mask  = PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;    \
 174         regs->psw.addr  = new_psw;                                      \
 175         regs->gprs[15]  = new_stackp;                                   \
 176         execve_tail();                                                  \
 177 } while (0)
 178
 179 #define start_thread31(regs, new_psw, new_stackp) do {                  \
 180         regs->psw.mask  = PSW_USER_BITS | PSW_MASK_BA;                  \
 181         regs->psw.addr  = new_psw;                                      \
 182         regs->gprs[15]  = new_stackp;                                   \
 183         crst_table_downgrade(current->mm);                              \
 184         execve_tail();                                                  \
 185 } while (0)
 186
 187 /* Forward declaration, a strange C thing */
 188 struct task_struct;
 189 struct mm_struct;
 190 struct seq_file;
 191
 192 typedef int (*dump_trace_func_t)(void *data, unsigned long address);
 193 void dump_trace(dump_trace_func_t func, void *data,
 194                 struct task_struct *task, unsigned long sp);
 195
 196 void show_cacheinfo(struct seq_file *m);
 197
 198 /* Free all resources held by a thread. */
 199 extern void release_thread(struct task_struct *);
 200
 201 /*
 202  * Return saved PC of a blocked thread.
 203  */
 204 extern unsigned long thread_saved_pc(struct task_struct *t);
 205
 206 unsigned long get_wchan(struct task_struct *p);
 207 #define task_pt_regs(tsk) ((struct pt_regs *) \
 208         (task_stack_page(tsk) + THREAD_SIZE) - 1)
 209 #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->psw.addr)
 210 #define KSTK_ESP(tsk)   (task_pt_regs(tsk)->gprs[15])
 211
 212 /* Has task runtime instrumentation enabled ? */
 213 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
 214
 215 static inline unsigned long current_stack_pointer(void)
 216 {
 217         unsigned long sp;
 218
 219         asm volatile("la %0,0(15)" : "=a" (sp));
 220         return sp;
 221 }
 222
 223 static inline unsigned short stap(void)
 224 {
 225         unsigned short cpu_address;
 226
 227         asm volatile("stap %0" : "=m" (cpu_address));
 228         return cpu_address;
 229 }
 230
 231 /*
 232  * Give up the time slice of the virtual PU.
 233  */
 234 void cpu_relax(void);
 235
 236 #define cpu_relax_lowlatency()  barrier()
 237
 238 static inline void psw_set_key(unsigned int key)
 239 {
 240         asm volatile("spka 0(%0)" : : "d" (key));
 241 }
 242
 243 /*
 244  * Set PSW to specified value.
 245  */
 246 static inline void __load_psw(psw_t psw)
 247 {
 248         asm volatile("lpswe %0" : : "Q" (psw) : "cc");
 249 }
 250
 251 /*
 252  * Set PSW mask to specified value, while leaving the
 253  * PSW addr pointing to the next instruction.
 254  */
 255 static inline void __load_psw_mask(unsigned long mask)
 256 {
 257         unsigned long addr;
 258         psw_t psw;
 259
 260         psw.mask = mask;
 261
 262         asm volatile(
 263                 "       larl    %0,1f\n"
 264                 "       stg     %0,%O1+8(%R1)\n"
 265                 "       lpswe   %1\n"
 266                 "1:"
 267                 : "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
 268 }
 269
 270 /*
 271  * Extract current PSW mask
 272  */
 273 static inline unsigned long __extract_psw(void)
 274 {
 275         unsigned int reg1, reg2;
 276
 277         asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
 278         return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
 279 }
 280
 281 static inline void local_mcck_enable(void)
 282 {
 283         __load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
 284 }
 285
 286 static inline void local_mcck_disable(void)
 287 {
 288         __load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
 289 }
 290
 291 /*
 292  * Rewind PSW instruction address by specified number of bytes.
 293  */
 294 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
 295 {
 296         unsigned long mask;
 297
 298         mask = (psw.mask & PSW_MASK_EA) ? -1UL :
 299                (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
 300                                           (1UL << 24) - 1;
 301         return (psw.addr - ilc) & mask;
 302 }
 303
 304 /*
 305  * Function to stop a processor until the next interrupt occurs
 306  */
 307 void enabled_wait(void);
 308
 309 /*
 310  * Function to drop a processor into disabled wait state
 311  */
 312 static inline void __noreturn disabled_wait(unsigned long code)
 313 {
 314         psw_t psw;
 315
 316         psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
 317         psw.addr = code;
 318         __load_psw(psw);
 319         while (1);
 320 }
 321
 322 /*
 323  * Basic Machine Check/Program Check Handler.
 324  */
 325
 326 extern void s390_base_mcck_handler(void);
 327 extern void s390_base_pgm_handler(void);
 328 extern void s390_base_ext_handler(void);
 329
 330 extern void (*s390_base_mcck_handler_fn)(void);
 331 extern void (*s390_base_pgm_handler_fn)(void);
 332 extern void (*s390_base_ext_handler_fn)(void);
 333
 334 #define ARCH_LOW_ADDRESS_LIMIT  0x7fffffffUL
 335
 336 extern int memcpy_real(void *, void *, size_t);
 337 extern void memcpy_absolute(void *, void *, size_t);
 338
 339 #define mem_assign_absolute(dest, val) {                        \
 340         __typeof__(dest) __tmp = (val);                         \
 341                                                                 \
 342         BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));             \
 343         memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));        \
 344 }
 345
 346 #endif /* __ASSEMBLY__ */
 347
 348 #endif /* __ASM_S390_PROCESSOR_H */