include/asm-mips64/processor.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 Waldorf GMBH
   7  * Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000 Ralf Baechle
   8  * Modified further for R[236]000 compatibility by Paul M. Antoine
   9  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  10  */
  11 #ifndef _ASM_PROCESSOR_H
  12 #define _ASM_PROCESSOR_H
  13
  14 #include <linux/config.h>
  15
  16 /*
  17  * Return current * instruction pointer ("program counter").
  18  *
  19  * Two implementations.  The ``la'' version results in shorter code for
  20  * the kernel which we assume to reside in the 32-bit compat address space.
  21  * The  ``jal'' version is for use by modules which live in outer space.
  22  * This is just a single instruction unlike the long dla macro expansion.
  23  */
  24 #ifdef MODULE
  25 #define current_text_addr()                                             \
  26 ({                                                                      \
  27         void *_a;                                                       \
  28                                                                         \
  29         __asm__ ("jal\t1f, 1f\n\t"                                      \
  30                 "1:"                                                    \
  31                 : "=r" (_a));                                           \
  32                                                                         \
  33         _a;                                                             \
  34 })
  35 #else
  36 #define current_text_addr()                                             \
  37 ({                                                                      \
  38         void *_a;                                                       \
  39                                                                         \
  40         __asm__ ("dla\t%0, 1f\n\t"                                      \
  41                 "1:"                                                    \
  42                 : "=r" (_a));                                           \
  43                                                                         \
  44         _a;                                                             \
  45 })
  46 #endif
  47
  48 #if !defined (_LANGUAGE_ASSEMBLY)
  49 #include <asm/cachectl.h>
  50 #include <asm/mipsregs.h>
  51 #include <asm/reg.h>
  52 #include <asm/system.h>
  53
  54 #if (defined(CONFIG_SGI_IP27))
  55 #include <asm/sn/types.h>
  56 #include <asm/sn/intr_public.h>
  57 #endif
  58
  59 struct cpuinfo_mips {
  60         unsigned long udelay_val;
  61         unsigned long *pgd_quick;
  62         unsigned long *pmd_quick;
  63         unsigned long *pte_quick;
  64         unsigned long pgtable_cache_sz;
  65         unsigned long last_asn;
  66         unsigned long asid_cache;
  67 #if defined(CONFIG_SGI_IP27)
  68         cpuid_t         p_cpuid;        /* PROM assigned cpuid */
  69         cnodeid_t       p_nodeid;       /* my node ID in compact-id-space */
  70         nasid_t         p_nasid;        /* my node ID in numa-as-id-space */
  71         unsigned char   p_slice;        /* Physical position on node board */
  72         hub_intmasks_t  p_intmasks;     /* SN0 per-CPU interrupt masks */
  73 #endif
  74 } __attribute__((aligned(128)));
  75
  76 /*
  77  * System setup and hardware flags..
  78  * XXX: Should go into mips_cpuinfo.
  79  */
  80 extern char wait_available;             /* only available on R4[26]00 */
  81 extern char cyclecounter_available;     /* only available from R4000 upwards. */
  82 extern char dedicated_iv_available;     /* some embedded MIPS like Nevada */
  83 extern char vce_available;              /* Supports VCED / VCEI exceptions */
  84 extern char mips4_available;            /* CPU has MIPS IV ISA or better */
  85
  86 extern unsigned int vced_count, vcei_count;
  87 extern struct cpuinfo_mips cpu_data[];
  88
  89 #ifdef CONFIG_SMP
  90 #define current_cpu_data cpu_data[smp_processor_id()]
  91 #else
  92 #define current_cpu_data cpu_data[0]
  93 #endif
  94
  95 /*
  96  * Bus types (default is ISA, but people can check others with these..)
  97  * MCA_bus hardcoded to 0 for now.
  98  *
  99  * This needs to be extended since MIPS systems are being delivered with
 100  * numerous different types of bus systems.
 101  */
 102 extern int EISA_bus;
 103 #define MCA_bus 0
 104 #define MCA_bus__is_a_macro /* for versions in ksyms.c */
 105
 106 /*
 107  * MIPS has no problems with write protection
 108  */
 109 #define wp_works_ok 1
 110 #define wp_works_ok__is_a_macro /* for versions in ksyms.c */
 111
 112 /* Lazy FPU handling on uni-processor */
 113 extern struct task_struct *last_task_used_math;
 114
 115 #ifndef CONFIG_SMP
 116 #define IS_FPU_OWNER()          (last_task_used_math == current)
 117 #define CLEAR_FPU_OWNER()       last_task_used_math = NULL;
 118 #else
 119 #define IS_FPU_OWNER()          (current->flags & PF_USEDFPU)
 120 #define CLEAR_FPU_OWNER()       current->flags &= ~PF_USEDFPU;
 121 #endif
 122
 123 /*
 124  * User space process size: 1TB. This is hardcoded into a few places,
 125  * so don't change it unless you know what you are doing.  TASK_SIZE
 126  * is limited to 1TB by the R4000 architecture; R10000 and better can
 127  * support 16TB.
 128  */
 129 #define TASK_SIZE32        0x80000000UL
 130 #define TASK_SIZE       0x10000000000UL
 131
 132 /* This decides where the kernel will search for a free chunk of vm
 133  * space during mmap's.
 134  */
 135 #define TASK_UNMAPPED_BASE      ((current->thread.mflags & MF_32BIT) ? \
 136         (TASK_SIZE32 / 3) : (TASK_SIZE / 3))
 137
 138 /*
 139  * Size of io_bitmap in longwords: 32 is ports 0-0x3ff.
 140  */
 141 #define IO_BITMAP_SIZE  32
 142
 143 #define NUM_FPU_REGS    32
 144
 145 struct mips_fpu_hard_struct {
 146         unsigned long fp_regs[NUM_FPU_REGS];
 147         unsigned int control;
 148 };
 149
 150 /*
 151  * FIXME: no fpu emulator yet (but who cares anyway?)
 152  */
 153 struct mips_fpu_soft_struct {
 154         long    dummy;
 155 };
 156
 157 union mips_fpu_union {
 158         struct mips_fpu_hard_struct hard;
 159         struct mips_fpu_soft_struct soft;
 160 };
 161
 162 #define INIT_FPU { \
 163         {{0,},} \
 164 }
 165
 166 typedef struct {
 167         unsigned long seg;
 168 } mm_segment_t;
 169
 170 /*
 171  * If you change thread_struct remember to change the #defines below too!
 172  */
 173 struct thread_struct {
 174         /* Saved main processor registers. */
 175         unsigned long reg16;
 176         unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
 177         unsigned long reg29, reg30, reg31;
 178
 179         /* Saved cp0 stuff. */
 180         unsigned long cp0_status;
 181
 182         /* Saved fpu/fpu emulator stuff. */
 183         union mips_fpu_union fpu;
 184
 185         /* Other stuff associated with the thread. */
 186         unsigned long cp0_badvaddr;     /* Last user fault */
 187         unsigned long cp0_baduaddr;     /* Last kernel fault accessing USEG */
 188         unsigned long error_code;
 189         unsigned long trap_no;
 190 #define MF_FIXADE 1                     /* Fix address errors in software */
 191 #define MF_LOGADE 2                     /* Log address errors to syslog */
 192 #define MF_32BIT  4                     /* Process is in 32-bit compat mode */
 193         unsigned long mflags;
 194         mm_segment_t current_ds;
 195         unsigned long irix_trampoline;  /* Wheee... */
 196         unsigned long irix_oldctx;
 197 };
 198
 199 #endif /* !defined (_LANGUAGE_ASSEMBLY) */
 200
 201 #define INIT_MMAP { &init_mm, KSEG0, KSEG1, NULL, PAGE_SHARED, \
 202                     VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }
 203
 204 #define INIT_THREAD  { \
 205         /* \
 206          * saved main processor registers \
 207          */ \
 208         0, 0, 0, 0, 0, 0, 0, 0, \
 209                        0, 0, 0, \
 210         /* \
 211          * saved cp0 stuff \
 212          */ \
 213         0, \
 214         /* \
 215          * saved fpu/fpu emulator stuff \
 216          */ \
 217         INIT_FPU, \
 218         /* \
 219          * Other stuff associated with the process \
 220          */ \
 221         0, 0, 0, 0, \
 222         /* \
 223          * For now the default is to fix address errors \
 224          */ \
 225         MF_FIXADE, { 0 }, 0, 0 \
 226 }
 227
 228 #ifdef __KERNEL__
 229
 230 #define KERNEL_STACK_SIZE 0x4000
 231
 232 #if !defined (_LANGUAGE_ASSEMBLY)
 233
 234 /* Free all resources held by a thread. */
 235 #define release_thread(thread) do { } while(0)
 236
 237 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 238
 239 /* Copy and release all segment info associated with a VM */
 240 #define copy_segments(p, mm) do { } while(0)
 241 #define release_segments(mm) do { } while(0)
 242
 243 /*
 244  * Return saved PC of a blocked thread.
 245  */
 246 extern inline unsigned long thread_saved_pc(struct thread_struct *t)
 247 {
 248         extern void ret_from_sys_call(void);
 249
 250         /* New born processes are a special case */
 251         if (t->reg31 == (unsigned long) ret_from_sys_call)
 252                 return t->reg31;
 253
 254         return ((unsigned long*)t->reg29)[11];
 255 }
 256
 257 #define user_mode(regs) (((regs)->cp0_status & ST0_KSU) == KSU_USER)
 258
 259 /*
 260  * Do necessary setup to start up a newly executed thread.
 261  */
 262 #define start_thread(regs, pc, sp)                                      \
 263 do {                                                                    \
 264         unsigned long __status;                                         \
 265                                                                         \
 266         /* New thread looses kernel privileges. */                      \
 267         __status = regs->cp0_status & ~(ST0_CU0|ST0_FR|ST0_KSU);        \
 268         __status |= KSU_USER;                                           \
 269         __status |= (current->thread.mflags & MF_32BIT) ? 0 : ST0_FR;   \
 270         regs->cp0_status = __status;                                    \
 271         regs->cp0_epc = pc;                                             \
 272         regs->regs[29] = sp;                                            \
 273         current->thread.current_ds = USER_DS;                           \
 274 } while(0)
 275
 276 unsigned long get_wchan(struct task_struct *p);
 277
 278 #define __PT_REG(reg) ((long)&((struct pt_regs *)0)->reg - sizeof(struct pt_regs))
 279 #define __KSTK_TOS(tsk) ((unsigned long)(tsk) + KERNEL_STACK_SIZE - 32)
 280 #define KSTK_EIP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_epc)))
 281 #define KSTK_ESP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(regs[29])))
 282
 283 /* Allocation and freeing of basic task resources. */
 284 /*
 285  * NOTE! The task struct and the stack go together
 286  */
 287 #define THREAD_SIZE (2*PAGE_SIZE)
 288 #define alloc_task_struct() \
 289         ((struct task_struct *) __get_free_pages(GFP_KERNEL, 2))
 290 #define free_task_struct(p)     free_pages((unsigned long)(p), 2)
 291 #define get_task_struct(tsk)    atomic_inc(&virt_to_page(tsk)->count)
 292
 293 #define init_task       (init_task_union.task)
 294 #define init_stack      (init_task_union.stack)
 295
 296 #endif /* !defined (_LANGUAGE_ASSEMBLY) */
 297 #endif /* __KERNEL__ */
 298
 299 /*
 300  * Return_address is a replacement for __builtin_return_address(count)
 301  * which on certain architectures cannot reasonably be implemented in GCC
 302  * (MIPS, Alpha) or is unuseable with -fomit-frame-pointer (i386).
 303  * Note that __builtin_return_address(x>=1) is forbidden because GCC
 304  * aborts compilation on some CPUs.  It's simply not possible to unwind
 305  * some CPU's stackframes.
 306  *
 307  * In gcc 2.8 and newer  __builtin_return_address works only for non-leaf
 308  * functions.  We avoid the overhead of a function call by forcing the
 309  * compiler to save the return address register on the stack.
 310  */
 311 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
 312
 313 #endif /* _ASM_PROCESSOR_H */