arch/sparc/include/asm/system_32.h

   1 #ifndef __SPARC_SYSTEM_H
   2 #define __SPARC_SYSTEM_H
   3
   4 #include <linux/kernel.h>
   5 #include <linux/threads.h>      /* NR_CPUS */
   6 #include <linux/thread_info.h>
   7
   8 #include <asm/page.h>
   9 #include <asm/psr.h>
  10 #include <asm/ptrace.h>
  11 #include <asm/btfixup.h>
  12 #include <asm/smp.h>
  13
  14 #ifndef __ASSEMBLY__
  15
  16 #include <linux/irqflags.h>
  17
  18 static inline unsigned int probe_irq_mask(unsigned long val)
  19 {
  20         return 0;
  21 }
  22
  23 /*
  24  * Sparc (general) CPU types
  25  */
  26 enum sparc_cpu {
  27   sun4        = 0x00,
  28   sun4c       = 0x01,
  29   sun4m       = 0x02,
  30   sun4d       = 0x03,
  31   sun4e       = 0x04,
  32   sun4u       = 0x05, /* V8 ploos ploos */
  33   sun_unknown = 0x06,
  34   ap1000      = 0x07, /* almost a sun4m */
  35   sparc_leon  = 0x08, /* Leon SoC */
  36 };
  37
  38 /* Really, userland should not be looking at any of this... */
  39 #ifdef __KERNEL__
  40
  41 extern enum sparc_cpu sparc_cpu_model;
  42
  43 #define ARCH_SUN4C (sparc_cpu_model==sun4c)
  44
  45 #define SUN4M_NCPUS            4              /* Architectural limit of sun4m. */
  46
  47 extern char reboot_command[];
  48
  49 extern struct thread_info *current_set[NR_CPUS];
  50
  51 extern unsigned long empty_bad_page;
  52 extern unsigned long empty_bad_page_table;
  53 extern unsigned long empty_zero_page;
  54
  55 extern void sun_do_break(void);
  56 extern int serial_console;
  57 extern int stop_a_enabled;
  58 extern int scons_pwroff;
  59
  60 static inline int con_is_present(void)
  61 {
  62         return serial_console ? 0 : 1;
  63 }
  64
  65 /* When a context switch happens we must flush all user windows so that
  66  * the windows of the current process are flushed onto its stack. This
  67  * way the windows are all clean for the next process and the stack
  68  * frames are up to date.
  69  */
  70 extern void flush_user_windows(void);
  71 extern void kill_user_windows(void);
  72 extern void synchronize_user_stack(void);
  73 extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
  74                    void *fpqueue, unsigned long *fpqdepth);
  75
  76 #ifdef CONFIG_SMP
  77 #define SWITCH_ENTER(prv) \
  78         do {                    \
  79         if (test_tsk_thread_flag(prv, TIF_USEDFPU)) { \
  80                 put_psr(get_psr() | PSR_EF); \
  81                 fpsave(&(prv)->thread.float_regs[0], &(prv)->thread.fsr, \
  82                        &(prv)->thread.fpqueue[0], &(prv)->thread.fpqdepth); \
  83                 clear_tsk_thread_flag(prv, TIF_USEDFPU); \
  84                 (prv)->thread.kregs->psr &= ~PSR_EF; \
  85         } \
  86         } while(0)
  87
  88 #define SWITCH_DO_LAZY_FPU(next)        /* */
  89 #else
  90 #define SWITCH_ENTER(prv)               /* */
  91 #define SWITCH_DO_LAZY_FPU(nxt) \
  92         do {                    \
  93         if (last_task_used_math != (nxt))               \
  94                 (nxt)->thread.kregs->psr&=~PSR_EF;      \
  95         } while(0)
  96 #endif
  97
  98 extern void flushw_all(void);
  99
 100 /*
 101  * Flush windows so that the VM switch which follows
 102  * would not pull the stack from under us.
 103  *
 104  * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work)
 105  * XXX WTF is the above comment? Found in late teen 2.4.x.
 106  */
 107 #define prepare_arch_switch(next) do { \
 108         __asm__ __volatile__( \
 109         ".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \
 110         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
 111         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
 112         "save %sp, -0x40, %sp\n\t" \
 113         "restore; restore; restore; restore; restore; restore; restore"); \
 114 } while(0)
 115
 116         /* Much care has gone into this code, do not touch it.
 117          *
 118          * We need to loadup regs l0/l1 for the newly forked child
 119          * case because the trap return path relies on those registers
 120          * holding certain values, gcc is told that they are clobbered.
 121          * Gcc needs registers for 3 values in and 1 value out, so we
 122          * clobber every non-fixed-usage register besides l2/l3/o4/o5.  -DaveM
 123          *
 124          * Hey Dave, that do not touch sign is too much of an incentive
 125          * - Anton & Pete
 126          */
 127 #define switch_to(prev, next, last) do {                                                \
 128         SWITCH_ENTER(prev);                                                             \
 129         SWITCH_DO_LAZY_FPU(next);                                                       \
 130         cpumask_set_cpu(smp_processor_id(), mm_cpumask(next->active_mm));               \
 131         __asm__ __volatile__(                                                           \
 132         "sethi  %%hi(here - 0x8), %%o7\n\t"                                             \
 133         "mov    %%g6, %%g3\n\t"                                                         \
 134         "or     %%o7, %%lo(here - 0x8), %%o7\n\t"                                       \
 135         "rd     %%psr, %%g4\n\t"                                                        \
 136         "std    %%sp, [%%g6 + %4]\n\t"                                                  \
 137         "rd     %%wim, %%g5\n\t"                                                        \
 138         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
 139         "nop\n\t"                                                                       \
 140         "std    %%g4, [%%g6 + %3]\n\t"                                                  \
 141         "ldd    [%2 + %3], %%g4\n\t"                                                    \
 142         "mov    %2, %%g6\n\t"                                                           \
 143         ".globl patchme_store_new_current\n"                                            \
 144 "patchme_store_new_current:\n\t"                                                        \
 145         "st     %2, [%1]\n\t"                                                           \
 146         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
 147         "nop\n\t"                                                                       \
 148         "nop\n\t"                                                                       \
 149         "nop\n\t"       /* LEON needs all 3 nops: load to %sp depends on CWP. */                \
 150         "ldd    [%%g6 + %4], %%sp\n\t"                                                  \
 151         "wr     %%g5, 0x0, %%wim\n\t"                                                   \
 152         "ldd    [%%sp + 0x00], %%l0\n\t"                                                \
 153         "ldd    [%%sp + 0x38], %%i6\n\t"                                                \
 154         "wr     %%g4, 0x0, %%psr\n\t"                                                   \
 155         "nop\n\t"                                                                       \
 156         "nop\n\t"                                                                       \
 157         "jmpl   %%o7 + 0x8, %%g0\n\t"                                                   \
 158         " ld    [%%g3 + %5], %0\n\t"                                                    \
 159         "here:\n"                                                                       \
 160         : "=&r" (last)                                                                  \
 161         : "r" (&(current_set[hard_smp_processor_id()])),        \
 162           "r" (task_thread_info(next)),                         \
 163           "i" (TI_KPSR),                                        \
 164           "i" (TI_KSP),                                         \
 165           "i" (TI_TASK)                                         \
 166         :       "g1", "g2", "g3", "g4", "g5",       "g7",       \
 167           "l0", "l1",       "l3", "l4", "l5", "l6", "l7",       \
 168           "i0", "i1", "i2", "i3", "i4", "i5",                   \
 169           "o0", "o1", "o2", "o3",                   "o7");      \
 170         } while(0)
 171
 172 /* XXX Change this if we ever use a PSO mode kernel. */
 173 #define mb()    __asm__ __volatile__ ("" : : : "memory")
 174 #define rmb()   mb()
 175 #define wmb()   mb()
 176 #define read_barrier_depends()  do { } while(0)
 177 #define set_mb(__var, __value)  do { __var = __value; mb(); } while(0)
 178 #define smp_mb()        __asm__ __volatile__("":::"memory")
 179 #define smp_rmb()       __asm__ __volatile__("":::"memory")
 180 #define smp_wmb()       __asm__ __volatile__("":::"memory")
 181 #define smp_read_barrier_depends()      do { } while(0)
 182
 183 #define nop() __asm__ __volatile__ ("nop")
 184
 185 /* This has special calling conventions */
 186 #ifndef CONFIG_SMP
 187 BTFIXUPDEF_CALL(void, ___xchg32, void)
 188 #endif
 189
 190 static inline unsigned long xchg_u32(__volatile__ unsigned long *m, unsigned long val)
 191 {
 192 #ifdef CONFIG_SMP
 193         __asm__ __volatile__("swap [%2], %0"
 194                              : "=&r" (val)
 195                              : "0" (val), "r" (m)
 196                              : "memory");
 197         return val;
 198 #else
 199         register unsigned long *ptr asm("g1");
 200         register unsigned long ret asm("g2");
 201
 202         ptr = (unsigned long *) m;
 203         ret = val;
 204
 205         /* Note: this is magic and the nop there is
 206            really needed. */
 207         __asm__ __volatile__(
 208         "mov    %%o7, %%g4\n\t"
 209         "call   ___f____xchg32\n\t"
 210         " nop\n\t"
 211         : "=&r" (ret)
 212         : "0" (ret), "r" (ptr)
 213         : "g3", "g4", "g7", "memory", "cc");
 214
 215         return ret;
 216 #endif
 217 }
 218
 219 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 220
 221 extern void __xchg_called_with_bad_pointer(void);
 222
 223 static inline unsigned long __xchg(unsigned long x, __volatile__ void * ptr, int size)
 224 {
 225         switch (size) {
 226         case 4:
 227                 return xchg_u32(ptr, x);
 228         };
 229         __xchg_called_with_bad_pointer();
 230         return x;
 231 }
 232
 233 /* Emulate cmpxchg() the same way we emulate atomics,
 234  * by hashing the object address and indexing into an array
 235  * of spinlocks to get a bit of performance...
 236  *
 237  * See arch/sparc/lib/atomic32.c for implementation.
 238  *
 239  * Cribbed from <asm-parisc/atomic.h>
 240  */
 241 #define __HAVE_ARCH_CMPXCHG     1
 242
 243 /* bug catcher for when unsupported size is used - won't link */
 244 extern void __cmpxchg_called_with_bad_pointer(void);
 245 /* we only need to support cmpxchg of a u32 on sparc */
 246 extern unsigned long __cmpxchg_u32(volatile u32 *m, u32 old, u32 new_);
 247
 248 /* don't worry...optimizer will get rid of most of this */
 249 static inline unsigned long
 250 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
 251 {
 252         switch (size) {
 253         case 4:
 254                 return __cmpxchg_u32((u32 *)ptr, (u32)old, (u32)new_);
 255         default:
 256                 __cmpxchg_called_with_bad_pointer();
 257                 break;
 258         }
 259         return old;
 260 }
 261
 262 #define cmpxchg(ptr, o, n)                                              \
 263 ({                                                                      \
 264         __typeof__(*(ptr)) _o_ = (o);                                   \
 265         __typeof__(*(ptr)) _n_ = (n);                                   \
 266         (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,       \
 267                         (unsigned long)_n_, sizeof(*(ptr)));            \
 268 })
 269
 270 #include <asm-generic/cmpxchg-local.h>
 271
 272 /*
 273  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 274  * them available.
 275  */
 276 #define cmpxchg_local(ptr, o, n)                                               \
 277         ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
 278                         (unsigned long)(n), sizeof(*(ptr))))
 279 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 280
 281 extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
 282
 283 #endif /* __KERNEL__ */
 284
 285 #endif /* __ASSEMBLY__ */
 286
 287 #define arch_align_stack(x) (x)
 288
 289 #endif /* !(__SPARC_SYSTEM_H) */