root/include/asm-sparc/processor.h

/* */

INCLUDED FROM

DEFINITIONS

1. start_bh_atomic
2. end_bh_atomic
3. start_thread

   1 /* include/asm-sparc/processor.h
   2  *
   3  * Copyright (C) 1994 David S. Miller (davem@caip.rutgers.edu)
   4  */
   5 
   6 #ifndef __ASM_SPARC_PROCESSOR_H
   7 #define __ASM_SPARC_PROCESSOR_H
   8 
   9 #include <linux/sched.h>  /* For intr_count */
  10 
  11 #include <asm/ptrace.h>   /* For pt_regs declaration */
  12 
  13 /*
  14  * Bus types
  15  */
  16 #define EISA_bus 0
  17 #define EISA_bus__is_a_macro /* for versions in ksyms.c */
  18 #define MCA_bus 0
  19 #define MCA_bus__is_a_macro /* for versions in ksyms.c */
  20 
  21 /*
  22  * Write Protection works right in supervisor mode on the Sparc
  23  */
  24 #if 0  /* Let's try this out ;) */
  25 #define wp_works_ok 1
  26 #define wp_works_ok__is_a_macro /* for versions in ksyms.c */
  27 #else
  28 extern char wp_works_ok;
  29 #endif
  30 
  31 /*
  32  * User space process size: 3GB. This is hardcoded into a few places,
  33  * so don't change it unless you know what you are doing.
  34  *
  35  * With the way identity mapping works on the sun4c, this is the best
  36  * value to use.
  37  *
  38  * This has to be looked into for a unified sun4c/sun4m task size.
  39  */
  40 #define TASK_SIZE       (0xC000000UL)
  41 
  42 /*
  43  * Size of io_bitmap in longwords: 32 is ports 0-0x3ff.
  44  */
  45 #define IO_BITMAP_SIZE  32
  46 
  47 /* The first four entries here MUST be the first four. This allows me to
  48  * do %lo(offset) loads and stores in entry.S. See TRAP_WIN_CLEAN to see
  49  * why.
  50  */
  51 
  52 struct thread_struct {
  53         unsigned long uwindows;       /* how many user windows are in the set */
  54         unsigned long wim;            /* user's window invalid mask */
  55         unsigned long w_saved;        /* how many windows saved in reg_window[] */
  56         unsigned long ksp;            /* kernel stack pointer */
  57         unsigned long usp;            /* user's sp, throw reg windows here */
  58         unsigned long psr;            /* save for condition codes */
  59         unsigned long pc;             /* program counter */
  60         unsigned long npc;            /* next program counter */
  61         unsigned long yreg;
  62         unsigned long align;          /* to get 8-byte alignment  XXX  */
  63         unsigned long reg_window[16];
  64         unsigned long pgd_ptr;
  65         int context;                  /* The context allocated to this thread */
  66 
  67 /* 8 local registers + 8 in registers * 24 register windows.
  68  * Most sparcs I know of only have 7 or 8 windows implemented,
  69  * we determine how many at boot time and store that value
  70  * in nwindows.
  71  */
  72         unsigned long float_regs[64]; /* V8 and below have 32, V9 has 64 */
  73 };
  74 
  75 #define INIT_MMAP { &init_task, (PAGE_OFFSET), (0xff000000UL), \
  76                     0x0 , VM_READ | VM_WRITE | VM_EXEC }
  77 
  78 #define INIT_TSS  { \
  79         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
  80         { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, \
  81         (long) &swapper_pg_dir, -1,  \
  82         { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
  83         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
  84         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
  85         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, \
  86 }
  87 
  88 /* The thread_frame is what needs to be set up in certain circumstances
  89  * upon entry to a trap. It is also loaded sometimes during a window
  90  * spill if things don't go right (bad user stack pointer). In reality
  91  * it is not per-process per se, it just sits in the kernel stack while
  92  * the current process is in a handler then it is basically forgotten
  93  * about the next time flow control goes back to that process.
  94  */
  95 
  96 /* Sparc stack save area allocated for each save, not very exciting. */
  97 struct sparc_save_stack {
  98   unsigned int locals[8];
  99   unsigned int ins[8];
 100   unsigned int padd[8];
 101 };
 102 
 103 /*
 104  * These are the "cli()" and "sti()" for software interrupts
 105  * They work by increasing/decreasing the "intr_count" value, 
 106  * and as such can be nested arbitrarily.
 107  */
 108 extern inline void start_bh_atomic(void)
     /*  */
 109 {
 110         __asm__ __volatile__("rd %%psr, %%g2\n\t"
 111                              "wr %%g2, 0x20, %%psr\n\t"  /* disable traps */
 112                              "ld %0,%%g3\n\t"
 113                              "add %%g3,1,%%g3\n\t"
 114                              "st %%g3,%0\n\t"
 115                              "wr %%g2, 0x0, %%psr\n\t"   /* enable traps */
 116                              : "=m" (intr_count)
 117                              : : "g2", "g3", "memory");
 118 }
 119 
 120 extern inline void end_bh_atomic(void)
     /*  */
 121 {
 122         __asm__ __volatile__("rd %%psr, %%g2\n\t"
 123                              "wr %%g2, 0x20, %%psr\n\t"
 124                              "ld %0,%%g3\n\t"
 125                              "sub %%g3,1,%%g3\n\t"
 126                              "st %%g3,%0\n\t"
 127                              "wr %%g2, 0x0, %%psr\n\t"
 128                              : "=m" (intr_count)
 129                              : : "g2", "g3", "memory");
 130 }
 131 
 132 /*
 133  * Do necessary setup to start up a newly executed thread.
 134  */
 135 static inline void start_thread(struct pt_regs * regs, unsigned long sp,
     /*  */
 136                                 unsigned long fp)
 137 {
 138   printk("start_thread called, halting..n");
 139   halt();
 140 }
 141 
 142 #endif /* __ASM_SPARC_PROCESSOR_H */
 143 

/* */