arch/sparc/prom/p1275.c

   1 /*
   2  * p1275.c: Sun IEEE 1275 PROM low level interface routines
   3  *
   4  * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/init.h>
   9 #include <linux/sched.h>
  10 #include <linux/smp.h>
  11 #include <linux/string.h>
  12 #include <linux/spinlock.h>
  13
  14 #include <asm/openprom.h>
  15 #include <asm/oplib.h>
  16 #include <asm/system.h>
  17 #include <asm/spitfire.h>
  18 #include <asm/pstate.h>
  19 #include <asm/ldc.h>
  20
  21 struct {
  22         long prom_callback;                     /* 0x00 */
  23         void (*prom_cif_handler)(long *);       /* 0x08 */
  24         unsigned long prom_cif_stack;           /* 0x10 */
  25         unsigned long prom_args [23];           /* 0x18 */
  26         char prom_buffer [3000];
  27 } p1275buf;
  28
  29 extern void prom_world(int);
  30
  31 extern void prom_cif_interface(void);
  32 extern void prom_cif_callback(void);
  33
  34 /*
  35  * This provides SMP safety on the p1275buf. prom_callback() drops this lock
  36  * to allow recursuve acquisition.
  37  */
  38 DEFINE_SPINLOCK(prom_entry_lock);
  39
  40 long p1275_cmd(const char *service, long fmt, ...)
  41 {
  42         char *p, *q;
  43         unsigned long flags;
  44         int nargs, nrets, i;
  45         va_list list;
  46         long attrs, x;
  47
  48         p = p1275buf.prom_buffer;
  49
  50         spin_lock_irqsave(&prom_entry_lock, flags);
  51
  52         p1275buf.prom_args[0] = (unsigned long)p;               /* service */
  53         strcpy (p, service);
  54         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  55         p1275buf.prom_args[1] = nargs = (fmt & 0x0f);           /* nargs */
  56         p1275buf.prom_args[2] = nrets = ((fmt & 0xf0) >> 4);    /* nrets */
  57         attrs = fmt >> 8;
  58         va_start(list, fmt);
  59         for (i = 0; i < nargs; i++, attrs >>= 3) {
  60                 switch (attrs & 0x7) {
  61                 case P1275_ARG_NUMBER:
  62                         p1275buf.prom_args[i + 3] =
  63                                                 (unsigned)va_arg(list, long);
  64                         break;
  65                 case P1275_ARG_IN_64B:
  66                         p1275buf.prom_args[i + 3] =
  67                                 va_arg(list, unsigned long);
  68                         break;
  69                 case P1275_ARG_IN_STRING:
  70                         strcpy (p, va_arg(list, char *));
  71                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  72                         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  73                         break;
  74                 case P1275_ARG_OUT_BUF:
  75                         (void) va_arg(list, char *);
  76                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  77                         x = va_arg(list, long);
  78                         i++; attrs >>= 3;
  79                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  80                         p1275buf.prom_args[i + 3] = x;
  81                         break;
  82                 case P1275_ARG_IN_BUF:
  83                         q = va_arg(list, char *);
  84                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  85                         x = va_arg(list, long);
  86                         i++; attrs >>= 3;
  87                         memcpy (p, q, (int)x);
  88                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  89                         p1275buf.prom_args[i + 3] = x;
  90                         break;
  91                 case P1275_ARG_OUT_32B:
  92                         (void) va_arg(list, char *);
  93                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  94                         p += 32;
  95                         break;
  96                 case P1275_ARG_IN_FUNCTION:
  97                         p1275buf.prom_args[i + 3] =
  98                                         (unsigned long)prom_cif_callback;
  99                         p1275buf.prom_callback = va_arg(list, long);
 100                         break;
 101                 }
 102         }
 103         va_end(list);
 104
 105         prom_world(1);
 106         prom_cif_interface();
 107         prom_world(0);
 108
 109         attrs = fmt >> 8;
 110         va_start(list, fmt);
 111         for (i = 0; i < nargs; i++, attrs >>= 3) {
 112                 switch (attrs & 0x7) {
 113                 case P1275_ARG_NUMBER:
 114                         (void) va_arg(list, long);
 115                         break;
 116                 case P1275_ARG_IN_STRING:
 117                         (void) va_arg(list, char *);
 118                         break;
 119                 case P1275_ARG_IN_FUNCTION:
 120                         (void) va_arg(list, long);
 121                         break;
 122                 case P1275_ARG_IN_BUF:
 123                         (void) va_arg(list, char *);
 124                         (void) va_arg(list, long);
 125                         i++; attrs >>= 3;
 126                         break;
 127                 case P1275_ARG_OUT_BUF:
 128                         p = va_arg(list, char *);
 129                         x = va_arg(list, long);
 130                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), (int)x);
 131                         i++; attrs >>= 3;
 132                         break;
 133                 case P1275_ARG_OUT_32B:
 134                         p = va_arg(list, char *);
 135                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), 32);
 136                         break;
 137                 }
 138         }
 139         va_end(list);
 140         x = p1275buf.prom_args [nargs + 3];
 141
 142         spin_unlock_irqrestore(&prom_entry_lock, flags);
 143
 144         return x;
 145 }
 146
 147 void prom_cif_init(void *cif_handler, void *cif_stack)
 148 {
 149         p1275buf.prom_cif_handler = (void (*)(long *))cif_handler;
 150         p1275buf.prom_cif_stack = (unsigned long)cif_stack;
 151 }