arch/sparc64/prom/p1275.c

   1 /* $Id: p1275.c,v 1.22 2001/10/18 09:40:00 davem Exp $
   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
  20 struct {
  21         long prom_callback;                     /* 0x00 */
  22         void (*prom_cif_handler)(long *);       /* 0x08 */
  23         unsigned long prom_cif_stack;           /* 0x10 */
  24         unsigned long prom_args [23];           /* 0x18 */
  25         char prom_buffer [3000];
  26 } p1275buf;
  27
  28 extern void prom_world(int);
  29
  30 extern void prom_cif_interface(void);
  31 extern void prom_cif_callback(void);
  32
  33 /*
  34  * This provides SMP safety on the p1275buf. prom_callback() drops this lock
  35  * to allow recursuve acquisition.
  36  */
  37 DEFINE_SPINLOCK(prom_entry_lock);
  38
  39 long p1275_cmd(const char *service, long fmt, ...)
  40 {
  41         char *p, *q;
  42         unsigned long flags;
  43         int nargs, nrets, i;
  44         va_list list;
  45         long attrs, x;
  46
  47         p = p1275buf.prom_buffer;
  48
  49         spin_lock_irqsave(&prom_entry_lock, flags);
  50
  51         p1275buf.prom_args[0] = (unsigned long)p;               /* service */
  52         strcpy (p, service);
  53         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  54         p1275buf.prom_args[1] = nargs = (fmt & 0x0f);           /* nargs */
  55         p1275buf.prom_args[2] = nrets = ((fmt & 0xf0) >> 4);    /* nrets */
  56         attrs = fmt >> 8;
  57         va_start(list, fmt);
  58         for (i = 0; i < nargs; i++, attrs >>= 3) {
  59                 switch (attrs & 0x7) {
  60                 case P1275_ARG_NUMBER:
  61                         p1275buf.prom_args[i + 3] =
  62                                                 (unsigned)va_arg(list, long);
  63                         break;
  64                 case P1275_ARG_IN_64B:
  65                         p1275buf.prom_args[i + 3] =
  66                                 va_arg(list, unsigned long);
  67                         break;
  68                 case P1275_ARG_IN_STRING:
  69                         strcpy (p, va_arg(list, char *));
  70                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  71                         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  72                         break;
  73                 case P1275_ARG_OUT_BUF:
  74                         (void) va_arg(list, char *);
  75                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  76                         x = va_arg(list, long);
  77                         i++; attrs >>= 3;
  78                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  79                         p1275buf.prom_args[i + 3] = x;
  80                         break;
  81                 case P1275_ARG_IN_BUF:
  82                         q = va_arg(list, char *);
  83                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  84                         x = va_arg(list, long);
  85                         i++; attrs >>= 3;
  86                         memcpy (p, q, (int)x);
  87                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  88                         p1275buf.prom_args[i + 3] = x;
  89                         break;
  90                 case P1275_ARG_OUT_32B:
  91                         (void) va_arg(list, char *);
  92                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  93                         p += 32;
  94                         break;
  95                 case P1275_ARG_IN_FUNCTION:
  96                         p1275buf.prom_args[i + 3] =
  97                                         (unsigned long)prom_cif_callback;
  98                         p1275buf.prom_callback = va_arg(list, long);
  99                         break;
 100                 }
 101         }
 102         va_end(list);
 103
 104         prom_world(1);
 105         prom_cif_interface();
 106         prom_world(0);
 107
 108         attrs = fmt >> 8;
 109         va_start(list, fmt);
 110         for (i = 0; i < nargs; i++, attrs >>= 3) {
 111                 switch (attrs & 0x7) {
 112                 case P1275_ARG_NUMBER:
 113                         (void) va_arg(list, long);
 114                         break;
 115                 case P1275_ARG_IN_STRING:
 116                         (void) va_arg(list, char *);
 117                         break;
 118                 case P1275_ARG_IN_FUNCTION:
 119                         (void) va_arg(list, long);
 120                         break;
 121                 case P1275_ARG_IN_BUF:
 122                         (void) va_arg(list, char *);
 123                         (void) va_arg(list, long);
 124                         i++; attrs >>= 3;
 125                         break;
 126                 case P1275_ARG_OUT_BUF:
 127                         p = va_arg(list, char *);
 128                         x = va_arg(list, long);
 129                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), (int)x);
 130                         i++; attrs >>= 3;
 131                         break;
 132                 case P1275_ARG_OUT_32B:
 133                         p = va_arg(list, char *);
 134                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), 32);
 135                         break;
 136                 }
 137         }
 138         va_end(list);
 139         x = p1275buf.prom_args [nargs + 3];
 140
 141         spin_unlock_irqrestore(&prom_entry_lock, flags);
 142
 143         return x;
 144 }
 145
 146 void prom_cif_init(void *cif_handler, void *cif_stack)
 147 {
 148         p1275buf.prom_cif_handler = (void (*)(long *))cif_handler;
 149         p1275buf.prom_cif_stack = (unsigned long)cif_stack;
 150 }