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 (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         long ctx = 0;
  47
  48         p = p1275buf.prom_buffer;
  49         ctx = spitfire_get_primary_context ();
  50         if (ctx) {
  51                 flushw_user ();
  52                 spitfire_set_primary_context (0);
  53         }
  54
  55         spin_lock_irqsave(&prom_entry_lock, flags);
  56
  57         p1275buf.prom_args[0] = (unsigned long)p;               /* service */
  58         strcpy (p, service);
  59         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  60         p1275buf.prom_args[1] = nargs = (fmt & 0x0f);           /* nargs */
  61         p1275buf.prom_args[2] = nrets = ((fmt & 0xf0) >> 4);    /* nrets */
  62         attrs = fmt >> 8;
  63         va_start(list, fmt);
  64         for (i = 0; i < nargs; i++, attrs >>= 3) {
  65                 switch (attrs & 0x7) {
  66                 case P1275_ARG_NUMBER:
  67                         p1275buf.prom_args[i + 3] =
  68                                                 (unsigned)va_arg(list, long);
  69                         break;
  70                 case P1275_ARG_IN_64B:
  71                         p1275buf.prom_args[i + 3] =
  72                                 va_arg(list, unsigned long);
  73                         break;
  74                 case P1275_ARG_IN_STRING:
  75                         strcpy (p, va_arg(list, char *));
  76                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  77                         p = (char *)(((long)(strchr (p, 0) + 8)) & ~7);
  78                         break;
  79                 case P1275_ARG_OUT_BUF:
  80                         (void) va_arg(list, char *);
  81                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  82                         x = va_arg(list, long);
  83                         i++; attrs >>= 3;
  84                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  85                         p1275buf.prom_args[i + 3] = x;
  86                         break;
  87                 case P1275_ARG_IN_BUF:
  88                         q = va_arg(list, char *);
  89                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  90                         x = va_arg(list, long);
  91                         i++; attrs >>= 3;
  92                         memcpy (p, q, (int)x);
  93                         p = (char *)(((long)(p + (int)x + 7)) & ~7);
  94                         p1275buf.prom_args[i + 3] = x;
  95                         break;
  96                 case P1275_ARG_OUT_32B:
  97                         (void) va_arg(list, char *);
  98                         p1275buf.prom_args[i + 3] = (unsigned long)p;
  99                         p += 32;
 100                         break;
 101                 case P1275_ARG_IN_FUNCTION:
 102                         p1275buf.prom_args[i + 3] =
 103                                         (unsigned long)prom_cif_callback;
 104                         p1275buf.prom_callback = va_arg(list, long);
 105                         break;
 106                 }
 107         }
 108         va_end(list);
 109
 110         prom_world(1);
 111         prom_cif_interface();
 112         prom_world(0);
 113
 114         attrs = fmt >> 8;
 115         va_start(list, fmt);
 116         for (i = 0; i < nargs; i++, attrs >>= 3) {
 117                 switch (attrs & 0x7) {
 118                 case P1275_ARG_NUMBER:
 119                         (void) va_arg(list, long);
 120                         break;
 121                 case P1275_ARG_IN_STRING:
 122                         (void) va_arg(list, char *);
 123                         break;
 124                 case P1275_ARG_IN_FUNCTION:
 125                         (void) va_arg(list, long);
 126                         break;
 127                 case P1275_ARG_IN_BUF:
 128                         (void) va_arg(list, char *);
 129                         (void) va_arg(list, long);
 130                         i++; attrs >>= 3;
 131                         break;
 132                 case P1275_ARG_OUT_BUF:
 133                         p = va_arg(list, char *);
 134                         x = va_arg(list, long);
 135                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), (int)x);
 136                         i++; attrs >>= 3;
 137                         break;
 138                 case P1275_ARG_OUT_32B:
 139                         p = va_arg(list, char *);
 140                         memcpy (p, (char *)(p1275buf.prom_args[i + 3]), 32);
 141                         break;
 142                 }
 143         }
 144         va_end(list);
 145         x = p1275buf.prom_args [nargs + 3];
 146
 147         spin_unlock_irqrestore(&prom_entry_lock, flags);
 148
 149         if (ctx)
 150                 spitfire_set_primary_context (ctx);
 151
 152         return x;
 153 }
 154
 155 void prom_cif_init(void *cif_handler, void *cif_stack)
 156 {
 157         p1275buf.prom_cif_handler = (void (*)(long *))cif_handler;
 158         p1275buf.prom_cif_stack = (unsigned long)cif_stack;
 159 }