arch/sparc64/kernel/devices.c

   1 /* devices.c: Initial scan of the prom device tree for important
   2  *            Sparc device nodes which we need to find.
   3  *
   4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7 #include <linux/config.h>
   8 #include <linux/kernel.h>
   9 #include <linux/threads.h>
  10 #include <linux/init.h>
  11 #include <linux/ioport.h>
  12 #include <linux/string.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/errno.h>
  15
  16 #include <asm/page.h>
  17 #include <asm/oplib.h>
  18 #include <asm/system.h>
  19 #include <asm/smp.h>
  20 #include <asm/spitfire.h>
  21 #include <asm/timer.h>
  22 #include <asm/cpudata.h>
  23
  24 /* Used to synchronize acceses to NatSemi SUPER I/O chip configure
  25  * operations in asm/ns87303.h
  26  */
  27 DEFINE_SPINLOCK(ns87303_lock);
  28
  29 extern void cpu_probe(void);
  30 extern void central_probe(void);
  31
  32 static char *cpu_mid_prop(void)
  33 {
  34         if (tlb_type == spitfire)
  35                 return "upa-portid";
  36         return "portid";
  37 }
  38
  39 static int check_cpu_node(int nd, int *cur_inst,
  40                           int (*compare)(int, int, void *), void *compare_arg,
  41                           int *prom_node, int *mid)
  42 {
  43         char node_str[128];
  44
  45         prom_getstring(nd, "device_type", node_str, sizeof(node_str));
  46         if (strcmp(node_str, "cpu"))
  47                 return -ENODEV;
  48
  49         if (!compare(nd, *cur_inst, compare_arg)) {
  50                 if (prom_node)
  51                         *prom_node = nd;
  52                 if (mid)
  53                         *mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
  54                 return 0;
  55         }
  56
  57         (*cur_inst)++;
  58
  59         return -ENODEV;
  60 }
  61
  62 static int __cpu_find_by(int (*compare)(int, int, void *), void *compare_arg,
  63                          int *prom_node, int *mid)
  64 {
  65         int nd, cur_inst, err;
  66
  67         nd = prom_root_node;
  68         cur_inst = 0;
  69
  70         err = check_cpu_node(nd, &cur_inst,
  71                              compare, compare_arg,
  72                              prom_node, mid);
  73         if (err == 0)
  74                 return 0;
  75
  76         nd = prom_getchild(nd);
  77         while ((nd = prom_getsibling(nd)) != 0) {
  78                 err = check_cpu_node(nd, &cur_inst,
  79                                      compare, compare_arg,
  80                                      prom_node, mid);
  81                 if (err == 0)
  82                         return 0;
  83         }
  84
  85         return -ENODEV;
  86 }
  87
  88 static int cpu_instance_compare(int nd, int instance, void *_arg)
  89 {
  90         int desired_instance = (int) (long) _arg;
  91
  92         if (instance == desired_instance)
  93                 return 0;
  94         return -ENODEV;
  95 }
  96
  97 int cpu_find_by_instance(int instance, int *prom_node, int *mid)
  98 {
  99         return __cpu_find_by(cpu_instance_compare, (void *)(long)instance,
 100                              prom_node, mid);
 101 }
 102
 103 static int cpu_mid_compare(int nd, int instance, void *_arg)
 104 {
 105         int desired_mid = (int) (long) _arg;
 106         int this_mid;
 107
 108         this_mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
 109         if (this_mid == desired_mid)
 110                 return 0;
 111         return -ENODEV;
 112 }
 113
 114 int cpu_find_by_mid(int mid, int *prom_node)
 115 {
 116         return __cpu_find_by(cpu_mid_compare, (void *)(long)mid,
 117                              prom_node, NULL);
 118 }
 119
 120 void __init device_scan(void)
 121 {
 122         /* FIX ME FAST... -DaveM */
 123         ioport_resource.end = 0xffffffffffffffffUL;
 124
 125         prom_printf("Booting Linux...\n");
 126
 127 #ifndef CONFIG_SMP
 128         {
 129                 int err, cpu_node;
 130                 err = cpu_find_by_instance(0, &cpu_node, NULL);
 131                 if (err) {
 132                         prom_printf("No cpu nodes, cannot continue\n");
 133                         prom_halt();
 134                 }
 135                 cpu_data(0).clock_tick = prom_getintdefault(cpu_node,
 136                                                             "clock-frequency",
 137                                                             0);
 138         }
 139 #endif
 140
 141         central_probe();
 142
 143         cpu_probe();
 144 }