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 
14 #include <asm/page.h>
15 #include <asm/oplib.h>
16 #include <asm/system.h>
17 #include <asm/smp.h>
18 #include <asm/spitfire.h>
19 
20 struct prom_cpuinfo linux_cpus[64] __initdata = { { 0 } };
21 unsigned prom_cpu_nodes[64];
22 int linux_num_cpus = 0;
23 
24 extern void cpu_probe(void);
25 extern void central_probe(void);
26 
device_scan(void)27 void __init device_scan(void)
28 {
29 	char node_str[128];
30 	int nd, prom_node_cpu, thismid;
31 	int cpu_nds[64];  /* One node for each cpu */
32 	int cpu_ctr = 0;
33 
34 	/* FIX ME FAST... -DaveM */
35 	ioport_resource.end = 0xffffffffffffffffUL;
36 	iomem_resource.end = 0xffffffffffffffffUL;
37 
38 	prom_getstring(prom_root_node, "device_type", node_str, sizeof(node_str));
39 
40 	prom_printf("Booting Linux...\n");
41 	if(strcmp(node_str, "cpu") == 0) {
42 		cpu_nds[0] = prom_root_node;
43 		linux_cpus[0].prom_node = prom_root_node;
44 		linux_cpus[0].mid = 0;
45 		cpu_ctr++;
46 	} else {
47 		int scan;
48 		scan = prom_getchild(prom_root_node);
49 		/* prom_printf("root child is %08x\n", (unsigned) scan); */
50 		nd = 0;
51 		while((scan = prom_getsibling(scan)) != 0) {
52 			prom_getstring(scan, "device_type", node_str, sizeof(node_str));
53 			if(strcmp(node_str, "cpu") == 0) {
54 				cpu_nds[cpu_ctr] = scan;
55 				linux_cpus[cpu_ctr].prom_node = scan;
56 				thismid = 0;
57 				if (tlb_type == spitfire) {
58 					prom_getproperty(scan, "upa-portid",
59 							 (char *) &thismid, sizeof(thismid));
60 				} else if (tlb_type == cheetah ||
61 					   tlb_type == cheetah_plus) {
62 					prom_getproperty(scan, "portid",
63 							 (char *) &thismid, sizeof(thismid));
64 				}
65 				linux_cpus[cpu_ctr].mid = thismid;
66 				printk("Found CPU %d (node=%08x,mid=%d)\n",
67 				       cpu_ctr, (unsigned) scan, thismid);
68 				cpu_ctr++;
69 			}
70 		};
71 		if(cpu_ctr == 0) {
72 			prom_printf("No CPU nodes found, cannot continue.\n");
73 			prom_halt();
74 		}
75 		printk("Found %d CPU prom device tree node(s).\n", cpu_ctr);
76 	}
77 	prom_node_cpu = cpu_nds[0];
78 
79 	linux_num_cpus = cpu_ctr;
80 
81 	prom_cpu_nodes[0] = prom_node_cpu;
82 
83 #ifndef CONFIG_SMP
84 	{
85 		extern unsigned long up_clock_tick;
86 		up_clock_tick = prom_getintdefault(prom_node_cpu,
87 						   "clock-frequency",
88 						   0);
89 	}
90 #endif
91 
92 	central_probe();
93 
94 	cpu_probe();
95 }
96