/* devices.c: Initial scan of the prom device tree for important
* Sparc device nodes which we need to find.
*
* This is based on the sparc64 version, but sun4m doesn't always use
* the hardware MIDs, so be careful.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
*/
#include <linux/kernel.h>
#include <linux/threads.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <asm/page.h>
#include <asm/oplib.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/system.h>
#include <asm/cpudata.h>
extern void cpu_probe(void);
extern void clock_stop_probe(void); /* tadpole.c */
extern void sun4c_probe_memerr_reg(void);
static char *cpu_mid_prop(void)
{
if (sparc_cpu_model == sun4d)
return "cpu-id";
return "mid";
}
static int check_cpu_node(int nd, int *cur_inst,
int (*compare)(int, int, void *), void *compare_arg,
int *prom_node, int *mid)
{
if (!compare(nd, *cur_inst, compare_arg)) {
if (prom_node)
*prom_node = nd;
if (mid) {
*mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
if (sparc_cpu_model == sun4m)
*mid &= 3;
}
return 0;
}
(*cur_inst)++;
return -ENODEV;
}
static int __cpu_find_by(int (*compare)(int, int, void *), void *compare_arg,
int *prom_node, int *mid)
{
struct device_node *dp;
int cur_inst;
cur_inst = 0;
for_each_node_by_type(dp, "cpu") {
int err = check_cpu_node(dp->node, &cur_inst,
compare, compare_arg,
prom_node, mid);
if (!err)
return 0;
}
return -ENODEV;
}
static int cpu_instance_compare(int nd, int instance, void *_arg)
{
int desired_instance = (int) _arg;
if (instance == desired_instance)
return 0;
return -ENODEV;
}
int cpu_find_by_instance(int instance, int *prom_node, int *mid)
{
return __cpu_find_by(cpu_instance_compare, (void *)instance,
prom_node, mid);
}
static int cpu_mid_compare(int nd, int instance, void *_arg)
{
int desired_mid = (int) _arg;
int this_mid;
this_mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
if (this_mid == desired_mid
|| (sparc_cpu_model == sun4m && (this_mid & 3) == desired_mid))
return 0;
return -ENODEV;
}
int cpu_find_by_mid(int mid, int *prom_node)
{
return __cpu_find_by(cpu_mid_compare, (void *)mid,
prom_node, NULL);
}
/* sun4m uses truncated mids since we base the cpuid on the ttable/irqset
* address (0-3). This gives us the true hardware mid, which might have
* some other bits set. On 4d hardware and software mids are the same.
*/
int cpu_get_hwmid(int prom_node)
{
return prom_getintdefault(prom_node, cpu_mid_prop(), -ENODEV);
}
void __init device_scan(void)
{
prom_printf("Booting Linux...\n");
#ifndef CONFIG_SMP
{
int err, cpu_node;
err = cpu_find_by_instance(0, &cpu_node, NULL);
if (err) {
/* Probably a sun4e, Sun is trying to trick us ;-) */
prom_printf("No cpu nodes, cannot continue\n");
prom_halt();
}
cpu_data(0).clock_tick = prom_getintdefault(cpu_node,
"clock-frequency",
0);
}
#endif /* !CONFIG_SMP */
cpu_probe();
#ifdef CONFIG_SUN_AUXIO
{
extern void auxio_probe(void);
extern void auxio_power_probe(void);
auxio_probe();
auxio_power_probe();
}
#endif
clock_stop_probe();
if (ARCH_SUN4C_SUN4)
sun4c_probe_memerr_reg();
return;
}
