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-rw-r--r--arch/sparc/kernel/devices.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/sparc/kernel/devices.c b/arch/sparc/kernel/devices.c
new file mode 100644
index 00000000000..fcb0c049c3f
--- /dev/null
+++ b/arch/sparc/kernel/devices.c
@@ -0,0 +1,160 @@
+/* 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/config.h>
+#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/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)
+{
+ char node_str[128];
+
+ prom_getstring(nd, "device_type", node_str, sizeof(node_str));
+ if (strcmp(node_str, "cpu"))
+ return -ENODEV;
+
+ 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)
+{
+ int nd, cur_inst, err;
+
+ nd = prom_root_node;
+ cur_inst = 0;
+
+ err = check_cpu_node(nd, &cur_inst, compare, compare_arg,
+ prom_node, mid);
+ if (!err)
+ return 0;
+
+ nd = prom_getchild(nd);
+ while ((nd = prom_getsibling(nd)) != 0) {
+ err = check_cpu_node(nd, &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;
+}