Pull platform-drivers into test branch
[linux-2.6] / arch / powerpc / platforms / chrp / smp.c
1 /*
2  * Smp support for CHRP machines.
3  *
4  * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
5  * deal of code from the sparc and intel versions.
6  *
7  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
8  *
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/smp.h>
14 #include <linux/smp_lock.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/spinlock.h>
20
21 #include <asm/ptrace.h>
22 #include <asm/atomic.h>
23 #include <asm/irq.h>
24 #include <asm/page.h>
25 #include <asm/pgtable.h>
26 #include <asm/sections.h>
27 #include <asm/io.h>
28 #include <asm/prom.h>
29 #include <asm/smp.h>
30 #include <asm/residual.h>
31 #include <asm/time.h>
32 #include <asm/machdep.h>
33 #include <asm/smp.h>
34 #include <asm/mpic.h>
35 #include <asm/rtas.h>
36
37 static void __devinit smp_chrp_kick_cpu(int nr)
38 {
39         *(unsigned long *)KERNELBASE = nr;
40         asm volatile("dcbf 0,%0"::"r"(KERNELBASE):"memory");
41 }
42
43 static void __devinit smp_chrp_setup_cpu(int cpu_nr)
44 {
45         mpic_setup_this_cpu();
46 }
47
48 static DEFINE_SPINLOCK(timebase_lock);
49 static unsigned int timebase_upper = 0, timebase_lower = 0;
50
51 void __devinit smp_chrp_give_timebase(void)
52 {
53         spin_lock(&timebase_lock);
54         rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
55         timebase_upper = get_tbu();
56         timebase_lower = get_tbl();
57         spin_unlock(&timebase_lock);
58
59         while (timebase_upper || timebase_lower)
60                 barrier();
61         rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
62 }
63
64 void __devinit smp_chrp_take_timebase(void)
65 {
66         while (!(timebase_upper || timebase_lower))
67                 barrier();
68         spin_lock(&timebase_lock);
69         set_tb(timebase_upper, timebase_lower);
70         timebase_upper = 0;
71         timebase_lower = 0;
72         spin_unlock(&timebase_lock);
73         printk("CPU %i taken timebase\n", smp_processor_id());
74 }
75
76 /* CHRP with openpic */
77 struct smp_ops_t chrp_smp_ops = {
78         .message_pass = smp_mpic_message_pass,
79         .probe = smp_mpic_probe,
80         .kick_cpu = smp_chrp_kick_cpu,
81         .setup_cpu = smp_chrp_setup_cpu,
82         .give_timebase = smp_chrp_give_timebase,
83         .take_timebase = smp_chrp_take_timebase,
84 };