[PATCH] ppc64: POWER5+ oprofile support
[linux-2.6] / arch / ppc / 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/config.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/smp.h>
15 #include <linux/smp_lock.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
18 #include <linux/delay.h>
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21
22 #include <asm/ptrace.h>
23 #include <asm/atomic.h>
24 #include <asm/irq.h>
25 #include <asm/page.h>
26 #include <asm/pgtable.h>
27 #include <asm/sections.h>
28 #include <asm/io.h>
29 #include <asm/prom.h>
30 #include <asm/smp.h>
31 #include <asm/residual.h>
32 #include <asm/time.h>
33 #include <asm/open_pic.h>
34 #include <asm/machdep.h>
35
36 extern unsigned long smp_chrp_cpu_nr;
37
38 static int __init
39 smp_chrp_probe(void)
40 {
41         if (smp_chrp_cpu_nr > 1)
42                 openpic_request_IPIs();
43
44         return smp_chrp_cpu_nr;
45 }
46
47 static void __devinit
48 smp_chrp_kick_cpu(int nr)
49 {
50         *(unsigned long *)KERNELBASE = nr;
51         asm volatile("dcbf 0,%0"::"r"(KERNELBASE):"memory");
52 }
53
54 static void __devinit
55 smp_chrp_setup_cpu(int cpu_nr)
56 {
57         if (OpenPIC_Addr)
58                 do_openpic_setup_cpu();
59 }
60
61 static DEFINE_SPINLOCK(timebase_lock);
62 static unsigned int timebase_upper = 0, timebase_lower = 0;
63
64 void __devinit
65 smp_chrp_give_timebase(void)
66 {
67         spin_lock(&timebase_lock);
68         call_rtas("freeze-time-base", 0, 1, NULL);
69         timebase_upper = get_tbu();
70         timebase_lower = get_tbl();
71         spin_unlock(&timebase_lock);
72
73         while (timebase_upper || timebase_lower)
74                 barrier();
75         call_rtas("thaw-time-base", 0, 1, NULL);
76 }
77
78 void __devinit
79 smp_chrp_take_timebase(void)
80 {
81         while (!(timebase_upper || timebase_lower))
82                 barrier();
83         spin_lock(&timebase_lock);
84         set_tb(timebase_upper, timebase_lower);
85         timebase_upper = 0;
86         timebase_lower = 0;
87         spin_unlock(&timebase_lock);
88         printk("CPU %i taken timebase\n", smp_processor_id());
89 }
90
91 /* CHRP with openpic */
92 struct smp_ops_t chrp_smp_ops = {
93         .message_pass = smp_openpic_message_pass,
94         .probe = smp_chrp_probe,
95         .kick_cpu = smp_chrp_kick_cpu,
96         .setup_cpu = smp_chrp_setup_cpu,
97         .give_timebase = smp_chrp_give_timebase,
98         .take_timebase = smp_chrp_take_timebase,
99 };