Merge git://git.infradead.org/battery-2.6
[linux-2.6] / arch / mips / oprofile / op_model_rm9000.c
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2004 by Ralf Baechle
7  */
8 #include <linux/init.h>
9 #include <linux/oprofile.h>
10 #include <linux/interrupt.h>
11 #include <linux/smp.h>
12
13 #include "op_impl.h"
14
15 #define RM9K_COUNTER1_EVENT(event)      ((event) << 0)
16 #define RM9K_COUNTER1_SUPERVISOR        (1ULL    <<  7)
17 #define RM9K_COUNTER1_KERNEL            (1ULL    <<  8)
18 #define RM9K_COUNTER1_USER              (1ULL    <<  9)
19 #define RM9K_COUNTER1_ENABLE            (1ULL    << 10)
20 #define RM9K_COUNTER1_OVERFLOW          (1ULL    << 15)
21
22 #define RM9K_COUNTER2_EVENT(event)      ((event) << 16)
23 #define RM9K_COUNTER2_SUPERVISOR        (1ULL    << 23)
24 #define RM9K_COUNTER2_KERNEL            (1ULL    << 24)
25 #define RM9K_COUNTER2_USER              (1ULL    << 25)
26 #define RM9K_COUNTER2_ENABLE            (1ULL    << 26)
27 #define RM9K_COUNTER2_OVERFLOW          (1ULL    << 31)
28
29 extern unsigned int rm9000_perfcount_irq;
30
31 static struct rm9k_register_config {
32         unsigned int control;
33         unsigned int reset_counter1;
34         unsigned int reset_counter2;
35 } reg;
36
37 /* Compute all of the registers in preparation for enabling profiling.  */
38
39 static void rm9000_reg_setup(struct op_counter_config *ctr)
40 {
41         unsigned int control = 0;
42
43         /* Compute the performance counter control word.  */
44         /* For now count kernel and user mode */
45         if (ctr[0].enabled)
46                 control |= RM9K_COUNTER1_EVENT(ctr[0].event) |
47                            RM9K_COUNTER1_KERNEL |
48                            RM9K_COUNTER1_USER |
49                            RM9K_COUNTER1_ENABLE;
50         if (ctr[1].enabled)
51                 control |= RM9K_COUNTER2_EVENT(ctr[1].event) |
52                            RM9K_COUNTER2_KERNEL |
53                            RM9K_COUNTER2_USER |
54                            RM9K_COUNTER2_ENABLE;
55         reg.control = control;
56
57         reg.reset_counter1 = 0x80000000 - ctr[0].count;
58         reg.reset_counter2 = 0x80000000 - ctr[1].count;
59 }
60
61 /* Program all of the registers in preparation for enabling profiling.  */
62
63 static void rm9000_cpu_setup (void *args)
64 {
65         uint64_t perfcount;
66
67         perfcount = ((uint64_t) reg.reset_counter2 << 32) | reg.reset_counter1;
68         write_c0_perfcount(perfcount);
69 }
70
71 static void rm9000_cpu_start(void *args)
72 {
73         /* Start all counters on current CPU */
74         write_c0_perfcontrol(reg.control);
75 }
76
77 static void rm9000_cpu_stop(void *args)
78 {
79         /* Stop all counters on current CPU */
80         write_c0_perfcontrol(0);
81 }
82
83 static irqreturn_t rm9000_perfcount_handler(int irq, void * dev_id)
84 {
85         unsigned int control = read_c0_perfcontrol();
86         struct pt_regs *regs = get_irq_regs();
87         uint32_t counter1, counter2;
88         uint64_t counters;
89
90         /*
91          * RM9000 combines two 32-bit performance counters into a single
92          * 64-bit coprocessor zero register.  To avoid a race updating the
93          * registers we need to stop the counters while we're messing with
94          * them ...
95          */
96         write_c0_perfcontrol(0);
97
98         counters = read_c0_perfcount();
99         counter1 = counters;
100         counter2 = counters >> 32;
101
102         if (control & RM9K_COUNTER1_OVERFLOW) {
103                 oprofile_add_sample(regs, 0);
104                 counter1 = reg.reset_counter1;
105         }
106         if (control & RM9K_COUNTER2_OVERFLOW) {
107                 oprofile_add_sample(regs, 1);
108                 counter2 = reg.reset_counter2;
109         }
110
111         counters = ((uint64_t)counter2 << 32) | counter1;
112         write_c0_perfcount(counters);
113         write_c0_perfcontrol(reg.control);
114
115         return IRQ_HANDLED;
116 }
117
118 static int __init rm9000_init(void)
119 {
120         return request_irq(rm9000_perfcount_irq, rm9000_perfcount_handler,
121                            0, "Perfcounter", NULL);
122 }
123
124 static void rm9000_exit(void)
125 {
126         free_irq(rm9000_perfcount_irq, NULL);
127 }
128
129 struct op_mips_model op_model_rm9000_ops = {
130         .reg_setup      = rm9000_reg_setup,
131         .cpu_setup      = rm9000_cpu_setup,
132         .init           = rm9000_init,
133         .exit           = rm9000_exit,
134         .cpu_start      = rm9000_cpu_start,
135         .cpu_stop       = rm9000_cpu_stop,
136         .cpu_type       = "mips/rm9000",
137         .num_counters   = 2
138 };