Merge branch 'master' of git://git.infradead.org/users/pcmoore/selinux into next
[linux-2.6-microblaze.git] / drivers / cpufreq / cris-artpec3-cpufreq.c
1 #include <linux/init.h>
2 #include <linux/module.h>
3 #include <linux/cpufreq.h>
4 #include <hwregs/reg_map.h>
5 #include <hwregs/reg_rdwr.h>
6 #include <hwregs/clkgen_defs.h>
7 #include <hwregs/ddr2_defs.h>
8
9 static int
10 cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
11         void *data);
12
13 static struct notifier_block cris_sdram_freq_notifier_block = {
14         .notifier_call = cris_sdram_freq_notifier
15 };
16
17 static struct cpufreq_frequency_table cris_freq_table[] = {
18         {0x01,  6000},
19         {0x02,  200000},
20         {0,     CPUFREQ_TABLE_END},
21 };
22
23 static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
24 {
25         reg_clkgen_rw_clk_ctrl clk_ctrl;
26         clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
27         return clk_ctrl.pll ? 200000 : 6000;
28 }
29
30 static int cris_freq_target(struct cpufreq_policy *policy, unsigned int state)
31 {
32         reg_clkgen_rw_clk_ctrl clk_ctrl;
33         clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
34
35         local_irq_disable();
36
37         /* Even though we may be SMP they will share the same clock
38          * so all settings are made on CPU0. */
39         if (cris_freq_table[state].frequency == 200000)
40                 clk_ctrl.pll = 1;
41         else
42                 clk_ctrl.pll = 0;
43         REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);
44
45         local_irq_enable();
46
47         return 0;
48 }
49
50 static int cris_freq_cpu_init(struct cpufreq_policy *policy)
51 {
52         return cpufreq_generic_init(policy, cris_freq_table, 1000000);
53 }
54
55 static struct cpufreq_driver cris_freq_driver = {
56         .get    = cris_freq_get_cpu_frequency,
57         .verify = cpufreq_generic_frequency_table_verify,
58         .target_index = cris_freq_target,
59         .init   = cris_freq_cpu_init,
60         .exit   = cpufreq_generic_exit,
61         .name   = "cris_freq",
62         .attr   = cpufreq_generic_attr,
63 };
64
65 static int __init cris_freq_init(void)
66 {
67         int ret;
68         ret = cpufreq_register_driver(&cris_freq_driver);
69         cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
70                 CPUFREQ_TRANSITION_NOTIFIER);
71         return ret;
72 }
73
74 static int
75 cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
76         void *data)
77 {
78         int i;
79         struct cpufreq_freqs *freqs = data;
80         if (val == CPUFREQ_PRECHANGE) {
81                 reg_ddr2_rw_cfg cfg =
82                   REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
83                 cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);
84
85                 if (freqs->new == 200000)
86                         for (i = 0; i < 50000; i++);
87                 REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
88         }
89         return 0;
90 }
91
92
93 module_init(cris_freq_init);