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authorJesper Nilsson <jespern@stork.se.axis.com>2007-11-29 11:11:23 -0500
committerJesper Nilsson <jesper.nilsson@axis.com>2008-02-08 05:06:23 -0500
commit035e111f9a9b29843bc899f03d56f19d94bebb53 (patch)
treecb46b3c0eb6d9f2cc915522153454d3acaa7fcda /arch/cris/arch-v32/mach-a3/cpufreq.c
parent6107c61fd3e6b47106b078db1726ad814564efef (diff)
CRIS v32: Add new machine dependent files for Etrax-FS and Artpec-3.
The two chips are somewhat different, and needs different handling. Adds handing of the dma, dram initialization, hardware settings, io, memory arbiter and pinmux Also moves the dma, dram initialization and io from CRIS v32 common files.
Diffstat (limited to 'arch/cris/arch-v32/mach-a3/cpufreq.c')
-rw-r--r--arch/cris/arch-v32/mach-a3/cpufreq.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/mach-a3/cpufreq.c b/arch/cris/arch-v32/mach-a3/cpufreq.c
new file mode 100644
index 000000000000..8e5a3cab8ad7
--- /dev/null
+++ b/arch/cris/arch-v32/mach-a3/cpufreq.c
@@ -0,0 +1,153 @@
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
9static int
10cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
11 void *data);
12
13static struct notifier_block cris_sdram_freq_notifier_block = {
14 .notifier_call = cris_sdram_freq_notifier
15};
16
17static struct cpufreq_frequency_table cris_freq_table[] = {
18 {0x01, 6000},
19 {0x02, 200000},
20 {0, CPUFREQ_TABLE_END},
21};
22
23static 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
30static void cris_freq_set_cpu_state(unsigned int state)
31{
32 int i = 0;
33 struct cpufreq_freqs freqs;
34 reg_clkgen_rw_clk_ctrl clk_ctrl;
35 clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
36
37#ifdef CONFIG_SMP
38 for_each_present_cpu(i)
39#endif
40 {
41 freqs.old = cris_freq_get_cpu_frequency(i);
42 freqs.new = cris_freq_table[state].frequency;
43 freqs.cpu = i;
44 }
45
46 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
47
48 local_irq_disable();
49
50 /* Even though we may be SMP they will share the same clock
51 * so all settings are made on CPU0. */
52 if (cris_freq_table[state].frequency == 200000)
53 clk_ctrl.pll = 1;
54 else
55 clk_ctrl.pll = 0;
56 REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);
57
58 local_irq_enable();
59
60 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
61};
62
63static int cris_freq_verify(struct cpufreq_policy *policy)
64{
65 return cpufreq_frequency_table_verify(policy, &cris_freq_table[0]);
66}
67
68static int cris_freq_target(struct cpufreq_policy *policy,
69 unsigned int target_freq,
70 unsigned int relation)
71{
72 unsigned int newstate = 0;
73
74 if (cpufreq_frequency_table_target(policy, cris_freq_table,
75 target_freq, relation, &newstate))
76 return -EINVAL;
77
78 cris_freq_set_cpu_state(newstate);
79
80 return 0;
81}
82
83static int cris_freq_cpu_init(struct cpufreq_policy *policy)
84{
85 int result;
86
87 /* cpuinfo and default policy values */
88 policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
89 policy->cpuinfo.transition_latency = 1000000; /* 1ms */
90 policy->cur = cris_freq_get_cpu_frequency(0);
91
92 result = cpufreq_frequency_table_cpuinfo(policy, cris_freq_table);
93 if (result)
94 return (result);
95
96 cpufreq_frequency_table_get_attr(cris_freq_table, policy->cpu);
97
98 return 0;
99}
100
101
102static int cris_freq_cpu_exit(struct cpufreq_policy *policy)
103{
104 cpufreq_frequency_table_put_attr(policy->cpu);
105 return 0;
106}
107
108
109static struct freq_attr *cris_freq_attr[] = {
110 &cpufreq_freq_attr_scaling_available_freqs,
111 NULL,
112};
113
114static struct cpufreq_driver cris_freq_driver = {
115 .get = cris_freq_get_cpu_frequency,
116 .verify = cris_freq_verify,
117 .target = cris_freq_target,
118 .init = cris_freq_cpu_init,
119 .exit = cris_freq_cpu_exit,
120 .name = "cris_freq",
121 .owner = THIS_MODULE,
122 .attr = cris_freq_attr,
123};
124
125static int __init cris_freq_init(void)
126{
127 int ret;
128 ret = cpufreq_register_driver(&cris_freq_driver);
129 cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
130 CPUFREQ_TRANSITION_NOTIFIER);
131 return ret;
132}
133
134static int
135cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
136 void *data)
137{
138 int i;
139 struct cpufreq_freqs *freqs = data;
140 if (val == CPUFREQ_PRECHANGE) {
141 reg_ddr2_rw_cfg cfg =
142 REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
143 cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);
144
145 if (freqs->new == 200000)
146 for (i = 0; i < 50000; i++);
147 REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
148 }
149 return 0;
150}
151
152
153module_init(cris_freq_init);