diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-20 14:26:56 -0500 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-20 14:26:56 -0500 |
commit | 8793422fd9ac5037f5047f80473007301df3689f (patch) | |
tree | f5aa3b3a564f053e1b5604c45db80193abc734a4 /drivers/cpufreq/kirkwood-cpufreq.c | |
parent | b3cdda2b4f541439ca4205793040aa2e1c852e3b (diff) | |
parent | 10baf04e95fbf7eb6089410220a547211dd2ffa7 (diff) |
Merge tag 'pm+acpi-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
- Rework of the ACPI namespace scanning code from Rafael J. Wysocki
with contributions from Bjorn Helgaas, Jiang Liu, Mika Westerberg,
Toshi Kani, and Yinghai Lu.
- ACPI power resources handling and ACPI device PM update from Rafael
J Wysocki.
- ACPICA update to version 20130117 from Bob Moore and Lv Zheng with
contributions from Aaron Lu, Chao Guan, Jesper Juhl, and Tim Gardner.
- Support for Intel Lynxpoint LPSS from Mika Westerberg.
- cpuidle update from Len Brown including Intel Haswell support, C1
state for intel_idle, removal of global pm_idle.
- cpuidle fixes and cleanups from Daniel Lezcano.
- cpufreq fixes and cleanups from Viresh Kumar and Fabio Baltieri with
contributions from Stratos Karafotis and Rickard Andersson.
- Intel P-states driver for Sandy Bridge processors from Dirk
Brandewie.
- cpufreq driver for Marvell Kirkwood SoCs from Andrew Lunn.
- cpufreq fixes related to ordering issues between acpi-cpufreq and
powernow-k8 from Borislav Petkov and Matthew Garrett.
- cpufreq support for Calxeda Highbank processors from Mark Langsdorf
and Rob Herring.
- cpufreq driver for the Freescale i.MX6Q SoC and cpufreq-cpu0 update
from Shawn Guo.
- cpufreq Exynos fixes and cleanups from Jonghwan Choi, Sachin Kamat,
and Inderpal Singh.
- Support for "lightweight suspend" from Zhang Rui.
- Removal of the deprecated power trace API from Paul Gortmaker.
- Assorted updates from Andreas Fleig, Colin Ian King, Davidlohr Bueso,
Joseph Salisbury, Kees Cook, Li Fei, Nishanth Menon, ShuoX Liu,
Srinivas Pandruvada, Tejun Heo, Thomas Renninger, and Yasuaki
Ishimatsu.
* tag 'pm+acpi-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (267 commits)
PM idle: remove global declaration of pm_idle
unicore32 idle: delete stray pm_idle comment
openrisc idle: delete pm_idle
mn10300 idle: delete pm_idle
microblaze idle: delete pm_idle
m32r idle: delete pm_idle, and other dead idle code
ia64 idle: delete pm_idle
cris idle: delete idle and pm_idle
ARM64 idle: delete pm_idle
ARM idle: delete pm_idle
blackfin idle: delete pm_idle
sparc idle: rename pm_idle to sparc_idle
sh idle: rename global pm_idle to static sh_idle
x86 idle: rename global pm_idle to static x86_idle
APM idle: register apm_cpu_idle via cpuidle
cpufreq / intel_pstate: Add kernel command line option disable intel_pstate.
cpufreq / intel_pstate: Change to disallow module build
tools/power turbostat: display SMI count by default
intel_idle: export both C1 and C1E
ACPI / hotplug: Fix concurrency issues and memory leaks
...
Diffstat (limited to 'drivers/cpufreq/kirkwood-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/kirkwood-cpufreq.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/cpufreq/kirkwood-cpufreq.c b/drivers/cpufreq/kirkwood-cpufreq.c new file mode 100644 index 000000000000..0e83e3c24f5b --- /dev/null +++ b/drivers/cpufreq/kirkwood-cpufreq.c | |||
@@ -0,0 +1,259 @@ | |||
1 | /* | ||
2 | * kirkwood_freq.c: cpufreq driver for the Marvell kirkwood | ||
3 | * | ||
4 | * Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch> | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public License | ||
8 | * as published by the Free Software Foundation; either version | ||
9 | * 2 of the License, or (at your option) any later version. | ||
10 | */ | ||
11 | |||
12 | #include <linux/kernel.h> | ||
13 | #include <linux/module.h> | ||
14 | #include <linux/clk.h> | ||
15 | #include <linux/clk-provider.h> | ||
16 | #include <linux/cpufreq.h> | ||
17 | #include <linux/of.h> | ||
18 | #include <linux/platform_device.h> | ||
19 | #include <linux/io.h> | ||
20 | #include <asm/proc-fns.h> | ||
21 | |||
22 | #define CPU_SW_INT_BLK BIT(28) | ||
23 | |||
24 | static struct priv | ||
25 | { | ||
26 | struct clk *cpu_clk; | ||
27 | struct clk *ddr_clk; | ||
28 | struct clk *powersave_clk; | ||
29 | struct device *dev; | ||
30 | void __iomem *base; | ||
31 | } priv; | ||
32 | |||
33 | #define STATE_CPU_FREQ 0x01 | ||
34 | #define STATE_DDR_FREQ 0x02 | ||
35 | |||
36 | /* | ||
37 | * Kirkwood can swap the clock to the CPU between two clocks: | ||
38 | * | ||
39 | * - cpu clk | ||
40 | * - ddr clk | ||
41 | * | ||
42 | * The frequencies are set at runtime before registering this * | ||
43 | * table. | ||
44 | */ | ||
45 | static struct cpufreq_frequency_table kirkwood_freq_table[] = { | ||
46 | {STATE_CPU_FREQ, 0}, /* CPU uses cpuclk */ | ||
47 | {STATE_DDR_FREQ, 0}, /* CPU uses ddrclk */ | ||
48 | {0, CPUFREQ_TABLE_END}, | ||
49 | }; | ||
50 | |||
51 | static unsigned int kirkwood_cpufreq_get_cpu_frequency(unsigned int cpu) | ||
52 | { | ||
53 | if (__clk_is_enabled(priv.powersave_clk)) | ||
54 | return kirkwood_freq_table[1].frequency; | ||
55 | return kirkwood_freq_table[0].frequency; | ||
56 | } | ||
57 | |||
58 | static void kirkwood_cpufreq_set_cpu_state(unsigned int index) | ||
59 | { | ||
60 | struct cpufreq_freqs freqs; | ||
61 | unsigned int state = kirkwood_freq_table[index].index; | ||
62 | unsigned long reg; | ||
63 | |||
64 | freqs.old = kirkwood_cpufreq_get_cpu_frequency(0); | ||
65 | freqs.new = kirkwood_freq_table[index].frequency; | ||
66 | freqs.cpu = 0; /* Kirkwood is UP */ | ||
67 | |||
68 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | ||
69 | |||
70 | dev_dbg(priv.dev, "Attempting to set frequency to %i KHz\n", | ||
71 | kirkwood_freq_table[index].frequency); | ||
72 | dev_dbg(priv.dev, "old frequency was %i KHz\n", | ||
73 | kirkwood_cpufreq_get_cpu_frequency(0)); | ||
74 | |||
75 | if (freqs.old != freqs.new) { | ||
76 | local_irq_disable(); | ||
77 | |||
78 | /* Disable interrupts to the CPU */ | ||
79 | reg = readl_relaxed(priv.base); | ||
80 | reg |= CPU_SW_INT_BLK; | ||
81 | writel_relaxed(reg, priv.base); | ||
82 | |||
83 | switch (state) { | ||
84 | case STATE_CPU_FREQ: | ||
85 | clk_disable(priv.powersave_clk); | ||
86 | break; | ||
87 | case STATE_DDR_FREQ: | ||
88 | clk_enable(priv.powersave_clk); | ||
89 | break; | ||
90 | } | ||
91 | |||
92 | /* Wait-for-Interrupt, while the hardware changes frequency */ | ||
93 | cpu_do_idle(); | ||
94 | |||
95 | /* Enable interrupts to the CPU */ | ||
96 | reg = readl_relaxed(priv.base); | ||
97 | reg &= ~CPU_SW_INT_BLK; | ||
98 | writel_relaxed(reg, priv.base); | ||
99 | |||
100 | local_irq_enable(); | ||
101 | } | ||
102 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | ||
103 | }; | ||
104 | |||
105 | static int kirkwood_cpufreq_verify(struct cpufreq_policy *policy) | ||
106 | { | ||
107 | return cpufreq_frequency_table_verify(policy, kirkwood_freq_table); | ||
108 | } | ||
109 | |||
110 | static int kirkwood_cpufreq_target(struct cpufreq_policy *policy, | ||
111 | unsigned int target_freq, | ||
112 | unsigned int relation) | ||
113 | { | ||
114 | unsigned int index = 0; | ||
115 | |||
116 | if (cpufreq_frequency_table_target(policy, kirkwood_freq_table, | ||
117 | target_freq, relation, &index)) | ||
118 | return -EINVAL; | ||
119 | |||
120 | kirkwood_cpufreq_set_cpu_state(index); | ||
121 | |||
122 | return 0; | ||
123 | } | ||
124 | |||
125 | /* Module init and exit code */ | ||
126 | static int kirkwood_cpufreq_cpu_init(struct cpufreq_policy *policy) | ||
127 | { | ||
128 | int result; | ||
129 | |||
130 | /* cpuinfo and default policy values */ | ||
131 | policy->cpuinfo.transition_latency = 5000; /* 5uS */ | ||
132 | policy->cur = kirkwood_cpufreq_get_cpu_frequency(0); | ||
133 | |||
134 | result = cpufreq_frequency_table_cpuinfo(policy, kirkwood_freq_table); | ||
135 | if (result) | ||
136 | return result; | ||
137 | |||
138 | cpufreq_frequency_table_get_attr(kirkwood_freq_table, policy->cpu); | ||
139 | |||
140 | return 0; | ||
141 | } | ||
142 | |||
143 | static int kirkwood_cpufreq_cpu_exit(struct cpufreq_policy *policy) | ||
144 | { | ||
145 | cpufreq_frequency_table_put_attr(policy->cpu); | ||
146 | return 0; | ||
147 | } | ||
148 | |||
149 | static struct freq_attr *kirkwood_cpufreq_attr[] = { | ||
150 | &cpufreq_freq_attr_scaling_available_freqs, | ||
151 | NULL, | ||
152 | }; | ||
153 | |||
154 | static struct cpufreq_driver kirkwood_cpufreq_driver = { | ||
155 | .get = kirkwood_cpufreq_get_cpu_frequency, | ||
156 | .verify = kirkwood_cpufreq_verify, | ||
157 | .target = kirkwood_cpufreq_target, | ||
158 | .init = kirkwood_cpufreq_cpu_init, | ||
159 | .exit = kirkwood_cpufreq_cpu_exit, | ||
160 | .name = "kirkwood-cpufreq", | ||
161 | .owner = THIS_MODULE, | ||
162 | .attr = kirkwood_cpufreq_attr, | ||
163 | }; | ||
164 | |||
165 | static int kirkwood_cpufreq_probe(struct platform_device *pdev) | ||
166 | { | ||
167 | struct device_node *np; | ||
168 | struct resource *res; | ||
169 | int err; | ||
170 | |||
171 | priv.dev = &pdev->dev; | ||
172 | |||
173 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
174 | if (!res) { | ||
175 | dev_err(&pdev->dev, "Cannot get memory resource\n"); | ||
176 | return -ENODEV; | ||
177 | } | ||
178 | priv.base = devm_request_and_ioremap(&pdev->dev, res); | ||
179 | if (!priv.base) { | ||
180 | dev_err(&pdev->dev, "Cannot ioremap\n"); | ||
181 | return -EADDRNOTAVAIL; | ||
182 | } | ||
183 | |||
184 | np = of_find_node_by_path("/cpus/cpu@0"); | ||
185 | if (!np) | ||
186 | return -ENODEV; | ||
187 | |||
188 | priv.cpu_clk = of_clk_get_by_name(np, "cpu_clk"); | ||
189 | if (IS_ERR(priv.cpu_clk)) { | ||
190 | dev_err(priv.dev, "Unable to get cpuclk"); | ||
191 | return PTR_ERR(priv.cpu_clk); | ||
192 | } | ||
193 | |||
194 | clk_prepare_enable(priv.cpu_clk); | ||
195 | kirkwood_freq_table[0].frequency = clk_get_rate(priv.cpu_clk) / 1000; | ||
196 | |||
197 | priv.ddr_clk = of_clk_get_by_name(np, "ddrclk"); | ||
198 | if (IS_ERR(priv.ddr_clk)) { | ||
199 | dev_err(priv.dev, "Unable to get ddrclk"); | ||
200 | err = PTR_ERR(priv.ddr_clk); | ||
201 | goto out_cpu; | ||
202 | } | ||
203 | |||
204 | clk_prepare_enable(priv.ddr_clk); | ||
205 | kirkwood_freq_table[1].frequency = clk_get_rate(priv.ddr_clk) / 1000; | ||
206 | |||
207 | priv.powersave_clk = of_clk_get_by_name(np, "powersave"); | ||
208 | if (IS_ERR(priv.powersave_clk)) { | ||
209 | dev_err(priv.dev, "Unable to get powersave"); | ||
210 | err = PTR_ERR(priv.powersave_clk); | ||
211 | goto out_ddr; | ||
212 | } | ||
213 | clk_prepare(priv.powersave_clk); | ||
214 | |||
215 | of_node_put(np); | ||
216 | np = NULL; | ||
217 | |||
218 | err = cpufreq_register_driver(&kirkwood_cpufreq_driver); | ||
219 | if (!err) | ||
220 | return 0; | ||
221 | |||
222 | dev_err(priv.dev, "Failed to register cpufreq driver"); | ||
223 | |||
224 | clk_disable_unprepare(priv.powersave_clk); | ||
225 | out_ddr: | ||
226 | clk_disable_unprepare(priv.ddr_clk); | ||
227 | out_cpu: | ||
228 | clk_disable_unprepare(priv.cpu_clk); | ||
229 | of_node_put(np); | ||
230 | |||
231 | return err; | ||
232 | } | ||
233 | |||
234 | static int kirkwood_cpufreq_remove(struct platform_device *pdev) | ||
235 | { | ||
236 | cpufreq_unregister_driver(&kirkwood_cpufreq_driver); | ||
237 | |||
238 | clk_disable_unprepare(priv.powersave_clk); | ||
239 | clk_disable_unprepare(priv.ddr_clk); | ||
240 | clk_disable_unprepare(priv.cpu_clk); | ||
241 | |||
242 | return 0; | ||
243 | } | ||
244 | |||
245 | static struct platform_driver kirkwood_cpufreq_platform_driver = { | ||
246 | .probe = kirkwood_cpufreq_probe, | ||
247 | .remove = kirkwood_cpufreq_remove, | ||
248 | .driver = { | ||
249 | .name = "kirkwood-cpufreq", | ||
250 | .owner = THIS_MODULE, | ||
251 | }, | ||
252 | }; | ||
253 | |||
254 | module_platform_driver(kirkwood_cpufreq_platform_driver); | ||
255 | |||
256 | MODULE_LICENSE("GPL v2"); | ||
257 | MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch"); | ||
258 | MODULE_DESCRIPTION("cpufreq driver for Marvell's kirkwood CPU"); | ||
259 | MODULE_ALIAS("platform:kirkwood-cpufreq"); | ||