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-rw-r--r--arch/mips/include/asm/clock.h64
-rw-r--r--arch/mips/include/asm/cpu.h2
-rw-r--r--arch/mips/include/asm/mach-loongson/loongson.h6
-rw-r--r--arch/mips/kernel/Makefile2
-rw-r--r--arch/mips/kernel/cpu-probe.c2
-rw-r--r--arch/mips/kernel/cpufreq/Kconfig14
-rw-r--r--arch/mips/kernel/cpufreq/Makefile5
-rw-r--r--arch/mips/kernel/cpufreq/loongson2_clock.c166
-rw-r--r--arch/mips/kernel/cpufreq/loongson2_cpufreq.c227
-rw-r--r--arch/mips/loongson/Kconfig5
-rw-r--r--arch/mips/loongson/common/Makefile2
-rw-r--r--arch/mips/loongson/common/env.c3
-rw-r--r--arch/mips/loongson/common/platform.c30
13 files changed, 524 insertions, 4 deletions
diff --git a/arch/mips/include/asm/clock.h b/arch/mips/include/asm/clock.h
new file mode 100644
index 000000000000..83894aa7932c
--- /dev/null
+++ b/arch/mips/include/asm/clock.h
@@ -0,0 +1,64 @@
+#ifndef __ASM_MIPS_CLOCK_H
+#define __ASM_MIPS_CLOCK_H
+
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/seq_file.h>
+#include <linux/clk.h>
+
+extern void (*cpu_wait) (void);
+
+struct clk;
+
+struct clk_ops {
+ void (*init) (struct clk *clk);
+ void (*enable) (struct clk *clk);
+ void (*disable) (struct clk *clk);
+ void (*recalc) (struct clk *clk);
+ int (*set_rate) (struct clk *clk, unsigned long rate, int algo_id);
+ long (*round_rate) (struct clk *clk, unsigned long rate);
+};
+
+struct clk {
+ struct list_head node;
+ const char *name;
+ int id;
+ struct module *owner;
+
+ struct clk *parent;
+ struct clk_ops *ops;
+
+ struct kref kref;
+
+ unsigned long rate;
+ unsigned long flags;
+};
+
+#define CLK_ALWAYS_ENABLED (1 << 0)
+#define CLK_RATE_PROPAGATES (1 << 1)
+
+/* Should be defined by processor-specific code */
+void arch_init_clk_ops(struct clk_ops **, int type);
+
+int clk_init(void);
+
+int __clk_enable(struct clk *);
+void __clk_disable(struct clk *);
+
+void clk_recalc_rate(struct clk *);
+
+int clk_register(struct clk *);
+void clk_unregister(struct clk *);
+
+/* the exported API, in addition to clk_set_rate */
+/**
+ * clk_set_rate_ex - set the clock rate for a clock source, with additional parameter
+ * @clk: clock source
+ * @rate: desired clock rate in Hz
+ * @algo_id: algorithm id to be passed down to ops->set_rate
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id);
+
+#endif /* __ASM_MIPS_CLOCK_H */
diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index 4b96d1a36056..cf373a95fe4a 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -154,6 +154,8 @@
#define PRID_REV_VR4181A 0x0070 /* Same as VR4122 */
#define PRID_REV_VR4130 0x0080
#define PRID_REV_34K_V1_0_2 0x0022
+#define PRID_REV_LOONGSON2E 0x0002
+#define PRID_REV_LOONGSON2F 0x0003
/*
* Older processors used to encode processor version and revision in two
diff --git a/arch/mips/include/asm/mach-loongson/loongson.h b/arch/mips/include/asm/mach-loongson/loongson.h
index 9bccdb5d4b51..a7fa66e85988 100644
--- a/arch/mips/include/asm/mach-loongson/loongson.h
+++ b/arch/mips/include/asm/mach-loongson/loongson.h
@@ -226,8 +226,12 @@ extern void mach_irq_dispatch(unsigned int pending);
#define LOONGSON_PCIMAP_WIN(WIN, ADDR) \
((((ADDR)>>26) & LOONGSON_PCIMAP_PCIMAP_LO0) << ((WIN)*6))
-/* Chip Config */
#ifdef CONFIG_CPU_SUPPORTS_CPUFREQ
+#include <linux/cpufreq.h>
+extern void loongson2_cpu_wait(void);
+extern struct cpufreq_frequency_table loongson2_clockmod_table[];
+
+/* Chip Config */
#define LOONGSON_CHIPCFG0 LOONGSON_REG(LOONGSON_REGBASE + 0x80)
#endif
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index a446aa20ac83..f442de804d8a 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -93,4 +93,6 @@ CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(KBUILD_CFLAGS) -Wa,-mdaddi -c -o /dev/n
obj-$(CONFIG_HAVE_STD_PC_SERIAL_PORT) += 8250-platform.o
+obj-$(CONFIG_MIPS_CPUFREQ) += cpufreq/
+
EXTRA_CFLAGS += -Werror
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 7a51866068a4..80e202eca056 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -16,6 +16,7 @@
#include <linux/ptrace.h>
#include <linux/smp.h>
#include <linux/stddef.h>
+#include <linux/module.h>
#include <asm/bugs.h>
#include <asm/cpu.h>
@@ -32,6 +33,7 @@
* the CPU very much.
*/
void (*cpu_wait)(void);
+EXPORT_SYMBOL(cpu_wait);
static void r3081_wait(void)
{
diff --git a/arch/mips/kernel/cpufreq/Kconfig b/arch/mips/kernel/cpufreq/Kconfig
index 37983a15dabe..58c601eee6fd 100644
--- a/arch/mips/kernel/cpufreq/Kconfig
+++ b/arch/mips/kernel/cpufreq/Kconfig
@@ -20,6 +20,20 @@ if CPU_FREQ
comment "CPUFreq processor drivers"
+config LOONGSON2_CPUFREQ
+ tristate "Loongson2 CPUFreq Driver"
+ select CPU_FREQ_TABLE
+ depends on MIPS_CPUFREQ
+ help
+ This option adds a CPUFreq driver for loongson processors which
+ support software configurable cpu frequency.
+
+ Loongson2F and it's successors support this feature.
+
+ For details, take a look at <file:Documentation/cpu-freq/>.
+
+ If in doubt, say N.
+
endif # CPU_FREQ
endmenu
diff --git a/arch/mips/kernel/cpufreq/Makefile b/arch/mips/kernel/cpufreq/Makefile
new file mode 100644
index 000000000000..c3479a432efe
--- /dev/null
+++ b/arch/mips/kernel/cpufreq/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the Linux/MIPS cpufreq.
+#
+
+obj-$(CONFIG_LOONGSON2_CPUFREQ) += loongson2_cpufreq.o loongson2_clock.o
diff --git a/arch/mips/kernel/cpufreq/loongson2_clock.c b/arch/mips/kernel/cpufreq/loongson2_clock.c
new file mode 100644
index 000000000000..d7ca256e33ef
--- /dev/null
+++ b/arch/mips/kernel/cpufreq/loongson2_clock.c
@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2006 - 2008 Lemote Inc. & Insititute of Computing Technology
+ * Author: Yanhua, yanh@lemote.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/platform_device.h>
+
+#include <asm/clock.h>
+
+#include <loongson.h>
+
+static LIST_HEAD(clock_list);
+static DEFINE_SPINLOCK(clock_lock);
+static DEFINE_MUTEX(clock_list_sem);
+
+/* Minimum CLK support */
+enum {
+ DC_ZERO, DC_25PT = 2, DC_37PT, DC_50PT, DC_62PT, DC_75PT,
+ DC_87PT, DC_DISABLE, DC_RESV
+};
+
+struct cpufreq_frequency_table loongson2_clockmod_table[] = {
+ {DC_RESV, CPUFREQ_ENTRY_INVALID},
+ {DC_ZERO, CPUFREQ_ENTRY_INVALID},
+ {DC_25PT, 0},
+ {DC_37PT, 0},
+ {DC_50PT, 0},
+ {DC_62PT, 0},
+ {DC_75PT, 0},
+ {DC_87PT, 0},
+ {DC_DISABLE, 0},
+ {DC_RESV, CPUFREQ_TABLE_END},
+};
+EXPORT_SYMBOL_GPL(loongson2_clockmod_table);
+
+static struct clk cpu_clk = {
+ .name = "cpu_clk",
+ .flags = CLK_ALWAYS_ENABLED | CLK_RATE_PROPAGATES,
+ .rate = 800000000,
+};
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+ return &cpu_clk;
+}
+EXPORT_SYMBOL(clk_get);
+
+static void propagate_rate(struct clk *clk)
+{
+ struct clk *clkp;
+
+ list_for_each_entry(clkp, &clock_list, node) {
+ if (likely(clkp->parent != clk))
+ continue;
+ if (likely(clkp->ops && clkp->ops->recalc))
+ clkp->ops->recalc(clkp);
+ if (unlikely(clkp->flags & CLK_RATE_PROPAGATES))
+ propagate_rate(clkp);
+ }
+}
+
+int clk_enable(struct clk *clk)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return (unsigned long)clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+void clk_put(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_put);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ return clk_set_rate_ex(clk, rate, 0);
+}
+EXPORT_SYMBOL_GPL(clk_set_rate);
+
+int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id)
+{
+ int ret = 0;
+ int regval;
+ int i;
+
+ if (likely(clk->ops && clk->ops->set_rate)) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&clock_lock, flags);
+ ret = clk->ops->set_rate(clk, rate, algo_id);
+ spin_unlock_irqrestore(&clock_lock, flags);
+ }
+
+ if (unlikely(clk->flags & CLK_RATE_PROPAGATES))
+ propagate_rate(clk);
+
+ for (i = 0; loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END;
+ i++) {
+ if (loongson2_clockmod_table[i].frequency ==
+ CPUFREQ_ENTRY_INVALID)
+ continue;
+ if (rate == loongson2_clockmod_table[i].frequency)
+ break;
+ }
+ if (rate != loongson2_clockmod_table[i].frequency)
+ return -ENOTSUPP;
+
+ clk->rate = rate;
+
+ regval = LOONGSON_CHIPCFG0;
+ regval = (regval & ~0x7) | (loongson2_clockmod_table[i].index - 1);
+ LOONGSON_CHIPCFG0 = regval;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate_ex);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ if (likely(clk->ops && clk->ops->round_rate)) {
+ unsigned long flags, rounded;
+
+ spin_lock_irqsave(&clock_lock, flags);
+ rounded = clk->ops->round_rate(clk, rate);
+ spin_unlock_irqrestore(&clock_lock, flags);
+
+ return rounded;
+ }
+
+ return rate;
+}
+EXPORT_SYMBOL_GPL(clk_round_rate);
+
+/*
+ * This is the simple version of Loongson-2 wait, Maybe we need do this in
+ * interrupt disabled content
+ */
+
+DEFINE_SPINLOCK(loongson2_wait_lock);
+void loongson2_cpu_wait(void)
+{
+ u32 cpu_freq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&loongson2_wait_lock, flags);
+ cpu_freq = LOONGSON_CHIPCFG0;
+ LOONGSON_CHIPCFG0 &= ~0x7; /* Put CPU into wait mode */
+ LOONGSON_CHIPCFG0 = cpu_freq; /* Restore CPU state */
+ spin_unlock_irqrestore(&loongson2_wait_lock, flags);
+}
+EXPORT_SYMBOL_GPL(loongson2_cpu_wait);
diff --git a/arch/mips/kernel/cpufreq/loongson2_cpufreq.c b/arch/mips/kernel/cpufreq/loongson2_cpufreq.c
new file mode 100644
index 000000000000..2f6a0b147ab8
--- /dev/null
+++ b/arch/mips/kernel/cpufreq/loongson2_cpufreq.c
@@ -0,0 +1,227 @@
+/*
+ * Cpufreq driver for the loongson-2 processors
+ *
+ * The 2E revision of loongson processor not support this feature.
+ *
+ * Copyright (C) 2006 - 2008 Lemote Inc. & Insititute of Computing Technology
+ * Author: Yanhua, yanh@lemote.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/sched.h> /* set_cpus_allowed() */
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#include <asm/clock.h>
+
+#include <loongson.h>
+
+static uint nowait;
+
+static struct clk *cpuclk;
+
+static void (*saved_cpu_wait) (void);
+
+static int loongson2_cpu_freq_notifier(struct notifier_block *nb,
+ unsigned long val, void *data);
+
+static struct notifier_block loongson2_cpufreq_notifier_block = {
+ .notifier_call = loongson2_cpu_freq_notifier
+};
+
+static int loongson2_cpu_freq_notifier(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ if (val == CPUFREQ_POSTCHANGE)
+ current_cpu_data.udelay_val = loops_per_jiffy;
+
+ return 0;
+}
+
+static unsigned int loongson2_cpufreq_get(unsigned int cpu)
+{
+ return clk_get_rate(cpuclk);
+}
+
+/*
+ * Here we notify other drivers of the proposed change and the final change.
+ */
+static int loongson2_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int cpu = policy->cpu;
+ unsigned int newstate = 0;
+ cpumask_t cpus_allowed;
+ struct cpufreq_freqs freqs;
+ unsigned int freq;
+
+ if (!cpu_online(cpu))
+ return -ENODEV;
+
+ cpus_allowed = current->cpus_allowed;
+ set_cpus_allowed(current, cpumask_of_cpu(cpu));
+
+ if (cpufreq_frequency_table_target
+ (policy, &loongson2_clockmod_table[0], target_freq, relation,
+ &newstate))
+ return -EINVAL;
+
+ freq =
+ ((cpu_clock_freq / 1000) *
+ loongson2_clockmod_table[newstate].index) / 8;
+ if (freq < policy->min || freq > policy->max)
+ return -EINVAL;
+
+ pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000);
+
+ freqs.cpu = cpu;
+ freqs.old = loongson2_cpufreq_get(cpu);
+ freqs.new = freq;
+ freqs.flags = 0;
+
+ if (freqs.new == freqs.old)
+ return 0;
+
+ /* notifiers */
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ set_cpus_allowed(current, cpus_allowed);
+
+ /* setting the cpu frequency */
+ clk_set_rate(cpuclk, freq);
+
+ /* notifiers */
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ pr_debug("cpufreq: set frequency %u kHz\n", freq);
+
+ return 0;
+}
+
+static int loongson2_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ int i;
+
+ if (!cpu_online(policy->cpu))
+ return -ENODEV;
+
+ cpuclk = clk_get(NULL, "cpu_clk");
+ if (IS_ERR(cpuclk)) {
+ printk(KERN_ERR "cpufreq: couldn't get CPU clk\n");
+ return PTR_ERR(cpuclk);
+ }
+
+ cpuclk->rate = cpu_clock_freq / 1000;
+ if (!cpuclk->rate)
+ return -EINVAL;
+
+ /* clock table init */
+ for (i = 2;
+ (loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END);
+ i++)
+ loongson2_clockmod_table[i].frequency = (cpuclk->rate * i) / 8;
+
+ policy->cur = loongson2_cpufreq_get(policy->cpu);
+
+ cpufreq_frequency_table_get_attr(&loongson2_clockmod_table[0],
+ policy->cpu);
+
+ return cpufreq_frequency_table_cpuinfo(policy,
+ &loongson2_clockmod_table[0]);
+}
+
+static int loongson2_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy,
+ &loongson2_clockmod_table[0]);
+}
+
+static int loongson2_cpufreq_exit(struct cpufreq_policy *policy)
+{
+ clk_put(cpuclk);
+ return 0;
+}
+
+static struct freq_attr *loongson2_table_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver loongson2_cpufreq_driver = {
+ .owner = THIS_MODULE,
+ .name = "loongson2",
+ .init = loongson2_cpufreq_cpu_init,
+ .verify = loongson2_cpufreq_verify,
+ .target = loongson2_cpufreq_target,
+ .get = loongson2_cpufreq_get,
+ .exit = loongson2_cpufreq_exit,
+ .attr = loongson2_table_attr,
+};
+
+static struct platform_device_id platform_device_ids[] = {
+ {
+ .name = "loongson2_cpufreq",
+ },
+ {}
+};
+
+MODULE_DEVICE_TABLE(platform, platform_device_ids);
+
+static struct platform_driver platform_driver = {
+ .driver = {
+ .name = "loongson2_cpufreq",
+ .owner = THIS_MODULE,
+ },
+ .id_table = platform_device_ids,
+};
+
+static int __init cpufreq_init(void)
+{
+ int ret;
+
+ /* Register platform stuff */
+ ret = platform_driver_register(&platform_driver);
+ if (ret)
+ return ret;
+
+ pr_info("cpufreq: Loongson-2F CPU frequency driver.\n");
+
+ cpufreq_register_notifier(&loongson2_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ ret = cpufreq_register_driver(&loongson2_cpufreq_driver);
+
+ if (!ret && !nowait) {
+ saved_cpu_wait = cpu_wait;
+ cpu_wait = loongson2_cpu_wait;
+ }
+
+ return ret;
+}
+
+static void __exit cpufreq_exit(void)
+{
+ if (!nowait && saved_cpu_wait)
+ cpu_wait = saved_cpu_wait;
+ cpufreq_unregister_driver(&loongson2_cpufreq_driver);
+ cpufreq_unregister_notifier(&loongson2_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ platform_driver_unregister(&platform_driver);
+}
+
+module_init(cpufreq_init);
+module_exit(cpufreq_exit);
+
+module_param(nowait, uint, 0644);
+MODULE_PARM_DESC(nowait, "Disable Loongson-2F specific wait");
+
+MODULE_AUTHOR("Yanhua <yanh@lemote.com>");
+MODULE_DESCRIPTION("cpufreq driver for Loongson2F");
+MODULE_LICENSE("GPL");
diff --git a/arch/mips/loongson/Kconfig b/arch/mips/loongson/Kconfig
index 8b5cc138611a..7a86987b478f 100644
--- a/arch/mips/loongson/Kconfig
+++ b/arch/mips/loongson/Kconfig
@@ -34,10 +34,10 @@ config LEMOTE_MACH2F
select ARCH_SPARSEMEM_ENABLE
select BOARD_SCACHE
select BOOT_ELF32
- select CEVT_R4K
+ select CEVT_R4K if ! MIPS_EXTERNAL_TIMER
select CPU_HAS_WB
select CS5536
- select CSRC_R4K
+ select CSRC_R4K if ! MIPS_EXTERNAL_TIMER
select DMA_NONCOHERENT
select GENERIC_HARDIRQS_NO__DO_IRQ
select GENERIC_ISA_DMA_SUPPORT_BROKEN
@@ -65,6 +65,7 @@ config CS5536
config CS5536_MFGPT
bool "CS5536 MFGPT Timer"
depends on CS5536
+ select MIPS_EXTERNAL_TIMER
help
This option enables the mfgpt0 timer of AMD CS5536.
diff --git a/arch/mips/loongson/common/Makefile b/arch/mips/loongson/common/Makefile
index a21724d50e2c..8d71892413df 100644
--- a/arch/mips/loongson/common/Makefile
+++ b/arch/mips/loongson/common/Makefile
@@ -3,7 +3,7 @@
#
obj-y += setup.o init.o cmdline.o env.o time.o reset.o irq.o \
- pci.o bonito-irq.o mem.o machtype.o uart_base.o
+ pci.o bonito-irq.o mem.o machtype.o platform.o uart_base.o
#
# Early printk support
diff --git a/arch/mips/loongson/common/env.c b/arch/mips/loongson/common/env.c
index b9ef50385541..196d947d929a 100644
--- a/arch/mips/loongson/common/env.c
+++ b/arch/mips/loongson/common/env.c
@@ -17,11 +17,14 @@
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
+#include <linux/module.h>
+
#include <asm/bootinfo.h>
#include <loongson.h>
unsigned long bus_clock, cpu_clock_freq;
+EXPORT_SYMBOL(cpu_clock_freq);
unsigned long memsize, highmemsize;
/* pmon passes arguments in 32bit pointers */
diff --git a/arch/mips/loongson/common/platform.c b/arch/mips/loongson/common/platform.c
new file mode 100644
index 000000000000..be81777eb94d
--- /dev/null
+++ b/arch/mips/loongson/common/platform.c
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2009 Lemote Inc.
+ * Author: Wu Zhangjin, wuzj@lemote.com
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/err.h>
+#include <linux/platform_device.h>
+
+static struct platform_device loongson2_cpufreq_device = {
+ .name = "loongson2_cpufreq",
+ .id = -1,
+};
+
+static int __init loongson2_cpufreq_init(void)
+{
+ struct cpuinfo_mips *c = &current_cpu_data;
+
+ /* Only 2F revision and it's successors support CPUFreq */
+ if ((c->processor_id & PRID_REV_MASK) >= PRID_REV_LOONGSON2F)
+ return platform_device_register(&loongson2_cpufreq_device);
+
+ return -ENODEV;
+}
+
+arch_initcall(loongson2_cpufreq_init);