@@ -1241,7 +1241,7 @@ endmenu
menu "CPU Power Management"
-if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_PXA || ARCH_S3C64XX)
+if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_PXA || ARCH_S3C64XX || ARCH_DAVINCI_DA8XX)
source "drivers/cpufreq/Kconfig"
@@ -29,3 +29,6 @@ obj-$(CONFIG_MACH_DAVINCI_DM6467_EVM) += board-dm646x-evm.o
obj-$(CONFIG_MACH_DAVINCI_DM365_EVM) += board-dm365-evm.o
obj-$(CONFIG_MACH_DAVINCI_DA830_EVM) += board-da830-evm.o
obj-$(CONFIG_MACH_DAVINCI_DA850_EVM) += board-da850-evm.o
+
+# Power Management
+obj-$(CONFIG_CPU_FREQ) += cpufreq.o
new file mode 100644
@@ -0,0 +1,183 @@
+/*
+ * CPU frequency scaling for DaVinci
+ *
+ * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Based on linux/arch/arm/plat-omap/cpu-omap.c. Original Copyright follows:
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Written by Tony Lindgren <tony@atomide.com>
+ *
+ * Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
+ *
+ * Copyright (C) 2007-2008 Texas Instruments, Inc.
+ * Updated to support OMAP3
+ * Rajendra Nayak <rnayak@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/system.h>
+#include <mach/clock.h>
+#include <mach/common.h>
+
+#include "clock.h"
+
+static struct cpufreq_frequency_table *freq_table;
+static struct clk *armclk;
+
+static int davinci_verify_speed(struct cpufreq_policy *policy)
+{
+ if (freq_table)
+ return cpufreq_frequency_table_verify(policy, freq_table);
+
+ if (policy->cpu)
+ return -EINVAL;
+
+ cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+ policy->cpuinfo.max_freq);
+
+ policy->min = clk_round_rate(armclk, policy->min * 1000) / 1000;
+ policy->max = clk_round_rate(armclk, policy->max * 1000) / 1000;
+ cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+ policy->cpuinfo.max_freq);
+ return 0;
+}
+
+static unsigned int davinci_getspeed(unsigned int cpu)
+{
+ unsigned long rate;
+
+ if (cpu)
+ return 0;
+
+ rate = clk_get_rate(armclk) / 1000;
+
+ return rate;
+}
+
+static int davinci_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ struct cpufreq_freqs freqs;
+ int ret = 0;
+
+ /*
+ * Ensure desired rate is within allowed range. Some govenors
+ * (ondemand) will just pass target_freq=0 to get the minimum.
+ */
+ if (target_freq < policy->cpuinfo.min_freq)
+ target_freq = policy->cpuinfo.min_freq;
+ if (target_freq > policy->cpuinfo.max_freq)
+ target_freq = policy->cpuinfo.max_freq;
+
+ freqs.old = davinci_getspeed(0);
+ freqs.new = clk_round_rate(armclk, target_freq * 1000) / 1000;
+ freqs.cpu = 0;
+
+ if (freqs.old == freqs.new)
+ return ret;
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+#ifdef CONFIG_CPU_FREQ_DEBUG
+ printk(KERN_DEBUG "cpufreq-davinci: transition: %u --> %u\n",
+ freqs.old, freqs.new);
+#endif
+ ret = clk_set_rate(armclk, freqs.new * 1000);
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ return ret;
+}
+
+static int __init davinci_cpu_init(struct cpufreq_policy *policy)
+{
+ int result = 0;
+
+ armclk = clk_get(NULL, "arm");
+ if (IS_ERR(armclk)) {
+ printk(KERN_ERR "cpufreq-davinci: Unable to get ARM clock\n");
+ return PTR_ERR(armclk);
+ }
+
+ if (policy->cpu != 0) {
+ clk_put(armclk);
+ return -EINVAL;
+ }
+
+ policy->cur = policy->min = policy->max = davinci_getspeed(0);
+
+ davinci_soc_info.init_cpufreq_table(&freq_table);
+ if (freq_table) {
+ result = cpufreq_frequency_table_cpuinfo(policy, freq_table);
+ if (!result)
+ cpufreq_frequency_table_get_attr(freq_table,
+ policy->cpu);
+ } else {
+ policy->cpuinfo.min_freq = policy->min;
+ policy->cpuinfo.max_freq = policy->max;
+ }
+
+ clk_set_rate(armclk, policy->cpuinfo.max_freq * 1000);
+
+ policy->min = policy->cpuinfo.min_freq;
+ policy->max = policy->cpuinfo.max_freq;
+ policy->cur = davinci_getspeed(0);
+
+ /*
+ * Time measurement across the target() function yields
+ * ~500 us time taken with no drivers on notification list.
+ * Setting the latency to 700 us to accomodate addition of
+ * drivers to pre/post change notification list.
+ */
+ policy->cpuinfo.transition_latency = 700 * 1000;
+ return 0;
+}
+
+static int davinci_cpu_exit(struct cpufreq_policy *policy)
+{
+ clk_put(armclk);
+ return 0;
+}
+
+static struct freq_attr *davinci_cpufreq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver davinci_driver = {
+ .flags = CPUFREQ_STICKY,
+ .verify = davinci_verify_speed,
+ .target = davinci_target,
+ .get = davinci_getspeed,
+ .init = davinci_cpu_init,
+ .exit = davinci_cpu_exit,
+ .name = "davinci",
+ .attr = davinci_cpufreq_attr,
+};
+
+static int __init davinci_cpufreq_init(void)
+{
+ return cpufreq_register_driver(&davinci_driver);
+}
+
+late_initcall(davinci_cpufreq_init);
+
+/*
+ * if ever we want to remove this, upon cleanup call:
+ *
+ * cpufreq_unregister_driver()
+ * cpufreq_frequency_table_put_attr()
+ */
+
@@ -12,6 +12,8 @@
#ifndef __ARCH_ARM_MACH_DAVINCI_COMMON_H
#define __ARCH_ARM_MACH_DAVINCI_COMMON_H
+#include <linux/cpufreq.h>
+
struct sys_timer;
extern struct sys_timer davinci_timer;
@@ -68,6 +70,7 @@ struct davinci_soc_info {
struct emac_platform_data *emac_pdata;
dma_addr_t sram_dma;
unsigned sram_len;
+ void (*init_cpufreq_table) (struct cpufreq_frequency_table **);
};
extern struct davinci_soc_info davinci_soc_info;
Adds a basic CPUFreq driver for DaVinci devices registering with the kernel CPUFreq infrastructure. Signed-off-by: Sekhar Nori <nsekhar@ti.com> --- arch/arm/Kconfig | 2 +- arch/arm/mach-davinci/Makefile | 3 + arch/arm/mach-davinci/cpufreq.c | 183 +++++++++++++++++++++++++++ arch/arm/mach-davinci/include/mach/common.h | 3 + 4 files changed, 190 insertions(+), 1 deletions(-) create mode 100644 arch/arm/mach-davinci/cpufreq.c