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authorSantosh Shilimkar <santosh.shilimkar@ti.com>2011-02-28 17:34:23 +0530
committerNicolas Pitre <nicolas.pitre@linaro.org>2011-04-01 23:03:01 -0400
commite5ce464e0053a9fe61eadf0d9f2cf3cadb4a2425 (patch)
treefa8b2613e36f2dd811bfc0048dba3c6db42701c8 /arch/arm/mach-omap2
parent4e050197c77120a3009066ce74494a77873440cf (diff)
omap: cpufreq: Split omap1 and omap2plus cpufreq drivers.
This patch is an attempt to cleanup the #ifdeferry in the omap cpufreq drivers. The split betwenn omap1 and omap2plus is logical because - omap1 doesn't support opp layer. - omap1 build is seperate from omap2plus. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Vishwanath BS <vishwanath.bs@ti.com>
Diffstat (limited to 'arch/arm/mach-omap2')
-rw-r--r--arch/arm/mach-omap2/Makefile3
-rw-r--r--arch/arm/mach-omap2/omap2plus-cpufreq.c197
2 files changed, 200 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
index d96bf8f7021..394190aef27 100644
--- a/arch/arm/mach-omap2/Makefile
+++ b/arch/arm/mach-omap2/Makefile
@@ -56,6 +56,9 @@ obj-$(CONFIG_ARCH_OMAP3) += opp3xxx_data.o
obj-$(CONFIG_ARCH_OMAP4) += opp4xxx_data.o
endif
+# CPUFREQ driver
+obj-$(CONFIG_CPU_FREQ) += omap2plus-cpufreq.o
+
# Power Management
ifeq ($(CONFIG_PM),y)
obj-$(CONFIG_ARCH_OMAP2) += pm24xx.o
diff --git a/arch/arm/mach-omap2/omap2plus-cpufreq.c b/arch/arm/mach-omap2/omap2plus-cpufreq.c
new file mode 100644
index 00000000000..48da8672443
--- /dev/null
+++ b/arch/arm/mach-omap2/omap2plus-cpufreq.c
@@ -0,0 +1,197 @@
+/*
+ * OMAP2PLUS cpufreq driver
+ *
+ * CPU frequency scaling for OMAP
+ *
+ * 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 <linux/opp.h>
+
+#include <asm/system.h>
+#include <asm/smp_plat.h>
+
+#include <plat/clock.h>
+#include <plat/omap-pm.h>
+#include <plat/common.h>
+
+#include <mach/hardware.h>
+
+#define VERY_HI_RATE 900000000
+
+static struct cpufreq_frequency_table *freq_table;
+static struct clk *mpu_clk;
+
+static int omap_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(mpu_clk, policy->min * 1000) / 1000;
+ policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000;
+ cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+ policy->cpuinfo.max_freq);
+ return 0;
+}
+
+static unsigned int omap_getspeed(unsigned int cpu)
+{
+ unsigned long rate;
+
+ if (cpu)
+ return 0;
+
+ rate = clk_get_rate(mpu_clk) / 1000;
+ return rate;
+}
+
+static int omap_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ int ret = 0;
+ struct cpufreq_freqs freqs;
+
+ /* Ensure desired rate is within allowed range. Some govenors
+ * (ondemand) will just pass target_freq=0 to get the minimum. */
+ if (target_freq < policy->min)
+ target_freq = policy->min;
+ if (target_freq > policy->max)
+ target_freq = policy->max;
+
+ freqs.old = omap_getspeed(0);
+ freqs.new = clk_round_rate(mpu_clk, 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
+ pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new);
+#endif
+
+ ret = clk_set_rate(mpu_clk, freqs.new * 1000);
+ if (ret)
+ return ret;
+
+ /*
+ * Generic CPUFREQ driver jiffy update is under !SMP. So jiffies
+ * won't get updated when UP machine cpufreq build with
+ * CONFIG_SMP enabled. Below code is added only to manage that
+ * scenario
+ */
+ if (!is_smp())
+ loops_per_jiffy =
+ cpufreq_scale(loops_per_jiffy, freqs.old, freqs.new);
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ return ret;
+}
+
+static int __init omap_cpu_init(struct cpufreq_policy *policy)
+{
+ int result = 0;
+ struct device *mpu_dev;
+
+ mpu_clk = clk_get(NULL, "cpu_ck");
+ if (IS_ERR(mpu_clk))
+ return PTR_ERR(mpu_clk);
+
+ if (policy->cpu != 0)
+ return -EINVAL;
+
+ policy->cur = policy->min = policy->max = omap_getspeed(0);
+
+ mpu_dev = omap2_get_mpuss_device();
+ if (!mpu_dev) {
+ pr_warning("%s: unable to get the mpu device\n", __func__);
+ return -EINVAL;
+ }
+ opp_init_cpufreq_table(mpu_dev, &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 = clk_round_rate(mpu_clk, 0) / 1000;
+ policy->cpuinfo.max_freq = clk_round_rate(mpu_clk,
+ VERY_HI_RATE) / 1000;
+ }
+
+ policy->min = policy->cpuinfo.min_freq;
+ policy->max = policy->cpuinfo.max_freq;
+ policy->cur = omap_getspeed(0);
+
+ /* FIXME: what's the actual transition time? */
+ policy->cpuinfo.transition_latency = 300 * 1000;
+
+ return 0;
+}
+
+static int omap_cpu_exit(struct cpufreq_policy *policy)
+{
+ clk_exit_cpufreq_table(&freq_table);
+ clk_put(mpu_clk);
+ return 0;
+}
+
+static struct freq_attr *omap_cpufreq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver omap_driver = {
+ .flags = CPUFREQ_STICKY,
+ .verify = omap_verify_speed,
+ .target = omap_target,
+ .get = omap_getspeed,
+ .init = omap_cpu_init,
+ .exit = omap_cpu_exit,
+ .name = "omap2plus",
+ .attr = omap_cpufreq_attr,
+};
+
+static int __init omap_cpufreq_init(void)
+{
+ return cpufreq_register_driver(&omap_driver);
+}
+
+static void __exit omap_cpufreq_exit(void)
+{
+ cpufreq_unregister_driver(&omap_driver);
+}
+
+MODULE_DESCRIPTION("cpufreq driver for OMAP2PLUS SOCs");
+MODULE_LICENSE("GPL");
+module_init(omap_cpufreq_init);
+module_exit(omap_cpufreq_exit);