cpufreq: OMAP: cleanup for multi-SoC support, move into drivers/cpufreq
Move OMAP cpufreq driver from arch/arm/mach-omap2 into
drivers/cpufreq, along with a few cleanups:
- generalize support for better handling of different SoCs in the OMAP
- use OPP layer instead of OMAP clock internals for frequency table init
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[khilman@ti.com: move to drivers]
Signed-off-by: Kevin Hilman <khilman@ti.com>
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c
new file mode 100644
index 0000000..a6b2be7
--- /dev/null
+++ b/drivers/cpufreq/omap-cpufreq.c
@@ -0,0 +1,188 @@
+/*
+ * 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) 2007-2011 Texas Instruments, Inc.
+ * - OMAP3/4 support by Rajendra Nayak, Santosh Shilimkar
+ *
+ * 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);
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ return ret;
+}
+
+static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy)
+{
+ int result = 0;
+ struct device *mpu_dev;
+
+ if (cpu_is_omap24xx())
+ mpu_clk = clk_get(NULL, "virt_prcm_set");
+ else if (cpu_is_omap34xx())
+ mpu_clk = clk_get(NULL, "dpll1_ck");
+ else if (cpu_is_omap44xx())
+ mpu_clk = clk_get(NULL, "dpll_mpu_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 = "omap",
+ .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 OMAP SoCs");
+MODULE_LICENSE("GPL");
+module_init(omap_cpufreq_init);
+module_exit(omap_cpufreq_exit);