Merge branch 'clkfwk'

3 files changed, 111 insertions, 134 deletions

diff --git a/arch/sh/kernel/cpu/clock.c b/arch/sh/kernel/cpu/clock.c
index 63251549e9a..92807ffa8e2 100644
--- a/arch/sh/kernel/cpu/clock.c
+++ b/arch/sh/kernel/cpu/clock.c
@@ -229,6 +229,22 @@ void clk_recalc_rate(struct clk *clk)
 }
 EXPORT_SYMBOL_GPL(clk_recalc_rate);
 
+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 clk_get_rate(clk);
+}
+EXPORT_SYMBOL_GPL(clk_round_rate);
+
 /*
  * Returns a clock. Note that we first try to use device id on the bus
  * and clock name. If this fails, we try to use clock name only.
diff --git a/arch/sh/kernel/cpu/sh4a/clock-sh7722.c b/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
index 51b386d454d..a0fd8bb21f7 100644
--- a/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
+++ b/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
@@ -387,9 +387,24 @@ out_err:
 	return err;
 }
 
+static long sh7722_frqcr_round_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long parent_rate = clk->parent->rate;
+	int div;
+
+	/* look for multiplier/divisor pair */
+	div = sh7722_find_divisors(parent_rate, rate);
+	if (div < 0)
+		return clk->rate;
+
+	/* calculate new value of clock rate */
+	return parent_rate * 2 / div;
+}
+
 static struct clk_ops sh7722_frqcr_clk_ops = {
 	.recalc = sh7722_frqcr_recalc,
 	.set_rate = sh7722_frqcr_set_rate,
+	.round_rate = sh7722_frqcr_round_rate,
 };
 
 /*
diff --git a/arch/sh/kernel/cpufreq.c b/arch/sh/kernel/cpufreq.c
index 47abf6e49df..675118d6aea 100644
--- a/arch/sh/kernel/cpufreq.c
+++ b/arch/sh/kernel/cpufreq.c
@@ -3,89 +3,51 @@
  *
  * cpufreq driver for the SuperH processors.
  *
- * Copyright (C) 2002, 2003, 2004, 2005 Paul Mundt
+ * Copyright (C) 2002 - 2007 Paul Mundt
  * Copyright (C) 2002 M. R. Brown
  *
- * 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.
+ * Clock framework bits from arch/avr32/mach-at32ap/cpufreq.c
+ *
+ *   Copyright (C) 2004-2007 Atmel Corporation
+ *
+ * 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/types.h>
 #include <linux/cpufreq.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/slab.h>
 #include <linux/init.h>
-#include <linux/delay.h>
+#include <linux/err.h>
 #include <linux/cpumask.h>
 #include <linux/smp.h>
 #include <linux/sched.h>	/* set_cpus_allowed() */
-
+#include <linux/io.h>
+#include <linux/clk.h>
 #include <asm/processor.h>
 #include <asm/watchdog.h>
 #include <asm/freq.h>
-#include <asm/io.h>
-
-/*
- * For SuperH, each policy change requires that we change the IFC, BFC, and
- * PFC at the same time.  Here we define sane values that won't trash the
- * system.
- *
- * Note the max set is computed at runtime, we use the divisors that we booted
- * with to setup our maximum operating frequencies.
- */
-struct clock_set {
-	unsigned int ifc;
-	unsigned int bfc;
-	unsigned int pfc;
-} clock_sets[] = {
-#if defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH2)
-	{ 0, 0, 0 },	/* not implemented yet */
-#elif defined(CONFIG_CPU_SH4)
-	{ 4, 8, 8 },	/* min - IFC: 1/4, BFC: 1/8, PFC: 1/8 */
-	{ 1, 2, 2 },	/* max - IFC: 1, BFC: 1/2, PFC: 1/2 */
-#endif
-};
-
-#define MIN_CLOCK_SET	0
-#define MAX_CLOCK_SET	(ARRAY_SIZE(clock_sets) - 1)
-
-/*
- * For the time being, we only support two frequencies, which in turn are
- * aimed at the POWERSAVE and PERFORMANCE policies, which in turn are derived
- * directly from the respective min/max clock sets. Technically we could
- * support a wider range of frequencies, but these vary far too much for each
- * CPU subtype (and we'd have to construct a frequency table for each subtype).
- *
- * Maybe something to implement in the future..
- */
-#define SH_FREQ_MAX	0
-#define SH_FREQ_MIN	1
+#include <asm/clock.h>
 
-static struct cpufreq_frequency_table sh_freqs[] = {
-	{ SH_FREQ_MAX,	0 },
-	{ SH_FREQ_MIN,	0 },
-	{ 0,		CPUFREQ_TABLE_END },
-};
+static struct clk *cpuclk;
 
-static void sh_cpufreq_update_clocks(unsigned int set)
+static unsigned int sh_cpufreq_get(unsigned int cpu)
 {
-	current_cpu_data.cpu_clock = current_cpu_data.master_clock / clock_sets[set].ifc;
-	current_cpu_data.bus_clock = current_cpu_data.master_clock / clock_sets[set].bfc;
-	current_cpu_data.module_clock = current_cpu_data.master_clock / clock_sets[set].pfc;
-	current_cpu_data.loops_per_jiffy = loops_per_jiffy;
+	return (clk_get_rate(cpuclk) + 500) / 1000;
 }
 
-/* XXX: This needs to be split out per CPU and CPU subtype. */
 /*
  * Here we notify other drivers of the proposed change and the final change.
  */
-static int sh_cpufreq_setstate(unsigned int cpu, unsigned int set)
+static int sh_cpufreq_target(struct cpufreq_policy *policy,
+			     unsigned int target_freq,
+			     unsigned int relation)
 {
-	unsigned short frqcr = ctrl_inw(FRQCR);
+	unsigned int cpu = policy->cpu;
 	cpumask_t cpus_allowed;
 	struct cpufreq_freqs freqs;
+	long freq;
 
 	if (!cpu_online(cpu))
 		return -ENODEV;
@@ -95,125 +57,109 @@ static int sh_cpufreq_setstate(unsigned int cpu, unsigned int set)
 
 	BUG_ON(smp_processor_id() != cpu);
 
-	freqs.cpu = cpu;
-	freqs.old = current_cpu_data.cpu_clock / 1000;
-	freqs.new = (current_cpu_data.master_clock / clock_sets[set].ifc) / 1000;
+	/* Convert target_freq from kHz to Hz */
+	freq = clk_round_rate(cpuclk, target_freq * 1000);
 
-	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
-#if defined(CONFIG_CPU_SH3)
-	frqcr |= (newstate & 0x4000) << 14;
-	frqcr |= (newstate & 0x000c) <<  2;
-#elif defined(CONFIG_CPU_SH4)
-	/*
-	 * FRQCR.PLL2EN is 1, we need to allow the PLL to stabilize by
-	 * initializing the WDT.
-	 */
-	if (frqcr & (1 << 9)) {
-		__u8 csr;
-
-		/*
-		 * Set the overflow period to the highest available,
-		 * in this case a 1/4096 division ratio yields a 5.25ms
-		 * overflow period. See asm-sh/watchdog.h for more
-		 * information and a range of other divisors.
-		 */
-		csr = sh_wdt_read_csr();
-		csr |= WTCSR_CKS_4096;
-		sh_wdt_write_csr(csr);
-
-		sh_wdt_write_cnt(0);
-	}
-	frqcr &= 0x0e00;	/* Clear ifc, bfc, pfc */
-	frqcr |= get_ifc_value(clock_sets[set].ifc) << 6;
-	frqcr |= get_bfc_value(clock_sets[set].bfc) << 3;
-	frqcr |= get_pfc_value(clock_sets[set].pfc);
-#endif
-	ctrl_outw(frqcr, FRQCR);
-	sh_cpufreq_update_clocks(set);
+	if (freq < (policy->min * 1000) || freq > (policy->max * 1000))
+		return -EINVAL;
+
+	pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000);
 
+	freqs.cpu	= cpu;
+	freqs.old	= sh_cpufreq_get(cpu);
+	freqs.new	= (freq + 500) / 1000;
+	freqs.flags	= 0;
+
+	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 	set_cpus_allowed(current, cpus_allowed);
+	clk_set_rate(cpuclk, freq);
 	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 
+	pr_debug("cpufreq: set frequency %lu Hz\n", freq);
+
 	return 0;
 }
 
 static int sh_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
-	unsigned int min_freq, max_freq;
-	unsigned int ifc, bfc, pfc;
+	printk(KERN_INFO "cpufreq: SuperH CPU frequency driver.\n");
 
 	if (!cpu_online(policy->cpu))
 		return -ENODEV;
 
-	/* Update our maximum clock set */
-	get_current_frequency_divisors(&ifc, &bfc, &pfc);
-	clock_sets[MAX_CLOCK_SET].ifc = ifc;
-	clock_sets[MAX_CLOCK_SET].bfc = bfc;
-	clock_sets[MAX_CLOCK_SET].pfc = pfc;
-
-	/* Convert from Hz to kHz */
-	max_freq = current_cpu_data.cpu_clock / 1000;
-	min_freq = (current_cpu_data.master_clock / clock_sets[MIN_CLOCK_SET].ifc) / 1000;
-	
-	sh_freqs[SH_FREQ_MAX].frequency = max_freq;
-	sh_freqs[SH_FREQ_MIN].frequency = min_freq;
+	cpuclk = clk_get(NULL, "cpu_clk");
+	if (IS_ERR(cpuclk)) {
+		printk(KERN_ERR "cpufreq: couldn't get CPU clk\n");
+		return PTR_ERR(cpuclk);
+	}
 
 	/* cpuinfo and default policy values */
-	policy->governor                   = CPUFREQ_DEFAULT_GOVERNOR;
+	policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000;
+	policy->cpuinfo.max_freq = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000;
 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
-	policy->cur                        = max_freq;
 
-	return cpufreq_frequency_table_cpuinfo(policy, &sh_freqs[0]);
-}
+	policy->governor	= CPUFREQ_DEFAULT_GOVERNOR;
+	policy->cur		= sh_cpufreq_get(policy->cpu);
+	policy->min		= policy->cpuinfo.min_freq;
+	policy->max		= policy->cpuinfo.max_freq;
 
-static int sh_cpufreq_verify(struct cpufreq_policy *policy)
-{
-	return cpufreq_frequency_table_verify(policy, &sh_freqs[0]);
-}
 
-static int sh_cpufreq_target(struct cpufreq_policy *policy,
-			     unsigned int target_freq,
-			     unsigned int relation)
-{
-	unsigned int set, idx = 0;
+	/*
+	 * Catch the cases where the clock framework hasn't been wired up
+	 * properly to support scaling.
+	 */
+	if (unlikely(policy->min == policy->max)) {
+		printk(KERN_ERR "cpufreq: clock framework rate rounding "
+		       "not supported on this CPU.\n");
 
-	if (cpufreq_frequency_table_target(policy, &sh_freqs[0], target_freq, relation, &idx))
+		clk_put(cpuclk);
 		return -EINVAL;
+	}
 
-	set = (idx == SH_FREQ_MIN) ? MIN_CLOCK_SET : MAX_CLOCK_SET;
+	printk(KERN_INFO "cpufreq: Frequencies - Minimum %u.%03u MHz, "
+	       "Maximum %u.%03u MHz.\n",
+	       policy->min / 1000, policy->min % 1000,
+	       policy->max / 1000, policy->max % 1000);
 
-	sh_cpufreq_setstate(policy->cpu, set);
+	return 0;
+}
 
+static int sh_cpufreq_verify(struct cpufreq_policy *policy)
+{
+	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+				     policy->cpuinfo.max_freq);
+	return 0;
+}
+
+static int sh_cpufreq_exit(struct cpufreq_policy *policy)
+{
+	clk_put(cpuclk);
 	return 0;
 }
 
 static struct cpufreq_driver sh_cpufreq_driver = {
 	.owner		= THIS_MODULE,
-	.name		= "SH cpufreq",
+	.name		= "sh",
 	.init		= sh_cpufreq_cpu_init,
 	.verify		= sh_cpufreq_verify,
 	.target		= sh_cpufreq_target,
+	.get		= sh_cpufreq_get,
+	.exit		= sh_cpufreq_exit,
 };
 
-static int __init sh_cpufreq_init(void)
+static int __init sh_cpufreq_module_init(void)
 {
-	if (!current_cpu_data.cpu_clock)
-		return -EINVAL;
-	if (cpufreq_register_driver(&sh_cpufreq_driver))
-		return -EINVAL;
-
-	return 0;
+	return cpufreq_register_driver(&sh_cpufreq_driver);
 }
 
-static void __exit sh_cpufreq_exit(void)
+static void __exit sh_cpufreq_module_exit(void)
 {
 	cpufreq_unregister_driver(&sh_cpufreq_driver);
 }
 
-module_init(sh_cpufreq_init);
-module_exit(sh_cpufreq_exit);
+module_init(sh_cpufreq_module_init);
+module_exit(sh_cpufreq_module_exit);
 
 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
 MODULE_DESCRIPTION("cpufreq driver for SuperH");
 MODULE_LICENSE("GPL");
-