1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/cpufreq/dbx500-cpufreq.c b/drivers/cpufreq/dbx500-cpufreq.c
new file mode 100644
index 00000000000..38edd733b4c
--- /dev/null
+++ b/drivers/cpufreq/dbx500-cpufreq.c
@@ -0,0 +1,324 @@
+/*
+ * Copyright (C) STMicroelectronics 2009
+ * Copyright (C) ST-Ericsson SA 2010-2011
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Sundar Iyer
+ * Author: Martin Persson
+ * Author: Jonas Aaberg <jonas.aberg@stericsson.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/mfd/dbx500-prcmu.h>
+#include <mach/id.h>
+
+static struct cpufreq_frequency_table db8500_freq_table[] = {
+	[0] = {
+		.index = 0,
+		.frequency = 200000,
+	},
+	[1] = {
+		.index = 1,
+		.frequency = 400000,
+	},
+	[2] = {
+		.index = 2,
+		.frequency = 800000,
+	},
+	[3] = {
+		/* Used for MAX_OPP, if available */
+		.index = 3,
+		.frequency = CPUFREQ_TABLE_END,
+	},
+	[4] = {
+		.index = 4,
+		.frequency = CPUFREQ_TABLE_END,
+	},
+};
+
+static struct cpufreq_frequency_table db5500_freq_table[] = {
+	[0] = {
+		.index = 0,
+		.frequency = 200000,
+	},
+	[1] = {
+		.index = 1,
+		.frequency = 396500,
+	},
+	[2] = {
+		.index = 2,
+		.frequency = 793000,
+	},
+	[3] = {
+		.index = 3,
+		.frequency = CPUFREQ_TABLE_END,
+	},
+};
+
+static struct cpufreq_frequency_table *freq_table;
+static int freq_table_len;
+
+static enum arm_opp db8500_idx2opp[] = {
+	ARM_EXTCLK,
+	ARM_50_OPP,
+	ARM_100_OPP,
+	ARM_MAX_OPP
+};
+
+static enum arm_opp db5500_idx2opp[] = {
+	ARM_EXTCLK,
+	ARM_50_OPP,
+	ARM_100_OPP,
+};
+
+static enum arm_opp *idx2opp;
+
+static struct freq_attr *dbx500_cpufreq_attr[] = {
+	&cpufreq_freq_attr_scaling_available_freqs,
+	NULL,
+};
+
+static int dbx500_cpufreq_verify_speed(struct cpufreq_policy *policy)
+{
+	return cpufreq_frequency_table_verify(policy, freq_table);
+}
+
+static int dbx500_cpufreq_target(struct cpufreq_policy *policy,
+				unsigned int target_freq,
+				unsigned int relation)
+{
+	struct cpufreq_freqs freqs;
+	unsigned int idx;
+
+	/* scale the target frequency to one of the extremes supported */
+	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;
+
+	/* Lookup the next frequency */
+	if (cpufreq_frequency_table_target
+	    (policy, freq_table, target_freq, relation, &idx)) {
+		return -EINVAL;
+	}
+
+	freqs.old = policy->cur;
+	freqs.new = freq_table[idx].frequency;
+
+	if (freqs.old == freqs.new)
+		return 0;
+
+	/* pre-change notification */
+	for_each_cpu(freqs.cpu, policy->cpus)
+		cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+	/* request the PRCM unit for opp change */
+	if (prcmu_set_arm_opp(idx2opp[idx])) {
+		pr_err("ux500-cpufreq:  Failed to set OPP level\n");
+		return -EINVAL;
+	}
+
+	/* post change notification */
+	for_each_cpu(freqs.cpu, policy->cpus)
+		cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+	return 0;
+}
+
+static unsigned int dbx500_cpufreq_getspeed(unsigned int cpu)
+{
+	int i;
+	/* request the prcm to get the current ARM opp */
+	for (i = 0; prcmu_get_arm_opp() != idx2opp[i]; i++)
+		;
+	return freq_table[i].frequency;
+}
+
+static void __init dbx500_cpufreq_init_maxopp_freq(void)
+{
+	struct prcmu_fw_version *fw_version = prcmu_get_fw_version();
+
+	if ((fw_version == NULL) || !prcmu_has_arm_maxopp())
+		return;
+
+	switch (fw_version->project) {
+	case PRCMU_FW_PROJECT_U8500:
+	case PRCMU_FW_PROJECT_U9500:
+		freq_table[3].frequency = 1000000;
+		break;
+	case PRCMU_FW_PROJECT_U8500_C2:
+	case PRCMU_FW_PROJECT_U9500_C2:
+		freq_table[3].frequency = 1150000;
+		break;
+	default:
+		break;
+	}
+}
+
+static bool initialized;
+
+static void __init dbx500_cpufreq_early_init(void)
+{
+	if (cpu_is_u5500()) {
+		freq_table = db5500_freq_table;
+		idx2opp = db5500_idx2opp;
+		freq_table_len = ARRAY_SIZE(db5500_freq_table);
+	} else if (cpu_is_u8500()) {
+		freq_table = db8500_freq_table;
+		idx2opp = db8500_idx2opp;
+		dbx500_cpufreq_init_maxopp_freq();
+		freq_table_len = ARRAY_SIZE(db8500_freq_table);
+	} else {
+		ux500_unknown_soc();
+	}
+	initialized = true;
+}
+
+/*
+ * This is called from localtimer initialization, via the clk_get_rate() for
+ * the smp_twd clock.  This is way before cpufreq is initialized.
+ */
+unsigned long dbx500_cpufreq_getfreq(void)
+{
+	if (!initialized)
+		dbx500_cpufreq_early_init();
+
+	return dbx500_cpufreq_getspeed(0) * 1000;
+}
+
+int dbx500_cpufreq_percent2freq(int percent)
+{
+	int op;
+	int i;
+
+	switch (percent) {
+	case 0:
+		/* Fall through */
+	case 25:
+		op = ARM_EXTCLK;
+		break;
+	case 50:
+		op = ARM_50_OPP;
+		break;
+	case 100:
+		op = ARM_100_OPP;
+		break;
+	case 125:
+		if (cpu_is_u8500() && prcmu_has_arm_maxopp())
+			op = ARM_MAX_OPP;
+		else
+			op = ARM_100_OPP;
+		break;
+	default:
+		pr_err("cpufreq-dbx500: Incorrect arm target value (%d).\n",
+		       percent);;
+		return -EINVAL;
+		break;
+	}
+
+	for (i = 0; idx2opp[i] != op && i < freq_table_len; i++)
+		;
+
+	if (freq_table[i].frequency == CPUFREQ_TABLE_END) {
+		pr_err("cpufreq-dbx500: Matching frequency does not exist!\n");
+		return -EINVAL;
+	}
+
+	return freq_table[i].frequency;
+}
+
+int dbx500_cpufreq_get_limits(int cpu, int r,
+			      unsigned int *min, unsigned int *max)
+{
+	int freq;
+	int ret;
+	static int old_freq;
+	struct cpufreq_policy p;
+
+	freq = dbx500_cpufreq_percent2freq(r);
+
+	if (freq < 0)
+		return -EINVAL;
+
+	if (freq != old_freq)
+		pr_debug("cpufreq-dbx500: set min arm freq to %d\n",
+			 freq);
+
+	(*min) = freq;
+
+	ret = cpufreq_get_policy(&p, cpu);
+	if (ret) {
+		pr_err("cpufreq-dbx500: Failed to get policy.\n");
+		return -EINVAL;
+	}
+
+	(*max) = p.max;
+	return 0;
+}
+
+static int __cpuinit dbx500_cpufreq_init(struct cpufreq_policy *policy)
+{
+	int res;
+	int i;
+
+	/* get policy fields based on the table */
+	res = cpufreq_frequency_table_cpuinfo(policy, freq_table);
+	if (!res)
+		cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
+	else {
+		pr_err("dbx500-cpufreq : Failed to read policy table\n");
+		return res;
+	}
+
+	policy->min = policy->cpuinfo.min_freq;
+	policy->max = policy->cpuinfo.max_freq;
+	policy->cur = dbx500_cpufreq_getspeed(policy->cpu);
+
+	for (i = 0; freq_table[i].frequency != policy->cur; i++)
+		;
+
+	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+
+	/*
+	 * FIXME : Need to take time measurement across the target()
+	 *	   function with no/some/all drivers in the notification
+	 *	   list.
+	 */
+	policy->cpuinfo.transition_latency = 20 * 1000; /* in ns */
+
+	/* policy sharing between dual CPUs */
+	cpumask_copy(policy->cpus, &cpu_present_map);
+
+	policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
+
+	return 0;
+}
+
+static struct cpufreq_driver dbx500_cpufreq_driver = {
+	.flags  = CPUFREQ_STICKY,
+	.verify = dbx500_cpufreq_verify_speed,
+	.target = dbx500_cpufreq_target,
+	.get    = dbx500_cpufreq_getspeed,
+	.init   = dbx500_cpufreq_init,
+	.name   = "DBX500",
+	.attr   = dbx500_cpufreq_attr,
+};
+
+static int __init dbx500_cpufreq_register(void)
+{
+	int i;
+
+	if (!initialized)
+		dbx500_cpufreq_early_init();
+
+	pr_info("dbx500-cpufreq : Available frequencies:\n");
+
+	for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++)
+		pr_info("  %d Mhz\n", freq_table[i].frequency / 1000);
+
+	return cpufreq_register_driver(&dbx500_cpufreq_driver);
+}
+device_initcall(dbx500_cpufreq_register);