Initial import

1 files changed, 239 insertions, 0 deletions

diff --git a/drivers/cpufreq/integrator-cpufreq.c b/drivers/cpufreq/integrator-cpufreq.c
new file mode 100644
index 000000000..129e266f7
--- /dev/null
+++ b/drivers/cpufreq/integrator-cpufreq.c
@@ -0,0 +1,239 @@
+/*
+ *  Copyright (C) 2001-2002 Deep Blue Solutions Ltd.
+ *
+ * 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.
+ *
+ * CPU support functions
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/cpufreq.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/mach-types.h>
+#include <asm/hardware/icst.h>
+
+static void __iomem *cm_base;
+/* The cpufreq driver only use the OSC register */
+#define INTEGRATOR_HDR_OSC_OFFSET       0x08
+#define INTEGRATOR_HDR_LOCK_OFFSET      0x14
+
+static struct cpufreq_driver integrator_driver;
+
+static const struct icst_params lclk_params = {
+	.ref		= 24000000,
+	.vco_max	= ICST525_VCO_MAX_5V,
+	.vco_min	= ICST525_VCO_MIN,
+	.vd_min		= 8,
+	.vd_max		= 132,
+	.rd_min		= 24,
+	.rd_max		= 24,
+	.s2div		= icst525_s2div,
+	.idx2s		= icst525_idx2s,
+};
+
+static const struct icst_params cclk_params = {
+	.ref		= 24000000,
+	.vco_max	= ICST525_VCO_MAX_5V,
+	.vco_min	= ICST525_VCO_MIN,
+	.vd_min		= 12,
+	.vd_max		= 160,
+	.rd_min		= 24,
+	.rd_max		= 24,
+	.s2div		= icst525_s2div,
+	.idx2s		= icst525_idx2s,
+};
+
+/*
+ * Validate the speed policy.
+ */
+static int integrator_verify_policy(struct cpufreq_policy *policy)
+{
+	struct icst_vco vco;
+
+	cpufreq_verify_within_cpu_limits(policy);
+
+	vco = icst_hz_to_vco(&cclk_params, policy->max * 1000);
+	policy->max = icst_hz(&cclk_params, vco) / 1000;
+
+	vco = icst_hz_to_vco(&cclk_params, policy->min * 1000);
+	policy->min = icst_hz(&cclk_params, vco) / 1000;
+
+	cpufreq_verify_within_cpu_limits(policy);
+	return 0;
+}
+
+
+static int integrator_set_target(struct cpufreq_policy *policy,
+				 unsigned int target_freq,
+				 unsigned int relation)
+{
+	cpumask_t cpus_allowed;
+	int cpu = policy->cpu;
+	struct icst_vco vco;
+	struct cpufreq_freqs freqs;
+	u_int cm_osc;
+
+	/*
+	 * Save this threads cpus_allowed mask.
+	 */
+	cpus_allowed = current->cpus_allowed;
+
+	/*
+	 * Bind to the specified CPU.  When this call returns,
+	 * we should be running on the right CPU.
+	 */
+	set_cpus_allowed_ptr(current, cpumask_of(cpu));
+	BUG_ON(cpu != smp_processor_id());
+
+	/* get current setting */
+	cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
+
+	if (machine_is_integrator()) {
+		vco.s = (cm_osc >> 8) & 7;
+	} else if (machine_is_cintegrator()) {
+		vco.s = 1;
+	}
+	vco.v = cm_osc & 255;
+	vco.r = 22;
+	freqs.old = icst_hz(&cclk_params, vco) / 1000;
+
+	/* icst_hz_to_vco rounds down -- so we need the next
+	 * larger freq in case of CPUFREQ_RELATION_L.
+	 */
+	if (relation == CPUFREQ_RELATION_L)
+		target_freq += 999;
+	if (target_freq > policy->max)
+		target_freq = policy->max;
+	vco = icst_hz_to_vco(&cclk_params, target_freq * 1000);
+	freqs.new = icst_hz(&cclk_params, vco) / 1000;
+
+	if (freqs.old == freqs.new) {
+		set_cpus_allowed_ptr(current, &cpus_allowed);
+		return 0;
+	}
+
+	cpufreq_freq_transition_begin(policy, &freqs);
+
+	cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
+
+	if (machine_is_integrator()) {
+		cm_osc &= 0xfffff800;
+		cm_osc |= vco.s << 8;
+	} else if (machine_is_cintegrator()) {
+		cm_osc &= 0xffffff00;
+	}
+	cm_osc |= vco.v;
+
+	__raw_writel(0xa05f, cm_base + INTEGRATOR_HDR_LOCK_OFFSET);
+	__raw_writel(cm_osc, cm_base + INTEGRATOR_HDR_OSC_OFFSET);
+	__raw_writel(0, cm_base + INTEGRATOR_HDR_LOCK_OFFSET);
+
+	/*
+	 * Restore the CPUs allowed mask.
+	 */
+	set_cpus_allowed_ptr(current, &cpus_allowed);
+
+	cpufreq_freq_transition_end(policy, &freqs, 0);
+
+	return 0;
+}
+
+static unsigned int integrator_get(unsigned int cpu)
+{
+	cpumask_t cpus_allowed;
+	unsigned int current_freq;
+	u_int cm_osc;
+	struct icst_vco vco;
+
+	cpus_allowed = current->cpus_allowed;
+
+	set_cpus_allowed_ptr(current, cpumask_of(cpu));
+	BUG_ON(cpu != smp_processor_id());
+
+	/* detect memory etc. */
+	cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
+
+	if (machine_is_integrator()) {
+		vco.s = (cm_osc >> 8) & 7;
+	} else {
+		vco.s = 1;
+	}
+	vco.v = cm_osc & 255;
+	vco.r = 22;
+
+	current_freq = icst_hz(&cclk_params, vco) / 1000; /* current freq */
+
+	set_cpus_allowed_ptr(current, &cpus_allowed);
+
+	return current_freq;
+}
+
+static int integrator_cpufreq_init(struct cpufreq_policy *policy)
+{
+
+	/* set default policy and cpuinfo */
+	policy->max = policy->cpuinfo.max_freq = 160000;
+	policy->min = policy->cpuinfo.min_freq = 12000;
+	policy->cpuinfo.transition_latency = 1000000; /* 1 ms, assumed */
+
+	return 0;
+}
+
+static struct cpufreq_driver integrator_driver = {
+	.flags		= CPUFREQ_NEED_INITIAL_FREQ_CHECK,
+	.verify		= integrator_verify_policy,
+	.target		= integrator_set_target,
+	.get		= integrator_get,
+	.init		= integrator_cpufreq_init,
+	.name		= "integrator",
+};
+
+static int __init integrator_cpufreq_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res)
+		return -ENODEV;
+
+	cm_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!cm_base)
+		return -ENODEV;
+
+	return cpufreq_register_driver(&integrator_driver);
+}
+
+static int __exit integrator_cpufreq_remove(struct platform_device *pdev)
+{
+	return cpufreq_unregister_driver(&integrator_driver);
+}
+
+static const struct of_device_id integrator_cpufreq_match[] = {
+	{ .compatible = "arm,core-module-integrator"},
+	{ },
+};
+
+static struct platform_driver integrator_cpufreq_driver = {
+	.driver = {
+		.name = "integrator-cpufreq",
+		.of_match_table = integrator_cpufreq_match,
+	},
+	.remove = __exit_p(integrator_cpufreq_remove),
+};
+
+module_platform_driver_probe(integrator_cpufreq_driver,
+			     integrator_cpufreq_probe);
+
+MODULE_AUTHOR ("Russell M. King");
+MODULE_DESCRIPTION ("cpufreq driver for ARM Integrator CPUs");
+MODULE_LICENSE ("GPL");