openwrtv4/target/linux/ipq806x/patches-4.0/145-cpufreq-Add-a-cpufreq-krait-based-on-cpufre.patch
John Crispin 8e49b4b902 ipq806x: add & enable cpufreq support
This change set enables frequency scaling on ipq806x, which speeds-up
the CPU and allows it to achieve its max frequency.

These patches are cherry-picked & backported from the following location:
*130-132: linux-next
*133-143: LKML - https://lkml.org/lkml/2015/3/21/15
*144: derived from other qcom similar dts
*145: derived from https://chromium.googlesource.com/chromiumos/third_party/kernel/+/chromeos-3.14/drivers/cpufreq/cpufreq-krait.c

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>

SVN-Revision: 45730
2015-05-23 15:28:02 +00:00

461 lines
12 KiB
Diff

From dd77db4143290689d3a5e1ec61627233d0711b66 Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Fri, 30 May 2014 16:36:11 -0700
Subject: [PATCH] FROMLIST: cpufreq: Add a cpufreq-krait based on cpufreq-cpu0
Krait processors have individual clocks for each CPU that can
scale independently from one another. cpufreq-cpu0 is fairly
close to this, but assumes that there is only one clock for all
CPUs. Add a driver to support the Krait configuration.
TODO: Merge into cpufreq-cpu0? Or make generic?
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/cpufreq/Kconfig | 13 +++
drivers/cpufreq/Makefile | 1 +
drivers/cpufreq/cpufreq-krait.c | 190 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 204 insertions(+)
create mode 100644 drivers/cpufreq/cpufreq-krait.c
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -198,6 +198,19 @@ config CPUFREQ_DT
If in doubt, say N.
+config GENERIC_CPUFREQ_KRAIT
+ tristate "Krait cpufreq driver"
+ depends on HAVE_CLK && OF
+ # if CPU_THERMAL is on and THERMAL=m, CPU0 cannot be =y:
+ depends on !CPU_THERMAL || THERMAL
+ select PM_OPP
+ help
+ This adds a generic cpufreq driver for CPU0 frequency management.
+ It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
+ systems which share clock and voltage across all CPUs.
+
+ If in doubt, say N.
+
if X86
source "drivers/cpufreq/Kconfig.x86"
endif
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_CPU_FREQ_GOV_CONSERVATIVE)
obj-$(CONFIG_CPU_FREQ_GOV_COMMON) += cpufreq_governor.o
obj-$(CONFIG_CPUFREQ_DT) += cpufreq-dt.o
+obj-$(CONFIG_GENERIC_CPUFREQ_KRAIT) += cpufreq-krait.o
##################################################################################
# x86 drivers.
--- /dev/null
+++ b/drivers/cpufreq/cpufreq-krait.c
@@ -0,0 +1,390 @@
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ *
+ * The OPP code in function krait_set_target() is reused from
+ * drivers/cpufreq/omap-cpufreq.c
+ *
+ * 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/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpu_cooling.h>
+#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+static unsigned int transition_latency;
+static unsigned int voltage_tolerance; /* in percentage */
+
+static struct device *cpu_dev;
+static DEFINE_PER_CPU(struct clk *, krait_cpu_clks);
+static DEFINE_PER_CPU(struct regulator *, krait_supply_core);
+static struct cpufreq_frequency_table *freq_table;
+static struct thermal_cooling_device *cdev;
+
+struct cache_points {
+ unsigned long cache_freq;
+ unsigned int cache_volt;
+ unsigned long cpu_freq;
+};
+
+static struct regulator *krait_l2_reg;
+static struct clk *krait_l2_clk;
+static struct cache_points *krait_l2_points;
+static int nr_krait_l2_points;
+
+static int krait_parse_cache_points(struct device *dev,
+ struct device_node *of_node)
+{
+ const struct property *prop;
+ const __be32 *val;
+ int nr, i;
+
+ prop = of_find_property(of_node, "cache-points-kHz", NULL);
+ if (!prop)
+ return -ENODEV;
+ if (!prop->value)
+ return -ENODATA;
+
+ /*
+ * Each OPP is a set of tuples consisting of frequency and
+ * cpu-frequency like <freq-kHz volt-uV freq-kHz>.
+ */
+ nr = prop->length / sizeof(u32);
+ if (nr % 3) {
+ dev_err(dev, "%s: Invalid cache points\n", __func__);
+ return -EINVAL;
+ }
+ nr /= 3;
+
+ krait_l2_points = devm_kcalloc(dev, nr, sizeof(*krait_l2_points),
+ GFP_KERNEL);
+ if (!krait_l2_points)
+ return -ENOMEM;
+ nr_krait_l2_points = nr;
+
+ for (i = 0, val = prop->value; i < nr; i++) {
+ unsigned long cache_freq = be32_to_cpup(val++) * 1000;
+ unsigned int cache_volt = be32_to_cpup(val++);
+ unsigned long cpu_freq = be32_to_cpup(val++) * 1000;
+
+ krait_l2_points[i].cache_freq = cache_freq;
+ krait_l2_points[i].cache_volt = cache_volt;
+ krait_l2_points[i].cpu_freq = cpu_freq;
+ }
+
+ return 0;
+}
+
+static int krait_set_target(struct cpufreq_policy *policy, unsigned int index)
+{
+ struct dev_pm_opp *opp;
+ unsigned long volt = 0, volt_old = 0, tol = 0;
+ unsigned long freq, max_cpu_freq = 0;
+ unsigned int old_freq, new_freq;
+ long freq_Hz, freq_exact;
+ int ret, i;
+ struct clk *cpu_clk;
+ struct regulator *core;
+ unsigned int cpu;
+
+ cpu_clk = per_cpu(krait_cpu_clks, policy->cpu);
+
+ freq_Hz = clk_round_rate(cpu_clk, freq_table[index].frequency * 1000);
+ if (freq_Hz <= 0)
+ freq_Hz = freq_table[index].frequency * 1000;
+
+ freq_exact = freq_Hz;
+ new_freq = freq_Hz / 1000;
+ old_freq = clk_get_rate(cpu_clk) / 1000;
+
+ core = per_cpu(krait_supply_core, policy->cpu);
+
+ rcu_read_lock();
+ opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_Hz);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ pr_err("failed to find OPP for %ld\n", freq_Hz);
+ return PTR_ERR(opp);
+ }
+ volt = dev_pm_opp_get_voltage(opp);
+ rcu_read_unlock();
+ tol = volt * voltage_tolerance / 100;
+ volt_old = regulator_get_voltage(core);
+
+ pr_debug("%u MHz, %ld mV --> %u MHz, %ld mV\n",
+ old_freq / 1000, volt_old ? volt_old / 1000 : -1,
+ new_freq / 1000, volt ? volt / 1000 : -1);
+
+ /* scaling up? scale voltage before frequency */
+ if (new_freq > old_freq) {
+ ret = regulator_set_voltage_tol(core, volt, tol);
+ if (ret) {
+ pr_err("failed to scale voltage up: %d\n", ret);
+ return ret;
+ }
+ }
+
+ ret = clk_set_rate(cpu_clk, freq_exact);
+ if (ret) {
+ pr_err("failed to set clock rate: %d\n", ret);
+ return ret;
+ }
+
+ /* scaling down? scale voltage after frequency */
+ if (new_freq < old_freq) {
+ ret = regulator_set_voltage_tol(core, volt, tol);
+ if (ret) {
+ pr_err("failed to scale voltage down: %d\n", ret);
+ clk_set_rate(cpu_clk, old_freq * 1000);
+ }
+ }
+
+ for_each_possible_cpu(cpu) {
+ freq = clk_get_rate(per_cpu(krait_cpu_clks, cpu));
+ max_cpu_freq = max(max_cpu_freq, freq);
+ }
+
+ for (i = 0; i < nr_krait_l2_points; i++) {
+ if (max_cpu_freq >= krait_l2_points[i].cpu_freq) {
+ if (krait_l2_reg) {
+ ret = regulator_set_voltage_tol(krait_l2_reg,
+ krait_l2_points[i].cache_volt,
+ tol);
+ if (ret) {
+ pr_err("failed to scale l2 voltage: %d\n",
+ ret);
+ }
+ }
+ ret = clk_set_rate(krait_l2_clk,
+ krait_l2_points[i].cache_freq);
+ if (ret)
+ pr_err("failed to scale l2 clk: %d\n", ret);
+ break;
+ }
+
+ }
+
+ return ret;
+}
+
+static int krait_cpufreq_init(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ policy->clk = per_cpu(krait_cpu_clks, policy->cpu);
+
+ ret = cpufreq_table_validate_and_show(policy, freq_table);
+ if (ret) {
+ pr_err("%s: invalid frequency table: %d\n", __func__, ret);
+ return ret;
+ }
+
+ policy->cpuinfo.transition_latency = transition_latency;
+
+ return 0;
+}
+
+static struct cpufreq_driver krait_cpufreq_driver = {
+ .flags = CPUFREQ_STICKY,
+ .verify = cpufreq_generic_frequency_table_verify,
+ .target_index = krait_set_target,
+ .get = cpufreq_generic_get,
+ .init = krait_cpufreq_init,
+ .name = "generic_krait",
+ .attr = cpufreq_generic_attr,
+};
+
+static int krait_cpufreq_probe(struct platform_device *pdev)
+{
+ struct device_node *np, *cache;
+ int ret, i;
+ unsigned int cpu;
+ struct device *dev;
+ struct clk *clk;
+ struct regulator *core;
+ unsigned long freq_Hz, freq, max_cpu_freq;
+ struct dev_pm_opp *opp;
+ unsigned long volt, tol;
+
+ cpu_dev = get_cpu_device(0);
+ if (!cpu_dev) {
+ pr_err("failed to get krait device\n");
+ return -ENODEV;
+ }
+
+ np = of_node_get(cpu_dev->of_node);
+ if (!np) {
+ pr_err("failed to find krait node\n");
+ return -ENOENT;
+ }
+
+ ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
+ if (ret) {
+ pr_err("failed to init cpufreq table: %d\n", ret);
+ goto out_put_node;
+ }
+
+ of_property_read_u32(np, "voltage-tolerance", &voltage_tolerance);
+
+ if (of_property_read_u32(np, "clock-latency", &transition_latency))
+ transition_latency = CPUFREQ_ETERNAL;
+
+ cache = of_find_next_cache_node(np);
+ if (cache) {
+ struct device_node *vdd;
+
+ vdd = of_parse_phandle(cache, "vdd_dig-supply", 0);
+ if (vdd) {
+ krait_l2_reg = regulator_get(NULL, vdd->name);
+ if (IS_ERR(krait_l2_reg)) {
+ pr_warn("failed to get l2 vdd_dig supply\n");
+ krait_l2_reg = NULL;
+ }
+ of_node_put(vdd);
+ }
+
+ krait_l2_clk = of_clk_get(cache, 0);
+ if (!IS_ERR(krait_l2_clk)) {
+ ret = krait_parse_cache_points(&pdev->dev, cache);
+ if (ret)
+ clk_put(krait_l2_clk);
+ }
+ if (IS_ERR(krait_l2_clk) || ret)
+ krait_l2_clk = NULL;
+ }
+
+ for_each_possible_cpu(cpu) {
+ dev = get_cpu_device(cpu);
+ if (!dev) {
+ pr_err("failed to get krait device\n");
+ ret = -ENOENT;
+ goto out_free_table;
+ }
+ per_cpu(krait_cpu_clks, cpu) = clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ goto out_free_table;
+ }
+ core = devm_regulator_get(dev, "core");
+ if (IS_ERR(core)) {
+ pr_debug("failed to get core regulator\n");
+ ret = PTR_ERR(core);
+ goto out_free_table;
+ }
+ per_cpu(krait_supply_core, cpu) = core;
+
+ freq_Hz = clk_get_rate(clk);
+
+ rcu_read_lock();
+ opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_Hz);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ pr_err("failed to find OPP for %ld\n", freq_Hz);
+ ret = PTR_ERR(opp);
+ goto out_free_table;
+ }
+ volt = dev_pm_opp_get_voltage(opp);
+ rcu_read_unlock();
+
+ tol = volt * voltage_tolerance / 100;
+ ret = regulator_set_voltage_tol(core, volt, tol);
+ if (ret) {
+ pr_err("failed to scale voltage up: %d\n", ret);
+ goto out_free_table;
+ }
+ ret = regulator_enable(core);
+ if (ret) {
+ pr_err("failed to enable regulator: %d\n", ret);
+ goto out_free_table;
+ }
+ max_cpu_freq = max(max_cpu_freq, freq);
+ }
+
+ for (i = 0; i < nr_krait_l2_points; i++) {
+ if (max_cpu_freq >= krait_l2_points[i].cpu_freq) {
+ if (krait_l2_reg) {
+ ret = regulator_set_voltage_tol(krait_l2_reg,
+ krait_l2_points[i].cache_volt,
+ tol);
+ if (ret)
+ pr_err("failed to scale l2 voltage: %d\n",
+ ret);
+ ret = regulator_enable(krait_l2_reg);
+ if (ret)
+ pr_err("failed to enable l2 voltage: %d\n",
+ ret);
+ }
+ break;
+ }
+
+ }
+
+ ret = cpufreq_register_driver(&krait_cpufreq_driver);
+ if (ret) {
+ pr_err("failed register driver: %d\n", ret);
+ goto out_free_table;
+ }
+ of_node_put(np);
+
+ /*
+ * For now, just loading the cooling device;
+ * thermal DT code takes care of matching them.
+ */
+ for_each_possible_cpu(cpu) {
+ dev = get_cpu_device(cpu);
+ np = of_node_get(dev->of_node);
+ if (of_find_property(np, "#cooling-cells", NULL)) {
+ cdev = of_cpufreq_cooling_register(np, cpumask_of(cpu));
+ if (IS_ERR(cdev))
+ pr_err("running cpufreq without cooling device: %ld\n",
+ PTR_ERR(cdev));
+ }
+ of_node_put(np);
+ }
+
+ return 0;
+
+out_free_table:
+ regulator_put(krait_l2_reg);
+ clk_put(krait_l2_clk);
+ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+out_put_node:
+ of_node_put(np);
+ return ret;
+}
+
+static int krait_cpufreq_remove(struct platform_device *pdev)
+{
+ cpufreq_cooling_unregister(cdev);
+ cpufreq_unregister_driver(&krait_cpufreq_driver);
+ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+ clk_put(krait_l2_clk);
+ regulator_put(krait_l2_reg);
+
+ return 0;
+}
+
+static struct platform_driver krait_cpufreq_platdrv = {
+ .driver = {
+ .name = "cpufreq-krait",
+ .owner = THIS_MODULE,
+ },
+ .probe = krait_cpufreq_probe,
+ .remove = krait_cpufreq_remove,
+};
+module_platform_driver(krait_cpufreq_platdrv);
+
+MODULE_DESCRIPTION("Krait CPUfreq driver");
+MODULE_LICENSE("GPL v2");
--- a/drivers/cpufreq/qcom-cpufreq.c
+++ b/drivers/cpufreq/qcom-cpufreq.c
@@ -168,11 +168,8 @@ static int __init qcom_cpufreq_populate_
static int __init qcom_cpufreq_driver_init(void)
{
- struct cpufreq_dt_platform_data pdata = { .independent_clocks = true };
struct platform_device_info devinfo = {
- .name = "cpufreq-dt",
- .data = &pdata,
- .size_data = sizeof(pdata),
+ .name = "cpufreq-krait",
};
struct device *cpu_dev;
struct device_node *np;