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-rw-r--r--target/linux/mediatek/patches/0033-cpufreq-mediatek-Add-MT8173-cpufreq-driver.patch604
1 files changed, 604 insertions, 0 deletions
diff --git a/target/linux/mediatek/patches/0033-cpufreq-mediatek-Add-MT8173-cpufreq-driver.patch b/target/linux/mediatek/patches/0033-cpufreq-mediatek-Add-MT8173-cpufreq-driver.patch
new file mode 100644
index 0000000000..81ae4f8275
--- /dev/null
+++ b/target/linux/mediatek/patches/0033-cpufreq-mediatek-Add-MT8173-cpufreq-driver.patch
@@ -0,0 +1,604 @@
+From 2028cb37c941014f6a817d27a867ee1d37ccf2b6 Mon Sep 17 00:00:00 2001
+From: "pi-cheng.chen" <pi-cheng.chen@linaro.org>
+Date: Mon, 8 Jun 2015 20:29:21 +0800
+Subject: [PATCH 33/76] cpufreq: mediatek: Add MT8173 cpufreq driver
+
+This patch implements MT8173 cpufreq driver.
+
+Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
+---
+ drivers/cpufreq/Kconfig.arm | 7 +
+ drivers/cpufreq/Makefile | 1 +
+ drivers/cpufreq/mt8173-cpufreq.c | 550 ++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 558 insertions(+)
+ create mode 100644 drivers/cpufreq/mt8173-cpufreq.c
+
+diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
+index 4f3dbc8..350752b 100644
+--- a/drivers/cpufreq/Kconfig.arm
++++ b/drivers/cpufreq/Kconfig.arm
+@@ -141,6 +141,13 @@ config ARM_KIRKWOOD_CPUFREQ
+ This adds the CPUFreq driver for Marvell Kirkwood
+ SoCs.
+
++config ARM_MT8173_CPUFREQ
++ bool "Mediatek MT8173 CPUFreq support"
++ depends on ARCH_MEDIATEK && REGULATOR
++ select PM_OPP
++ help
++ This adds the CPUFreq driver support for Mediatek MT8173 SoC.
++
+ config ARM_OMAP2PLUS_CPUFREQ
+ bool "TI OMAP2+"
+ depends on ARCH_OMAP2PLUS
+diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
+index cdce92a..97f9a9b 100644
+--- a/drivers/cpufreq/Makefile
++++ b/drivers/cpufreq/Makefile
+@@ -63,6 +63,7 @@ obj-$(CONFIG_ARM_HISI_ACPU_CPUFREQ) += hisi-acpu-cpufreq.o
+ obj-$(CONFIG_ARM_IMX6Q_CPUFREQ) += imx6q-cpufreq.o
+ obj-$(CONFIG_ARM_INTEGRATOR) += integrator-cpufreq.o
+ obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ) += kirkwood-cpufreq.o
++obj-$(CONFIG_ARM_MT8173_CPUFREQ) += mt8173-cpufreq.o
+ obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o
+ obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o
+ obj-$(CONFIG_PXA3xx) += pxa3xx-cpufreq.o
+diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c
+new file mode 100644
+index 0000000..d539e7b
+--- /dev/null
++++ b/drivers/cpufreq/mt8173-cpufreq.c
+@@ -0,0 +1,550 @@
++/*
++ * Copyright (c) 2015 Linaro Ltd.
++ * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
++ *
++ * 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.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ */
++
++#include <linux/clk.h>
++#include <linux/cpu.h>
++#include <linux/cpufreq.h>
++#include <linux/cpumask.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/platform_device.h>
++#include <linux/pm_opp.h>
++#include <linux/regulator/consumer.h>
++#include <linux/slab.h>
++
++#define MIN_VOLT_SHIFT (100000)
++#define MAX_VOLT_SHIFT (200000)
++#define MAX_VOLT_LIMIT (1150000)
++#define VOLT_TOL (10000)
++
++/*
++ * The struct mtk_cpu_dvfs_info holds necessary information for doing CPU DVFS
++ * on each CPU power/clock domain of Mediatek SoCs. Each CPU cluster in
++ * Mediatek SoCs has two voltage inputs, Vproc and Vsram. In some cases the two
++ * voltage inputs need to be controlled under a hardware limitation:
++ * 100mV < Vsram - Vproc < 200mV
++ *
++ * When scaling the clock frequency of a CPU clock domain, the clock source
++ * needs to be switched to another stable PLL clock temporarily until
++ * the original PLL becomes stable at target frequency.
++ */
++struct mtk_cpu_dvfs_info {
++ struct list_head node;
++ cpumask_var_t cpus;
++ struct cpufreq_frequency_table *freq_table;
++ struct device *cpu_dev;
++ struct regulator *proc_reg;
++ struct regulator *sram_reg;
++ struct clk *cpu_clk;
++ struct clk *inter_clk;
++ int intermediate_voltage;
++ bool need_voltage_trace;
++};
++
++static LIST_HEAD(cpu_dvfs_info_list);
++
++static inline struct mtk_cpu_dvfs_info *to_mtk_cpu_dvfs_info(
++ struct list_head *list)
++{
++ return list_entry(list, struct mtk_cpu_dvfs_info, node);
++}
++
++static inline void mtk_cpu_dvfs_info_add(struct mtk_cpu_dvfs_info *info)
++{
++ list_add(&info->node, &cpu_dvfs_info_list);
++}
++
++static struct mtk_cpu_dvfs_info *mtk_cpu_dvfs_info_get(int cpu)
++{
++ struct mtk_cpu_dvfs_info *info;
++ struct list_head *list;
++
++ list_for_each(list, &cpu_dvfs_info_list) {
++ info = to_mtk_cpu_dvfs_info(list);
++
++ if (cpumask_test_cpu(cpu, info->cpus))
++ return info;
++ }
++
++ return NULL;
++}
++
++static void mtk_cpu_dvfs_info_release(void)
++{
++ struct list_head *list, *tmp;
++ struct mtk_cpu_dvfs_info *info;
++
++ list_for_each_safe(list, tmp, &cpu_dvfs_info_list) {
++ info = to_mtk_cpu_dvfs_info(list);
++
++ dev_pm_opp_free_cpufreq_table(info->cpu_dev,
++ &info->freq_table);
++
++ if (!IS_ERR(info->proc_reg))
++ regulator_put(info->proc_reg);
++ if (!IS_ERR(info->sram_reg))
++ regulator_put(info->sram_reg);
++ if (!IS_ERR(info->cpu_clk))
++ clk_put(info->cpu_clk);
++ if (!IS_ERR(info->inter_clk))
++ clk_put(info->inter_clk);
++
++ of_free_opp_table(info->cpu_dev);
++
++ list_del(list);
++ kfree(info);
++ }
++}
++
++#define MIN(a, b) ((a) < (b) ? (a) : (b))
++#define MAX(a, b) ((a) > (b) ? (a) : (b))
++
++static int mtk_cpufreq_voltage_trace(struct mtk_cpu_dvfs_info *info,
++ int new_vproc)
++{
++ struct regulator *proc_reg = info->proc_reg;
++ struct regulator *sram_reg = info->sram_reg;
++ int old_vproc, old_vsram, new_vsram, vsram, vproc, ret;
++
++ old_vproc = regulator_get_voltage(proc_reg);
++ old_vsram = regulator_get_voltage(sram_reg);
++ /* Vsram should not exceed the maximum allowed voltage of SoC. */
++ new_vsram = min(new_vproc + MIN_VOLT_SHIFT, MAX_VOLT_LIMIT);
++
++ if (old_vproc < new_vproc) {
++ /*
++ * When scaling up voltages, Vsram and Vproc scale up step
++ * by step. At each step, set Vsram to (Vproc + 200mV) first,
++ * then set Vproc to (Vsram - 100mV).
++ * Keep doing it until Vsram and Vproc hit target voltages.
++ */
++ do {
++ old_vsram = regulator_get_voltage(sram_reg);
++ old_vproc = regulator_get_voltage(proc_reg);
++
++ vsram = MIN(new_vsram, old_vproc + MAX_VOLT_SHIFT);
++
++ if (vsram + VOLT_TOL >= MAX_VOLT_LIMIT) {
++ vsram = MAX_VOLT_LIMIT;
++
++ /*
++ * If the target Vsram hits the maximum voltage,
++ * try to set the exact voltage value first.
++ */
++ ret = regulator_set_voltage(sram_reg, vsram,
++ vsram);
++ if (ret)
++ ret = regulator_set_voltage(sram_reg,
++ vsram - VOLT_TOL,
++ vsram);
++
++ vproc = new_vproc;
++ } else {
++ ret = regulator_set_voltage(sram_reg, vsram,
++ vsram + VOLT_TOL);
++
++ vproc = vsram - MIN_VOLT_SHIFT;
++ }
++ if (ret)
++ return ret;
++
++ ret = regulator_set_voltage(proc_reg, vproc,
++ vproc + VOLT_TOL);
++ if (ret) {
++ regulator_set_voltage(sram_reg, old_vsram,
++ old_vsram);
++ return ret;
++ }
++ } while (vproc < new_vproc || vsram < new_vsram);
++ } else if (old_vproc > new_vproc) {
++ /*
++ * When scaling down voltages, Vsram and Vproc scale down step
++ * by step. At each step, set Vproc to (Vsram - 200mV) first,
++ * then set Vproc to (Vproc + 100mV).
++ * Keep doing it until Vsram and Vproc hit target voltages.
++ */
++ do {
++ old_vproc = regulator_get_voltage(proc_reg);
++ old_vsram = regulator_get_voltage(sram_reg);
++
++ vproc = MAX(new_vproc, old_vsram - MAX_VOLT_SHIFT);
++ ret = regulator_set_voltage(proc_reg, vproc,
++ vproc + VOLT_TOL);
++ if (ret)
++ return ret;
++
++ if (vproc == new_vproc)
++ vsram = new_vsram;
++ else
++ vsram = MAX(new_vsram, vproc + MIN_VOLT_SHIFT);
++
++ if (vsram + VOLT_TOL >= MAX_VOLT_LIMIT) {
++ vsram = MAX_VOLT_LIMIT;
++
++ /*
++ * If the target Vsram hits the maximum voltage,
++ * try to set the exact voltage value first.
++ */
++ ret = regulator_set_voltage(sram_reg, vsram,
++ vsram);
++ if (ret)
++ ret = regulator_set_voltage(sram_reg,
++ vsram - VOLT_TOL,
++ vsram);
++ } else {
++ ret = regulator_set_voltage(sram_reg, vsram,
++ vsram + VOLT_TOL);
++ }
++
++ if (ret) {
++ regulator_set_voltage(proc_reg, old_vproc,
++ old_vproc);
++ return ret;
++ }
++ } while (vproc > new_vproc + VOLT_TOL ||
++ vsram > new_vsram + VOLT_TOL);
++ }
++
++ return 0;
++}
++
++static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc)
++{
++ if (info->need_voltage_trace)
++ return mtk_cpufreq_voltage_trace(info, vproc);
++ else
++ return regulator_set_voltage(info->proc_reg, vproc,
++ vproc + VOLT_TOL);
++}
++
++static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
++ unsigned int index)
++{
++ struct cpufreq_frequency_table *freq_table = policy->freq_table;
++ struct clk *cpu_clk = policy->clk;
++ struct clk *armpll = clk_get_parent(cpu_clk);
++ struct mtk_cpu_dvfs_info *info = policy->driver_data;
++ struct device *cpu_dev = info->cpu_dev;
++ struct dev_pm_opp *opp;
++ long freq_hz, old_freq_hz;
++ int vproc, old_vproc, inter_vproc, target_vproc, ret;
++
++ inter_vproc = info->intermediate_voltage;
++
++ old_freq_hz = clk_get_rate(cpu_clk);
++ old_vproc = regulator_get_voltage(info->proc_reg);
++
++ freq_hz = freq_table[index].frequency * 1000;
++ rcu_read_lock();
++ opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
++ if (IS_ERR(opp)) {
++ rcu_read_unlock();
++ pr_err("cpu%d: failed to find OPP for %ld\n",
++ policy->cpu, freq_hz);
++ return PTR_ERR(opp);
++ }
++ vproc = dev_pm_opp_get_voltage(opp);
++ rcu_read_unlock();
++
++ /*
++ * If the new voltage or the intermediate voltage is higher than the
++ * current voltage, scale up voltage first.
++ */
++ target_vproc = (inter_vproc > vproc) ? inter_vproc : vproc;
++ if (old_vproc < target_vproc) {
++ ret = mtk_cpufreq_set_voltage(info, target_vproc);
++ if (ret) {
++ pr_err("cpu%d: failed to scale up voltage!\n",
++ policy->cpu);
++ mtk_cpufreq_set_voltage(info, old_vproc);
++ return ret;
++ }
++ }
++
++ /* Reparent the CPU clock to intermediate clock. */
++ ret = clk_set_parent(cpu_clk, info->inter_clk);
++ if (ret) {
++ pr_err("cpu%d: failed to re-parent cpu clock!\n",
++ policy->cpu);
++ mtk_cpufreq_set_voltage(info, old_vproc);
++ WARN_ON(1);
++ return ret;
++ }
++
++ /* Set the original PLL to target rate. */
++ ret = clk_set_rate(armpll, freq_hz);
++ if (ret) {
++ pr_err("cpu%d: failed to scale cpu clock rate!\n",
++ policy->cpu);
++ clk_set_parent(cpu_clk, armpll);
++ mtk_cpufreq_set_voltage(info, old_vproc);
++ return ret;
++ }
++
++ /* Set parent of CPU clock back to the original PLL. */
++ ret = clk_set_parent(cpu_clk, armpll);
++ if (ret) {
++ pr_err("cpu%d: failed to re-parent cpu clock!\n",
++ policy->cpu);
++ mtk_cpufreq_set_voltage(info, inter_vproc);
++ WARN_ON(1);
++ return ret;
++ }
++
++ /*
++ * If the new voltage is lower than the intermediate voltage or the
++ * original voltage, scale down to the new voltage.
++ */
++ if (vproc < inter_vproc || vproc < old_vproc) {
++ ret = mtk_cpufreq_set_voltage(info, vproc);
++ if (ret) {
++ pr_err("cpu%d: failed to scale down voltage!\n",
++ policy->cpu);
++ clk_set_parent(cpu_clk, info->inter_clk);
++ clk_set_rate(armpll, old_freq_hz);
++ clk_set_parent(cpu_clk, armpll);
++ return ret;
++ }
++ }
++
++ return 0;
++}
++
++static int mtk_cpufreq_init(struct cpufreq_policy *policy)
++{
++ struct mtk_cpu_dvfs_info *info;
++ int ret;
++
++ info = mtk_cpu_dvfs_info_get(policy->cpu);
++ if (!info) {
++ pr_err("%s: mtk cpu dvfs info for cpu%d is not initialized\n",
++ __func__, policy->cpu);
++ return -ENODEV;
++ }
++
++ ret = cpufreq_table_validate_and_show(policy, info->freq_table);
++ if (ret) {
++ pr_err("%s: invalid frequency table: %d\n", __func__, ret);
++ return ret;
++ }
++
++ cpumask_copy(policy->cpus, info->cpus);
++ policy->driver_data = info;
++ policy->clk = info->cpu_clk;
++
++ return 0;
++}
++
++static struct cpufreq_driver mt8173_cpufreq_driver = {
++ .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
++ .verify = cpufreq_generic_frequency_table_verify,
++ .target_index = mtk_cpufreq_set_target,
++ .get = cpufreq_generic_get,
++ .init = mtk_cpufreq_init,
++ .name = "mtk-cpufreq",
++ .attr = cpufreq_generic_attr,
++};
++
++static int mtk_cpu_dvfs_info_init(int cpu)
++{
++ struct device *cpu_dev;
++ struct regulator *proc_reg = ERR_PTR(-ENODEV);
++ struct regulator *sram_reg = ERR_PTR(-ENODEV);
++ struct clk *cpu_clk = ERR_PTR(-ENODEV);
++ struct clk *inter_clk = ERR_PTR(-ENODEV);
++ struct mtk_cpu_dvfs_info *info;
++ struct cpufreq_frequency_table *freq_table;
++ struct dev_pm_opp *opp;
++ unsigned long rate;
++ int ret;
++
++ cpu_dev = get_cpu_device(cpu);
++ if (!cpu_dev) {
++ pr_err("failed to get cpu%d device\n", cpu);
++ return -ENODEV;
++ }
++
++ ret = of_init_opp_table(cpu_dev);
++ if (ret) {
++ pr_warn("no OPP table for cpu%d\n", cpu);
++ return ret;
++ }
++
++ cpu_clk = clk_get(cpu_dev, "cpu");
++ if (IS_ERR(cpu_clk)) {
++ if (PTR_ERR(cpu_clk) == -EPROBE_DEFER)
++ pr_warn("cpu clk for cpu%d not ready, retry.\n", cpu);
++ else
++ pr_err("failed to get cpu clk for cpu%d\n", cpu);
++
++ ret = PTR_ERR(cpu_clk);
++ goto out_free_opp_table;
++ }
++
++ inter_clk = clk_get(cpu_dev, "intermediate");
++ if (IS_ERR(inter_clk)) {
++ if (PTR_ERR(inter_clk) == -EPROBE_DEFER)
++ pr_warn("intermediate clk for cpu%d not ready, retry.\n",
++ cpu);
++ else
++ pr_err("failed to get intermediate clk for cpu%d\n",
++ cpu);
++
++ ret = PTR_ERR(cpu_clk);
++ goto out_free_resources;
++ }
++
++ proc_reg = regulator_get_exclusive(cpu_dev, "proc");
++ if (IS_ERR(proc_reg)) {
++ if (PTR_ERR(proc_reg) == -EPROBE_DEFER)
++ pr_warn("proc regulator for cpu%d not ready, retry.\n",
++ cpu);
++ else
++ pr_err("failed to get proc regulator for cpu%d\n",
++ cpu);
++
++ ret = PTR_ERR(proc_reg);
++ goto out_free_resources;
++ }
++
++ /* Both presence and absence of sram regulator are valid cases. */
++ sram_reg = regulator_get_exclusive(cpu_dev, "sram");
++
++ info = kzalloc(sizeof(*info), GFP_KERNEL);
++ if (!info) {
++ ret = -ENOMEM;
++ goto out_free_resources;
++ }
++
++ ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
++ if (ret) {
++ pr_err("failed to init cpufreq table for cpu%d: %d\n",
++ cpu, ret);
++ goto out_free_mtk_cpu_dvfs_info;
++ }
++
++ if (!alloc_cpumask_var(&info->cpus, GFP_KERNEL))
++ goto out_free_cpufreq_table;
++
++ /* Search a safe voltage for intermediate frequency. */
++ rate = clk_get_rate(inter_clk);
++ rcu_read_lock();
++ opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
++ if (IS_ERR(opp)) {
++ pr_err("failed to get intermediate opp for cpu%d\n", cpu);
++ ret = PTR_ERR(opp);
++ goto out_free_cpumask;
++ }
++ info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
++ rcu_read_unlock();
++
++ /* CPUs in the same cluster share a clock and power domain. */
++ cpumask_copy(info->cpus, &cpu_topology[cpu].core_sibling);
++
++ info->cpu_dev = cpu_dev;
++ info->proc_reg = proc_reg;
++ info->sram_reg = IS_ERR(sram_reg) ? NULL : sram_reg;
++ info->cpu_clk = cpu_clk;
++ info->inter_clk = inter_clk;
++ info->freq_table = freq_table;
++
++ /*
++ * If SRAM regulator is present, software "voltage trace" is needed
++ * for this CPU power domain.
++ */
++ info->need_voltage_trace = !IS_ERR(sram_reg);
++
++ mtk_cpu_dvfs_info_add(info);
++
++ return 0;
++
++out_free_cpumask:
++ free_cpumask_var(info->cpus);
++
++out_free_cpufreq_table:
++ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
++
++out_free_mtk_cpu_dvfs_info:
++ kfree(info);
++
++out_free_resources:
++ if (!IS_ERR(proc_reg))
++ regulator_put(proc_reg);
++ if (!IS_ERR(sram_reg))
++ regulator_put(sram_reg);
++ if (!IS_ERR(cpu_clk))
++ clk_put(cpu_clk);
++ if (!IS_ERR(inter_clk))
++ clk_put(inter_clk);
++
++out_free_opp_table:
++ of_free_opp_table(cpu_dev);
++
++ return ret;
++}
++
++static int mt8173_cpufreq_probe(struct platform_device *pdev)
++{
++ int cpu, ret;
++
++ for_each_possible_cpu(cpu) {
++ /*
++ * If the struct mtk_cpu_dvfs_info for the cpu power domain
++ * is already initialized, skip this CPU.
++ */
++ if (!mtk_cpu_dvfs_info_get(cpu)) {
++ ret = mtk_cpu_dvfs_info_init(cpu);
++ if (ret) {
++ if (ret != -EPROBE_DEFER)
++ pr_err("%s probe fail\n", __func__);
++
++ mtk_cpu_dvfs_info_release();
++ return ret;
++ }
++ }
++ }
++
++ ret = cpufreq_register_driver(&mt8173_cpufreq_driver);
++ if (ret) {
++ pr_err("failed to register mtk cpufreq driver\n");
++ mtk_cpu_dvfs_info_release();
++ }
++
++ return ret;
++}
++
++static struct platform_driver mt8173_cpufreq_platdrv = {
++ .driver = {
++ .name = "mt8173-cpufreq",
++ },
++ .probe = mt8173_cpufreq_probe,
++};
++module_platform_driver(mt8173_cpufreq_platdrv);
++
++static int mt8173_cpufreq_driver_init(void)
++{
++ struct platform_device *pdev;
++
++ if (!of_machine_is_compatible("mediatek,mt8173"))
++ return -ENODEV;
++
++ pdev = platform_device_register_simple("mt8173-cpufreq", -1, NULL, 0);
++ if (IS_ERR(pdev)) {
++ pr_err("failed to register mtk-cpufreq platform device\n");
++ return PTR_ERR(pdev);
++ }
++
++ return 0;
++}
++module_init(mt8173_cpufreq_driver_init);
+--
+1.7.10.4
+