This patch adds dvfs support for exynos5440 SOC. This soc has 4 cores and
they scale at same frequency. The nature of exynos5440 clock controller is
different from previous exynos controllers so not using the common exynos
cpufreq framework. The major difference being interrupt notfication for
frequency change. Also, OPP library is used for device tree parsing to get
different parameters like frequency, voltage etc. Since the opp library sorts
the frequency table in ascending order so they are again re-arranged in
descending order. This will have one-to-one mapping with the clock controller
state management logic.
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
Changes in V3:
* Converted the driver to probe based as suggested by Viresh. This is also
beneficial for multiplatform kernel.
* Other coding guidelines related changes.
Changes in V2:
* Added OPP library support to parse DT parameters.
* Removed a hack to handle interrupts in bootup.
* Implemented other review comments from Viresh and Inder.
All these patches are dependent on Thomas Abraham common clock patches.
(http://www.mail-archive.com/[email protected]/msg15860.html)
This whole patch series is based on 3.9-rc1.
.../bindings/cpufreq/cpufreq-exynos5440.txt | 29 ++
drivers/cpufreq/Kconfig.arm | 9 +
drivers/cpufreq/Makefile | 1 +
drivers/cpufreq/exynos5440-cpufreq.c | 467 ++++++++++++++++++++
4 files changed, 506 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt
create mode 100644 drivers/cpufreq/exynos5440-cpufreq.c
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt
new file mode 100644
index 0000000..a0dbe0b
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt
@@ -0,0 +1,29 @@
+
+Exynos5440 cpufreq driver
+-------------------
+
+Exynos5440 SoC cpufreq driver for CPU frequency scaling.
+
+Required properties:
+- interrupts: Interrupt to know the completion of cpu frequency change.
+- operating-points: Table of frequencies and voltage CPU could be transitioned into,
+ in the decreasing order. Frequency should be in KHZ units and voltage
+ should be in microvolts.
+
+Optional properties:
+- clock-latency: Clock monitor latency in microsecond.
+
+All the required listed above must be defined under node cpufreq.
+
+Example:
+--------
+ cpufreq@160000 {
+ compatible = "samsung,exynos5440-cpufreq";
+ reg = <0x160000 0x1000>;
+ interrupts = <0 57 0>;
+ operating-points = <
+ 1000000 975000
+ 800000 925000>;
+ clock-latency = <100000>;
+ };
+
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 030ddf6..7ed9c4a 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -77,6 +77,15 @@ config ARM_EXYNOS5250_CPUFREQ
This adds the CPUFreq driver for Samsung EXYNOS5250
SoC.
+config ARM_EXYNOS5440_CPUFREQ
+ def_bool SOC_EXYNOS5440
+ depends on HAVE_CLK && PM_OPP && OF
+ help
+ This adds the CPUFreq driver for Samsung EXYNOS5440
+ SoC. The nature of exynos5440 clock controller is
+ different than previous exynos controllers so not using
+ the common exynos framework.
+
config ARM_KIRKWOOD_CPUFREQ
def_bool ARCH_KIRKWOOD && OF
help
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 863fd18..c841438 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_ARM_EXYNOS_CPUFREQ) += exynos-cpufreq.o
obj-$(CONFIG_ARM_EXYNOS4210_CPUFREQ) += exynos4210-cpufreq.o
obj-$(CONFIG_ARM_EXYNOS4X12_CPUFREQ) += exynos4x12-cpufreq.o
obj-$(CONFIG_ARM_EXYNOS5250_CPUFREQ) += exynos5250-cpufreq.o
+obj-$(CONFIG_ARM_EXYNOS5440_CPUFREQ) += exynos5440-cpufreq.o
obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ) += kirkwood-cpufreq.o
obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o
obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o
diff --git a/drivers/cpufreq/exynos5440-cpufreq.c b/drivers/cpufreq/exynos5440-cpufreq.c
new file mode 100644
index 0000000..ea3d46d
--- /dev/null
+++ b/drivers/cpufreq/exynos5440-cpufreq.c
@@ -0,0 +1,467 @@
+/*
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Amit Daniel Kachhap <[email protected]>
+ *
+ * EXYNOS5440 - CPU frequency scaling support
+ *
+ * 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.
+*/
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/opp.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* Register definations */
+#define XMU_DVFS_CTRL 0x0060
+#define XMU_PMU_P0_7 0x0064
+#define XMU_C0_3_PSTATE 0x0090
+#define XMU_P_LIMIT 0x00A0
+#define XMU_P_STATUS 0x00A4
+#define XMU_PMUEVTEN 0x00D0
+#define XMU_PMUIRQEN 0x00D4
+#define XMU_PMUIRQ 0x00D8
+
+/* PMU mask and shift definations */
+#define P_VALUE_MASK 0x7
+
+#define XMU_DVFS_CTRL_EN_SHIFT 0
+
+#define P0_7_CPUCLKDEV_SHIFT 21
+#define P0_7_CPUCLKDEV_MASK 0x7
+#define P0_7_ATBCLKDEV_SHIFT 18
+#define P0_7_ATBCLKDEV_MASK 0x7
+#define P0_7_CSCLKDEV_SHIFT 15
+#define P0_7_CSCLKDEV_MASK 0x7
+#define P0_7_CPUEMA_SHIFT 28
+#define P0_7_CPUEMA_MASK 0xf
+#define P0_7_L2EMA_SHIFT 24
+#define P0_7_L2EMA_MASK 0xf
+#define P0_7_VDD_SHIFT 8
+#define P0_7_VDD_MASK 0x7f
+#define P0_7_FREQ_SHIFT 0
+#define P0_7_FREQ_MASK 0xff
+
+#define C0_3_PSTATE_VALID_SHIFT 8
+#define C0_3_PSTATE_CURR_SHIFT 4
+#define C0_3_PSTATE_NEW_SHIFT 0
+
+#define PSTATE_CHANGED_EVTEN_SHIFT 0
+
+#define PSTATE_CHANGED_IRQEN_SHIFT 0
+
+#define PSTATE_CHANGED_SHIFT 0
+
+/* some constant values for clock divider calculation */
+#define CPU_DIV_FREQ_MAX 500
+#define CPU_DBG_FREQ_MAX 375
+#define CPU_ATB_FREQ_MAX 500
+
+#define PMIC_LOW_VOLT 0x30
+#define PMIC_HIGH_VOLT 0x28
+
+#define CPUEMA_HIGH 0x2
+#define CPUEMA_MID 0x4
+#define CPUEMA_LOW 0x7
+
+#define L2EMA_HIGH 0x1
+#define L2EMA_MID 0x3
+#define L2EMA_LOW 0x4
+
+#define DIV_TAB_MAX 2
+/* frequency unit is 20MHZ */
+#define FREQ_UNIT 20
+#define MAX_VOLTAGE 1550000 /* In micro volt */
+#define VOLTAGE_STEP 12500 /* In micro volt */
+
+#define CPUFREQ_NAME "exynos5440_dvfs"
+#define DEF_TRANS_LATENCY 100000
+
+enum cpufreq_level_index {
+ L0, L1, L2, L3, L4,
+ L5, L6, L7, L8, L9,
+};
+#define CPUFREQ_LEVEL_END (L7 + 1)
+
+struct exynos_dvfs_data {
+ void __iomem *base;
+ struct resource *mem;
+ int irq;
+ struct clk *cpu_clk;
+ unsigned int cur_frequency;
+ unsigned int latency;
+ struct cpufreq_frequency_table *freq_table;
+ unsigned int freq_count;
+ struct device *dev;
+ bool dvfs_enable;
+ struct work_struct irq_work;
+};
+
+static struct exynos_dvfs_data *dvfs_info;
+static DEFINE_MUTEX(cpufreq_lock);
+static struct cpufreq_freqs freqs;
+
+static int init_div_table(void)
+{
+ struct cpufreq_frequency_table *freq_tbl = dvfs_info->freq_table;
+ unsigned int tmp, clk_div, ema_div, freq, volt_id;
+ int i = 0;
+ struct opp *opp;
+
+ for (i = 0; freq_tbl[i].frequency != CPUFREQ_TABLE_END; i++) {
+
+ opp = opp_find_freq_exact(dvfs_info->dev,
+ freq_tbl[i].frequency * 1000, true);
+ if (IS_ERR(opp)) {
+ pr_err("failed to find valid OPP for %u KHZ\n",
+ freq_tbl[i].frequency);
+ return PTR_ERR(opp);
+ }
+
+ freq = freq_tbl[i].frequency / 1000; /* In MHZ */
+ clk_div = ((freq / CPU_DIV_FREQ_MAX) & P0_7_CPUCLKDEV_MASK)
+ << P0_7_CPUCLKDEV_SHIFT;
+ clk_div |= ((freq / CPU_ATB_FREQ_MAX) & P0_7_ATBCLKDEV_MASK)
+ << P0_7_ATBCLKDEV_SHIFT;
+ clk_div |= ((freq / CPU_DBG_FREQ_MAX) & P0_7_CSCLKDEV_MASK)
+ << P0_7_CSCLKDEV_SHIFT;
+
+ /* Calculate EMA */
+ volt_id = opp_get_voltage(opp);
+ volt_id = (MAX_VOLTAGE - volt_id) / VOLTAGE_STEP;
+ if (volt_id < PMIC_HIGH_VOLT) {
+ ema_div = (CPUEMA_HIGH << P0_7_CPUEMA_SHIFT) |
+ (L2EMA_HIGH << P0_7_L2EMA_SHIFT);
+ } else if (volt_id > PMIC_LOW_VOLT) {
+ ema_div = (CPUEMA_LOW << P0_7_CPUEMA_SHIFT) |
+ (L2EMA_LOW << P0_7_L2EMA_SHIFT);
+ } else {
+ ema_div = (CPUEMA_MID << P0_7_CPUEMA_SHIFT) |
+ (L2EMA_MID << P0_7_L2EMA_SHIFT);
+ }
+
+ tmp = (clk_div | ema_div | (volt_id << P0_7_VDD_SHIFT)
+ | ((freq / FREQ_UNIT) << P0_7_FREQ_SHIFT));
+
+ __raw_writel(tmp, dvfs_info->base + XMU_PMU_P0_7 + 4 * i);
+ }
+
+ return 0;
+}
+
+static void exynos_enable_dvfs(void)
+{
+ unsigned int tmp, i, cpu;
+ struct cpufreq_frequency_table *freq_table = dvfs_info->freq_table;
+ /* Disable DVFS */
+ __raw_writel(0, dvfs_info->base + XMU_DVFS_CTRL);
+
+ /* Enable PSTATE Change Event */
+ tmp = __raw_readl(dvfs_info->base + XMU_PMUEVTEN);
+ tmp |= (1 << PSTATE_CHANGED_EVTEN_SHIFT);
+ __raw_writel(tmp, dvfs_info->base + XMU_PMUEVTEN);
+
+ /* Enable PSTATE Change IRQ */
+ tmp = __raw_readl(dvfs_info->base + XMU_PMUIRQEN);
+ tmp |= (1 << PSTATE_CHANGED_IRQEN_SHIFT);
+ __raw_writel(tmp, dvfs_info->base + XMU_PMUIRQEN);
+
+ /* Set initial performance index */
+ for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++)
+ if (freq_table[i].frequency == dvfs_info->cur_frequency)
+ break;
+
+ if (freq_table[i].frequency == CPUFREQ_TABLE_END) {
+ pr_crit("Boot up frequency not supported\n");
+ /* Assign the highest frequency */
+ i = 0;
+ dvfs_info->cur_frequency = freq_table[i].frequency;
+ }
+
+ pr_info("Setting dvfs initial frequency = %uKHZ",
+ dvfs_info->cur_frequency);
+
+ for (cpu = 0; cpu < CONFIG_NR_CPUS; cpu++) {
+ tmp = __raw_readl(dvfs_info->base + XMU_C0_3_PSTATE + cpu * 4);
+ tmp &= ~(P_VALUE_MASK << C0_3_PSTATE_NEW_SHIFT);
+ tmp |= (i << C0_3_PSTATE_NEW_SHIFT);
+ __raw_writel(tmp, dvfs_info->base + XMU_C0_3_PSTATE + cpu * 4);
+ }
+
+ /* Enable DVFS */
+ __raw_writel(1 << XMU_DVFS_CTRL_EN_SHIFT,
+ dvfs_info->base + XMU_DVFS_CTRL);
+}
+
+static int exynos_verify_speed(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy,
+ dvfs_info->freq_table);
+}
+
+static unsigned int exynos_getspeed(unsigned int cpu)
+{
+ return dvfs_info->cur_frequency;
+}
+
+static int exynos_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int index, tmp;
+ int ret = 0, i;
+ struct cpufreq_frequency_table *freq_table = dvfs_info->freq_table;
+
+ mutex_lock(&cpufreq_lock);
+ freqs.old = dvfs_info->cur_frequency;
+
+ if (cpufreq_frequency_table_target(policy, freq_table,
+ target_freq, relation, &index)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ freqs.new = freq_table[index].frequency;
+ freqs.cpu = policy->cpu;
+
+ for_each_cpu(freqs.cpu, policy->cpus)
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ /* Set the target frequency in all C0_3_PSTATE register */
+ for_each_cpu(i, policy->cpus) {
+ tmp = __raw_readl(dvfs_info->base + XMU_C0_3_PSTATE + i * 4);
+ tmp &= ~(P_VALUE_MASK << C0_3_PSTATE_NEW_SHIFT);
+ tmp |= (index << C0_3_PSTATE_NEW_SHIFT);
+
+ __raw_writel(tmp, dvfs_info->base + XMU_C0_3_PSTATE + i * 4);
+ }
+out:
+ mutex_unlock(&cpufreq_lock);
+ return ret;
+}
+
+static void exynos_cpufreq_work(struct work_struct *work)
+{
+ unsigned int cur_pstate, index;
+ struct cpufreq_policy *policy = cpufreq_cpu_get(0); /* boot CPU */
+ struct cpufreq_frequency_table *freq_table = dvfs_info->freq_table;
+
+ /* Ensure we can access cpufreq structures */
+ if (unlikely(dvfs_info->dvfs_enable == false))
+ goto skip_work;
+
+ mutex_lock(&cpufreq_lock);
+ freqs.old = dvfs_info->cur_frequency;
+
+ cur_pstate = __raw_readl(dvfs_info->base + XMU_P_STATUS);
+ if (cur_pstate >> C0_3_PSTATE_VALID_SHIFT & 0x1)
+ index = (cur_pstate >> C0_3_PSTATE_CURR_SHIFT) & P_VALUE_MASK;
+ else
+ index = (cur_pstate >> C0_3_PSTATE_NEW_SHIFT) & P_VALUE_MASK;
+
+ if (likely(index < dvfs_info->freq_count)) {
+ freqs.new = freq_table[index].frequency;
+ for_each_cpu(freqs.cpu, policy->cpus)
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ dvfs_info->cur_frequency = freqs.new;
+ } else {
+ pr_crit("New frequency out of range\n");
+ }
+
+ cpufreq_cpu_put(policy);
+ mutex_unlock(&cpufreq_lock);
+skip_work:
+ enable_irq(dvfs_info->irq);
+}
+
+static irqreturn_t exynos_cpufreq_irq(int irq, void *id)
+{
+ unsigned int tmp;
+
+ tmp = __raw_readl(dvfs_info->base + XMU_PMUIRQ);
+ if (tmp >> PSTATE_CHANGED_SHIFT & 0x1) {
+ __raw_writel(tmp, dvfs_info->base + XMU_PMUIRQ);
+ disable_irq_nosync(irq);
+ schedule_work(&dvfs_info->irq_work);
+ }
+ return IRQ_HANDLED;
+}
+
+static void exynos_sort_descend_freq_table(void)
+{
+ struct cpufreq_frequency_table *freq_tbl = dvfs_info->freq_table;
+ int i = 0, index;
+ unsigned int tmp_freq;
+
+ /*
+ * Freq table is already in ascending order as it is created from
+ * OPP library, so just swap the elements to make it descending.
+ */
+ for (i = 0; i < dvfs_info->freq_count / 2; i++) {
+ index = dvfs_info->freq_count - i - 1;
+ tmp_freq = freq_tbl[i].frequency;
+ freq_tbl[i].frequency = freq_tbl[index].frequency;
+ freq_tbl[index].frequency = tmp_freq;
+ }
+}
+
+static int exynos_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ policy->cur = dvfs_info->cur_frequency;
+ cpufreq_frequency_table_get_attr(dvfs_info->freq_table, policy->cpu);
+
+ /* set the transition latency value */
+ policy->cpuinfo.transition_latency = dvfs_info->latency;
+
+ cpumask_setall(policy->cpus);
+
+ return cpufreq_frequency_table_cpuinfo(policy, dvfs_info->freq_table);
+}
+
+static struct cpufreq_driver exynos_driver = {
+ .flags = CPUFREQ_STICKY,
+ .verify = exynos_verify_speed,
+ .target = exynos_target,
+ .get = exynos_getspeed,
+ .init = exynos_cpufreq_cpu_init,
+ .name = CPUFREQ_NAME,
+};
+
+static int exynos_cpufreq_probe(struct platform_device *pdev)
+{
+ int ret = -EINVAL;
+ struct device_node *np;
+ struct resource res;
+
+ np = of_find_compatible_node(NULL, NULL, "samsung,exynos5440-cpufreq");
+ if (!np)
+ return -ENODEV;
+
+ dvfs_info = devm_kzalloc(&pdev->dev, sizeof(*dvfs_info), GFP_KERNEL);
+ if (!dvfs_info) {
+ ret = -ENOMEM;
+ goto err_put_node;
+ }
+
+ dvfs_info->dev = &pdev->dev;
+ dvfs_info->dev->of_node = np;
+
+ ret = of_address_to_resource(np, 0, &res);
+ if (ret)
+ goto err_put_node;
+
+ dvfs_info->base = devm_ioremap(dvfs_info->dev, res.start,
+ resource_size(&res));
+ if (!dvfs_info->base) {
+ pr_err("No cpufreq memory map found\n");
+ ret = -ENODEV;
+ goto err_put_node;
+ }
+
+ dvfs_info->irq = irq_of_parse_and_map(np, 0);
+ if (dvfs_info->irq == 0) {
+ pr_err("No cpufreq irq found\n");
+ ret = -ENODEV;
+ goto err_put_node;
+ }
+
+ ret = of_init_opp_table(dvfs_info->dev);
+ if (ret) {
+ pr_err("failed to init OPP table: %d\n", ret);
+ goto err_put_node;
+ }
+
+ ret = opp_init_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
+ if (ret) {
+ pr_err("failed to init cpufreq table: %d\n", ret);
+ goto err_put_node;
+ }
+ dvfs_info->freq_count = opp_get_opp_count(dvfs_info->dev);
+ exynos_sort_descend_freq_table();
+
+ if (of_property_read_u32(np, "clock-latency", &dvfs_info->latency))
+ dvfs_info->latency = DEF_TRANS_LATENCY;
+
+ dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
+ if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
+ pr_err("Failed to get cpu clock\n");
+ ret = PTR_ERR(dvfs_info->cpu_clk);
+ goto err_free_table;
+ }
+
+ dvfs_info->cur_frequency = clk_get_rate(dvfs_info->cpu_clk);
+ if (!dvfs_info->cur_frequency) {
+ pr_err("Failed to get clock rate\n");
+ ret = -EINVAL;
+ goto err_free_table;
+ }
+ dvfs_info->cur_frequency /= 1000;
+
+ INIT_WORK(&dvfs_info->irq_work, exynos_cpufreq_work);
+ if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
+ IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
+ pr_err("Failed to register IRQ\n");
+ ret = -ENODEV;
+ goto err_free_table;
+ }
+
+ ret = init_div_table();
+ if (ret) {
+ pr_err("Failed to initialise div table\n");
+ goto err_free_table;
+ }
+
+ exynos_enable_dvfs();
+ ret = cpufreq_register_driver(&exynos_driver);
+ if (ret) {
+ pr_err("%s: failed to register cpufreq driver\n", __func__);
+ goto err_free_table;
+ }
+
+ of_node_put(np);
+ dvfs_info->dvfs_enable = true;
+ pr_info("exynos5440 DVFS initialized.\n");
+ return 0;
+
+err_free_table:
+ opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
+err_put_node:
+ of_node_put(np);
+ pr_err("%s: failed initialization\n", __func__);
+ return ret;
+}
+
+static int exynos_cpufreq_remove(struct platform_device *pdev)
+{
+ cpufreq_unregister_driver(&exynos_driver);
+ opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
+ return 0;
+}
+
+static struct platform_driver exynos_cpufreq_platdrv = {
+ .driver = {
+ .name = "exynos5440-cpufreq",
+ .owner = THIS_MODULE,
+ },
+ .probe = exynos_cpufreq_probe,
+ .remove = exynos_cpufreq_remove,
+};
+module_platform_driver(exynos_cpufreq_platdrv);
+
+MODULE_AUTHOR("Amit Daniel Kachhap <[email protected]>");
+MODULE_DESCRIPTION("Exynos5440 cpufreq driver");
+MODULE_LICENSE("GPL");
--
1.7.1
This patch helps to have single binary for exynos5440 and previous
exynos soc's. This change is needed for adding exynos5440 cpufreq driver
which does not uses exynos-cpufreq common file and adds it own driver.
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
drivers/cpufreq/exynos-cpufreq.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
index 78057a3..ee75997 100644
--- a/drivers/cpufreq/exynos-cpufreq.c
+++ b/drivers/cpufreq/exynos-cpufreq.c
@@ -297,7 +297,7 @@ static int __init exynos_cpufreq_init(void)
else if (soc_is_exynos5250())
ret = exynos5250_cpufreq_init(exynos_info);
else
- pr_err("%s: CPU type not found\n", __func__);
+ return 0;
if (ret)
goto err_vdd_arm;
--
1.7.1
The OPP library support is needed for exynos5440 cpu frequency
dynamic scaling driver.
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
arch/arm/mach-exynos/Kconfig | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
index 70f94c8..d5dde07 100644
--- a/arch/arm/mach-exynos/Kconfig
+++ b/arch/arm/mach-exynos/Kconfig
@@ -72,10 +72,12 @@ config SOC_EXYNOS5440
bool "SAMSUNG EXYNOS5440"
default y
depends on ARCH_EXYNOS5
+ select ARCH_HAS_OPP
select ARM_ARCH_TIMER
select AUTO_ZRELADDR
select PINCTRL
select PINCTRL_EXYNOS5440
+ select PM_OPP
help
Enable EXYNOS5440 SoC support
--
1.7.1
Add cpufreq controller device node for Exynos5440 SoC for passing
parameters like controller base address, interrupt and cpufreq
table. This node is added outside cpu0 as this driver is now a platform
driver and a new device structure is needed.
Signed-off-by: Amit Daniel Kachhap <[email protected]>
---
Changes in V3:
* Moved the DT node outside cpu0 node as the driver is now a platform
driver.
arch/arm/boot/dts/exynos5440.dtsi | 12 ++++++++++++
arch/arm/mach-exynos/mach-exynos5-dt.c | 2 ++
2 files changed, 14 insertions(+), 0 deletions(-)
diff --git a/arch/arm/boot/dts/exynos5440.dtsi b/arch/arm/boot/dts/exynos5440.dtsi
index 5f3562a..4b29a5a 100644
--- a/arch/arm/boot/dts/exynos5440.dtsi
+++ b/arch/arm/boot/dts/exynos5440.dtsi
@@ -63,6 +63,18 @@
};
+ cpufreq@160000 {
+ compatible = "samsung,exynos5440-cpufreq";
+ reg = <0x160000 0x1000>;
+ interrupts = <0 57 0>;
+ operating-points = <
+ /* KHZ uV */
+ 1200000 1025000
+ 1000000 975000
+ 800000 925000
+ >;
+ };
+
serial@B0000 {
compatible = "samsung,exynos4210-uart";
reg = <0xB0000 0x1000>;
diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c
index acaeb14..0a446c4 100644
--- a/arch/arm/mach-exynos/mach-exynos5-dt.c
+++ b/arch/arm/mach-exynos/mach-exynos5-dt.c
@@ -145,6 +145,8 @@ static const struct of_dev_auxdata exynos5250_auxdata_lookup[] __initconst = {
static const struct of_dev_auxdata exynos5440_auxdata_lookup[] __initconst = {
OF_DEV_AUXDATA("samsung,exynos4210-uart", EXYNOS5440_PA_UART0,
"exynos4210-uart.0", NULL),
+ OF_DEV_AUXDATA("samsung,exynos5440-cpufreq", 0x160000,
+ "exynos5440-cpufreq", NULL),
{},
};
--
1.7.1
On 03/07/2013 05:13 AM, Amit Daniel Kachhap wrote:
> +/* Register definations */
s/definations/definitions
> +#define XMU_DVFS_CTRL 0x0060
> +#define XMU_PMU_P0_7 0x0064
> +#define XMU_C0_3_PSTATE 0x0090
> +#define XMU_P_LIMIT 0x00A0
> +#define XMU_P_STATUS 0x00A4
> +#define XMU_PMUEVTEN 0x00D0
> +#define XMU_PMUIRQEN 0x00D4
> +#define XMU_PMUIRQ 0x00D8
Keeping all hex numbers lower case might be a good idea.
> +
> +/* PMU mask and shift definations */
> +#define P_VALUE_MASK 0x7
> +
> +#define XMU_DVFS_CTRL_EN_SHIFT 0
> +
> +#define P0_7_CPUCLKDEV_SHIFT 21
> +#define P0_7_CPUCLKDEV_MASK 0x7
> +#define P0_7_ATBCLKDEV_SHIFT 18
> +#define P0_7_ATBCLKDEV_MASK 0x7
> +#define P0_7_CSCLKDEV_SHIFT 15
> +#define P0_7_CSCLKDEV_MASK 0x7
> +#define P0_7_CPUEMA_SHIFT 28
> +#define P0_7_CPUEMA_MASK 0xf
> +#define P0_7_L2EMA_SHIFT 24
> +#define P0_7_L2EMA_MASK 0xf
...
> +static int exynos_cpufreq_probe(struct platform_device *pdev)
> +{
> + int ret = -EINVAL;
> + struct device_node *np;
> + struct resource res;
> +
> + np = of_find_compatible_node(NULL, NULL, "samsung,exynos5440-cpufreq");
> + if (!np)
> + return -ENODEV;
> +
> + dvfs_info = devm_kzalloc(&pdev->dev, sizeof(*dvfs_info), GFP_KERNEL);
> + if (!dvfs_info) {
> + ret = -ENOMEM;
> + goto err_put_node;
> + }
> +
> + dvfs_info->dev = &pdev->dev;
> + dvfs_info->dev->of_node = np;
> +
> + ret = of_address_to_resource(np, 0, &res);
> + if (ret)
> + goto err_put_node;
> +
> + dvfs_info->base = devm_ioremap(dvfs_info->dev, res.start,
There is a devm_ioremap_resource() function that has been introduced
recently. It could simplify this code a bit and is preferred over
devm_ioremap().
> + resource_size(&res));
> + if (!dvfs_info->base) {
> + pr_err("No cpufreq memory map found\n");
> + ret = -ENODEV;
> + goto err_put_node;
> + }
> +
> + dvfs_info->irq = irq_of_parse_and_map(np, 0);
> + if (dvfs_info->irq == 0) {
> + pr_err("No cpufreq irq found\n");
Wouldn't dev_err() be more appropriate here ?
> + ret = -ENODEV;
> + goto err_put_node;
> + }
> +
> + ret = of_init_opp_table(dvfs_info->dev);
> + if (ret) {
> + pr_err("failed to init OPP table: %d\n", ret);
> + goto err_put_node;
> + }
> +
> + ret = opp_init_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
> + if (ret) {
> + pr_err("failed to init cpufreq table: %d\n", ret);
> + goto err_put_node;
> + }
> + dvfs_info->freq_count = opp_get_opp_count(dvfs_info->dev);
> + exynos_sort_descend_freq_table();
> +
> + if (of_property_read_u32(np, "clock-latency", &dvfs_info->latency))
> + dvfs_info->latency = DEF_TRANS_LATENCY;
> +
> + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
> + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
devm_clk_get() return value needs to be checked with IS_ERR(),
not IS_ERR_OR_NULL().
> + pr_err("Failed to get cpu clock\n");
> + ret = PTR_ERR(dvfs_info->cpu_clk);
> + goto err_free_table;
> + }
> +
> + dvfs_info->cur_frequency = clk_get_rate(dvfs_info->cpu_clk);
> + if (!dvfs_info->cur_frequency) {
> + pr_err("Failed to get clock rate\n");
> + ret = -EINVAL;
> + goto err_free_table;
> + }
> + dvfs_info->cur_frequency /= 1000;
> +
> + INIT_WORK(&dvfs_info->irq_work, exynos_cpufreq_work);
> + if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
> + IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
> + pr_err("Failed to register IRQ\n");
> + ret = -ENODEV;
> + goto err_free_table;
> + }
> +
> + ret = init_div_table();
> + if (ret) {
> + pr_err("Failed to initialise div table\n");
> + goto err_free_table;
> + }
> +
> + exynos_enable_dvfs();
> + ret = cpufreq_register_driver(&exynos_driver);
> + if (ret) {
> + pr_err("%s: failed to register cpufreq driver\n", __func__);
> + goto err_free_table;
> + }
> +
> + of_node_put(np);
> + dvfs_info->dvfs_enable = true;
> + pr_info("exynos5440 DVFS initialized.\n");
dev_info() ?
> + return 0;
> +
> +err_free_table:
> + opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
> +err_put_node:
> + of_node_put(np);
> + pr_err("%s: failed initialization\n", __func__);
Is this really needed ? This failure will be logged by the driver core
anyway.
> + return ret;
> +
On Thu, Mar 07, 2013 at 04:28:00PM +0100, Sylwester Nawrocki wrote:
> On 03/07/2013 05:13 AM, Amit Daniel Kachhap wrote:
> > + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
> > + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
>
> devm_clk_get() return value needs to be checked with IS_ERR(),
> not IS_ERR_OR_NULL().
>
> > + pr_err("Failed to get cpu clock\n");
> > + ret = PTR_ERR(dvfs_info->cpu_clk);
> > + goto err_free_table;
Amit, to illustrate why this is wrong, consider this:
1. Set cpu_clk to NULL.
2. Realise IS_ERR_OR_NULL(NULL) is true.
3. What is the value of PTR_ERR(NULL) ?
4. What effect does that have when you jump to err_free_table ?
5. What value is returned from this function in that case ?
6. What does that return value mean to the driver core ?
On 7 March 2013 12:13, Amit Daniel Kachhap <[email protected]> wrote:
> diff --git a/drivers/cpufreq/exynos5440-cpufreq.c b/drivers/cpufreq/exynos5440-cpufreq.c
> +struct exynos_dvfs_data {
> + void __iomem *base;
> + struct resource *mem;
> + int irq;
> + struct clk *cpu_clk;
> + unsigned int cur_frequency;
> + unsigned int latency;
> + struct cpufreq_frequency_table *freq_table;
> + unsigned int freq_count;
> + struct device *dev;
> + bool dvfs_enable;
s/enable/enabled?
> +static int exynos_cpufreq_probe(struct platform_device *pdev)
> + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
> + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
s/IS_ERR_OR_NULL/IS_ERR
> + if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
> + IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
> + pr_err("Failed to register IRQ\n");
> + ret = -ENODEV;
use the value returned from this function rather than creating your
own.. true for all
other calls too, unless they return NULL on error.
> +}
Hi Sylwester,
Thanks for the review. Will update with your suggestion in the next version,
Thanks,
Amit D
On Thu, Mar 7, 2013 at 8:58 PM, Sylwester Nawrocki
<[email protected]> wrote:
> On 03/07/2013 05:13 AM, Amit Daniel Kachhap wrote:
>> +/* Register definations */
>
> s/definations/definitions
ok
>
>> +#define XMU_DVFS_CTRL 0x0060
>> +#define XMU_PMU_P0_7 0x0064
>> +#define XMU_C0_3_PSTATE 0x0090
>> +#define XMU_P_LIMIT 0x00A0
>> +#define XMU_P_STATUS 0x00A4
>> +#define XMU_PMUEVTEN 0x00D0
>> +#define XMU_PMUIRQEN 0x00D4
>> +#define XMU_PMUIRQ 0x00D8
>
> Keeping all hex numbers lower case might be a good idea.
Ok
>
>> +
>> +/* PMU mask and shift definations */
>> +#define P_VALUE_MASK 0x7
>> +
>> +#define XMU_DVFS_CTRL_EN_SHIFT 0
>> +
>> +#define P0_7_CPUCLKDEV_SHIFT 21
>> +#define P0_7_CPUCLKDEV_MASK 0x7
>> +#define P0_7_ATBCLKDEV_SHIFT 18
>> +#define P0_7_ATBCLKDEV_MASK 0x7
>> +#define P0_7_CSCLKDEV_SHIFT 15
>> +#define P0_7_CSCLKDEV_MASK 0x7
>> +#define P0_7_CPUEMA_SHIFT 28
>> +#define P0_7_CPUEMA_MASK 0xf
>> +#define P0_7_L2EMA_SHIFT 24
>> +#define P0_7_L2EMA_MASK 0xf
> ...
>> +static int exynos_cpufreq_probe(struct platform_device *pdev)
>> +{
>> + int ret = -EINVAL;
>> + struct device_node *np;
>> + struct resource res;
>> +
>> + np = of_find_compatible_node(NULL, NULL, "samsung,exynos5440-cpufreq");
>> + if (!np)
>> + return -ENODEV;
>> +
>> + dvfs_info = devm_kzalloc(&pdev->dev, sizeof(*dvfs_info), GFP_KERNEL);
>> + if (!dvfs_info) {
>> + ret = -ENOMEM;
>> + goto err_put_node;
>> + }
>> +
>> + dvfs_info->dev = &pdev->dev;
>> + dvfs_info->dev->of_node = np;
>> +
>> + ret = of_address_to_resource(np, 0, &res);
>> + if (ret)
>> + goto err_put_node;
>> +
>> + dvfs_info->base = devm_ioremap(dvfs_info->dev, res.start,
>
> There is a devm_ioremap_resource() function that has been introduced
> recently. It could simplify this code a bit and is preferred over
> devm_ioremap().
yes right. I somehow missed this api.
>
>> + resource_size(&res));
>> + if (!dvfs_info->base) {
>> + pr_err("No cpufreq memory map found\n");
>> + ret = -ENODEV;
>> + goto err_put_node;
>> + }
>> +
>> + dvfs_info->irq = irq_of_parse_and_map(np, 0);
>> + if (dvfs_info->irq == 0) {
>> + pr_err("No cpufreq irq found\n");
>
> Wouldn't dev_err() be more appropriate here ?
Ok
>
>> + ret = -ENODEV;
>> + goto err_put_node;
>> + }
>> +
>> + ret = of_init_opp_table(dvfs_info->dev);
>> + if (ret) {
>> + pr_err("failed to init OPP table: %d\n", ret);
>> + goto err_put_node;
>> + }
>> +
>> + ret = opp_init_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
>> + if (ret) {
>> + pr_err("failed to init cpufreq table: %d\n", ret);
>> + goto err_put_node;
>> + }
>> + dvfs_info->freq_count = opp_get_opp_count(dvfs_info->dev);
>> + exynos_sort_descend_freq_table();
>> +
>> + if (of_property_read_u32(np, "clock-latency", &dvfs_info->latency))
>> + dvfs_info->latency = DEF_TRANS_LATENCY;
>> +
>> + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
>> + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
>
> devm_clk_get() return value needs to be checked with IS_ERR(),
> not IS_ERR_OR_NULL().
ok
>
>> + pr_err("Failed to get cpu clock\n");
>> + ret = PTR_ERR(dvfs_info->cpu_clk);
>> + goto err_free_table;
>> + }
>> +
>> + dvfs_info->cur_frequency = clk_get_rate(dvfs_info->cpu_clk);
>> + if (!dvfs_info->cur_frequency) {
>> + pr_err("Failed to get clock rate\n");
>> + ret = -EINVAL;
>> + goto err_free_table;
>> + }
>> + dvfs_info->cur_frequency /= 1000;
>> +
>> + INIT_WORK(&dvfs_info->irq_work, exynos_cpufreq_work);
>> + if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
>> + IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
>> + pr_err("Failed to register IRQ\n");
>> + ret = -ENODEV;
>> + goto err_free_table;
>> + }
>> +
>> + ret = init_div_table();
>> + if (ret) {
>> + pr_err("Failed to initialise div table\n");
>> + goto err_free_table;
>> + }
>> +
>> + exynos_enable_dvfs();
>> + ret = cpufreq_register_driver(&exynos_driver);
>> + if (ret) {
>> + pr_err("%s: failed to register cpufreq driver\n", __func__);
>> + goto err_free_table;
>> + }
>> +
>> + of_node_put(np);
>> + dvfs_info->dvfs_enable = true;
>> + pr_info("exynos5440 DVFS initialized.\n");
>
> dev_info() ?
>
>> + return 0;
>> +
>> +err_free_table:
>> + opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
>> +err_put_node:
>> + of_node_put(np);
>> + pr_err("%s: failed initialization\n", __func__);
>
> Is this really needed ? This failure will be logged by the driver core
> anyway.
>
>> + return ret;
>> +
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Russell,
On Thu, Mar 7, 2013 at 9:07 PM, Russell King - ARM Linux
<[email protected]> wrote:
> On Thu, Mar 07, 2013 at 04:28:00PM +0100, Sylwester Nawrocki wrote:
>> On 03/07/2013 05:13 AM, Amit Daniel Kachhap wrote:
>> > + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
>> > + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
>>
>> devm_clk_get() return value needs to be checked with IS_ERR(),
>> not IS_ERR_OR_NULL().
>>
>> > + pr_err("Failed to get cpu clock\n");
>> > + ret = PTR_ERR(dvfs_info->cpu_clk);
>> > + goto err_free_table;
>
> Amit, to illustrate why this is wrong, consider this:
> 1. Set cpu_clk to NULL.
> 2. Realise IS_ERR_OR_NULL(NULL) is true.
> 3. What is the value of PTR_ERR(NULL) ?
> 4. What effect does that have when you jump to err_free_table ?
> 5. What value is returned from this function in that case ?
> 6. What does that return value mean to the driver core ?
Thanks for the detailed explaination. Usage of IS_ERR_OR_NULL is not
suitable here.
Thanks,
Amit D
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
Hi Viresh,
On Sat, Mar 9, 2013 at 4:17 PM, Viresh Kumar <[email protected]> wrote:
> On 7 March 2013 12:13, Amit Daniel Kachhap <[email protected]> wrote:
>> diff --git a/drivers/cpufreq/exynos5440-cpufreq.c b/drivers/cpufreq/exynos5440-cpufreq.c
>> +struct exynos_dvfs_data {
>> + void __iomem *base;
>> + struct resource *mem;
>> + int irq;
>> + struct clk *cpu_clk;
>> + unsigned int cur_frequency;
>> + unsigned int latency;
>> + struct cpufreq_frequency_table *freq_table;
>> + unsigned int freq_count;
>> + struct device *dev;
>> + bool dvfs_enable;
>
> s/enable/enabled?
Ok
>
>> +static int exynos_cpufreq_probe(struct platform_device *pdev)
>
>> + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
>> + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
>
> s/IS_ERR_OR_NULL/IS_ERR
Ok.
>
>> + if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
>> + IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
>> + pr_err("Failed to register IRQ\n");
>> + ret = -ENODEV;
>
> use the value returned from this function rather than creating your
> own.. true for all
> other calls too, unless they return NULL on error.
>
Will integrate your suggestions in the next version.
Thanks,
Amit D
>> +}
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html