Hi Inder, Thanks for the review, On Wed, Feb 6, 2013 at 9:09 PM, Inderpal Singh <inderpal.singh@xxxxxxxxxx> wrote: > On 7 February 2013 01:09, Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx> wrote: >> This patch adds dvfs support for exynos5440 SOC. The nature of exynos5440 >> clock controller is different from previous exynos controllers so not using >> the common exynos cpufreq framework. Also, the device tree parsing is added >> to get different parameters like frequency, voltage etc. >> >> Signed-off-by: Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx> >> --- >> .../bindings/cpufreq/cpufreq-exynos5440.txt | 24 ++ >> drivers/cpufreq/Kconfig.arm | 8 + >> drivers/cpufreq/Makefile | 1 + >> drivers/cpufreq/exynos5440-cpufreq.c | 448 ++++++++++++++++++++ >> 4 files changed, 481 insertions(+) >> 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..96cb0ed >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-exynos5440.txt >> @@ -0,0 +1,24 @@ >> + >> +Exynos5440 cpufreq driver >> +------------------- >> + >> +Exynos5440 SoC cpufreq driver for CPU frequency scaling. >> + >> +Required properties: >> +- interrupts: Interrupt to know the completion of cpu frequency change. >> +- cpufreq_tbl: 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. >> + >> +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>; >> + cpufreq_tbl = < 1200000 1025000 >> + 1000000 975000 >> + 800000 925000 >; >> + }; >> diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm >> index a0b3661..554756f 100644 >> --- a/drivers/cpufreq/Kconfig.arm >> +++ b/drivers/cpufreq/Kconfig.arm >> @@ -77,6 +77,14 @@ config ARM_EXYNOS5250_CPUFREQ >> This adds the CPUFreq driver for Samsung EXYNOS5250 >> SoC. >> >> +config ARM_EXYNOS5440_CPUFREQ >> + def_bool SOC_EXYNOS5440 >> + 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_SPEAR_CPUFREQ >> bool "SPEAr CPUFreq support" >> depends on PLAT_SPEAR >> diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile >> index fadc4d4..5159ba4 100644 >> --- a/drivers/cpufreq/Makefile >> +++ b/drivers/cpufreq/Makefile >> @@ -50,6 +50,7 @@ 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_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..41d39e2 >> --- /dev/null >> +++ b/drivers/cpufreq/exynos5440-cpufreq.c >> @@ -0,0 +1,448 @@ >> +/* >> + * Copyright (c) 2013 Samsung Electronics Co., Ltd. >> + * http://www.samsung.com >> + * >> + * Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx> >> + * >> + * 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. >> +*/ >> + >> +#include <linux/clk.h> >> +#include <linux/cpufreq.h> >> +#include <linux/err.h> >> +#include <linux/interrupt.h> >> +#include <linux/io.h> >> +#include <linux/of_address.h> >> +#include <linux/of_irq.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 DRIVER_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; >> + bool dvfs_init; >> + struct cpufreq_frequency_table *freq_table; >> + struct work_struct irq_work; >> +}; >> + >> +static struct exynos_dvfs_data *dvfs_info; >> +static DEFINE_MUTEX(cpufreq_lock); >> +static struct cpufreq_freqs freqs; >> +static struct cpufreq_frequency_table exynos_freq_table[CPUFREQ_LEVEL_END + 1]; >> +static unsigned int exynos_volt_table[CPUFREQ_LEVEL_END + 1]; >> + >> +static void init_div_table(void) >> +{ >> + struct cpufreq_frequency_table *freq_tbl = exynos_freq_table; >> + unsigned int *volt_tbl = exynos_volt_table; >> + unsigned int tmp, clk_div, ema_div, freq, volt_id; >> + int i = 0; >> + >> + for (i = 0; freq_tbl[i].frequency != CPUFREQ_TABLE_END; i++) { >> + >> + 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 = (MAX_VOLTAGE - volt_tbl[i]) / 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); >> + } >> +} >> + >> +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 perfromance 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"); >> + if (i) { >> + /*Assign the highest frequency*/ >> + i = 0; >> + dvfs_info->cur_frequency = freq_table[i].frequency; >> + } else { >> + return; >> + } >> + } >> + pr_info("Setting dvfs initial frequency = %u", >> + 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, old_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 (dvfs_info->dvfs_init == false) { >> + ret = -EAGAIN; >> + goto out; >> + } >> + >> + /* >> + * The policy max have been changed so that we cannot get proper >> + * old_index with cpufreq_frequency_table_target(). Thus, ignore >> + * policy and get the index from the raw freqeuncy table. >> + */ >> + for (old_index = 0; >> + freq_table[old_index].frequency != CPUFREQ_TABLE_END; >> + old_index++) >> + if (freq_table[old_index].frequency == freqs.old) >> + break; >> + >> + if (freq_table[old_index].frequency == CPUFREQ_TABLE_END) { >> + ret = -EINVAL; >> + goto out; >> + } >> + >> + 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; >> + >> + 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 (index < CPUFREQ_LEVEL_END) >> + 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; >> + >> + cpufreq_cpu_put(policy); >> + mutex_unlock(&cpufreq_lock); >> + 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); >> + >> + if (dvfs_info->dvfs_init == true) { >> + disable_irq_nosync(irq); >> + schedule_work(&dvfs_info->irq_work); >> + } >> + } >> + return IRQ_HANDLED; >> +} >> + >> +static int exynos_cpufreq_cpu_init(struct cpufreq_policy *policy) >> +{ >> + policy->cur = policy->min = policy->max = dvfs_info->cur_frequency; >> + >> + cpufreq_frequency_table_get_attr(dvfs_info->freq_table, policy->cpu); >> + >> + /* set the transition latency value */ >> + policy->cpuinfo.transition_latency = DEF_TRANS_LATENCY; > > transition_latency can be provided through DT. Yes I also thought but all previous exynos cpufreq driver uses the same constant value so didn't create dt node. > >> + >> + /* >> + * EXYNOS5440 multi-core processors has 4 cores >> + * that the frequency cannot be set independently. >> + * Each cpu is bound to the same speed. >> + * So the affected cpu is all of the cpus. >> + */ >> + if (num_online_cpus() == 1) { >> + cpumask_copy(policy->related_cpus, cpu_possible_mask); >> + cpumask_copy(policy->cpus, cpu_online_mask); >> + } else { >> + policy->shared_type = CPUFREQ_SHARED_TYPE_ANY; >> + 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 = DRIVER_NAME, >> +}; >> + > > Since this driver is only for exynos5440, having the same names as > common exynos-cpufreq is misleading. Yes your suggestion is good but the names like exynos5440_* looks very long. > >> +static int __init exynos_cpufreq_init(void) >> +{ >> + int ret = -EINVAL, len, i; >> + struct device_node *np; >> + struct cpufreq_frequency_table *freq_tbl = exynos_freq_table; >> + unsigned int *volt_tbl = exynos_volt_table; >> + const struct property *prop; >> + const __be32 *val; >> + >> + np = of_find_compatible_node(NULL, NULL, "samsung,exynos5440-cpufreq"); >> + if (!np) >> + return -ENODEV; >> + >> + dvfs_info = kzalloc(sizeof(struct exynos_dvfs_data), GFP_KERNEL); >> + if (!dvfs_info) { >> + of_node_put(np); >> + return -ENOMEM; >> + } >> + >> + dvfs_info->base = of_iomap(np, 0); >> + if (!dvfs_info->base) { >> + pr_err("No cpufreq memory map found\n"); >> + ret = -ENODEV; >> + goto err_map; >> + >> + } >> + >> + 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_irq_parse; >> + } >> + >> + prop = of_find_property(np, "cpufreq_tbl", NULL); >> + if (!prop || !prop->value) { >> + pr_err("No cpufreq table found\n"); >> + ret = -ENODEV; >> + goto err_irq_parse; >> + } >> + >> + len = prop->length / sizeof(u32); >> + val = prop->value; >> + >> + if ((len == 0) || (len / 2 > CPUFREQ_LEVEL_END)) { >> + pr_err("Invalid cpufreq table\n"); >> + ret = -ENODEV; >> + goto err_irq_parse; >> + } >> + >> + for (i = 0; i < (len / 2); i++) { >> + freq_tbl[i].index = i; >> + freq_tbl[i].frequency = be32_to_cpup(val++); >> + volt_tbl[i] = be32_to_cpup(val++); >> + } >> + >> + freq_tbl[i].index = i; >> + freq_tbl[i].frequency = CPUFREQ_TABLE_END; > > How about using OPP library to allocate and setup freqtable ? It will > clean up this code and you wont have to have a statically allocated > exynos_freq_table. Ok I will check for this. Thanks, Amit > > Thanks, > Inder > >> + >> + dvfs_info->freq_table = freq_tbl; >> + >> + dvfs_info->cpu_clk = clk_get(NULL, "armclk"); >> + if (IS_ERR(dvfs_info->cpu_clk)) { >> + pr_err("Failed to get cpu clock\n"); >> + ret = PTR_ERR(dvfs_info->cpu_clk); >> + goto err_irq_parse; >> + } >> + >> + INIT_WORK(&dvfs_info->irq_work, exynos_cpufreq_work); >> + if (request_irq(dvfs_info->irq, exynos_cpufreq_irq, >> + IRQF_TRIGGER_NONE, DRIVER_NAME, dvfs_info)) { >> + pr_err("Failed to register IRQ\n"); >> + ret = -ENODEV; >> + goto err_irq_req; >> + } >> + >> + dvfs_info->cur_frequency = clk_get_rate(dvfs_info->cpu_clk) / 1000; >> + init_div_table(); >> + exynos_enable_dvfs(); >> + >> + if (cpufreq_register_driver(&exynos_driver)) { >> + pr_err("%s: failed to register cpufreq driver\n", __func__); >> + goto err_register; >> + } >> + >> + of_node_put(np); >> + dvfs_info->dvfs_init = true; >> + pr_info("exynos5440 DVFS initialised.\n"); >> + >> + return 0; >> + >> +err_register: >> + free_irq(dvfs_info->irq, dvfs_info); >> +err_irq_req: >> + clk_put(dvfs_info->cpu_clk); >> +err_irq_parse: >> + iounmap(dvfs_info->base); >> +err_map: >> + of_node_put(np); >> + kfree(dvfs_info); >> + pr_err("%s: failed initialization\n", __func__); >> + return -EINVAL; >> +} >> +late_initcall(exynos_cpufreq_init); >> -- >> 1.7.10.4 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html