diff options
author | Viresh Kumar <viresh.kumar@linaro.org> | 2013-04-04 12:54:20 (GMT) |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-04-10 11:19:25 (GMT) |
commit | ab423e435f1eafdb9a071fe8a9942b2522d09d2d (patch) | |
tree | 43f5ccf512b0bdcec471c6f3713e7b0b1497492a /drivers/cpufreq | |
parent | 8e8aa95a2b0b2b0184b3b72b324a6145362720bd (diff) | |
download | linux-ab423e435f1eafdb9a071fe8a9942b2522d09d2d.tar.xz |
cpufreq: ia64: move cpufreq driver to drivers/cpufreq
This patch moves cpufreq driver of IA64 architecture to drivers/cpufreq.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq')
-rw-r--r-- | drivers/cpufreq/Kconfig | 17 | ||||
-rw-r--r-- | drivers/cpufreq/Makefile | 1 | ||||
-rw-r--r-- | drivers/cpufreq/ia64-acpi-cpufreq.c | 438 |
3 files changed, 456 insertions, 0 deletions
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig index d7ce6cc..a2f1600 100644 --- a/drivers/cpufreq/Kconfig +++ b/drivers/cpufreq/Kconfig @@ -218,6 +218,23 @@ config AVR32_AT32AP_CPUFREQ endmenu +menu "CPUFreq processor drivers" +depends on IA64 + +config IA64_ACPI_CPUFREQ + tristate "ACPI Processor P-States driver" + select CPU_FREQ_TABLE + depends on ACPI_PROCESSOR + help + This driver adds a CPUFreq driver which utilizes the ACPI + Processor Performance States. + + For details, take a look at <file:Documentation/cpu-freq/>. + + If in doubt, say N. + +endmenu + menu "PowerPC CPU frequency scaling drivers" depends on PPC32 || PPC64 source "drivers/cpufreq/Kconfig.powerpc" diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 2d6dbf3..ab68133 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -81,3 +81,4 @@ obj-$(CONFIG_AVR32_AT32AP_CPUFREQ) += at32ap-cpufreq.o obj-$(CONFIG_BLACKFIN) += blackfin-cpufreq.o obj-$(CONFIG_CRIS_MACH_ARTPEC3) += cris-artpec3-cpufreq.o obj-$(CONFIG_ETRAXFS) += cris-etraxfs-cpufreq.o +obj-$(CONFIG_IA64_ACPI_CPUFREQ) += ia64-acpi-cpufreq.o diff --git a/drivers/cpufreq/ia64-acpi-cpufreq.c b/drivers/cpufreq/ia64-acpi-cpufreq.c new file mode 100644 index 0000000..c0075db --- /dev/null +++ b/drivers/cpufreq/ia64-acpi-cpufreq.c @@ -0,0 +1,438 @@ +/* + * This file provides the ACPI based P-state support. This + * module works with generic cpufreq infrastructure. Most of + * the code is based on i386 version + * (arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c) + * + * Copyright (C) 2005 Intel Corp + * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/cpufreq.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <asm/io.h> +#include <asm/uaccess.h> +#include <asm/pal.h> + +#include <linux/acpi.h> +#include <acpi/processor.h> + +MODULE_AUTHOR("Venkatesh Pallipadi"); +MODULE_DESCRIPTION("ACPI Processor P-States Driver"); +MODULE_LICENSE("GPL"); + + +struct cpufreq_acpi_io { + struct acpi_processor_performance acpi_data; + struct cpufreq_frequency_table *freq_table; + unsigned int resume; +}; + +static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS]; + +static struct cpufreq_driver acpi_cpufreq_driver; + + +static int +processor_set_pstate ( + u32 value) +{ + s64 retval; + + pr_debug("processor_set_pstate\n"); + + retval = ia64_pal_set_pstate((u64)value); + + if (retval) { + pr_debug("Failed to set freq to 0x%x, with error 0x%lx\n", + value, retval); + return -ENODEV; + } + return (int)retval; +} + + +static int +processor_get_pstate ( + u32 *value) +{ + u64 pstate_index = 0; + s64 retval; + + pr_debug("processor_get_pstate\n"); + + retval = ia64_pal_get_pstate(&pstate_index, + PAL_GET_PSTATE_TYPE_INSTANT); + *value = (u32) pstate_index; + + if (retval) + pr_debug("Failed to get current freq with " + "error 0x%lx, idx 0x%x\n", retval, *value); + + return (int)retval; +} + + +/* To be used only after data->acpi_data is initialized */ +static unsigned +extract_clock ( + struct cpufreq_acpi_io *data, + unsigned value, + unsigned int cpu) +{ + unsigned long i; + + pr_debug("extract_clock\n"); + + for (i = 0; i < data->acpi_data.state_count; i++) { + if (value == data->acpi_data.states[i].status) + return data->acpi_data.states[i].core_frequency; + } + return data->acpi_data.states[i-1].core_frequency; +} + + +static unsigned int +processor_get_freq ( + struct cpufreq_acpi_io *data, + unsigned int cpu) +{ + int ret = 0; + u32 value = 0; + cpumask_t saved_mask; + unsigned long clock_freq; + + pr_debug("processor_get_freq\n"); + + saved_mask = current->cpus_allowed; + set_cpus_allowed_ptr(current, cpumask_of(cpu)); + if (smp_processor_id() != cpu) + goto migrate_end; + + /* processor_get_pstate gets the instantaneous frequency */ + ret = processor_get_pstate(&value); + + if (ret) { + set_cpus_allowed_ptr(current, &saved_mask); + printk(KERN_WARNING "get performance failed with error %d\n", + ret); + ret = 0; + goto migrate_end; + } + clock_freq = extract_clock(data, value, cpu); + ret = (clock_freq*1000); + +migrate_end: + set_cpus_allowed_ptr(current, &saved_mask); + return ret; +} + + +static int +processor_set_freq ( + struct cpufreq_acpi_io *data, + struct cpufreq_policy *policy, + int state) +{ + int ret = 0; + u32 value = 0; + struct cpufreq_freqs cpufreq_freqs; + cpumask_t saved_mask; + int retval; + + pr_debug("processor_set_freq\n"); + + saved_mask = current->cpus_allowed; + set_cpus_allowed_ptr(current, cpumask_of(policy->cpu)); + if (smp_processor_id() != policy->cpu) { + retval = -EAGAIN; + goto migrate_end; + } + + if (state == data->acpi_data.state) { + if (unlikely(data->resume)) { + pr_debug("Called after resume, resetting to P%d\n", state); + data->resume = 0; + } else { + pr_debug("Already at target state (P%d)\n", state); + retval = 0; + goto migrate_end; + } + } + + pr_debug("Transitioning from P%d to P%d\n", + data->acpi_data.state, state); + + /* cpufreq frequency struct */ + cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency; + cpufreq_freqs.new = data->freq_table[state].frequency; + + /* notify cpufreq */ + cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_PRECHANGE); + + /* + * First we write the target state's 'control' value to the + * control_register. + */ + + value = (u32) data->acpi_data.states[state].control; + + pr_debug("Transitioning to state: 0x%08x\n", value); + + ret = processor_set_pstate(value); + if (ret) { + unsigned int tmp = cpufreq_freqs.new; + cpufreq_notify_transition(policy, &cpufreq_freqs, + CPUFREQ_POSTCHANGE); + cpufreq_freqs.new = cpufreq_freqs.old; + cpufreq_freqs.old = tmp; + cpufreq_notify_transition(policy, &cpufreq_freqs, + CPUFREQ_PRECHANGE); + cpufreq_notify_transition(policy, &cpufreq_freqs, + CPUFREQ_POSTCHANGE); + printk(KERN_WARNING "Transition failed with error %d\n", ret); + retval = -ENODEV; + goto migrate_end; + } + + cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_POSTCHANGE); + + data->acpi_data.state = state; + + retval = 0; + +migrate_end: + set_cpus_allowed_ptr(current, &saved_mask); + return (retval); +} + + +static unsigned int +acpi_cpufreq_get ( + unsigned int cpu) +{ + struct cpufreq_acpi_io *data = acpi_io_data[cpu]; + + pr_debug("acpi_cpufreq_get\n"); + + return processor_get_freq(data, cpu); +} + + +static int +acpi_cpufreq_target ( + struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) +{ + struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; + unsigned int next_state = 0; + unsigned int result = 0; + + pr_debug("acpi_cpufreq_setpolicy\n"); + + result = cpufreq_frequency_table_target(policy, + data->freq_table, target_freq, relation, &next_state); + if (result) + return (result); + + result = processor_set_freq(data, policy, next_state); + + return (result); +} + + +static int +acpi_cpufreq_verify ( + struct cpufreq_policy *policy) +{ + unsigned int result = 0; + struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; + + pr_debug("acpi_cpufreq_verify\n"); + + result = cpufreq_frequency_table_verify(policy, + data->freq_table); + + return (result); +} + + +static int +acpi_cpufreq_cpu_init ( + struct cpufreq_policy *policy) +{ + unsigned int i; + unsigned int cpu = policy->cpu; + struct cpufreq_acpi_io *data; + unsigned int result = 0; + + pr_debug("acpi_cpufreq_cpu_init\n"); + + data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL); + if (!data) + return (-ENOMEM); + + acpi_io_data[cpu] = data; + + result = acpi_processor_register_performance(&data->acpi_data, cpu); + + if (result) + goto err_free; + + /* capability check */ + if (data->acpi_data.state_count <= 1) { + pr_debug("No P-States\n"); + result = -ENODEV; + goto err_unreg; + } + + if ((data->acpi_data.control_register.space_id != + ACPI_ADR_SPACE_FIXED_HARDWARE) || + (data->acpi_data.status_register.space_id != + ACPI_ADR_SPACE_FIXED_HARDWARE)) { + pr_debug("Unsupported address space [%d, %d]\n", + (u32) (data->acpi_data.control_register.space_id), + (u32) (data->acpi_data.status_register.space_id)); + result = -ENODEV; + goto err_unreg; + } + + /* alloc freq_table */ + data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * + (data->acpi_data.state_count + 1), + GFP_KERNEL); + if (!data->freq_table) { + result = -ENOMEM; + goto err_unreg; + } + + /* detect transition latency */ + policy->cpuinfo.transition_latency = 0; + for (i=0; i<data->acpi_data.state_count; i++) { + if ((data->acpi_data.states[i].transition_latency * 1000) > + policy->cpuinfo.transition_latency) { + policy->cpuinfo.transition_latency = + data->acpi_data.states[i].transition_latency * 1000; + } + } + policy->cur = processor_get_freq(data, policy->cpu); + + /* table init */ + for (i = 0; i <= data->acpi_data.state_count; i++) + { + data->freq_table[i].index = i; + if (i < data->acpi_data.state_count) { + data->freq_table[i].frequency = + data->acpi_data.states[i].core_frequency * 1000; + } else { + data->freq_table[i].frequency = CPUFREQ_TABLE_END; + } + } + + result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table); + if (result) { + goto err_freqfree; + } + + /* notify BIOS that we exist */ + acpi_processor_notify_smm(THIS_MODULE); + + printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management " + "activated.\n", cpu); + + for (i = 0; i < data->acpi_data.state_count; i++) + pr_debug(" %cP%d: %d MHz, %d mW, %d uS, %d uS, 0x%x 0x%x\n", + (i == data->acpi_data.state?'*':' '), i, + (u32) data->acpi_data.states[i].core_frequency, + (u32) data->acpi_data.states[i].power, + (u32) data->acpi_data.states[i].transition_latency, + (u32) data->acpi_data.states[i].bus_master_latency, + (u32) data->acpi_data.states[i].status, + (u32) data->acpi_data.states[i].control); + + cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu); + + /* the first call to ->target() should result in us actually + * writing something to the appropriate registers. */ + data->resume = 1; + + return (result); + + err_freqfree: + kfree(data->freq_table); + err_unreg: + acpi_processor_unregister_performance(&data->acpi_data, cpu); + err_free: + kfree(data); + acpi_io_data[cpu] = NULL; + + return (result); +} + + +static int +acpi_cpufreq_cpu_exit ( + struct cpufreq_policy *policy) +{ + struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; + + pr_debug("acpi_cpufreq_cpu_exit\n"); + + if (data) { + cpufreq_frequency_table_put_attr(policy->cpu); + acpi_io_data[policy->cpu] = NULL; + acpi_processor_unregister_performance(&data->acpi_data, + policy->cpu); + kfree(data); + } + + return (0); +} + + +static struct freq_attr* acpi_cpufreq_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + NULL, +}; + + +static struct cpufreq_driver acpi_cpufreq_driver = { + .verify = acpi_cpufreq_verify, + .target = acpi_cpufreq_target, + .get = acpi_cpufreq_get, + .init = acpi_cpufreq_cpu_init, + .exit = acpi_cpufreq_cpu_exit, + .name = "acpi-cpufreq", + .owner = THIS_MODULE, + .attr = acpi_cpufreq_attr, +}; + + +static int __init +acpi_cpufreq_init (void) +{ + pr_debug("acpi_cpufreq_init\n"); + + return cpufreq_register_driver(&acpi_cpufreq_driver); +} + + +static void __exit +acpi_cpufreq_exit (void) +{ + pr_debug("acpi_cpufreq_exit\n"); + + cpufreq_unregister_driver(&acpi_cpufreq_driver); + return; +} + + +late_initcall(acpi_cpufreq_init); +module_exit(acpi_cpufreq_exit); + |