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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/cpufreq/ia64-acpi-cpufreq.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/cpufreq/ia64-acpi-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/ia64-acpi-cpufreq.c | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/drivers/cpufreq/ia64-acpi-cpufreq.c b/drivers/cpufreq/ia64-acpi-cpufreq.c new file mode 100644 index 000000000..c6bdc4555 --- /dev/null +++ b/drivers/cpufreq/ia64-acpi-cpufreq.c @@ -0,0 +1,353 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#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 <asm/io.h> +#include <linux/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; + unsigned int resume; +}; + +struct cpufreq_acpi_req { + unsigned int cpu; + unsigned int state; +}; + +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%llx\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%llx, 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 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 long +processor_get_freq ( + void *arg) +{ + struct cpufreq_acpi_req *req = arg; + unsigned int cpu = req->cpu; + struct cpufreq_acpi_io *data = acpi_io_data[cpu]; + u32 value; + int ret; + + pr_debug("processor_get_freq\n"); + if (smp_processor_id() != cpu) + return -EAGAIN; + + /* processor_get_pstate gets the instantaneous frequency */ + ret = processor_get_pstate(&value); + if (ret) { + pr_warn("get performance failed with error %d\n", ret); + return ret; + } + return 1000 * extract_clock(data, value); +} + + +static long +processor_set_freq ( + void *arg) +{ + struct cpufreq_acpi_req *req = arg; + unsigned int cpu = req->cpu; + struct cpufreq_acpi_io *data = acpi_io_data[cpu]; + int ret, state = req->state; + u32 value; + + pr_debug("processor_set_freq\n"); + if (smp_processor_id() != cpu) + return -EAGAIN; + + 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); + return 0; + } + } + + pr_debug("Transitioning from P%d to P%d\n", + data->acpi_data.state, state); + + /* + * 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) { + pr_warn("Transition failed with error %d\n", ret); + return -ENODEV; + } + + data->acpi_data.state = state; + return 0; +} + + +static unsigned int +acpi_cpufreq_get ( + unsigned int cpu) +{ + struct cpufreq_acpi_req req; + long ret; + + req.cpu = cpu; + ret = work_on_cpu(cpu, processor_get_freq, &req); + + return ret > 0 ? (unsigned int) ret : 0; +} + + +static int +acpi_cpufreq_target ( + struct cpufreq_policy *policy, + unsigned int index) +{ + struct cpufreq_acpi_req req; + + req.cpu = policy->cpu; + req.state = index; + + return work_on_cpu(req.cpu, processor_set_freq, &req); +} + +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; + struct cpufreq_frequency_table *freq_table; + + pr_debug("acpi_cpufreq_cpu_init\n"); + + data = kzalloc(sizeof(*data), 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 */ + freq_table = kcalloc(data->acpi_data.state_count + 1, + sizeof(*freq_table), + GFP_KERNEL); + if (!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; + } + } + + /* table init */ + for (i = 0; i <= data->acpi_data.state_count; i++) + { + if (i < data->acpi_data.state_count) { + freq_table[i].frequency = + data->acpi_data.states[i].core_frequency * 1000; + } else { + freq_table[i].frequency = CPUFREQ_TABLE_END; + } + } + + policy->freq_table = freq_table; + + /* notify BIOS that we exist */ + acpi_processor_notify_smm(THIS_MODULE); + + pr_info("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); + + /* the first call to ->target() should result in us actually + * writing something to the appropriate registers. */ + data->resume = 1; + + return (result); + + err_unreg: + acpi_processor_unregister_performance(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) { + acpi_io_data[policy->cpu] = NULL; + acpi_processor_unregister_performance(policy->cpu); + kfree(policy->freq_table); + kfree(data); + } + + return (0); +} + + +static struct cpufreq_driver acpi_cpufreq_driver = { + .verify = cpufreq_generic_frequency_table_verify, + .target_index = acpi_cpufreq_target, + .get = acpi_cpufreq_get, + .init = acpi_cpufreq_cpu_init, + .exit = acpi_cpufreq_cpu_exit, + .name = "acpi-cpufreq", + .attr = cpufreq_generic_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); +} + +late_initcall(acpi_cpufreq_init); +module_exit(acpi_cpufreq_exit); |