diff options
Diffstat (limited to 'drivers/cpufreq/vexpress_bL_cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/vexpress_bL_cpufreq.c | 282 |
1 files changed, 0 insertions, 282 deletions
diff --git a/drivers/cpufreq/vexpress_bL_cpufreq.c b/drivers/cpufreq/vexpress_bL_cpufreq.c deleted file mode 100644 index 5718bbecd984..000000000000 --- a/drivers/cpufreq/vexpress_bL_cpufreq.c +++ /dev/null @@ -1,282 +0,0 @@ -/* - * Vexpress big.LITTLE CPUFreq support - * Based on mach-integrator - * - * Copyright (C) 2012 ARM Ltd. - * Author: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> - * - * 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 "as is" WITHOUT ANY WARRANTY of any - * kind, whether express or implied; without even the implied warranty - * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ -#include <linux/cpufreq.h> -#include <linux/cpumask.h> -#include <linux/init.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/of_platform.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/smp.h> -#include <linux/spinlock.h> -#include <linux/sysfs.h> -#include <linux/types.h> - -#include <linux/vexpress.h> - -#define VEXPRESS_MAX_CLUSTER 2 - -static struct cpufreq_frequency_table *freq_table[VEXPRESS_MAX_CLUSTER]; -static atomic_t freq_table_users = ATOMIC_INIT(0); - -/* Cached current cluster for each CPU to save on IPIs */ -static DEFINE_PER_CPU(unsigned int, cpu_cur_cluster); - -/* - * Functions to get the current status. - * - * Beware that the cluster for another CPU may change unexpectedly. - */ - -static unsigned int get_local_cluster(void) -{ - unsigned int mpidr; - asm ("mrc\tp15, 0, %0, c0, c0, 5" : "=r" (mpidr)); - return (mpidr >> 8) & 0xf; -} - -static void __get_current_cluster(void *_data) -{ - unsigned int *_cluster = _data; - *_cluster = get_local_cluster(); -} - -static int get_current_cluster(unsigned int cpu) -{ - unsigned int cluster = 0; - smp_call_function_single(cpu, __get_current_cluster, &cluster, 1); - return cluster; -} - -static int get_current_cached_cluster(unsigned int cpu) -{ - return per_cpu(cpu_cur_cluster, cpu); -} - -/* Validate policy frequency range */ -static int vexpress_cpufreq_verify_policy(struct cpufreq_policy *policy) -{ - uint32_t cur_cluster = get_current_cached_cluster(policy->cpu); - - /* This call takes care of it all using freq_table */ - return cpufreq_frequency_table_verify(policy, freq_table[cur_cluster]); -} - -/* Set clock frequency */ -static int vexpress_cpufreq_set_target(struct cpufreq_policy *policy, - unsigned int target_freq, unsigned int relation) -{ - uint32_t cpu = policy->cpu; - struct cpufreq_freqs freqs; - uint32_t freq_tab_idx; - uint32_t cur_cluster; - int ret = 0; - - /* Read current clock rate */ - cur_cluster = get_current_cached_cluster(cpu); - - if (vexpress_spc_get_performance(cur_cluster, &freqs.old)) - return -EIO; - - /* Make sure that target_freq is within supported range */ - if (target_freq > policy->max) - target_freq = policy->max; - if (target_freq < policy->min) - target_freq = policy->min; - - /* Determine valid target frequency using freq_table */ - cpufreq_frequency_table_target(policy, freq_table[cur_cluster], - target_freq, relation, &freq_tab_idx); - freqs.new = freq_table[cur_cluster][freq_tab_idx].frequency; - - freqs.cpu = policy->cpu; - - if (freqs.old == freqs.new) - return 0; - - pr_debug("Requested Freq %d cpu %d\n", freqs.new, cpu); - - for_each_cpu(freqs.cpu, policy->cpus) - cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); - - ret = vexpress_spc_set_performance(cur_cluster, freqs.new); - if (ret) { - pr_err("Error %d while setting required OPP\n", ret); - return ret; - } - - policy->cur = freqs.new; - - for_each_cpu(freqs.cpu, policy->cpus) - cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); - - return ret; -} - -/* Get current clock frequency */ -static unsigned int vexpress_cpufreq_get(unsigned int cpu) -{ - uint32_t freq = 0; - uint32_t cur_cluster = get_current_cached_cluster(cpu); - - /* - * Read current clock rate with vexpress_spc call - */ - if (vexpress_spc_get_performance(cur_cluster, &freq)) - return -EIO; - - return freq; -} - -/* translate the integer array into cpufreq_frequency_table entries */ -static inline void _cpufreq_copy_table_from_array(uint32_t *table, - struct cpufreq_frequency_table *freq_table, int size) -{ - int i; - for (i = 0; i < size; i++) { - freq_table[i].index = i; - freq_table[i].frequency = table[i] / 1000; /* in kHZ */ - } - freq_table[i].index = size; - freq_table[i].frequency = CPUFREQ_TABLE_END; -} - -static int vexpress_cpufreq_of_init(void) -{ - uint32_t cpu_opp_num; - struct cpufreq_frequency_table *freqtable[VEXPRESS_MAX_CLUSTER]; - uint32_t *cpu_freqs; - int ret = 0, cluster_id = 0, len; - struct device_node *cluster = NULL; - const struct property *pp; - const u32 *hwid; - - while ((cluster = of_find_node_by_name(cluster, "cluster"))) { - hwid = of_get_property(cluster, "reg", &len); - if (hwid && len == 4) - cluster_id = be32_to_cpup(hwid); - - pp = of_find_property(cluster, "freqs", NULL); - if (!pp) - return -EINVAL; - cpu_opp_num = pp->length / sizeof(u32); - if (!cpu_opp_num) - return -ENODATA; - - cpu_freqs = kzalloc(sizeof(uint32_t) * cpu_opp_num, GFP_KERNEL); - freqtable[cluster_id] = - kzalloc(sizeof(struct cpufreq_frequency_table) * - (cpu_opp_num + 1), GFP_KERNEL); - if (!cpu_freqs || !freqtable[cluster_id]) { - ret = -ENOMEM; - goto free_mem; - } - of_property_read_u32_array(cluster, "freqs", - cpu_freqs, cpu_opp_num); - _cpufreq_copy_table_from_array(cpu_freqs, - freqtable[cluster_id], cpu_opp_num); - freq_table[cluster_id] = freqtable[cluster_id]; - - kfree(cpu_freqs); - } - return ret; -free_mem: - while (cluster_id >= 0) - kfree(freqtable[cluster_id--]); - kfree(cpu_freqs); - return ret; -} - -/* Per-CPU initialization */ -static int vexpress_cpufreq_init(struct cpufreq_policy *policy) -{ - int result = 0; - uint32_t cur_cluster = get_current_cluster(policy->cpu); - - if (atomic_inc_return(&freq_table_users) == 1) - result = vexpress_cpufreq_of_init(); - - if (freq_table[cur_cluster] == NULL) - result = -ENODATA; - - if (result) { - atomic_dec_return(&freq_table_users); - pr_err("CPUFreq - CPU %d failed to initialize\n", policy->cpu); - return result; - } - - result = - cpufreq_frequency_table_cpuinfo(policy, freq_table[cur_cluster]); - if (result) - return result; - - cpufreq_frequency_table_get_attr(freq_table[cur_cluster], policy->cpu); - - per_cpu(cpu_cur_cluster, policy->cpu) = cur_cluster; - - /* set default policy and cpuinfo */ - policy->min = policy->cpuinfo.min_freq; - policy->max = policy->cpuinfo.max_freq; - - policy->cpuinfo.transition_latency = 1000000; /* 1 ms assumed */ - policy->cur = vexpress_cpufreq_get(policy->cpu); - - cpumask_copy(policy->cpus, topology_core_cpumask(policy->cpu)); - cpumask_copy(policy->related_cpus, policy->cpus); - - pr_info("CPUFreq for CPU %d initialized\n", policy->cpu); - return result; -} - -/* Export freq_table to sysfs */ -static struct freq_attr *vexpress_cpufreq_attr[] = { - &cpufreq_freq_attr_scaling_available_freqs, - NULL, -}; - -static struct cpufreq_driver vexpress_cpufreq_driver = { - .flags = CPUFREQ_STICKY, - .verify = vexpress_cpufreq_verify_policy, - .target = vexpress_cpufreq_set_target, - .get = vexpress_cpufreq_get, - .init = vexpress_cpufreq_init, - .name = "vexpress-spc", - .attr = vexpress_cpufreq_attr, -}; - -static int __init vexpress_cpufreq_modinit(void) -{ - if (!vexpress_spc_check_loaded()) { - pr_info("vexpress cpufreq not initialised because no SPC found\n"); - return -ENODEV; - } - - return cpufreq_register_driver(&vexpress_cpufreq_driver); -} - -static void __exit vexpress_cpufreq_modexit(void) -{ - cpufreq_unregister_driver(&vexpress_cpufreq_driver); -} - -MODULE_DESCRIPTION("cpufreq driver for ARM vexpress big.LITTLE platform"); -MODULE_LICENSE("GPL"); - -module_init(vexpress_cpufreq_modinit); -module_exit(vexpress_cpufreq_modexit); |