Robin Randhawa | 1f998b3 | 2015-06-29 18:01:58 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Obtain energy cost data from DT and populate relevant scheduler data |
| 3 | * structures. |
| 4 | * |
| 5 | * Copyright (C) 2015 ARM Ltd. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 18 | */ |
| 19 | #define pr_fmt(fmt) "sched-energy: " fmt |
| 20 | |
| 21 | #define DEBUG |
| 22 | |
| 23 | #include <linux/gfp.h> |
| 24 | #include <linux/of.h> |
| 25 | #include <linux/printk.h> |
| 26 | #include <linux/sched.h> |
| 27 | #include <linux/sched_energy.h> |
| 28 | #include <linux/stddef.h> |
| 29 | |
| 30 | struct sched_group_energy *sge_array[NR_CPUS][NR_SD_LEVELS]; |
| 31 | |
| 32 | static void free_resources(void) |
| 33 | { |
| 34 | int cpu, sd_level; |
| 35 | struct sched_group_energy *sge; |
| 36 | |
| 37 | for_each_possible_cpu(cpu) { |
| 38 | for_each_possible_sd_level(sd_level) { |
| 39 | sge = sge_array[cpu][sd_level]; |
| 40 | if (sge) { |
| 41 | kfree(sge->cap_states); |
| 42 | kfree(sge->idle_states); |
| 43 | kfree(sge); |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | } |
| 48 | |
| 49 | void init_sched_energy_costs(void) |
| 50 | { |
| 51 | struct device_node *cn, *cp; |
| 52 | struct capacity_state *cap_states; |
| 53 | struct idle_state *idle_states; |
| 54 | struct sched_group_energy *sge; |
| 55 | const struct property *prop; |
| 56 | int sd_level, i, nstates, cpu; |
| 57 | const __be32 *val; |
| 58 | |
| 59 | for_each_possible_cpu(cpu) { |
| 60 | cn = of_get_cpu_node(cpu, NULL); |
| 61 | if (!cn) { |
| 62 | pr_warn("CPU device node missing for CPU %d\n", cpu); |
| 63 | return; |
| 64 | } |
| 65 | |
| 66 | if (!of_find_property(cn, "sched-energy-costs", NULL)) { |
| 67 | pr_warn("CPU device node has no sched-energy-costs\n"); |
| 68 | return; |
| 69 | } |
| 70 | |
| 71 | for_each_possible_sd_level(sd_level) { |
| 72 | cp = of_parse_phandle(cn, "sched-energy-costs", sd_level); |
| 73 | if (!cp) |
| 74 | break; |
| 75 | |
| 76 | prop = of_find_property(cp, "busy-cost-data", NULL); |
| 77 | if (!prop || !prop->value) { |
| 78 | pr_warn("No busy-cost data, skipping sched_energy init\n"); |
| 79 | goto out; |
| 80 | } |
| 81 | |
| 82 | sge = kcalloc(1, sizeof(struct sched_group_energy), |
| 83 | GFP_NOWAIT); |
| 84 | |
| 85 | nstates = (prop->length / sizeof(u32)) / 2; |
| 86 | cap_states = kcalloc(nstates, |
| 87 | sizeof(struct capacity_state), |
| 88 | GFP_NOWAIT); |
| 89 | |
| 90 | for (i = 0, val = prop->value; i < nstates; i++) { |
| 91 | cap_states[i].cap = be32_to_cpup(val++); |
| 92 | cap_states[i].power = be32_to_cpup(val++); |
| 93 | } |
| 94 | |
| 95 | sge->nr_cap_states = nstates; |
| 96 | sge->cap_states = cap_states; |
| 97 | |
| 98 | prop = of_find_property(cp, "idle-cost-data", NULL); |
| 99 | if (!prop || !prop->value) { |
| 100 | pr_warn("No idle-cost data, skipping sched_energy init\n"); |
| 101 | goto out; |
| 102 | } |
| 103 | |
| 104 | nstates = (prop->length / sizeof(u32)); |
| 105 | idle_states = kcalloc(nstates, |
| 106 | sizeof(struct idle_state), |
| 107 | GFP_NOWAIT); |
| 108 | |
| 109 | for (i = 0, val = prop->value; i < nstates; i++) |
| 110 | idle_states[i].power = be32_to_cpup(val++); |
| 111 | |
| 112 | sge->nr_idle_states = nstates; |
| 113 | sge->idle_states = idle_states; |
| 114 | |
| 115 | sge_array[cpu][sd_level] = sge; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | pr_info("Sched-energy-costs installed from DT\n"); |
| 120 | return; |
| 121 | |
| 122 | out: |
| 123 | free_resources(); |
| 124 | } |