| /* |
| * Copyright © 2013 Intel Corporation |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| * |
| */ |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <time.h> |
| #include <errno.h> |
| |
| #include "power.h" |
| #include "debugfs.h" |
| |
| /* XXX Is this exposed through RAPL? */ |
| |
| int power_init(struct power *power) |
| { |
| char buf[4096]; |
| int fd, len; |
| |
| memset(power, 0, sizeof(*power)); |
| |
| sprintf(buf, "%s/i915_energy_uJ", debugfs_path); |
| fd = open(buf, 0); |
| if (fd < 0) |
| return power->error = errno; |
| |
| len = read(fd, buf, sizeof(buf)); |
| close(fd); |
| |
| if (len < 0) |
| return power->error = errno; |
| |
| return 0; |
| } |
| |
| static uint64_t file_to_u64(const char *name) |
| { |
| char buf[4096]; |
| int fd, len; |
| |
| sprintf(buf, "%s/i915_energy_uJ", name); |
| fd = open(buf, 0); |
| if (fd < 0) |
| return 0; |
| |
| len = read(fd, buf, sizeof(buf)-1); |
| close(fd); |
| |
| if (len < 0) |
| return 0; |
| |
| buf[len] = '\0'; |
| |
| return strtoull(buf, 0, 0); |
| } |
| |
| static uint64_t clock_ms_to_u64(void) |
| { |
| struct timespec tv; |
| |
| if (clock_gettime(CLOCK_MONOTONIC, &tv) < 0) |
| return 0; |
| |
| return (uint64_t)tv.tv_sec * 1000 + tv.tv_nsec / 1000000; |
| } |
| |
| int power_update(struct power *power) |
| { |
| struct power_stat *s = &power->stat[power->count++&1]; |
| struct power_stat *d = &power->stat[power->count&1]; |
| uint64_t d_time; |
| |
| if (power->error) |
| return power->error; |
| |
| s->energy = file_to_u64("i915_energy_uJ"); |
| s->timestamp = clock_ms_to_u64(); |
| if (power->count == 1) |
| return EAGAIN; |
| |
| d_time = s->timestamp - d->timestamp; |
| if (d_time < 900) { /* HW sample rate seems to be stable ~1Hz */ |
| power->count--; |
| return power->count <= 1 ? EAGAIN : 0; |
| } |
| |
| power->power_mW = (s->energy - d->energy) / d_time; |
| power->new_sample = 1; |
| return 0; |
| } |