diff options
author | Vic Yang <victoryang@chromium.org> | 2013-08-05 11:17:35 +0800 |
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committer | chrome-internal-fetch <chrome-internal-fetch@google.com> | 2013-08-27 23:20:33 +0000 |
commit | 5d014fd2dd5e92ad35a4f2dd1b58e0b1baebb65e (patch) | |
tree | 2078f9831177392f22ba202cbea4b09d69a9a710 /chip/lm4/fan.c | |
parent | 99f06c39aabd262653c96c589c5cd26fc1fb8389 (diff) | |
download | chrome-ec-5d014fd2dd5e92ad35a4f2dd1b58e0b1baebb65e.tar.gz |
Refactor PWM module
This unifies the PWM module interface for LM4 and STM32. Now PWM
channels are defined in board.h/board.c. Instead of calling functions
named pwm_set_fan_duty(x), one can now use pwm_set_duty(PWM_CH_FAN, x),
which prevents additional functions added when we have a new PWM
channel.
BUG=chrome-os-partner:18343
TEST=Limit input current on Spring.
TEST=Check power LED in S0/S3/S5 on Snow.
TEST=Check keyboard backlight functionality on Link.
TEST=Check fan speed control/detecting on Link.
BRANCH=None
Change-Id: Ibac4d79f72e65c94776d503558a7592f7db859dc
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/64450
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Diffstat (limited to 'chip/lm4/fan.c')
-rw-r--r-- | chip/lm4/fan.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/chip/lm4/fan.c b/chip/lm4/fan.c new file mode 100644 index 0000000000..cf109573ff --- /dev/null +++ b/chip/lm4/fan.c @@ -0,0 +1,411 @@ +/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +/* PWM control module for Chromebook fans */ + +#include "clock.h" +#include "common.h" +#include "console.h" +#include "fan.h" +#include "gpio.h" +#include "hooks.h" +#include "host_command.h" +#include "pwm.h" +#include "registers.h" +#include "system.h" +#include "task.h" +#include "timer.h" +#include "util.h" + +/*****************************************************************************/ +/* Chip-specific stuff */ + +/* Maximum RPM for fan controller */ +#define MAX_RPM 0x1fff +/* Max PWM for fan controller */ +#define MAX_PWM 0x1ff +/* + * Scaling factor for requested/actual RPM for CPU fan. We need this because + * the fan controller on Blizzard filters tach pulses that are less than 64 + * 15625Hz ticks apart, which works out to ~7000rpm on an unscaled fan. By + * telling the controller we actually have twice as many edges per revolution, + * the controller can handle fans that actually go twice as fast. See + * crosbug.com/p/7718. + */ +#define CPU_FAN_SCALE 2 + +static int fan_get_enabled(void) +{ + return pwm_get_enabled(PWM_CH_FAN); +} + +static void fan_set_enabled(int enable) +{ + pwm_enable(PWM_CH_FAN, enable); + +#ifdef CONFIG_PWM_FAN_EN_GPIO + gpio_set_level(CONFIG_PWM_FAN_EN_GPIO, enable); +#endif /* CONFIG_PWM_FAN_EN_GPIO */ +} + +static int fan_get_rpm_mode(void) +{ + return (LM4_FAN_FANCH(FAN_CH_CPU) & 0x0001) ? 0 : 1; +} + +static void fan_set_rpm_mode(int rpm_mode) +{ + int was_enabled = fan_get_enabled(); + int was_rpm = fan_get_rpm_mode(); + + if (!was_rpm && rpm_mode) { + /* Enable RPM control */ + fan_set_enabled(0); + LM4_FAN_FANCH(FAN_CH_CPU) &= ~0x0001; + fan_set_enabled(was_enabled); + } else if (was_rpm && !rpm_mode) { + /* Disable RPM mode */ + fan_set_enabled(0); + LM4_FAN_FANCH(FAN_CH_CPU) |= 0x0001; + fan_set_enabled(was_enabled); + } +} + +static int fan_get_rpm_actual(void) +{ + return (LM4_FAN_FANCST(FAN_CH_CPU) & MAX_RPM) * CPU_FAN_SCALE; +} + +static int fan_get_rpm_target(void) +{ + return (LM4_FAN_FANCMD(FAN_CH_CPU) & MAX_RPM) * CPU_FAN_SCALE; +} + +static void fan_set_rpm_target(int rpm) +{ + /* Apply fan scaling */ + if (rpm > 0) + rpm /= CPU_FAN_SCALE; + + /* Treat out-of-range requests as requests for maximum fan speed */ + if (rpm < 0 || rpm > MAX_RPM) + rpm = MAX_RPM; + + LM4_FAN_FANCMD(FAN_CH_CPU) = rpm; +} + +static int fan_get_status(void) +{ + return (LM4_FAN_FANSTS >> (2 * FAN_CH_CPU)) & 0x03; +} +static const char * const human_status[] = { + "not spinning", "changing", "locked", "frustrated" +}; + +/** + * Return non-zero if fan is enabled but stalled. + */ +static int fan_is_stalled(void) +{ + /* Must be enabled with non-zero target to stall */ + if (!fan_get_enabled() || fan_get_rpm_target() == 0) + return 0; + + /* Check for stall condition */ + return (((LM4_FAN_FANSTS >> (2 * FAN_CH_CPU)) & 0x03) == 0) ? 1 : 0; +} + +/*****************************************************************************/ +/* Control functions */ + +/* True if we're listening to the thermal control task. False if we're setting + * things manually. */ +static int thermal_control_enabled; + +static void fan_set_thermal_control_enabled(int enable) +{ + thermal_control_enabled = enable; + + /* If controlling the fan, need it in RPM-control mode */ + if (enable) + fan_set_rpm_mode(1); +} + +/* The thermal task will only call this function with pct in [0,100]. */ +void pwm_fan_set_percent_needed(int pct) +{ + int rpm; + + if (!thermal_control_enabled) + return; + + rpm = pwm_fan_percent_to_rpm(pct); + + fan_set_rpm_target(rpm); +} + +static void fan_set_duty_cycle(int percent) +{ + /* Move the fan to manual control */ + fan_set_rpm_mode(0); + + /* Always enable the fan */ + fan_set_enabled(1); + + /* Disable thermal engine automatic fan control. */ + fan_set_thermal_control_enabled(0); + + /* Set the duty cycle */ + pwm_set_duty(PWM_CH_FAN, percent); +} + +static int fan_get_duty_cycle(void) +{ + return pwm_get_duty(PWM_CH_FAN); +} + +/*****************************************************************************/ +/* Console commands */ + +static int cc_fanauto(int argc, char **argv) +{ + fan_set_thermal_control_enabled(1); + return EC_SUCCESS; +} +DECLARE_CONSOLE_COMMAND(fanauto, cc_fanauto, + NULL, + "Enable thermal fan control", + NULL); + + +static int cc_faninfo(int argc, char **argv) +{ + int tmp; + ccprintf("Actual: %4d rpm\n", fan_get_rpm_actual()); + ccprintf("Target: %4d rpm\n", fan_get_rpm_target()); + ccprintf("Duty: %d%%\n", fan_get_duty_cycle()); + tmp = fan_get_status(); + ccprintf("Status: %d (%s)\n", tmp, human_status[tmp]); + ccprintf("Mode: %s\n", fan_get_rpm_mode() ? "rpm" : "duty"); + ccprintf("Auto: %s\n", thermal_control_enabled ? "yes" : "no"); + ccprintf("Enable: %s\n", fan_get_enabled() ? "yes" : "no"); +#ifdef CONFIG_PWM_FAN_POWER_GOOD + ccprintf("Power: %s\n", +#ifdef CONFIG_PWM_FAN_EN_GPIO + gpio_get_level(CONFIG_PWM_FAN_EN_GPIO) && +#endif + gpio_get_level(CONFIG_PWM_FAN_POWER_GOOD) ? "yes" : "no"); +#endif + + + return EC_SUCCESS; +} +DECLARE_CONSOLE_COMMAND(faninfo, cc_faninfo, + NULL, + "Print fan info", + NULL); + +static int cc_fanset(int argc, char **argv) +{ + int rpm; + char *e; + + if (argc < 2) + return EC_ERROR_PARAM_COUNT; + + rpm = strtoi(argv[1], &e, 0); + if (*e == '%') { /* Wait, that's a percentage */ + ccprintf("Fan rpm given as %d%%\n", rpm); + if (rpm < 0) + rpm = 0; + else if (rpm > 100) + rpm = 100; + rpm = pwm_fan_percent_to_rpm(rpm); + } else if (*e) { + return EC_ERROR_PARAM1; + } + + /* Move the fan to automatic control */ + fan_set_rpm_mode(1); + + /* Always enable the fan */ + fan_set_enabled(1); + + /* Disable thermal engine automatic fan control. */ + fan_set_thermal_control_enabled(0); + + fan_set_rpm_target(rpm); + + ccprintf("Setting fan rpm target to %d\n", rpm); + + return EC_SUCCESS; +} +DECLARE_CONSOLE_COMMAND(fanset, cc_fanset, + "rpm | pct%", + "Set fan speed", + NULL); + +static int cc_fanduty(int argc, char **argv) +{ + int percent = 0; + char *e; + + if (argc < 2) + return EC_ERROR_PARAM_COUNT; + + percent = strtoi(argv[1], &e, 0); + if (*e) + return EC_ERROR_PARAM1; + + ccprintf("Setting fan duty cycle to %d%%\n", percent); + fan_set_duty_cycle(percent); + + return EC_SUCCESS; +} +DECLARE_CONSOLE_COMMAND(fanduty, cc_fanduty, + "percent", + "Set fan duty cycle", + NULL); + +/*****************************************************************************/ +/* Host commands */ + +static int hc_pwm_get_fan_target_rpm(struct host_cmd_handler_args *args) +{ + struct ec_response_pwm_get_fan_rpm *r = args->response; + + r->rpm = fan_get_rpm_target(); + args->response_size = sizeof(*r); + + return EC_RES_SUCCESS; +} +DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_FAN_TARGET_RPM, + hc_pwm_get_fan_target_rpm, + EC_VER_MASK(0)); + +static int hc_pwm_set_fan_target_rpm(struct host_cmd_handler_args *args) +{ + const struct ec_params_pwm_set_fan_target_rpm *p = args->params; + + fan_set_thermal_control_enabled(0); + fan_set_rpm_mode(1); + fan_set_rpm_target(p->rpm); + + return EC_RES_SUCCESS; +} +DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_TARGET_RPM, + hc_pwm_set_fan_target_rpm, + EC_VER_MASK(0)); + +static int hc_pwm_set_fan_duty(struct host_cmd_handler_args *args) +{ + const struct ec_params_pwm_set_fan_duty *p = args->params; + fan_set_duty_cycle(p->percent); + + return EC_RES_SUCCESS; +} +DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_FAN_DUTY, + hc_pwm_set_fan_duty, + EC_VER_MASK(0)); + +static int hc_thermal_auto_fan_ctrl(struct host_cmd_handler_args *args) +{ + fan_set_thermal_control_enabled(1); + return EC_RES_SUCCESS; +} +DECLARE_HOST_COMMAND(EC_CMD_THERMAL_AUTO_FAN_CTRL, + hc_thermal_auto_fan_ctrl, + EC_VER_MASK(0)); + + +/*****************************************************************************/ +/* Hooks */ + +#define PWMFAN_SYSJUMP_TAG 0x5046 /* "PF" */ +#define PWM_HOOK_VERSION 1 +/* Saved PWM state across sysjumps */ +struct pwm_fan_state { + uint16_t fan_rpm; + uint8_t fan_en; + char pad; /* Pad to multiple of 4 bytes. */ +}; + +static void pwm_fan_init(void) +{ + const struct pwm_fan_state *prev; + uint16_t *mapped; + int version, size; + int i; + + gpio_config_module(MODULE_PWM_FAN, 1); + + prev = (const struct pwm_fan_state *) + system_get_jump_tag(PWMFAN_SYSJUMP_TAG, &version, &size); + if (prev && version == PWM_HOOK_VERSION && size == sizeof(*prev)) { + /* Restore previous state. */ + fan_set_enabled(prev->fan_en); + fan_set_rpm_target(prev->fan_rpm); + } else { + /* Set initial fan speed to maximum */ + pwm_fan_set_percent_needed(100); + } + + fan_set_thermal_control_enabled(1); + + /* Initialize memory-mapped data */ + mapped = (uint16_t *)host_get_memmap(EC_MEMMAP_FAN); + for (i = 0; i < EC_FAN_SPEED_ENTRIES; i++) + mapped[i] = EC_FAN_SPEED_NOT_PRESENT; +} +DECLARE_HOOK(HOOK_INIT, pwm_fan_init, HOOK_PRIO_DEFAULT + 1); + +static void pwm_fan_second(void) +{ + uint16_t *mapped = (uint16_t *)host_get_memmap(EC_MEMMAP_FAN); + + if (fan_is_stalled()) { + mapped[0] = EC_FAN_SPEED_STALLED; + /* + * Issue warning. As we have thermal shutdown + * protection, issuing warning here should be enough. + */ + host_set_single_event(EC_HOST_EVENT_THERMAL); + cprintf(CC_PWM, "[%T Fan stalled!]\n"); + } else { + mapped[0] = fan_get_rpm_actual(); + } +} +DECLARE_HOOK(HOOK_SECOND, pwm_fan_second, HOOK_PRIO_DEFAULT); + +static void pwm_fan_preserve_state(void) +{ + struct pwm_fan_state state; + + state.fan_en = fan_get_enabled(); + state.fan_rpm = fan_get_rpm_target(); + + system_add_jump_tag(PWMFAN_SYSJUMP_TAG, PWM_HOOK_VERSION, + sizeof(state), &state); +} +DECLARE_HOOK(HOOK_SYSJUMP, pwm_fan_preserve_state, HOOK_PRIO_DEFAULT); + +static void pwm_fan_resume(void) +{ + fan_set_enabled(1); +} +DECLARE_HOOK(HOOK_CHIPSET_RESUME, pwm_fan_resume, HOOK_PRIO_DEFAULT); + +static void pwm_fan_S3_S5(void) +{ + /* Take back fan control when the processor shuts down */ + fan_set_thermal_control_enabled(1); + /* For now don't do anything with it. We'll have to turn it on again if + * we need active cooling during heavy battery charging or something. + */ + fan_set_rpm_target(0); + fan_set_enabled(0); /* crosbug.com/p/8097 */ +} +DECLARE_HOOK(HOOK_CHIPSET_SUSPEND, pwm_fan_S3_S5, HOOK_PRIO_DEFAULT); +DECLARE_HOOK(HOOK_CHIPSET_SHUTDOWN, pwm_fan_S3_S5, HOOK_PRIO_DEFAULT); |