diff options
Diffstat (limited to 'sys/dev/acpica/acpi_cpu.c')
| -rw-r--r-- | sys/dev/acpica/acpi_cpu.c | 414 |
1 files changed, 414 insertions, 0 deletions
diff --git a/sys/dev/acpica/acpi_cpu.c b/sys/dev/acpica/acpi_cpu.c new file mode 100644 index 0000000..30c1cfe --- /dev/null +++ b/sys/dev/acpica/acpi_cpu.c @@ -0,0 +1,414 @@ +/*- + * Copyright (c) 2001 Michael Smith + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include "opt_acpi.h" +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/bus.h> +#include <sys/power.h> + +#include <machine/bus_pio.h> +#include <machine/bus.h> +#include <machine/resource.h> +#include <sys/rman.h> + +#include "acpi.h" + +#include <dev/acpica/acpivar.h> + +/* + * Support for ACPI Processor devices. + * + * Note that this only provides ACPI 1.0 support (with the exception of the + * PSTATE_CNT field). 2.0 support will involve implementing _PTC, _PCT, + * _PSS and _PPC. + */ + +/* + * Hooks for the ACPI CA debugging infrastructure + */ +#define _COMPONENT ACPI_PROCESSOR +ACPI_MODULE_NAME("PROCESSOR") + +struct acpi_cpu_softc { + device_t cpu_dev; + ACPI_HANDLE cpu_handle; + + u_int32_t cpu_id; + + /* CPU throttling control register */ + struct resource *cpu_p_blk; +#define CPU_GET_P_CNT(sc) (bus_space_read_4(rman_get_bustag((sc)->cpu_p_blk), \ + rman_get_bushandle((sc)->cpu_p_blk), \ + 0)) +#define CPU_SET_P_CNT(sc, val) (bus_space_write_4(rman_get_bustag((sc)->cpu_p_blk), \ + rman_get_bushandle((sc)->cpu_p_blk), \ + 0, (val))) +#define CPU_P_CNT_THT_EN (1<<4) +}; + +/* + * Speeds are stored in counts, from 1 - CPU_MAX_SPEED, and + * reported to the user in tenths of a percent. + */ +static u_int32_t cpu_duty_offset; +static u_int32_t cpu_duty_width; +#define CPU_MAX_SPEED (1 << cpu_duty_width) +#define CPU_SPEED_PERCENT(x) ((1000 * (x)) / CPU_MAX_SPEED) +#define CPU_SPEED_PRINTABLE(x) (CPU_SPEED_PERCENT(x) / 10),(CPU_SPEED_PERCENT(x) % 10) + +static u_int32_t cpu_smi_cmd; /* should be a generic way to do this */ +static u_int8_t cpu_pstate_cnt; + +static u_int32_t cpu_current_state; +static u_int32_t cpu_performance_state; +static u_int32_t cpu_economy_state; +static u_int32_t cpu_max_state; + +static device_t *cpu_devices; +static int cpu_ndevices; + +static struct sysctl_ctx_list acpi_cpu_sysctl_ctx; +static struct sysctl_oid *acpi_cpu_sysctl_tree; + +static int acpi_cpu_probe(device_t dev); +static int acpi_cpu_attach(device_t dev); +static void acpi_cpu_init_throttling(void *arg); +static void acpi_cpu_set_speed(u_int32_t speed); +static void acpi_cpu_power_profile(void *arg); +static int acpi_cpu_speed_sysctl(SYSCTL_HANDLER_ARGS); + +static device_method_t acpi_cpu_methods[] = { + /* Device interface */ + DEVMETHOD(device_probe, acpi_cpu_probe), + DEVMETHOD(device_attach, acpi_cpu_attach), + + {0, 0} +}; + +static driver_t acpi_cpu_driver = { + "acpi_cpu", + acpi_cpu_methods, + sizeof(struct acpi_cpu_softc), +}; + +static devclass_t acpi_cpu_devclass; +DRIVER_MODULE(acpi_cpu, acpi, acpi_cpu_driver, acpi_cpu_devclass, 0, 0); + +static int +acpi_cpu_probe(device_t dev) +{ + if (!acpi_disabled("cpu") && + (acpi_get_type(dev) == ACPI_TYPE_PROCESSOR)) { + device_set_desc(dev, "CPU"); /* XXX get more verbose description? */ + return(0); + } + return(ENXIO); +} + +static int +acpi_cpu_attach(device_t dev) +{ + struct acpi_cpu_softc *sc; + struct acpi_softc *acpi_sc; + ACPI_OBJECT processor; + ACPI_BUFFER buf; + ACPI_STATUS status; + u_int32_t p_blk; + u_int32_t p_blk_length; + u_int32_t duty_end; + int rid; + + ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); + + ACPI_ASSERTLOCK; + + sc = device_get_softc(dev); + sc->cpu_dev = dev; + sc->cpu_handle = acpi_get_handle(dev); + + /* + * Get global parameters from the FADT. + */ + if (device_get_unit(sc->cpu_dev) == 0) { + cpu_duty_offset = AcpiGbl_FADT->DutyOffset; + cpu_duty_width = AcpiGbl_FADT->DutyWidth; + cpu_smi_cmd = AcpiGbl_FADT->SmiCmd; + cpu_pstate_cnt = AcpiGbl_FADT->PstateCnt; + + /* validate the offset/width */ + if (cpu_duty_width > 0) { + duty_end = cpu_duty_offset + cpu_duty_width - 1; + /* check that it fits */ + if (duty_end > 31) { + printf("acpi_cpu: CLK_VAL field overflows P_CNT register\n"); + cpu_duty_width = 0; + } + /* check for overlap with the THT_EN bit */ + if ((cpu_duty_offset <= 4) && (duty_end >= 4)) { + printf("acpi_cpu: CLK_VAL field overlaps THT_EN bit\n"); + cpu_duty_width = 0; + } + } + + /* + * Start the throttling process once the probe phase completes, if we think that + * it's going to be useful. If the duty width value is zero, there are no significant + * bits in the register and thus no throttled states. + */ + if (cpu_duty_width > 0) { + AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cpu_init_throttling, NULL); + + acpi_sc = acpi_device_get_parent_softc(dev); + sysctl_ctx_init(&acpi_cpu_sysctl_ctx); + acpi_cpu_sysctl_tree = SYSCTL_ADD_NODE(&acpi_cpu_sysctl_ctx, + SYSCTL_CHILDREN(acpi_sc->acpi_sysctl_tree), + OID_AUTO, "cpu", CTLFLAG_RD, 0, ""); + + SYSCTL_ADD_INT(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), + OID_AUTO, "max_speed", CTLFLAG_RD, + &cpu_max_state, 0, "maximum CPU speed"); + SYSCTL_ADD_INT(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), + OID_AUTO, "current_speed", CTLFLAG_RD, + &cpu_current_state, 0, "current CPU speed"); + SYSCTL_ADD_PROC(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), + OID_AUTO, "performance_speed", CTLTYPE_INT | CTLFLAG_RW, + &cpu_performance_state, 0, acpi_cpu_speed_sysctl, "I", ""); + SYSCTL_ADD_PROC(&acpi_cpu_sysctl_ctx, SYSCTL_CHILDREN(acpi_cpu_sysctl_tree), + OID_AUTO, "economy_speed", CTLTYPE_INT | CTLFLAG_RW, + &cpu_economy_state, 0, acpi_cpu_speed_sysctl, "I", ""); + } + } + + /* + * Get the processor object. + */ + buf.Pointer = &processor; + buf.Length = sizeof(processor); + if (ACPI_FAILURE(status = AcpiEvaluateObject(sc->cpu_handle, NULL, NULL, &buf))) { + device_printf(sc->cpu_dev, "couldn't get Processor object - %s\n", AcpiFormatException(status)); + return_VALUE(ENXIO); + } + if (processor.Type != ACPI_TYPE_PROCESSOR) { + device_printf(sc->cpu_dev, "Processor object has bad type %d\n", processor.Type); + return_VALUE(ENXIO); + } + sc->cpu_id = processor.Processor.ProcId; + + /* + * If it looks like we support throttling, find this CPU's P_BLK. + * + * Note that some systems seem to duplicate the P_BLK pointer across + * multiple CPUs, so not getting the resource is not fatal. + * + * XXX should support _PTC here as well, once we work out how to parse it. + * + * XXX is it valid to assume that the P_BLK must be 6 bytes long? + */ + if (cpu_duty_width > 0) { + p_blk = processor.Processor.PblkAddress; + p_blk_length = processor.Processor.PblkLength; + + /* allocate bus space if possible */ + if ((p_blk > 0) && (p_blk_length == 6)) { + rid = 0; + bus_set_resource(sc->cpu_dev, SYS_RES_IOPORT, rid, p_blk, p_blk_length); + sc->cpu_p_blk = bus_alloc_resource(sc->cpu_dev, SYS_RES_IOPORT, &rid, 0, ~0, 1, + RF_ACTIVE); + + ACPI_DEBUG_PRINT((ACPI_DB_IO, "acpi_cpu%d: throttling with P_BLK at 0x%x/%d%s\n", + device_get_unit(sc->cpu_dev), p_blk, p_blk_length, + sc->cpu_p_blk ? "" : " (shadowed)")); + } + } + return_VALUE(0); +} + +/* + * Call this *after* all CPUs have been attached. + * + * Takes the ACPI lock to avoid fighting anyone over the SMI command + * port. Could probably lock less code. + */ +static void +acpi_cpu_init_throttling(void *arg) +{ + int cpu_temp_speed; + ACPI_LOCK_DECL; + + ACPI_LOCK; + + /* get set of CPU devices */ + devclass_get_devices(acpi_cpu_devclass, &cpu_devices, &cpu_ndevices); + + /* initialise throttling states */ + cpu_max_state = CPU_MAX_SPEED; + cpu_performance_state = cpu_max_state; + cpu_economy_state = cpu_performance_state / 2; + if (cpu_economy_state == 0) /* 0 is 'reserved' */ + cpu_economy_state++; + if (TUNABLE_INT_FETCH("hw.acpi.cpu.performance_speed", + &cpu_temp_speed) && cpu_temp_speed > 0 && + cpu_temp_speed <= cpu_max_state) + cpu_performance_state = cpu_temp_speed; + if (TUNABLE_INT_FETCH("hw.acpi.cpu.economy_speed", + &cpu_temp_speed) && cpu_temp_speed > 0 && + cpu_temp_speed <= cpu_max_state) + cpu_economy_state = cpu_temp_speed; + + /* register performance profile change handler */ + EVENTHANDLER_REGISTER(power_profile_change, acpi_cpu_power_profile, NULL, 0); + + /* if ACPI 2.0+, signal platform that we are taking over throttling */ + if (cpu_pstate_cnt != 0) { + /* XXX should be a generic interface for this */ + AcpiOsWritePort(cpu_smi_cmd, cpu_pstate_cnt, 8); + } + + ACPI_UNLOCK; + + /* set initial speed */ + acpi_cpu_power_profile(NULL); + + printf("acpi_cpu: CPU throttling enabled, %d steps from 100%% to %d.%d%%\n", + CPU_MAX_SPEED, CPU_SPEED_PRINTABLE(1)); +} + +/* + * Set CPUs to the new state. + * + * Must be called with the ACPI lock held. + */ +static void +acpi_cpu_set_speed(u_int32_t speed) +{ + struct acpi_cpu_softc *sc; + int i; + u_int32_t p_cnt, clk_val; + + ACPI_ASSERTLOCK; + + /* iterate over processors */ + for (i = 0; i < cpu_ndevices; i++) { + sc = device_get_softc(cpu_devices[i]); + if (sc->cpu_p_blk == NULL) + continue; + + /* get the current P_CNT value and disable throttling */ + p_cnt = CPU_GET_P_CNT(sc); + p_cnt &= ~CPU_P_CNT_THT_EN; + CPU_SET_P_CNT(sc, p_cnt); + + /* if we're at maximum speed, that's all */ + if (speed < CPU_MAX_SPEED) { + + /* mask the old CLK_VAL off and or-in the new value */ + clk_val = CPU_MAX_SPEED << cpu_duty_offset; + p_cnt &= ~clk_val; + p_cnt |= (speed << cpu_duty_offset); + + /* write the new P_CNT value and then enable throttling */ + CPU_SET_P_CNT(sc, p_cnt); + p_cnt |= CPU_P_CNT_THT_EN; + CPU_SET_P_CNT(sc, p_cnt); + } + ACPI_VPRINT(sc->cpu_dev, acpi_device_get_parent_softc(sc->cpu_dev), + "set speed to %d.%d%%\n", CPU_SPEED_PRINTABLE(speed)); + } + cpu_current_state = speed; +} + +/* + * Power profile change hook. + * + * Uses the ACPI lock to avoid reentrancy. + */ +static void +acpi_cpu_power_profile(void *arg) +{ + int state; + u_int32_t new; + ACPI_LOCK_DECL; + + state = power_profile_get_state(); + if (state != POWER_PROFILE_PERFORMANCE && + state != POWER_PROFILE_ECONOMY) { + return; + } + + ACPI_LOCK; + + switch (state) { + case POWER_PROFILE_PERFORMANCE: + new = cpu_performance_state; + break; + case POWER_PROFILE_ECONOMY: + new = cpu_economy_state; + break; + default: + new = cpu_current_state; + break; + } + + if (cpu_current_state != new) + acpi_cpu_set_speed(new); + + ACPI_UNLOCK; +} + +/* + * Handle changes in the performance/ecomony CPU settings. + * + * Does not need the ACPI lock (although setting *argp should + * probably be atomic). + */ +static int +acpi_cpu_speed_sysctl(SYSCTL_HANDLER_ARGS) +{ + u_int32_t *argp; + u_int32_t arg; + int error; + + argp = (u_int32_t *)oidp->oid_arg1; + arg = *argp; + error = sysctl_handle_int(oidp, &arg, 0, req); + + /* error or no new value */ + if ((error != 0) || (req->newptr == NULL)) + return(error); + + /* range check */ + if ((arg < 1) || (arg > cpu_max_state)) + return(EINVAL); + + /* set new value and possibly switch */ + *argp = arg; + acpi_cpu_power_profile(NULL); + + return(0); +} |
