2 * Copyright (c) 2003-2005 Nate Lawson (SDG)
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/kernel.h>
34 #include <sys/sched.h>
37 #include <sys/power.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
43 #include <machine/bus.h>
44 #include <machine/resource.h>
47 #include <contrib/dev/acpica/include/acpi.h>
49 #include <dev/acpica/acpivar.h>
51 #include "cpufreq_if.h"
54 * Support for ACPI processor performance states (Px) according to
55 * section 8.3.3 of the ACPI 2.0c specification.
67 /* Offsets in struct cf_setting array for storing driver-specific values. */
68 #define PX_SPEC_CONTROL 0
69 #define PX_SPEC_STATUS 1
71 #define MAX_PX_STATES 16
73 struct acpi_perf_softc {
76 struct resource *perf_ctrl; /* Set new performance state. */
77 int perf_ctrl_type; /* Resource type for perf_ctrl. */
78 struct resource *perf_status; /* Check that transition succeeded. */
79 int perf_sts_type; /* Resource type for perf_status. */
80 struct acpi_px *px_states; /* ACPI perf states. */
81 uint32_t px_count; /* Total number of perf states. */
82 uint32_t px_max_avail; /* Lowest index state available. */
83 int px_curr_state; /* Active state index. */
85 int info_only; /* Can we set new states? */
88 #define PX_GET_REG(reg) \
89 (bus_space_read_4(rman_get_bustag((reg)), \
90 rman_get_bushandle((reg)), 0))
91 #define PX_SET_REG(reg, val) \
92 (bus_space_write_4(rman_get_bustag((reg)), \
93 rman_get_bushandle((reg)), 0, (val)))
95 #define ACPI_NOTIFY_PERF_STATES 0x80 /* _PSS changed. */
97 static void acpi_perf_identify(driver_t *driver, device_t parent);
98 static int acpi_perf_probe(device_t dev);
99 static int acpi_perf_attach(device_t dev);
100 static int acpi_perf_detach(device_t dev);
101 static int acpi_perf_evaluate(device_t dev);
102 static int acpi_px_to_set(device_t dev, struct acpi_px *px,
103 struct cf_setting *set);
104 static void acpi_px_available(struct acpi_perf_softc *sc);
105 static void acpi_px_startup(void *arg);
106 static void acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context);
107 static int acpi_px_settings(device_t dev, struct cf_setting *sets,
109 static int acpi_px_set(device_t dev, const struct cf_setting *set);
110 static int acpi_px_get(device_t dev, struct cf_setting *set);
111 static int acpi_px_type(device_t dev, int *type);
113 static device_method_t acpi_perf_methods[] = {
114 /* Device interface */
115 DEVMETHOD(device_identify, acpi_perf_identify),
116 DEVMETHOD(device_probe, acpi_perf_probe),
117 DEVMETHOD(device_attach, acpi_perf_attach),
118 DEVMETHOD(device_detach, acpi_perf_detach),
120 /* cpufreq interface */
121 DEVMETHOD(cpufreq_drv_set, acpi_px_set),
122 DEVMETHOD(cpufreq_drv_get, acpi_px_get),
123 DEVMETHOD(cpufreq_drv_type, acpi_px_type),
124 DEVMETHOD(cpufreq_drv_settings, acpi_px_settings),
129 static driver_t acpi_perf_driver = {
132 sizeof(struct acpi_perf_softc),
135 static devclass_t acpi_perf_devclass;
136 DRIVER_MODULE(acpi_perf, cpu, acpi_perf_driver, acpi_perf_devclass, 0, 0);
137 MODULE_DEPEND(acpi_perf, acpi, 1, 1, 1);
139 static MALLOC_DEFINE(M_ACPIPERF, "acpi_perf", "ACPI Performance states");
142 acpi_perf_identify(driver_t *driver, device_t parent)
147 /* Make sure we're not being doubly invoked. */
148 if (device_find_child(parent, "acpi_perf", -1) != NULL)
151 /* Get the handle for the Processor object and check for perf states. */
152 handle = acpi_get_handle(parent);
155 if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PSS", NULL, NULL)))
159 * Add a child to every CPU that has the right methods. In future
160 * versions of the ACPI spec, CPUs can have different settings.
161 * We probe this child now so that other devices that depend
162 * on it (i.e., for info about supported states) will see it.
164 if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_perf", -1)) != NULL)
165 device_probe_and_attach(dev);
167 device_printf(parent, "add acpi_perf child failed\n");
171 acpi_perf_probe(device_t dev)
175 struct resource *res;
177 int error, rid, type;
179 if (resource_disabled("acpi_perf", 0))
183 * Check the performance state registers. If they are of type
184 * "functional fixed hardware", we attach quietly since we will
185 * only be providing information on settings to other drivers.
188 handle = acpi_get_handle(dev);
190 buf.Length = ACPI_ALLOCATE_BUFFER;
191 if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PCT", NULL, &buf)))
193 pkg = (ACPI_OBJECT *)buf.Pointer;
194 if (ACPI_PKG_VALID(pkg, 2)) {
196 error = acpi_PkgGas(dev, pkg, 0, &type, &rid, &res, 0);
199 bus_release_resource(dev, type, rid, res);
200 bus_delete_resource(dev, type, rid);
201 device_set_desc(dev, "ACPI CPU Frequency Control");
209 AcpiOsFree(buf.Pointer);
215 acpi_perf_attach(device_t dev)
217 struct acpi_perf_softc *sc;
219 sc = device_get_softc(dev);
221 sc->handle = acpi_get_handle(dev);
222 sc->px_max_avail = 0;
223 sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
224 if (acpi_perf_evaluate(dev) != 0)
226 AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_px_startup, NULL);
228 cpufreq_register(dev);
234 acpi_perf_detach(device_t dev)
236 /* TODO: teardown registers, remove notify handler. */
240 /* Probe and setup any valid performance states (Px). */
242 acpi_perf_evaluate(device_t dev)
244 struct acpi_perf_softc *sc;
246 ACPI_OBJECT *pkg, *res;
248 int count, error, i, j;
252 /* Get the control values and parameters for each state. */
254 sc = device_get_softc(dev);
256 buf.Length = ACPI_ALLOCATE_BUFFER;
257 status = AcpiEvaluateObject(sc->handle, "_PSS", NULL, &buf);
258 if (ACPI_FAILURE(status))
261 pkg = (ACPI_OBJECT *)buf.Pointer;
262 if (!ACPI_PKG_VALID(pkg, 1)) {
263 device_printf(dev, "invalid top level _PSS package\n");
266 sc->px_count = pkg->Package.Count;
268 sc->px_states = malloc(sc->px_count * sizeof(struct acpi_px),
269 M_ACPIPERF, M_WAITOK | M_ZERO);
270 if (sc->px_states == NULL)
274 * Each state is a package of {CoreFreq, Power, TransitionLatency,
275 * BusMasterLatency, ControlVal, StatusVal}, sorted from highest
276 * performance to lowest.
279 for (i = 0; i < sc->px_count; i++) {
280 res = &pkg->Package.Elements[i];
281 if (!ACPI_PKG_VALID(res, 6)) {
284 device_printf(dev, "invalid _PSS package\n");
289 /* Parse the rest of the package into the struct. */
290 p = &sc->px_states[count].core_freq;
291 for (j = 0; j < 6; j++, p++)
292 acpi_PkgInt32(res, j, p);
295 * Check for some impossible frequencies that some systems
296 * use to indicate they don't actually support this Px state.
298 if (sc->px_states[count].core_freq == 0 ||
299 sc->px_states[count].core_freq == 9999 ||
300 sc->px_states[count].core_freq == 0x9999 ||
301 sc->px_states[count].core_freq >= 0xffff)
304 /* Check for duplicate entries */
306 sc->px_states[count - 1].core_freq ==
307 sc->px_states[count].core_freq)
312 sc->px_count = count;
314 /* No valid Px state found so give up. */
317 AcpiOsFree(buf.Pointer);
319 /* Get the control and status registers (one of each). */
321 buf.Length = ACPI_ALLOCATE_BUFFER;
322 status = AcpiEvaluateObject(sc->handle, "_PCT", NULL, &buf);
323 if (ACPI_FAILURE(status))
326 /* Check the package of two registers, each a Buffer in GAS format. */
327 pkg = (ACPI_OBJECT *)buf.Pointer;
328 if (!ACPI_PKG_VALID(pkg, 2)) {
329 device_printf(dev, "invalid perf register package\n");
333 error = acpi_PkgGas(sc->dev, pkg, 0, &sc->perf_ctrl_type, &sc->px_rid,
337 * If the register is of type FFixedHW, we can only return
338 * info, we can't get or set new settings.
340 if (error == EOPNOTSUPP) {
341 sc->info_only = TRUE;
344 device_printf(dev, "failed in PERF_CTL attach\n");
349 error = acpi_PkgGas(sc->dev, pkg, 1, &sc->perf_sts_type, &sc->px_rid,
350 &sc->perf_status, 0);
352 if (error == EOPNOTSUPP) {
353 sc->info_only = TRUE;
356 device_printf(dev, "failed in PERF_STATUS attach\n");
361 /* Get our current limit and register for notifies. */
362 acpi_px_available(sc);
363 AcpiInstallNotifyHandler(sc->handle, ACPI_DEVICE_NOTIFY,
370 free(sc->px_states, M_ACPIPERF);
371 sc->px_states = NULL;
374 bus_release_resource(sc->dev, sc->perf_ctrl_type, 0,
376 bus_delete_resource(sc->dev, sc->perf_ctrl_type, 0);
377 sc->perf_ctrl = NULL;
379 if (sc->perf_status) {
380 bus_release_resource(sc->dev, sc->perf_sts_type, 1,
382 bus_delete_resource(sc->dev, sc->perf_sts_type, 1);
383 sc->perf_status = NULL;
389 AcpiOsFree(buf.Pointer);
394 acpi_px_startup(void *arg)
397 /* Signal to the platform that we are taking over CPU control. */
398 if (AcpiGbl_FADT.PstateControl == 0)
401 AcpiOsWritePort(AcpiGbl_FADT.SmiCommand, AcpiGbl_FADT.PstateControl, 8);
406 acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context)
408 struct acpi_perf_softc *sc;
411 if (notify != ACPI_NOTIFY_PERF_STATES)
414 acpi_px_available(sc);
416 /* TODO: Implement notification when frequency changes. */
420 * Find the highest currently-supported performance state.
421 * This can be called at runtime (e.g., due to a docking event) at
422 * the request of a Notify on the processor object.
425 acpi_px_available(struct acpi_perf_softc *sc)
428 struct cf_setting set;
430 status = acpi_GetInteger(sc->handle, "_PPC", &sc->px_max_avail);
432 /* If the old state is too high, set current state to the new max. */
433 if (ACPI_SUCCESS(status)) {
434 if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN &&
435 sc->px_curr_state > sc->px_max_avail) {
436 acpi_px_to_set(sc->dev,
437 &sc->px_states[sc->px_max_avail], &set);
438 acpi_px_set(sc->dev, &set);
441 sc->px_max_avail = 0;
445 acpi_px_to_set(device_t dev, struct acpi_px *px, struct cf_setting *set)
448 if (px == NULL || set == NULL)
451 set->freq = px->core_freq;
452 set->power = px->power;
453 /* XXX Include BM latency too? */
454 set->lat = px->trans_lat;
455 set->volts = CPUFREQ_VAL_UNKNOWN;
457 set->spec[PX_SPEC_CONTROL] = px->ctrl_val;
458 set->spec[PX_SPEC_STATUS] = px->sts_val;
464 acpi_px_settings(device_t dev, struct cf_setting *sets, int *count)
466 struct acpi_perf_softc *sc;
469 sc = device_get_softc(dev);
470 if (sets == NULL || count == NULL)
472 if (*count < sc->px_count - sc->px_max_avail)
475 /* Return a list of settings that are currently valid. */
477 for (x = sc->px_max_avail; x < sc->px_count; x++, y++)
478 acpi_px_to_set(dev, &sc->px_states[x], &sets[y]);
479 *count = sc->px_count - sc->px_max_avail;
485 acpi_px_set(device_t dev, const struct cf_setting *set)
487 struct acpi_perf_softc *sc;
488 int i, status, sts_val, tries;
492 sc = device_get_softc(dev);
494 /* If we can't set new states, return immediately. */
498 /* Look up appropriate state, based on frequency. */
499 for (i = sc->px_max_avail; i < sc->px_count; i++) {
500 if (CPUFREQ_CMP(set->freq, sc->px_states[i].core_freq))
503 if (i == sc->px_count)
506 /* Write the appropriate value to the register. */
507 PX_SET_REG(sc->perf_ctrl, sc->px_states[i].ctrl_val);
510 * Try for up to 10 ms to verify the desired state was selected.
511 * This is longer than the standard says (1 ms) but in some modes,
512 * systems may take longer to respond.
514 sts_val = sc->px_states[i].sts_val;
515 for (tries = 0; tries < 1000; tries++) {
516 status = PX_GET_REG(sc->perf_status);
519 * If we match the status or the desired status is 8 bits
520 * and matches the relevant bits, assume we succeeded. It
521 * appears some systems (IBM R32) expect byte-wide access
522 * even though the standard says the register is 32-bit.
524 if (status == sts_val ||
525 ((sts_val & ~0xff) == 0 && (status & 0xff) == sts_val))
530 device_printf(dev, "Px transition to %d failed\n",
531 sc->px_states[i].core_freq);
534 sc->px_curr_state = i;
540 acpi_px_get(device_t dev, struct cf_setting *set)
542 struct acpi_perf_softc *sc;
549 sc = device_get_softc(dev);
551 /* If we can't get new states, return immediately. */
555 /* If we've set the rate before, use the cached value. */
556 if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN) {
557 acpi_px_to_set(dev, &sc->px_states[sc->px_curr_state], set);
561 /* Otherwise, estimate and try to match against our settings. */
562 pc = cpu_get_pcpu(dev);
565 cpu_est_clockrate(pc->pc_cpuid, &rate);
567 for (i = 0; i < sc->px_count; i++) {
568 if (CPUFREQ_CMP(sc->px_states[i].core_freq, rate)) {
569 sc->px_curr_state = i;
570 acpi_px_to_set(dev, &sc->px_states[i], set);
575 /* No match, give up. */
576 if (i == sc->px_count) {
577 sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
578 set->freq = CPUFREQ_VAL_UNKNOWN;
585 acpi_px_type(device_t dev, int *type)
587 struct acpi_perf_softc *sc;
591 sc = device_get_softc(dev);
593 *type = CPUFREQ_TYPE_ABSOLUTE;
595 *type |= CPUFREQ_FLAG_INFO_ONLY;