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),
128 static driver_t acpi_perf_driver = {
131 sizeof(struct acpi_perf_softc),
134 static devclass_t acpi_perf_devclass;
135 DRIVER_MODULE(acpi_perf, cpu, acpi_perf_driver, acpi_perf_devclass, 0, 0);
136 MODULE_DEPEND(acpi_perf, acpi, 1, 1, 1);
138 MALLOC_DEFINE(M_ACPIPERF, "acpi_perf", "ACPI Performance states");
141 acpi_perf_identify(driver_t *driver, device_t parent)
146 /* Make sure we're not being doubly invoked. */
147 if (device_find_child(parent, "acpi_perf", -1) != NULL)
150 /* Get the handle for the Processor object and check for perf states. */
151 handle = acpi_get_handle(parent);
154 if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PSS", NULL, NULL)))
158 * Add a child to every CPU that has the right methods. In future
159 * versions of the ACPI spec, CPUs can have different settings.
160 * We probe this child now so that other devices that depend
161 * on it (i.e., for info about supported states) will see it.
163 if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_perf", -1)) != NULL)
164 device_probe_and_attach(dev);
166 device_printf(parent, "add acpi_perf child failed\n");
170 acpi_perf_probe(device_t dev)
174 struct resource *res;
176 int error, rid, type;
178 if (resource_disabled("acpi_perf", 0))
182 * Check the performance state registers. If they are of type
183 * "functional fixed hardware", we attach quietly since we will
184 * only be providing information on settings to other drivers.
187 handle = acpi_get_handle(dev);
189 buf.Length = ACPI_ALLOCATE_BUFFER;
190 if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PCT", NULL, &buf)))
192 pkg = (ACPI_OBJECT *)buf.Pointer;
193 if (ACPI_PKG_VALID(pkg, 2)) {
195 error = acpi_PkgGas(dev, pkg, 0, &type, &rid, &res, 0);
198 bus_release_resource(dev, type, rid, res);
199 bus_delete_resource(dev, type, rid);
200 device_set_desc(dev, "ACPI CPU Frequency Control");
208 AcpiOsFree(buf.Pointer);
214 acpi_perf_attach(device_t dev)
216 struct acpi_perf_softc *sc;
218 sc = device_get_softc(dev);
220 sc->handle = acpi_get_handle(dev);
221 sc->px_max_avail = 0;
222 sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
223 if (acpi_perf_evaluate(dev) != 0)
225 AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_px_startup, NULL);
227 cpufreq_register(dev);
233 acpi_perf_detach(device_t dev)
235 /* TODO: teardown registers, remove notify handler. */
239 /* Probe and setup any valid performance states (Px). */
241 acpi_perf_evaluate(device_t dev)
243 struct acpi_perf_softc *sc;
245 ACPI_OBJECT *pkg, *res;
247 int count, error, i, j;
251 /* Get the control values and parameters for each state. */
253 sc = device_get_softc(dev);
255 buf.Length = ACPI_ALLOCATE_BUFFER;
256 status = AcpiEvaluateObject(sc->handle, "_PSS", NULL, &buf);
257 if (ACPI_FAILURE(status))
260 pkg = (ACPI_OBJECT *)buf.Pointer;
261 if (!ACPI_PKG_VALID(pkg, 1)) {
262 device_printf(dev, "invalid top level _PSS package\n");
265 sc->px_count = pkg->Package.Count;
267 sc->px_states = malloc(sc->px_count * sizeof(struct acpi_px),
268 M_ACPIPERF, M_WAITOK | M_ZERO);
269 if (sc->px_states == NULL)
273 * Each state is a package of {CoreFreq, Power, TransitionLatency,
274 * BusMasterLatency, ControlVal, StatusVal}, sorted from highest
275 * performance to lowest.
278 for (i = 0; i < sc->px_count; i++) {
279 res = &pkg->Package.Elements[i];
280 if (!ACPI_PKG_VALID(res, 6)) {
283 device_printf(dev, "invalid _PSS package\n");
288 /* Parse the rest of the package into the struct. */
289 p = &sc->px_states[count].core_freq;
290 for (j = 0; j < 6; j++, p++)
291 acpi_PkgInt32(res, j, p);
294 * Check for some impossible frequencies that some systems
295 * use to indicate they don't actually support this Px state.
297 if (sc->px_states[count].core_freq == 0 ||
298 sc->px_states[count].core_freq == 9999 ||
299 sc->px_states[count].core_freq == 0x9999 ||
300 sc->px_states[count].core_freq >= 0xffff)
303 /* Check for duplicate entries */
305 sc->px_states[count - 1].core_freq ==
306 sc->px_states[count].core_freq)
311 sc->px_count = count;
313 /* No valid Px state found so give up. */
316 AcpiOsFree(buf.Pointer);
318 /* Get the control and status registers (one of each). */
320 buf.Length = ACPI_ALLOCATE_BUFFER;
321 status = AcpiEvaluateObject(sc->handle, "_PCT", NULL, &buf);
322 if (ACPI_FAILURE(status))
325 /* Check the package of two registers, each a Buffer in GAS format. */
326 pkg = (ACPI_OBJECT *)buf.Pointer;
327 if (!ACPI_PKG_VALID(pkg, 2)) {
328 device_printf(dev, "invalid perf register package\n");
332 error = acpi_PkgGas(sc->dev, pkg, 0, &sc->perf_ctrl_type, &sc->px_rid,
336 * If the register is of type FFixedHW, we can only return
337 * info, we can't get or set new settings.
339 if (error == EOPNOTSUPP) {
340 sc->info_only = TRUE;
343 device_printf(dev, "failed in PERF_CTL attach\n");
348 error = acpi_PkgGas(sc->dev, pkg, 1, &sc->perf_sts_type, &sc->px_rid,
349 &sc->perf_status, 0);
351 if (error == EOPNOTSUPP) {
352 sc->info_only = TRUE;
355 device_printf(dev, "failed in PERF_STATUS attach\n");
360 /* Get our current limit and register for notifies. */
361 acpi_px_available(sc);
362 AcpiInstallNotifyHandler(sc->handle, ACPI_DEVICE_NOTIFY,
369 free(sc->px_states, M_ACPIPERF);
370 sc->px_states = NULL;
373 bus_release_resource(sc->dev, sc->perf_ctrl_type, 0,
375 bus_delete_resource(sc->dev, sc->perf_ctrl_type, 0);
376 sc->perf_ctrl = NULL;
378 if (sc->perf_status) {
379 bus_release_resource(sc->dev, sc->perf_sts_type, 1,
381 bus_delete_resource(sc->dev, sc->perf_sts_type, 1);
382 sc->perf_status = NULL;
388 AcpiOsFree(buf.Pointer);
393 acpi_px_startup(void *arg)
396 /* Signal to the platform that we are taking over CPU control. */
397 if (AcpiGbl_FADT.PstateControl == 0)
400 AcpiOsWritePort(AcpiGbl_FADT.SmiCommand, AcpiGbl_FADT.PstateControl, 8);
405 acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context)
407 struct acpi_perf_softc *sc;
410 if (notify != ACPI_NOTIFY_PERF_STATES)
413 acpi_px_available(sc);
415 /* TODO: Implement notification when frequency changes. */
419 * Find the highest currently-supported performance state.
420 * This can be called at runtime (e.g., due to a docking event) at
421 * the request of a Notify on the processor object.
424 acpi_px_available(struct acpi_perf_softc *sc)
427 struct cf_setting set;
429 status = acpi_GetInteger(sc->handle, "_PPC", &sc->px_max_avail);
431 /* If the old state is too high, set current state to the new max. */
432 if (ACPI_SUCCESS(status)) {
433 if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN &&
434 sc->px_curr_state > sc->px_max_avail) {
435 acpi_px_to_set(sc->dev,
436 &sc->px_states[sc->px_max_avail], &set);
437 acpi_px_set(sc->dev, &set);
440 sc->px_max_avail = 0;
444 acpi_px_to_set(device_t dev, struct acpi_px *px, struct cf_setting *set)
447 if (px == NULL || set == NULL)
450 set->freq = px->core_freq;
451 set->power = px->power;
452 /* XXX Include BM latency too? */
453 set->lat = px->trans_lat;
454 set->volts = CPUFREQ_VAL_UNKNOWN;
456 set->spec[PX_SPEC_CONTROL] = px->ctrl_val;
457 set->spec[PX_SPEC_STATUS] = px->sts_val;
463 acpi_px_settings(device_t dev, struct cf_setting *sets, int *count)
465 struct acpi_perf_softc *sc;
468 sc = device_get_softc(dev);
469 if (sets == NULL || count == NULL)
471 if (*count < sc->px_count - sc->px_max_avail)
474 /* Return a list of settings that are currently valid. */
476 for (x = sc->px_max_avail; x < sc->px_count; x++, y++)
477 acpi_px_to_set(dev, &sc->px_states[x], &sets[y]);
478 *count = sc->px_count - sc->px_max_avail;
484 acpi_px_set(device_t dev, const struct cf_setting *set)
486 struct acpi_perf_softc *sc;
487 int i, status, sts_val, tries;
491 sc = device_get_softc(dev);
493 /* If we can't set new states, return immediately. */
497 /* Look up appropriate state, based on frequency. */
498 for (i = sc->px_max_avail; i < sc->px_count; i++) {
499 if (CPUFREQ_CMP(set->freq, sc->px_states[i].core_freq))
502 if (i == sc->px_count)
505 /* Write the appropriate value to the register. */
506 PX_SET_REG(sc->perf_ctrl, sc->px_states[i].ctrl_val);
509 * Try for up to 10 ms to verify the desired state was selected.
510 * This is longer than the standard says (1 ms) but in some modes,
511 * systems may take longer to respond.
513 sts_val = sc->px_states[i].sts_val;
514 for (tries = 0; tries < 1000; tries++) {
515 status = PX_GET_REG(sc->perf_status);
518 * If we match the status or the desired status is 8 bits
519 * and matches the relevant bits, assume we succeeded. It
520 * appears some systems (IBM R32) expect byte-wide access
521 * even though the standard says the register is 32-bit.
523 if (status == sts_val ||
524 ((sts_val & ~0xff) == 0 && (status & 0xff) == sts_val))
529 device_printf(dev, "Px transition to %d failed\n",
530 sc->px_states[i].core_freq);
533 sc->px_curr_state = i;
539 acpi_px_get(device_t dev, struct cf_setting *set)
541 struct acpi_perf_softc *sc;
548 sc = device_get_softc(dev);
550 /* If we can't get new states, return immediately. */
554 /* If we've set the rate before, use the cached value. */
555 if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN) {
556 acpi_px_to_set(dev, &sc->px_states[sc->px_curr_state], set);
560 /* Otherwise, estimate and try to match against our settings. */
561 pc = cpu_get_pcpu(dev);
564 cpu_est_clockrate(pc->pc_cpuid, &rate);
566 for (i = 0; i < sc->px_count; i++) {
567 if (CPUFREQ_CMP(sc->px_states[i].core_freq, rate)) {
568 sc->px_curr_state = i;
569 acpi_px_to_set(dev, &sc->px_states[i], set);
574 /* No match, give up. */
575 if (i == sc->px_count) {
576 sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
577 set->freq = CPUFREQ_VAL_UNKNOWN;
584 acpi_px_type(device_t dev, int *type)
586 struct acpi_perf_softc *sc;
590 sc = device_get_softc(dev);
592 *type = CPUFREQ_TYPE_ABSOLUTE;
594 *type |= CPUFREQ_FLAG_INFO_ONLY;