1/*-
2 * Copyright (c) 2003-2005 Nate Lawson (SDG)
3 * Copyright (c) 2001 Michael Smith
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include "opt_acpi.h"
32#include <sys/param.h>
33#include <sys/bus.h>
34#include <sys/cpu.h>
35#include <sys/kernel.h>
36#include <sys/malloc.h>
37#include <sys/module.h>
38#include <sys/pcpu.h>
39#include <sys/power.h>
40#include <sys/proc.h>
41#include <sys/sched.h>
42#include <sys/sbuf.h>
43#include <sys/smp.h>
44
45#include <dev/pci/pcivar.h>
46#include <machine/atomic.h>
47#include <machine/bus.h>
48#if defined(__amd64__) || defined(__i386__)
49#include <machine/clock.h>
50#include <machine/specialreg.h>
51#include <machine/md_var.h>
52#endif
53#include <sys/rman.h>
54
55#include <contrib/dev/acpica/include/acpi.h>
56#include <contrib/dev/acpica/include/accommon.h>
57
58#include <dev/acpica/acpivar.h>
59
60/*
61 * Support for ACPI Processor devices, including C[1-3] sleep states.
62 */
63
64/* Hooks for the ACPI CA debugging infrastructure */
65#define _COMPONENT	ACPI_PROCESSOR
66ACPI_MODULE_NAME("PROCESSOR")
67
68struct acpi_cx {
69    struct resource	*p_lvlx;	/* Register to read to enter state. */
70    uint32_t		 type;		/* C1-3 (C4 and up treated as C3). */
71    uint32_t		 trans_lat;	/* Transition latency (usec). */
72    uint32_t		 power;		/* Power consumed (mW). */
73    int			 res_type;	/* Resource type for p_lvlx. */
74    int			 res_rid;	/* Resource ID for p_lvlx. */
75    bool		 do_mwait;
76    uint32_t		 mwait_hint;
77    bool		 mwait_hw_coord;
78    bool		 mwait_bm_avoidance;
79};
80#define MAX_CX_STATES	 8
81
82struct acpi_cpu_softc {
83    device_t		 cpu_dev;
84    ACPI_HANDLE		 cpu_handle;
85    struct pcpu		*cpu_pcpu;
86    uint32_t		 cpu_acpi_id;	/* ACPI processor id */
87    uint32_t		 cpu_p_blk;	/* ACPI P_BLK location */
88    uint32_t		 cpu_p_blk_len;	/* P_BLK length (must be 6). */
89    struct acpi_cx	 cpu_cx_states[MAX_CX_STATES];
90    int			 cpu_cx_count;	/* Number of valid Cx states. */
91    int			 cpu_prev_sleep;/* Last idle sleep duration. */
92    int			 cpu_features;	/* Child driver supported features. */
93    /* Runtime state. */
94    int			 cpu_non_c2;	/* Index of lowest non-C2 state. */
95    int			 cpu_non_c3;	/* Index of lowest non-C3 state. */
96    u_int		 cpu_cx_stats[MAX_CX_STATES];/* Cx usage history. */
97    /* Values for sysctl. */
98    struct sysctl_ctx_list cpu_sysctl_ctx;
99    struct sysctl_oid	*cpu_sysctl_tree;
100    int			 cpu_cx_lowest;
101    int			 cpu_cx_lowest_lim;
102    int			 cpu_disable_idle; /* Disable entry to idle function */
103    char 		 cpu_cx_supported[64];
104};
105
106struct acpi_cpu_device {
107    struct resource_list	ad_rl;
108};
109
110#define CPU_GET_REG(reg, width) 					\
111    (bus_space_read_ ## width(rman_get_bustag((reg)), 			\
112		      rman_get_bushandle((reg)), 0))
113#define CPU_SET_REG(reg, width, val)					\
114    (bus_space_write_ ## width(rman_get_bustag((reg)), 			\
115		       rman_get_bushandle((reg)), 0, (val)))
116
117#define ACPI_NOTIFY_CX_STATES	0x81	/* _CST changed. */
118
119#define CPU_QUIRK_NO_C3		(1<<0)	/* C3-type states are not usable. */
120#define CPU_QUIRK_NO_BM_CTRL	(1<<2)	/* No bus mastering control. */
121
122#define PCI_VENDOR_INTEL	0x8086
123#define PCI_DEVICE_82371AB_3	0x7113	/* PIIX4 chipset for quirks. */
124#define PCI_REVISION_A_STEP	0
125#define PCI_REVISION_B_STEP	1
126#define PCI_REVISION_4E		2
127#define PCI_REVISION_4M		3
128#define PIIX4_DEVACTB_REG	0x58
129#define PIIX4_BRLD_EN_IRQ0	(1<<0)
130#define PIIX4_BRLD_EN_IRQ	(1<<1)
131#define PIIX4_BRLD_EN_IRQ8	(1<<5)
132#define PIIX4_STOP_BREAK_MASK	(PIIX4_BRLD_EN_IRQ0 | PIIX4_BRLD_EN_IRQ | PIIX4_BRLD_EN_IRQ8)
133#define PIIX4_PCNTRL_BST_EN	(1<<10)
134
135#define	CST_FFH_VENDOR_INTEL	1
136#define	CST_FFH_INTEL_CL_C1IO	1
137#define	CST_FFH_INTEL_CL_MWAIT	2
138#define	CST_FFH_MWAIT_HW_COORD	0x0001
139#define	CST_FFH_MWAIT_BM_AVOID	0x0002
140
141#define	CPUDEV_DEVICE_ID	"ACPI0007"
142
143/* Allow users to ignore processor orders in MADT. */
144static int cpu_unordered;
145SYSCTL_INT(_debug_acpi, OID_AUTO, cpu_unordered, CTLFLAG_RDTUN,
146    &cpu_unordered, 0,
147    "Do not use the MADT to match ACPI Processor objects to CPUs.");
148
149/* Knob to disable acpi_cpu devices */
150bool acpi_cpu_disabled = false;
151
152/* Platform hardware resource information. */
153static uint32_t		 cpu_smi_cmd;	/* Value to write to SMI_CMD. */
154static uint8_t		 cpu_cst_cnt;	/* Indicate we are _CST aware. */
155static int		 cpu_quirks;	/* Indicate any hardware bugs. */
156
157/* Values for sysctl. */
158static struct sysctl_ctx_list cpu_sysctl_ctx;
159static struct sysctl_oid *cpu_sysctl_tree;
160static int		 cpu_cx_generic;
161static int		 cpu_cx_lowest_lim;
162
163static device_t		*cpu_devices;
164static int		 cpu_ndevices;
165static struct acpi_cpu_softc **cpu_softc;
166ACPI_SERIAL_DECL(cpu, "ACPI CPU");
167
168static int	acpi_cpu_probe(device_t dev);
169static int	acpi_cpu_attach(device_t dev);
170static int	acpi_cpu_suspend(device_t dev);
171static int	acpi_cpu_resume(device_t dev);
172static int	acpi_pcpu_get_id(device_t dev, uint32_t *acpi_id,
173		    uint32_t *cpu_id);
174static struct resource_list *acpi_cpu_get_rlist(device_t dev, device_t child);
175static device_t	acpi_cpu_add_child(device_t dev, u_int order, const char *name,
176		    int unit);
177static int	acpi_cpu_read_ivar(device_t dev, device_t child, int index,
178		    uintptr_t *result);
179static int	acpi_cpu_shutdown(device_t dev);
180static void	acpi_cpu_cx_probe(struct acpi_cpu_softc *sc);
181static void	acpi_cpu_generic_cx_probe(struct acpi_cpu_softc *sc);
182static int	acpi_cpu_cx_cst(struct acpi_cpu_softc *sc);
183static void	acpi_cpu_startup(void *arg);
184static void	acpi_cpu_startup_cx(struct acpi_cpu_softc *sc);
185static void	acpi_cpu_cx_list(struct acpi_cpu_softc *sc);
186#if defined(__i386__) || defined(__amd64__)
187static void	acpi_cpu_idle(sbintime_t sbt);
188#endif
189static void	acpi_cpu_notify(ACPI_HANDLE h, UINT32 notify, void *context);
190static void	acpi_cpu_quirks(void);
191static void	acpi_cpu_quirks_piix4(void);
192static int	acpi_cpu_usage_sysctl(SYSCTL_HANDLER_ARGS);
193static int	acpi_cpu_usage_counters_sysctl(SYSCTL_HANDLER_ARGS);
194static int	acpi_cpu_set_cx_lowest(struct acpi_cpu_softc *sc);
195static int	acpi_cpu_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS);
196static int	acpi_cpu_global_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS);
197#if defined(__i386__) || defined(__amd64__)
198static int	acpi_cpu_method_sysctl(SYSCTL_HANDLER_ARGS);
199#endif
200
201static device_method_t acpi_cpu_methods[] = {
202    /* Device interface */
203    DEVMETHOD(device_probe,	acpi_cpu_probe),
204    DEVMETHOD(device_attach,	acpi_cpu_attach),
205    DEVMETHOD(device_detach,	bus_generic_detach),
206    DEVMETHOD(device_shutdown,	acpi_cpu_shutdown),
207    DEVMETHOD(device_suspend,	acpi_cpu_suspend),
208    DEVMETHOD(device_resume,	acpi_cpu_resume),
209
210    /* Bus interface */
211    DEVMETHOD(bus_add_child,	acpi_cpu_add_child),
212    DEVMETHOD(bus_read_ivar,	acpi_cpu_read_ivar),
213    DEVMETHOD(bus_get_resource_list, acpi_cpu_get_rlist),
214    DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
215    DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
216    DEVMETHOD(bus_alloc_resource, bus_generic_rl_alloc_resource),
217    DEVMETHOD(bus_release_resource, bus_generic_rl_release_resource),
218    DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
219    DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
220    DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
221    DEVMETHOD(bus_teardown_intr, bus_generic_teardown_intr),
222
223    DEVMETHOD_END
224};
225
226static driver_t acpi_cpu_driver = {
227    "cpu",
228    acpi_cpu_methods,
229    sizeof(struct acpi_cpu_softc),
230};
231
232static devclass_t acpi_cpu_devclass;
233DRIVER_MODULE(cpu, acpi, acpi_cpu_driver, acpi_cpu_devclass, 0, 0);
234MODULE_DEPEND(cpu, acpi, 1, 1, 1);
235
236static int
237acpi_cpu_probe(device_t dev)
238{
239    static char		   *cpudev_ids[] = { CPUDEV_DEVICE_ID, NULL };
240    int			   acpi_id, cpu_id;
241    ACPI_BUFFER		   buf;
242    ACPI_HANDLE		   handle;
243    ACPI_OBJECT		   *obj;
244    ACPI_STATUS		   status;
245    ACPI_OBJECT_TYPE	   type;
246
247    if (acpi_disabled("cpu") || acpi_cpu_disabled)
248	return (ENXIO);
249    type = acpi_get_type(dev);
250    if (type != ACPI_TYPE_PROCESSOR && type != ACPI_TYPE_DEVICE)
251	return (ENXIO);
252    if (type == ACPI_TYPE_DEVICE &&
253	ACPI_ID_PROBE(device_get_parent(dev), dev, cpudev_ids) == NULL)
254	return (ENXIO);
255
256    handle = acpi_get_handle(dev);
257    if (cpu_softc == NULL)
258	cpu_softc = malloc(sizeof(struct acpi_cpu_softc *) *
259	    (mp_maxid + 1), M_TEMP /* XXX */, M_WAITOK | M_ZERO);
260
261    if (type == ACPI_TYPE_PROCESSOR) {
262	/* Get our Processor object. */
263	buf.Pointer = NULL;
264	buf.Length = ACPI_ALLOCATE_BUFFER;
265	status = AcpiEvaluateObject(handle, NULL, NULL, &buf);
266	if (ACPI_FAILURE(status)) {
267	    device_printf(dev, "probe failed to get Processor obj - %s\n",
268		AcpiFormatException(status));
269	    return (ENXIO);
270	}
271	obj = (ACPI_OBJECT *)buf.Pointer;
272	if (obj->Type != ACPI_TYPE_PROCESSOR) {
273	    device_printf(dev, "Processor object has bad type %d\n",
274		obj->Type);
275	    AcpiOsFree(obj);
276	    return (ENXIO);
277	}
278
279	/*
280	 * Find the processor associated with our unit.  We could use the
281	 * ProcId as a key, however, some boxes do not have the same values
282	 * in their Processor object as the ProcId values in the MADT.
283	 */
284	acpi_id = obj->Processor.ProcId;
285	AcpiOsFree(obj);
286    } else {
287	status = acpi_GetInteger(handle, "_UID", &acpi_id);
288	if (ACPI_FAILURE(status)) {
289	    device_printf(dev, "Device object has bad value - %s\n",
290		AcpiFormatException(status));
291	    return (ENXIO);
292	}
293    }
294    if (acpi_pcpu_get_id(dev, &acpi_id, &cpu_id) != 0)
295	return (ENXIO);
296
297    /*
298     * Check if we already probed this processor.  We scan the bus twice
299     * so it's possible we've already seen this one.
300     */
301    if (cpu_softc[cpu_id] != NULL)
302	return (ENXIO);
303
304    /* Mark this processor as in-use and save our derived id for attach. */
305    cpu_softc[cpu_id] = (void *)1;
306    acpi_set_private(dev, (void*)(intptr_t)cpu_id);
307    device_set_desc(dev, "ACPI CPU");
308
309    if (!bootverbose && device_get_unit(dev) != 0) {
310	    device_quiet(dev);
311	    device_quiet_children(dev);
312    }
313
314    return (0);
315}
316
317static int
318acpi_cpu_attach(device_t dev)
319{
320    ACPI_BUFFER		   buf;
321    ACPI_OBJECT		   arg, *obj;
322    ACPI_OBJECT_LIST	   arglist;
323    struct pcpu		   *pcpu_data;
324    struct acpi_cpu_softc *sc;
325    struct acpi_softc	  *acpi_sc;
326    ACPI_STATUS		   status;
327    u_int		   features;
328    int			   cpu_id, drv_count, i;
329    driver_t 		  **drivers;
330    uint32_t		   cap_set[3];
331
332    /* UUID needed by _OSC evaluation */
333    static uint8_t cpu_oscuuid[16] = { 0x16, 0xA6, 0x77, 0x40, 0x0C, 0x29,
334				       0xBE, 0x47, 0x9E, 0xBD, 0xD8, 0x70,
335				       0x58, 0x71, 0x39, 0x53 };
336
337    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
338
339    sc = device_get_softc(dev);
340    sc->cpu_dev = dev;
341    sc->cpu_handle = acpi_get_handle(dev);
342    cpu_id = (int)(intptr_t)acpi_get_private(dev);
343    cpu_softc[cpu_id] = sc;
344    pcpu_data = pcpu_find(cpu_id);
345    pcpu_data->pc_device = dev;
346    sc->cpu_pcpu = pcpu_data;
347    cpu_smi_cmd = AcpiGbl_FADT.SmiCommand;
348    cpu_cst_cnt = AcpiGbl_FADT.CstControl;
349
350    if (acpi_get_type(dev) == ACPI_TYPE_PROCESSOR) {
351	buf.Pointer = NULL;
352	buf.Length = ACPI_ALLOCATE_BUFFER;
353	status = AcpiEvaluateObject(sc->cpu_handle, NULL, NULL, &buf);
354	if (ACPI_FAILURE(status)) {
355	    device_printf(dev, "attach failed to get Processor obj - %s\n",
356		AcpiFormatException(status));
357	    return (ENXIO);
358	}
359	obj = (ACPI_OBJECT *)buf.Pointer;
360	sc->cpu_p_blk = obj->Processor.PblkAddress;
361	sc->cpu_p_blk_len = obj->Processor.PblkLength;
362	sc->cpu_acpi_id = obj->Processor.ProcId;
363	AcpiOsFree(obj);
364    } else {
365	KASSERT(acpi_get_type(dev) == ACPI_TYPE_DEVICE,
366	    ("Unexpected ACPI object"));
367	status = acpi_GetInteger(sc->cpu_handle, "_UID", &sc->cpu_acpi_id);
368	if (ACPI_FAILURE(status)) {
369	    device_printf(dev, "Device object has bad value - %s\n",
370		AcpiFormatException(status));
371	    return (ENXIO);
372	}
373	sc->cpu_p_blk = 0;
374	sc->cpu_p_blk_len = 0;
375    }
376    ACPI_DEBUG_PRINT((ACPI_DB_INFO, "acpi_cpu%d: P_BLK at %#x/%d\n",
377		     device_get_unit(dev), sc->cpu_p_blk, sc->cpu_p_blk_len));
378
379    /*
380     * If this is the first cpu we attach, create and initialize the generic
381     * resources that will be used by all acpi cpu devices.
382     */
383    if (device_get_unit(dev) == 0) {
384	/* Assume we won't be using generic Cx mode by default */
385	cpu_cx_generic = FALSE;
386
387	/* Install hw.acpi.cpu sysctl tree */
388	acpi_sc = acpi_device_get_parent_softc(dev);
389	sysctl_ctx_init(&cpu_sysctl_ctx);
390	cpu_sysctl_tree = SYSCTL_ADD_NODE(&cpu_sysctl_ctx,
391	    SYSCTL_CHILDREN(acpi_sc->acpi_sysctl_tree), OID_AUTO, "cpu",
392	    CTLFLAG_RD, 0, "node for CPU children");
393    }
394
395    /*
396     * Before calling any CPU methods, collect child driver feature hints
397     * and notify ACPI of them.  We support unified SMP power control
398     * so advertise this ourselves.  Note this is not the same as independent
399     * SMP control where each CPU can have different settings.
400     */
401    sc->cpu_features = ACPI_CAP_SMP_SAME | ACPI_CAP_SMP_SAME_C3 |
402      ACPI_CAP_C1_IO_HALT;
403
404#if defined(__i386__) || defined(__amd64__)
405    /*
406     * Ask for MWAIT modes if not disabled and interrupts work
407     * reasonable with MWAIT.
408     */
409    if (!acpi_disabled("mwait") && cpu_mwait_usable())
410	sc->cpu_features |= ACPI_CAP_SMP_C1_NATIVE | ACPI_CAP_SMP_C3_NATIVE;
411#endif
412
413    if (devclass_get_drivers(acpi_cpu_devclass, &drivers, &drv_count) == 0) {
414	for (i = 0; i < drv_count; i++) {
415	    if (ACPI_GET_FEATURES(drivers[i], &features) == 0)
416		sc->cpu_features |= features;
417	}
418	free(drivers, M_TEMP);
419    }
420
421    /*
422     * CPU capabilities are specified in
423     * Intel Processor Vendor-Specific ACPI Interface Specification.
424     */
425    if (sc->cpu_features) {
426	cap_set[1] = sc->cpu_features;
427	status = acpi_EvaluateOSC(sc->cpu_handle, cpu_oscuuid, 1, 2, cap_set,
428	    cap_set, false);
429	if (ACPI_SUCCESS(status)) {
430	    if (cap_set[0] != 0)
431		device_printf(dev, "_OSC returned status %#x\n", cap_set[0]);
432	}
433	else {
434	    arglist.Pointer = &arg;
435	    arglist.Count = 1;
436	    arg.Type = ACPI_TYPE_BUFFER;
437	    arg.Buffer.Length = sizeof(cap_set);
438	    arg.Buffer.Pointer = (uint8_t *)cap_set;
439	    cap_set[0] = 1; /* revision */
440	    cap_set[1] = 1; /* number of capabilities integers */
441	    cap_set[2] = sc->cpu_features;
442	    AcpiEvaluateObject(sc->cpu_handle, "_PDC", &arglist, NULL);
443	}
444    }
445
446    /* Probe for Cx state support. */
447    acpi_cpu_cx_probe(sc);
448
449    return (0);
450}
451
452static void
453acpi_cpu_postattach(void *unused __unused)
454{
455    device_t *devices;
456    int err;
457    int i, n;
458    int attached;
459
460    err = devclass_get_devices(acpi_cpu_devclass, &devices, &n);
461    if (err != 0) {
462	printf("devclass_get_devices(acpi_cpu_devclass) failed\n");
463	return;
464    }
465    attached = 0;
466    for (i = 0; i < n; i++)
467	if (device_is_attached(devices[i]) &&
468	    device_get_driver(devices[i]) == &acpi_cpu_driver)
469	    attached = 1;
470    for (i = 0; i < n; i++)
471	bus_generic_probe(devices[i]);
472    for (i = 0; i < n; i++)
473	bus_generic_attach(devices[i]);
474    free(devices, M_TEMP);
475
476    if (attached) {
477#ifdef EARLY_AP_STARTUP
478	acpi_cpu_startup(NULL);
479#else
480	/* Queue post cpu-probing task handler */
481	AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_cpu_startup, NULL);
482#endif
483    }
484}
485
486SYSINIT(acpi_cpu, SI_SUB_CONFIGURE, SI_ORDER_MIDDLE,
487    acpi_cpu_postattach, NULL);
488
489static void
490disable_idle(struct acpi_cpu_softc *sc)
491{
492    cpuset_t cpuset;
493
494    CPU_SETOF(sc->cpu_pcpu->pc_cpuid, &cpuset);
495    sc->cpu_disable_idle = TRUE;
496
497    /*
498     * Ensure that the CPU is not in idle state or in acpi_cpu_idle().
499     * Note that this code depends on the fact that the rendezvous IPI
500     * can not penetrate context where interrupts are disabled and acpi_cpu_idle
501     * is called and executed in such a context with interrupts being re-enabled
502     * right before return.
503     */
504    smp_rendezvous_cpus(cpuset, smp_no_rendezvous_barrier, NULL,
505	smp_no_rendezvous_barrier, NULL);
506}
507
508static void
509enable_idle(struct acpi_cpu_softc *sc)
510{
511
512    sc->cpu_disable_idle = FALSE;
513}
514
515#if defined(__i386__) || defined(__amd64__)
516static int
517is_idle_disabled(struct acpi_cpu_softc *sc)
518{
519
520    return (sc->cpu_disable_idle);
521}
522#endif
523
524/*
525 * Disable any entry to the idle function during suspend and re-enable it
526 * during resume.
527 */
528static int
529acpi_cpu_suspend(device_t dev)
530{
531    int error;
532
533    error = bus_generic_suspend(dev);
534    if (error)
535	return (error);
536    disable_idle(device_get_softc(dev));
537    return (0);
538}
539
540static int
541acpi_cpu_resume(device_t dev)
542{
543
544    enable_idle(device_get_softc(dev));
545    return (bus_generic_resume(dev));
546}
547
548/*
549 * Find the processor associated with a given ACPI ID.  By default,
550 * use the MADT to map ACPI IDs to APIC IDs and use that to locate a
551 * processor.  Some systems have inconsistent ASL and MADT however.
552 * For these systems the cpu_unordered tunable can be set in which
553 * case we assume that Processor objects are listed in the same order
554 * in both the MADT and ASL.
555 */
556static int
557acpi_pcpu_get_id(device_t dev, uint32_t *acpi_id, uint32_t *cpu_id)
558{
559    struct pcpu	*pc;
560    uint32_t	 i, idx;
561
562    KASSERT(acpi_id != NULL, ("Null acpi_id"));
563    KASSERT(cpu_id != NULL, ("Null cpu_id"));
564    idx = device_get_unit(dev);
565
566    /*
567     * If pc_acpi_id for CPU 0 is not initialized (e.g. a non-APIC
568     * UP box) use the ACPI ID from the first processor we find.
569     */
570    if (idx == 0 && mp_ncpus == 1) {
571	pc = pcpu_find(0);
572	if (pc->pc_acpi_id == 0xffffffff)
573	    pc->pc_acpi_id = *acpi_id;
574	*cpu_id = 0;
575	return (0);
576    }
577
578    CPU_FOREACH(i) {
579	pc = pcpu_find(i);
580	KASSERT(pc != NULL, ("no pcpu data for %d", i));
581	if (cpu_unordered) {
582	    if (idx-- == 0) {
583		/*
584		 * If pc_acpi_id doesn't match the ACPI ID from the
585		 * ASL, prefer the MADT-derived value.
586		 */
587		if (pc->pc_acpi_id != *acpi_id)
588		    *acpi_id = pc->pc_acpi_id;
589		*cpu_id = pc->pc_cpuid;
590		return (0);
591	    }
592	} else {
593	    if (pc->pc_acpi_id == *acpi_id) {
594		if (bootverbose)
595		    device_printf(dev,
596			"Processor %s (ACPI ID %u) -> APIC ID %d\n",
597			acpi_name(acpi_get_handle(dev)), *acpi_id,
598			pc->pc_cpuid);
599		*cpu_id = pc->pc_cpuid;
600		return (0);
601	    }
602	}
603    }
604
605    if (bootverbose)
606	printf("ACPI: Processor %s (ACPI ID %u) ignored\n",
607	    acpi_name(acpi_get_handle(dev)), *acpi_id);
608
609    return (ESRCH);
610}
611
612static struct resource_list *
613acpi_cpu_get_rlist(device_t dev, device_t child)
614{
615    struct acpi_cpu_device *ad;
616
617    ad = device_get_ivars(child);
618    if (ad == NULL)
619	return (NULL);
620    return (&ad->ad_rl);
621}
622
623static device_t
624acpi_cpu_add_child(device_t dev, u_int order, const char *name, int unit)
625{
626    struct acpi_cpu_device *ad;
627    device_t child;
628
629    if ((ad = malloc(sizeof(*ad), M_TEMP, M_NOWAIT | M_ZERO)) == NULL)
630	return (NULL);
631
632    resource_list_init(&ad->ad_rl);
633
634    child = device_add_child_ordered(dev, order, name, unit);
635    if (child != NULL)
636	device_set_ivars(child, ad);
637    else
638	free(ad, M_TEMP);
639    return (child);
640}
641
642static int
643acpi_cpu_read_ivar(device_t dev, device_t child, int index, uintptr_t *result)
644{
645    struct acpi_cpu_softc *sc;
646
647    sc = device_get_softc(dev);
648    switch (index) {
649    case ACPI_IVAR_HANDLE:
650	*result = (uintptr_t)sc->cpu_handle;
651	break;
652    case CPU_IVAR_PCPU:
653	*result = (uintptr_t)sc->cpu_pcpu;
654	break;
655#if defined(__amd64__) || defined(__i386__)
656    case CPU_IVAR_NOMINAL_MHZ:
657	if (tsc_is_invariant) {
658	    *result = (uintptr_t)(atomic_load_acq_64(&tsc_freq) / 1000000);
659	    break;
660	}
661	/* FALLTHROUGH */
662#endif
663    default:
664	return (ENOENT);
665    }
666    return (0);
667}
668
669static int
670acpi_cpu_shutdown(device_t dev)
671{
672    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
673
674    /* Allow children to shutdown first. */
675    bus_generic_shutdown(dev);
676
677    /*
678     * Disable any entry to the idle function.
679     */
680    disable_idle(device_get_softc(dev));
681
682    /*
683     * CPU devices are not truly detached and remain referenced,
684     * so their resources are not freed.
685     */
686
687    return_VALUE (0);
688}
689
690static void
691acpi_cpu_cx_probe(struct acpi_cpu_softc *sc)
692{
693    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
694
695    /* Use initial sleep value of 1 sec. to start with lowest idle state. */
696    sc->cpu_prev_sleep = 1000000;
697    sc->cpu_cx_lowest = 0;
698    sc->cpu_cx_lowest_lim = 0;
699
700    /*
701     * Check for the ACPI 2.0 _CST sleep states object. If we can't find
702     * any, we'll revert to generic FADT/P_BLK Cx control method which will
703     * be handled by acpi_cpu_startup. We need to defer to after having
704     * probed all the cpus in the system before probing for generic Cx
705     * states as we may already have found cpus with valid _CST packages
706     */
707    if (!cpu_cx_generic && acpi_cpu_cx_cst(sc) != 0) {
708	/*
709	 * We were unable to find a _CST package for this cpu or there
710	 * was an error parsing it. Switch back to generic mode.
711	 */
712	cpu_cx_generic = TRUE;
713	if (bootverbose)
714	    device_printf(sc->cpu_dev, "switching to generic Cx mode\n");
715    }
716
717    /*
718     * TODO: _CSD Package should be checked here.
719     */
720}
721
722static void
723acpi_cpu_generic_cx_probe(struct acpi_cpu_softc *sc)
724{
725    ACPI_GENERIC_ADDRESS	 gas;
726    struct acpi_cx		*cx_ptr;
727
728    sc->cpu_cx_count = 0;
729    cx_ptr = sc->cpu_cx_states;
730
731    /* Use initial sleep value of 1 sec. to start with lowest idle state. */
732    sc->cpu_prev_sleep = 1000000;
733
734    /* C1 has been required since just after ACPI 1.0 */
735    cx_ptr->type = ACPI_STATE_C1;
736    cx_ptr->trans_lat = 0;
737    cx_ptr++;
738    sc->cpu_non_c2 = sc->cpu_cx_count;
739    sc->cpu_non_c3 = sc->cpu_cx_count;
740    sc->cpu_cx_count++;
741
742    /*
743     * The spec says P_BLK must be 6 bytes long.  However, some systems
744     * use it to indicate a fractional set of features present so we
745     * take 5 as C2.  Some may also have a value of 7 to indicate
746     * another C3 but most use _CST for this (as required) and having
747     * "only" C1-C3 is not a hardship.
748     */
749    if (sc->cpu_p_blk_len < 5)
750	return;
751
752    /* Validate and allocate resources for C2 (P_LVL2). */
753    gas.SpaceId = ACPI_ADR_SPACE_SYSTEM_IO;
754    gas.BitWidth = 8;
755    if (AcpiGbl_FADT.C2Latency <= 100) {
756	gas.Address = sc->cpu_p_blk + 4;
757	cx_ptr->res_rid = 0;
758	acpi_bus_alloc_gas(sc->cpu_dev, &cx_ptr->res_type, &cx_ptr->res_rid,
759	    &gas, &cx_ptr->p_lvlx, RF_SHAREABLE);
760	if (cx_ptr->p_lvlx != NULL) {
761	    cx_ptr->type = ACPI_STATE_C2;
762	    cx_ptr->trans_lat = AcpiGbl_FADT.C2Latency;
763	    cx_ptr++;
764	    sc->cpu_non_c3 = sc->cpu_cx_count;
765	    sc->cpu_cx_count++;
766	}
767    }
768    if (sc->cpu_p_blk_len < 6)
769	return;
770
771    /* Validate and allocate resources for C3 (P_LVL3). */
772    if (AcpiGbl_FADT.C3Latency <= 1000 && !(cpu_quirks & CPU_QUIRK_NO_C3)) {
773	gas.Address = sc->cpu_p_blk + 5;
774	cx_ptr->res_rid = 1;
775	acpi_bus_alloc_gas(sc->cpu_dev, &cx_ptr->res_type, &cx_ptr->res_rid,
776	    &gas, &cx_ptr->p_lvlx, RF_SHAREABLE);
777	if (cx_ptr->p_lvlx != NULL) {
778	    cx_ptr->type = ACPI_STATE_C3;
779	    cx_ptr->trans_lat = AcpiGbl_FADT.C3Latency;
780	    cx_ptr++;
781	    sc->cpu_cx_count++;
782	}
783    }
784}
785
786#if defined(__i386__) || defined(__amd64__)
787static void
788acpi_cpu_cx_cst_mwait(struct acpi_cx *cx_ptr, uint64_t address, int accsize)
789{
790
791	cx_ptr->do_mwait = true;
792	cx_ptr->mwait_hint = address & 0xffffffff;
793	cx_ptr->mwait_hw_coord = (accsize & CST_FFH_MWAIT_HW_COORD) != 0;
794	cx_ptr->mwait_bm_avoidance = (accsize & CST_FFH_MWAIT_BM_AVOID) != 0;
795}
796#endif
797
798static void
799acpi_cpu_cx_cst_free_plvlx(device_t cpu_dev, struct acpi_cx *cx_ptr)
800{
801
802	if (cx_ptr->p_lvlx == NULL)
803		return;
804	bus_release_resource(cpu_dev, cx_ptr->res_type, cx_ptr->res_rid,
805	    cx_ptr->p_lvlx);
806	cx_ptr->p_lvlx = NULL;
807}
808
809/*
810 * Parse a _CST package and set up its Cx states.  Since the _CST object
811 * can change dynamically, our notify handler may call this function
812 * to clean up and probe the new _CST package.
813 */
814static int
815acpi_cpu_cx_cst(struct acpi_cpu_softc *sc)
816{
817    struct	 acpi_cx *cx_ptr;
818    ACPI_STATUS	 status;
819    ACPI_BUFFER	 buf;
820    ACPI_OBJECT	*top;
821    ACPI_OBJECT	*pkg;
822    uint32_t	 count;
823    int		 i;
824#if defined(__i386__) || defined(__amd64__)
825    uint64_t	 address;
826    int		 vendor, class, accsize;
827#endif
828
829    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
830
831    buf.Pointer = NULL;
832    buf.Length = ACPI_ALLOCATE_BUFFER;
833    status = AcpiEvaluateObject(sc->cpu_handle, "_CST", NULL, &buf);
834    if (ACPI_FAILURE(status))
835	return (ENXIO);
836
837    /* _CST is a package with a count and at least one Cx package. */
838    top = (ACPI_OBJECT *)buf.Pointer;
839    if (!ACPI_PKG_VALID(top, 2) || acpi_PkgInt32(top, 0, &count) != 0) {
840	device_printf(sc->cpu_dev, "invalid _CST package\n");
841	AcpiOsFree(buf.Pointer);
842	return (ENXIO);
843    }
844    if (count != top->Package.Count - 1) {
845	device_printf(sc->cpu_dev, "invalid _CST state count (%d != %d)\n",
846	       count, top->Package.Count - 1);
847	count = top->Package.Count - 1;
848    }
849    if (count > MAX_CX_STATES) {
850	device_printf(sc->cpu_dev, "_CST has too many states (%d)\n", count);
851	count = MAX_CX_STATES;
852    }
853
854    sc->cpu_non_c2 = 0;
855    sc->cpu_non_c3 = 0;
856    sc->cpu_cx_count = 0;
857    cx_ptr = sc->cpu_cx_states;
858
859    /*
860     * C1 has been required since just after ACPI 1.0.
861     * Reserve the first slot for it.
862     */
863    cx_ptr->type = ACPI_STATE_C0;
864    cx_ptr++;
865    sc->cpu_cx_count++;
866
867    /* Set up all valid states. */
868    for (i = 0; i < count; i++) {
869	pkg = &top->Package.Elements[i + 1];
870	if (!ACPI_PKG_VALID(pkg, 4) ||
871	    acpi_PkgInt32(pkg, 1, &cx_ptr->type) != 0 ||
872	    acpi_PkgInt32(pkg, 2, &cx_ptr->trans_lat) != 0 ||
873	    acpi_PkgInt32(pkg, 3, &cx_ptr->power) != 0) {
874
875	    device_printf(sc->cpu_dev, "skipping invalid Cx state package\n");
876	    continue;
877	}
878
879	/* Validate the state to see if we should use it. */
880	switch (cx_ptr->type) {
881	case ACPI_STATE_C1:
882	    acpi_cpu_cx_cst_free_plvlx(sc->cpu_dev, cx_ptr);
883#if defined(__i386__) || defined(__amd64__)
884	    if (acpi_PkgFFH_IntelCpu(pkg, 0, &vendor, &class, &address,
885	      &accsize) == 0 && vendor == CST_FFH_VENDOR_INTEL) {
886		if (class == CST_FFH_INTEL_CL_C1IO) {
887		    /* C1 I/O then Halt */
888		    cx_ptr->res_rid = sc->cpu_cx_count;
889		    bus_set_resource(sc->cpu_dev, SYS_RES_IOPORT,
890		      cx_ptr->res_rid, address, 1);
891		    cx_ptr->p_lvlx = bus_alloc_resource_any(sc->cpu_dev,
892		      SYS_RES_IOPORT, &cx_ptr->res_rid, RF_ACTIVE |
893		      RF_SHAREABLE);
894		    if (cx_ptr->p_lvlx == NULL) {
895			bus_delete_resource(sc->cpu_dev, SYS_RES_IOPORT,
896			  cx_ptr->res_rid);
897			device_printf(sc->cpu_dev,
898			  "C1 I/O failed to allocate port %d, "
899			  "degrading to C1 Halt", (int)address);
900		    }
901		} else if (class == CST_FFH_INTEL_CL_MWAIT) {
902		    acpi_cpu_cx_cst_mwait(cx_ptr, address, accsize);
903		}
904	    }
905#endif
906	    if (sc->cpu_cx_states[0].type == ACPI_STATE_C0) {
907		/* This is the first C1 state.  Use the reserved slot. */
908		sc->cpu_cx_states[0] = *cx_ptr;
909	    } else {
910		sc->cpu_non_c2 = sc->cpu_cx_count;
911		sc->cpu_non_c3 = sc->cpu_cx_count;
912		cx_ptr++;
913		sc->cpu_cx_count++;
914	    }
915	    continue;
916	case ACPI_STATE_C2:
917	    sc->cpu_non_c3 = sc->cpu_cx_count;
918	    break;
919	case ACPI_STATE_C3:
920	default:
921	    if ((cpu_quirks & CPU_QUIRK_NO_C3) != 0) {
922		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
923				 "acpi_cpu%d: C3[%d] not available.\n",
924				 device_get_unit(sc->cpu_dev), i));
925		continue;
926	    }
927	    break;
928	}
929
930	/* Free up any previous register. */
931	acpi_cpu_cx_cst_free_plvlx(sc->cpu_dev, cx_ptr);
932
933	/* Allocate the control register for C2 or C3. */
934#if defined(__i386__) || defined(__amd64__)
935	if (acpi_PkgFFH_IntelCpu(pkg, 0, &vendor, &class, &address,
936	  &accsize) == 0 && vendor == CST_FFH_VENDOR_INTEL &&
937	  class == CST_FFH_INTEL_CL_MWAIT) {
938	    /* Native C State Instruction use (mwait) */
939	    acpi_cpu_cx_cst_mwait(cx_ptr, address, accsize);
940	    ACPI_DEBUG_PRINT((ACPI_DB_INFO,
941	      "acpi_cpu%d: Got C%d/mwait - %d latency\n",
942	      device_get_unit(sc->cpu_dev), cx_ptr->type, cx_ptr->trans_lat));
943	    cx_ptr++;
944	    sc->cpu_cx_count++;
945	} else
946#endif
947	{
948	    cx_ptr->res_rid = sc->cpu_cx_count;
949	    acpi_PkgGas(sc->cpu_dev, pkg, 0, &cx_ptr->res_type,
950		&cx_ptr->res_rid, &cx_ptr->p_lvlx, RF_SHAREABLE);
951	    if (cx_ptr->p_lvlx) {
952		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
953		     "acpi_cpu%d: Got C%d - %d latency\n",
954		     device_get_unit(sc->cpu_dev), cx_ptr->type,
955		     cx_ptr->trans_lat));
956		cx_ptr++;
957		sc->cpu_cx_count++;
958	    }
959	}
960    }
961    AcpiOsFree(buf.Pointer);
962
963    /* If C1 state was not found, we need one now. */
964    cx_ptr = sc->cpu_cx_states;
965    if (cx_ptr->type == ACPI_STATE_C0) {
966	cx_ptr->type = ACPI_STATE_C1;
967	cx_ptr->trans_lat = 0;
968    }
969
970    return (0);
971}
972
973/*
974 * Call this *after* all CPUs have been attached.
975 */
976static void
977acpi_cpu_startup(void *arg)
978{
979    struct acpi_cpu_softc *sc;
980    int i;
981
982    /* Get set of CPU devices */
983    devclass_get_devices(acpi_cpu_devclass, &cpu_devices, &cpu_ndevices);
984
985    /*
986     * Setup any quirks that might necessary now that we have probed
987     * all the CPUs
988     */
989    acpi_cpu_quirks();
990
991    if (cpu_cx_generic) {
992	/*
993	 * We are using generic Cx mode, probe for available Cx states
994	 * for all processors.
995	 */
996	for (i = 0; i < cpu_ndevices; i++) {
997	    sc = device_get_softc(cpu_devices[i]);
998	    acpi_cpu_generic_cx_probe(sc);
999	}
1000    } else {
1001	/*
1002	 * We are using _CST mode, remove C3 state if necessary.
1003	 * As we now know for sure that we will be using _CST mode
1004	 * install our notify handler.
1005	 */
1006	for (i = 0; i < cpu_ndevices; i++) {
1007	    sc = device_get_softc(cpu_devices[i]);
1008	    if (cpu_quirks & CPU_QUIRK_NO_C3) {
1009		sc->cpu_cx_count = min(sc->cpu_cx_count, sc->cpu_non_c3 + 1);
1010	    }
1011	    AcpiInstallNotifyHandler(sc->cpu_handle, ACPI_DEVICE_NOTIFY,
1012		acpi_cpu_notify, sc);
1013	}
1014    }
1015
1016    /* Perform Cx final initialization. */
1017    for (i = 0; i < cpu_ndevices; i++) {
1018	sc = device_get_softc(cpu_devices[i]);
1019	acpi_cpu_startup_cx(sc);
1020    }
1021
1022    /* Add a sysctl handler to handle global Cx lowest setting */
1023    SYSCTL_ADD_PROC(&cpu_sysctl_ctx, SYSCTL_CHILDREN(cpu_sysctl_tree),
1024	OID_AUTO, "cx_lowest", CTLTYPE_STRING | CTLFLAG_RW,
1025	NULL, 0, acpi_cpu_global_cx_lowest_sysctl, "A",
1026	"Global lowest Cx sleep state to use");
1027
1028    /* Take over idling from cpu_idle_default(). */
1029    cpu_cx_lowest_lim = 0;
1030    for (i = 0; i < cpu_ndevices; i++) {
1031	sc = device_get_softc(cpu_devices[i]);
1032	enable_idle(sc);
1033    }
1034#if defined(__i386__) || defined(__amd64__)
1035    cpu_idle_hook = acpi_cpu_idle;
1036#endif
1037}
1038
1039static void
1040acpi_cpu_cx_list(struct acpi_cpu_softc *sc)
1041{
1042    struct sbuf sb;
1043    int i;
1044
1045    /*
1046     * Set up the list of Cx states
1047     */
1048    sbuf_new(&sb, sc->cpu_cx_supported, sizeof(sc->cpu_cx_supported),
1049	SBUF_FIXEDLEN);
1050    for (i = 0; i < sc->cpu_cx_count; i++)
1051	sbuf_printf(&sb, "C%d/%d/%d ", i + 1, sc->cpu_cx_states[i].type,
1052	    sc->cpu_cx_states[i].trans_lat);
1053    sbuf_trim(&sb);
1054    sbuf_finish(&sb);
1055}
1056
1057static void
1058acpi_cpu_startup_cx(struct acpi_cpu_softc *sc)
1059{
1060    acpi_cpu_cx_list(sc);
1061
1062    SYSCTL_ADD_STRING(&sc->cpu_sysctl_ctx,
1063		      SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
1064		      OID_AUTO, "cx_supported", CTLFLAG_RD,
1065		      sc->cpu_cx_supported, 0,
1066		      "Cx/microsecond values for supported Cx states");
1067    SYSCTL_ADD_PROC(&sc->cpu_sysctl_ctx,
1068		    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
1069		    OID_AUTO, "cx_lowest", CTLTYPE_STRING | CTLFLAG_RW,
1070		    (void *)sc, 0, acpi_cpu_cx_lowest_sysctl, "A",
1071		    "lowest Cx sleep state to use");
1072    SYSCTL_ADD_PROC(&sc->cpu_sysctl_ctx,
1073		    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
1074		    OID_AUTO, "cx_usage", CTLTYPE_STRING | CTLFLAG_RD,
1075		    (void *)sc, 0, acpi_cpu_usage_sysctl, "A",
1076		    "percent usage for each Cx state");
1077    SYSCTL_ADD_PROC(&sc->cpu_sysctl_ctx,
1078		    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
1079		    OID_AUTO, "cx_usage_counters", CTLTYPE_STRING | CTLFLAG_RD,
1080		    (void *)sc, 0, acpi_cpu_usage_counters_sysctl, "A",
1081		    "Cx sleep state counters");
1082#if defined(__i386__) || defined(__amd64__)
1083    SYSCTL_ADD_PROC(&sc->cpu_sysctl_ctx,
1084		    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
1085		    OID_AUTO, "cx_method", CTLTYPE_STRING | CTLFLAG_RD,
1086		    (void *)sc, 0, acpi_cpu_method_sysctl, "A",
1087		    "Cx entrance methods");
1088#endif
1089
1090    /* Signal platform that we can handle _CST notification. */
1091    if (!cpu_cx_generic && cpu_cst_cnt != 0) {
1092	ACPI_LOCK(acpi);
1093	AcpiOsWritePort(cpu_smi_cmd, cpu_cst_cnt, 8);
1094	ACPI_UNLOCK(acpi);
1095    }
1096}
1097
1098#if defined(__i386__) || defined(__amd64__)
1099/*
1100 * Idle the CPU in the lowest state possible.  This function is called with
1101 * interrupts disabled.  Note that once it re-enables interrupts, a task
1102 * switch can occur so do not access shared data (i.e. the softc) after
1103 * interrupts are re-enabled.
1104 */
1105static void
1106acpi_cpu_idle(sbintime_t sbt)
1107{
1108    struct	acpi_cpu_softc *sc;
1109    struct	acpi_cx *cx_next;
1110    uint64_t	start_ticks, end_ticks;
1111    uint32_t	start_time, end_time;
1112    ACPI_STATUS	status;
1113    int		bm_active, cx_next_idx, i, us;
1114
1115    /*
1116     * Look up our CPU id to get our softc.  If it's NULL, we'll use C1
1117     * since there is no ACPI processor object for this CPU.  This occurs
1118     * for logical CPUs in the HTT case.
1119     */
1120    sc = cpu_softc[PCPU_GET(cpuid)];
1121    if (sc == NULL) {
1122	acpi_cpu_c1();
1123	return;
1124    }
1125
1126    /* If disabled, take the safe path. */
1127    if (is_idle_disabled(sc)) {
1128	acpi_cpu_c1();
1129	return;
1130    }
1131
1132    /* Find the lowest state that has small enough latency. */
1133    us = sc->cpu_prev_sleep;
1134    if (sbt >= 0 && us > (sbt >> 12))
1135	us = (sbt >> 12);
1136    cx_next_idx = 0;
1137    if (cpu_disable_c2_sleep)
1138	i = min(sc->cpu_cx_lowest, sc->cpu_non_c2);
1139    else if (cpu_disable_c3_sleep)
1140	i = min(sc->cpu_cx_lowest, sc->cpu_non_c3);
1141    else
1142	i = sc->cpu_cx_lowest;
1143    for (; i >= 0; i--) {
1144	if (sc->cpu_cx_states[i].trans_lat * 3 <= us) {
1145	    cx_next_idx = i;
1146	    break;
1147	}
1148    }
1149
1150    /*
1151     * Check for bus master activity.  If there was activity, clear
1152     * the bit and use the lowest non-C3 state.  Note that the USB
1153     * driver polling for new devices keeps this bit set all the
1154     * time if USB is loaded.
1155     */
1156    cx_next = &sc->cpu_cx_states[cx_next_idx];
1157    if ((cpu_quirks & CPU_QUIRK_NO_BM_CTRL) == 0 &&
1158	cx_next_idx > sc->cpu_non_c3 &&
1159	(!cx_next->do_mwait || cx_next->mwait_bm_avoidance)) {
1160	status = AcpiReadBitRegister(ACPI_BITREG_BUS_MASTER_STATUS, &bm_active);
1161	if (ACPI_SUCCESS(status) && bm_active != 0) {
1162	    AcpiWriteBitRegister(ACPI_BITREG_BUS_MASTER_STATUS, 1);
1163	    cx_next_idx = sc->cpu_non_c3;
1164	    cx_next = &sc->cpu_cx_states[cx_next_idx];
1165	}
1166    }
1167
1168    /* Select the next state and update statistics. */
1169    sc->cpu_cx_stats[cx_next_idx]++;
1170    KASSERT(cx_next->type != ACPI_STATE_C0, ("acpi_cpu_idle: C0 sleep"));
1171
1172    /*
1173     * Execute HLT (or equivalent) and wait for an interrupt.  We can't
1174     * precisely calculate the time spent in C1 since the place we wake up
1175     * is an ISR.  Assume we slept no more then half of quantum, unless
1176     * we are called inside critical section, delaying context switch.
1177     */
1178    if (cx_next->type == ACPI_STATE_C1) {
1179	start_ticks = cpu_ticks();
1180	if (cx_next->p_lvlx != NULL) {
1181	    /* C1 I/O then Halt */
1182	    CPU_GET_REG(cx_next->p_lvlx, 1);
1183	}
1184	if (cx_next->do_mwait)
1185	    acpi_cpu_idle_mwait(cx_next->mwait_hint);
1186	else
1187	    acpi_cpu_c1();
1188	end_ticks = cpu_ticks();
1189	/* acpi_cpu_c1() returns with interrupts enabled. */
1190	if (cx_next->do_mwait)
1191	    ACPI_ENABLE_IRQS();
1192	end_time = ((end_ticks - start_ticks) << 20) / cpu_tickrate();
1193	if (!cx_next->do_mwait && curthread->td_critnest == 0)
1194		end_time = min(end_time, 500000 / hz);
1195	sc->cpu_prev_sleep = (sc->cpu_prev_sleep * 3 + end_time) / 4;
1196	return;
1197    }
1198
1199    /*
1200     * For C3, disable bus master arbitration and enable bus master wake
1201     * if BM control is available, otherwise flush the CPU cache.
1202     */
1203    if (cx_next->type == ACPI_STATE_C3) {
1204	if ((cpu_quirks & CPU_QUIRK_NO_BM_CTRL) == 0) {
1205	    AcpiWriteBitRegister(ACPI_BITREG_ARB_DISABLE, 1);
1206	    AcpiWriteBitRegister(ACPI_BITREG_BUS_MASTER_RLD, 1);
1207	} else
1208	    ACPI_FLUSH_CPU_CACHE();
1209    }
1210
1211    /*
1212     * Read from P_LVLx to enter C2(+), checking time spent asleep.
1213     * Use the ACPI timer for measuring sleep time.  Since we need to
1214     * get the time very close to the CPU start/stop clock logic, this
1215     * is the only reliable time source.
1216     */
1217    if (cx_next->type == ACPI_STATE_C3) {
1218	AcpiGetTimer(&start_time);
1219	start_ticks = 0;
1220    } else {
1221	start_time = 0;
1222	start_ticks = cpu_ticks();
1223    }
1224    if (cx_next->do_mwait) {
1225	acpi_cpu_idle_mwait(cx_next->mwait_hint);
1226    } else {
1227	CPU_GET_REG(cx_next->p_lvlx, 1);
1228	/*
1229	 * Read the end time twice.  Since it may take an arbitrary time
1230	 * to enter the idle state, the first read may be executed before
1231	 * the processor has stopped.  Doing it again provides enough
1232	 * margin that we are certain to have a correct value.
1233	 */
1234	AcpiGetTimer(&end_time);
1235    }
1236
1237    if (cx_next->type == ACPI_STATE_C3)
1238	AcpiGetTimer(&end_time);
1239    else
1240	end_ticks = cpu_ticks();
1241
1242    /* Enable bus master arbitration and disable bus master wakeup. */
1243    if (cx_next->type == ACPI_STATE_C3 &&
1244      (cpu_quirks & CPU_QUIRK_NO_BM_CTRL) == 0) {
1245	AcpiWriteBitRegister(ACPI_BITREG_ARB_DISABLE, 0);
1246	AcpiWriteBitRegister(ACPI_BITREG_BUS_MASTER_RLD, 0);
1247    }
1248    ACPI_ENABLE_IRQS();
1249
1250    if (cx_next->type == ACPI_STATE_C3)
1251	AcpiGetTimerDuration(start_time, end_time, &end_time);
1252    else
1253	end_time = ((end_ticks - start_ticks) << 20) / cpu_tickrate();
1254    sc->cpu_prev_sleep = (sc->cpu_prev_sleep * 3 + end_time) / 4;
1255}
1256#endif
1257
1258/*
1259 * Re-evaluate the _CST object when we are notified that it changed.
1260 */
1261static void
1262acpi_cpu_notify(ACPI_HANDLE h, UINT32 notify, void *context)
1263{
1264    struct acpi_cpu_softc *sc = (struct acpi_cpu_softc *)context;
1265
1266    if (notify != ACPI_NOTIFY_CX_STATES)
1267	return;
1268
1269    /*
1270     * C-state data for target CPU is going to be in flux while we execute
1271     * acpi_cpu_cx_cst, so disable entering acpi_cpu_idle.
1272     * Also, it may happen that multiple ACPI taskqueues may concurrently
1273     * execute notifications for the same CPU.  ACPI_SERIAL is used to
1274     * protect against that.
1275     */
1276    ACPI_SERIAL_BEGIN(cpu);
1277    disable_idle(sc);
1278
1279    /* Update the list of Cx states. */
1280    acpi_cpu_cx_cst(sc);
1281    acpi_cpu_cx_list(sc);
1282    acpi_cpu_set_cx_lowest(sc);
1283
1284    enable_idle(sc);
1285    ACPI_SERIAL_END(cpu);
1286
1287    acpi_UserNotify("PROCESSOR", sc->cpu_handle, notify);
1288}
1289
1290static void
1291acpi_cpu_quirks(void)
1292{
1293    ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
1294
1295    /*
1296     * Bus mastering arbitration control is needed to keep caches coherent
1297     * while sleeping in C3.  If it's not present but a working flush cache
1298     * instruction is present, flush the caches before entering C3 instead.
1299     * Otherwise, just disable C3 completely.
1300     */
1301    if (AcpiGbl_FADT.Pm2ControlBlock == 0 ||
1302	AcpiGbl_FADT.Pm2ControlLength == 0) {
1303	if ((AcpiGbl_FADT.Flags & ACPI_FADT_WBINVD) &&
1304	    (AcpiGbl_FADT.Flags & ACPI_FADT_WBINVD_FLUSH) == 0) {
1305	    cpu_quirks |= CPU_QUIRK_NO_BM_CTRL;
1306	    ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1307		"acpi_cpu: no BM control, using flush cache method\n"));
1308	} else {
1309	    cpu_quirks |= CPU_QUIRK_NO_C3;
1310	    ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1311		"acpi_cpu: no BM control, C3 not available\n"));
1312	}
1313    }
1314
1315    /*
1316     * If we are using generic Cx mode, C3 on multiple CPUs requires using
1317     * the expensive flush cache instruction.
1318     */
1319    if (cpu_cx_generic && mp_ncpus > 1) {
1320	cpu_quirks |= CPU_QUIRK_NO_BM_CTRL;
1321	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1322	    "acpi_cpu: SMP, using flush cache mode for C3\n"));
1323    }
1324
1325    /* Look for various quirks of the PIIX4 part. */
1326    acpi_cpu_quirks_piix4();
1327}
1328
1329static void
1330acpi_cpu_quirks_piix4(void)
1331{
1332#ifdef __i386__
1333    device_t acpi_dev;
1334    uint32_t val;
1335    ACPI_STATUS status;
1336
1337    acpi_dev = pci_find_device(PCI_VENDOR_INTEL, PCI_DEVICE_82371AB_3);
1338    if (acpi_dev != NULL) {
1339	switch (pci_get_revid(acpi_dev)) {
1340	/*
1341	 * Disable C3 support for all PIIX4 chipsets.  Some of these parts
1342	 * do not report the BMIDE status to the BM status register and
1343	 * others have a livelock bug if Type-F DMA is enabled.  Linux
1344	 * works around the BMIDE bug by reading the BM status directly
1345	 * but we take the simpler approach of disabling C3 for these
1346	 * parts.
1347	 *
1348	 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
1349	 * Livelock") from the January 2002 PIIX4 specification update.
1350	 * Applies to all PIIX4 models.
1351	 *
1352	 * Also, make sure that all interrupts cause a "Stop Break"
1353	 * event to exit from C2 state.
1354	 * Also, BRLD_EN_BM (ACPI_BITREG_BUS_MASTER_RLD in ACPI-speak)
1355	 * should be set to zero, otherwise it causes C2 to short-sleep.
1356	 * PIIX4 doesn't properly support C3 and bus master activity
1357	 * need not break out of C2.
1358	 */
1359	case PCI_REVISION_A_STEP:
1360	case PCI_REVISION_B_STEP:
1361	case PCI_REVISION_4E:
1362	case PCI_REVISION_4M:
1363	    cpu_quirks |= CPU_QUIRK_NO_C3;
1364	    ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1365		"acpi_cpu: working around PIIX4 bug, disabling C3\n"));
1366
1367	    val = pci_read_config(acpi_dev, PIIX4_DEVACTB_REG, 4);
1368	    if ((val & PIIX4_STOP_BREAK_MASK) != PIIX4_STOP_BREAK_MASK) {
1369		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1370		    "acpi_cpu: PIIX4: enabling IRQs to generate Stop Break\n"));
1371	    	val |= PIIX4_STOP_BREAK_MASK;
1372		pci_write_config(acpi_dev, PIIX4_DEVACTB_REG, val, 4);
1373	    }
1374	    status = AcpiReadBitRegister(ACPI_BITREG_BUS_MASTER_RLD, &val);
1375	    if (ACPI_SUCCESS(status) && val != 0) {
1376		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1377		    "acpi_cpu: PIIX4: reset BRLD_EN_BM\n"));
1378		AcpiWriteBitRegister(ACPI_BITREG_BUS_MASTER_RLD, 0);
1379	    }
1380	    break;
1381	default:
1382	    break;
1383	}
1384    }
1385#endif
1386}
1387
1388static int
1389acpi_cpu_usage_sysctl(SYSCTL_HANDLER_ARGS)
1390{
1391    struct acpi_cpu_softc *sc;
1392    struct sbuf	 sb;
1393    char	 buf[128];
1394    int		 i;
1395    uintmax_t	 fract, sum, whole;
1396
1397    sc = (struct acpi_cpu_softc *) arg1;
1398    sum = 0;
1399    for (i = 0; i < sc->cpu_cx_count; i++)
1400	sum += sc->cpu_cx_stats[i];
1401    sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
1402    for (i = 0; i < sc->cpu_cx_count; i++) {
1403	if (sum > 0) {
1404	    whole = (uintmax_t)sc->cpu_cx_stats[i] * 100;
1405	    fract = (whole % sum) * 100;
1406	    sbuf_printf(&sb, "%u.%02u%% ", (u_int)(whole / sum),
1407		(u_int)(fract / sum));
1408	} else
1409	    sbuf_printf(&sb, "0.00%% ");
1410    }
1411    sbuf_printf(&sb, "last %dus", sc->cpu_prev_sleep);
1412    sbuf_trim(&sb);
1413    sbuf_finish(&sb);
1414    sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
1415    sbuf_delete(&sb);
1416
1417    return (0);
1418}
1419
1420/*
1421 * XXX TODO: actually add support to count each entry/exit
1422 * from the Cx states.
1423 */
1424static int
1425acpi_cpu_usage_counters_sysctl(SYSCTL_HANDLER_ARGS)
1426{
1427    struct acpi_cpu_softc *sc;
1428    struct sbuf	 sb;
1429    char	 buf[128];
1430    int		 i;
1431
1432    sc = (struct acpi_cpu_softc *) arg1;
1433
1434    /* Print out the raw counters */
1435    sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
1436
1437    for (i = 0; i < sc->cpu_cx_count; i++) {
1438        sbuf_printf(&sb, "%u ", sc->cpu_cx_stats[i]);
1439    }
1440
1441    sbuf_trim(&sb);
1442    sbuf_finish(&sb);
1443    sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
1444    sbuf_delete(&sb);
1445
1446    return (0);
1447}
1448
1449#if defined(__i386__) || defined(__amd64__)
1450static int
1451acpi_cpu_method_sysctl(SYSCTL_HANDLER_ARGS)
1452{
1453	struct acpi_cpu_softc *sc;
1454	struct acpi_cx *cx;
1455	struct sbuf sb;
1456	char buf[128];
1457	int i;
1458
1459	sc = (struct acpi_cpu_softc *)arg1;
1460	sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
1461	for (i = 0; i < sc->cpu_cx_count; i++) {
1462		cx = &sc->cpu_cx_states[i];
1463		sbuf_printf(&sb, "C%d/", i + 1);
1464		if (cx->do_mwait) {
1465			sbuf_cat(&sb, "mwait");
1466			if (cx->mwait_hw_coord)
1467				sbuf_cat(&sb, "/hwc");
1468			if (cx->mwait_bm_avoidance)
1469				sbuf_cat(&sb, "/bma");
1470		} else if (cx->type == ACPI_STATE_C1) {
1471			sbuf_cat(&sb, "hlt");
1472		} else {
1473			sbuf_cat(&sb, "io");
1474		}
1475		if (cx->type == ACPI_STATE_C1 && cx->p_lvlx != NULL)
1476			sbuf_cat(&sb, "/iohlt");
1477		sbuf_putc(&sb, ' ');
1478	}
1479	sbuf_trim(&sb);
1480	sbuf_finish(&sb);
1481	sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
1482	sbuf_delete(&sb);
1483	return (0);
1484}
1485#endif
1486
1487static int
1488acpi_cpu_set_cx_lowest(struct acpi_cpu_softc *sc)
1489{
1490    int i;
1491
1492    ACPI_SERIAL_ASSERT(cpu);
1493    sc->cpu_cx_lowest = min(sc->cpu_cx_lowest_lim, sc->cpu_cx_count - 1);
1494
1495    /* If not disabling, cache the new lowest non-C3 state. */
1496    sc->cpu_non_c3 = 0;
1497    for (i = sc->cpu_cx_lowest; i >= 0; i--) {
1498	if (sc->cpu_cx_states[i].type < ACPI_STATE_C3) {
1499	    sc->cpu_non_c3 = i;
1500	    break;
1501	}
1502    }
1503
1504    /* Reset the statistics counters. */
1505    bzero(sc->cpu_cx_stats, sizeof(sc->cpu_cx_stats));
1506    return (0);
1507}
1508
1509static int
1510acpi_cpu_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS)
1511{
1512    struct	 acpi_cpu_softc *sc;
1513    char	 state[8];
1514    int		 val, error;
1515
1516    sc = (struct acpi_cpu_softc *) arg1;
1517    snprintf(state, sizeof(state), "C%d", sc->cpu_cx_lowest_lim + 1);
1518    error = sysctl_handle_string(oidp, state, sizeof(state), req);
1519    if (error != 0 || req->newptr == NULL)
1520	return (error);
1521    if (strlen(state) < 2 || toupper(state[0]) != 'C')
1522	return (EINVAL);
1523    if (strcasecmp(state, "Cmax") == 0)
1524	val = MAX_CX_STATES;
1525    else {
1526	val = (int) strtol(state + 1, NULL, 10);
1527	if (val < 1 || val > MAX_CX_STATES)
1528	    return (EINVAL);
1529    }
1530
1531    ACPI_SERIAL_BEGIN(cpu);
1532    sc->cpu_cx_lowest_lim = val - 1;
1533    acpi_cpu_set_cx_lowest(sc);
1534    ACPI_SERIAL_END(cpu);
1535
1536    return (0);
1537}
1538
1539static int
1540acpi_cpu_global_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS)
1541{
1542    struct	acpi_cpu_softc *sc;
1543    char	state[8];
1544    int		val, error, i;
1545
1546    snprintf(state, sizeof(state), "C%d", cpu_cx_lowest_lim + 1);
1547    error = sysctl_handle_string(oidp, state, sizeof(state), req);
1548    if (error != 0 || req->newptr == NULL)
1549	return (error);
1550    if (strlen(state) < 2 || toupper(state[0]) != 'C')
1551	return (EINVAL);
1552    if (strcasecmp(state, "Cmax") == 0)
1553	val = MAX_CX_STATES;
1554    else {
1555	val = (int) strtol(state + 1, NULL, 10);
1556	if (val < 1 || val > MAX_CX_STATES)
1557	    return (EINVAL);
1558    }
1559
1560    /* Update the new lowest useable Cx state for all CPUs. */
1561    ACPI_SERIAL_BEGIN(cpu);
1562    cpu_cx_lowest_lim = val - 1;
1563    for (i = 0; i < cpu_ndevices; i++) {
1564	sc = device_get_softc(cpu_devices[i]);
1565	sc->cpu_cx_lowest_lim = cpu_cx_lowest_lim;
1566	acpi_cpu_set_cx_lowest(sc);
1567    }
1568    ACPI_SERIAL_END(cpu);
1569
1570    return (0);
1571}
1572