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1  /*
2   *	Local APIC handling, local APIC timers
3   *
4   *	(c) 1999, 2000 Ingo Molnar <mingo@redhat.com>
5   *
6   *	Fixes
7   *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
8   *					thanks to Eric Gilmore
9   *					and Rolf G. Tews
10   *					for testing these extensively.
11   *	Maciej W. Rozycki	:	Various updates and fixes.
12   *	Mikael Pettersson	:	Power Management for UP-APIC.
13   *	Pavel Machek and
14   *	Mikael Pettersson	:	PM converted to driver model.
15   */
16  
17  #include <linux/init.h>
18  
19  #include <linux/mm.h>
20  #include <linux/delay.h>
21  #include <linux/bootmem.h>
22  #include <linux/interrupt.h>
23  #include <linux/mc146818rtc.h>
24  #include <linux/kernel_stat.h>
25  #include <linux/sysdev.h>
26  #include <linux/ioport.h>
27  #include <linux/cpu.h>
28  #include <linux/clockchips.h>
29  #include <linux/acpi_pmtmr.h>
30  #include <linux/module.h>
31  #include <linux/dmi.h>
32  #include <linux/dmar.h>
33  #include <linux/ftrace.h>
34  #include <linux/smp.h>
35  #include <linux/nmi.h>
36  #include <linux/timex.h>
37  
38  #include <asm/atomic.h>
39  #include <asm/mtrr.h>
40  #include <asm/mpspec.h>
41  #include <asm/desc.h>
42  #include <asm/arch_hooks.h>
43  #include <asm/hpet.h>
44  #include <asm/pgalloc.h>
45  #include <asm/i8253.h>
46  #include <asm/idle.h>
47  #include <asm/proto.h>
48  #include <asm/apic.h>
49  #include <asm/i8259.h>
50  #include <asm/smp.h>
51  
52  #include <mach_apic.h>
53  #include <mach_apicdef.h>
54  #include <mach_ipi.h>
55  
56  /*
57   * Sanity check
58   */
59  #if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
60  # error SPURIOUS_APIC_VECTOR definition error
61  #endif
62  
63  #ifdef CONFIG_X86_32
64  /*
65   * Knob to control our willingness to enable the local APIC.
66   *
67   * +1=force-enable
68   */
69  static int force_enable_local_apic;
70  /*
71   * APIC command line parameters
72   */
parse_lapic(char * arg)73  static int __init parse_lapic(char *arg)
74  {
75  	force_enable_local_apic = 1;
76  	return 0;
77  }
78  early_param("lapic", parse_lapic);
79  /* Local APIC was disabled by the BIOS and enabled by the kernel */
80  static int enabled_via_apicbase;
81  
82  #endif
83  
84  #ifdef CONFIG_X86_64
85  static int apic_calibrate_pmtmr __initdata;
setup_apicpmtimer(char * s)86  static __init int setup_apicpmtimer(char *s)
87  {
88  	apic_calibrate_pmtmr = 1;
89  	notsc_setup(NULL);
90  	return 0;
91  }
92  __setup("apicpmtimer", setup_apicpmtimer);
93  #endif
94  
95  #ifdef CONFIG_X86_64
96  #define HAVE_X2APIC
97  #endif
98  
99  #ifdef HAVE_X2APIC
100  int x2apic;
101  /* x2apic enabled before OS handover */
102  static int x2apic_preenabled;
103  static int disable_x2apic;
setup_nox2apic(char * str)104  static __init int setup_nox2apic(char *str)
105  {
106  	disable_x2apic = 1;
107  	setup_clear_cpu_cap(X86_FEATURE_X2APIC);
108  	return 0;
109  }
110  early_param("nox2apic", setup_nox2apic);
111  #endif
112  
113  unsigned long mp_lapic_addr;
114  int disable_apic;
115  /* Disable local APIC timer from the kernel commandline or via dmi quirk */
116  static int disable_apic_timer __cpuinitdata;
117  /* Local APIC timer works in C2 */
118  int local_apic_timer_c2_ok;
119  EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
120  
121  int first_system_vector = 0xfe;
122  
123  /*
124   * Debug level, exported for io_apic.c
125   */
126  unsigned int apic_verbosity;
127  
128  int pic_mode;
129  
130  /* Have we found an MP table */
131  int smp_found_config;
132  
133  static struct resource lapic_resource = {
134  	.name = "Local APIC",
135  	.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
136  };
137  
138  static unsigned int calibration_result;
139  
140  static int lapic_next_event(unsigned long delta,
141  			    struct clock_event_device *evt);
142  static void lapic_timer_setup(enum clock_event_mode mode,
143  			      struct clock_event_device *evt);
144  static void lapic_timer_broadcast(const struct cpumask *mask);
145  static void apic_pm_activate(void);
146  
147  /*
148   * The local apic timer can be used for any function which is CPU local.
149   */
150  static struct clock_event_device lapic_clockevent = {
151  	.name		= "lapic",
152  	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
153  			| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
154  	.shift		= 32,
155  	.set_mode	= lapic_timer_setup,
156  	.set_next_event	= lapic_next_event,
157  	.broadcast	= lapic_timer_broadcast,
158  	.rating		= 100,
159  	.irq		= -1,
160  };
161  static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
162  
163  static unsigned long apic_phys;
164  
165  /*
166   * Get the LAPIC version
167   */
lapic_get_version(void)168  static inline int lapic_get_version(void)
169  {
170  	return GET_APIC_VERSION(apic_read(APIC_LVR));
171  }
172  
173  /*
174   * Check, if the APIC is integrated or a separate chip
175   */
lapic_is_integrated(void)176  static inline int lapic_is_integrated(void)
177  {
178  #ifdef CONFIG_X86_64
179  	return 1;
180  #else
181  	return APIC_INTEGRATED(lapic_get_version());
182  #endif
183  }
184  
185  /*
186   * Check, whether this is a modern or a first generation APIC
187   */
modern_apic(void)188  static int modern_apic(void)
189  {
190  	/* AMD systems use old APIC versions, so check the CPU */
191  	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
192  	    boot_cpu_data.x86 >= 0xf)
193  		return 1;
194  	return lapic_get_version() >= 0x14;
195  }
196  
197  /*
198   * Paravirt kernels also might be using these below ops. So we still
199   * use generic apic_read()/apic_write(), which might be pointing to different
200   * ops in PARAVIRT case.
201   */
xapic_wait_icr_idle(void)202  void xapic_wait_icr_idle(void)
203  {
204  	while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
205  		cpu_relax();
206  }
207  
safe_xapic_wait_icr_idle(void)208  u32 safe_xapic_wait_icr_idle(void)
209  {
210  	u32 send_status;
211  	int timeout;
212  
213  	timeout = 0;
214  	do {
215  		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
216  		if (!send_status)
217  			break;
218  		udelay(100);
219  	} while (timeout++ < 1000);
220  
221  	return send_status;
222  }
223  
xapic_icr_write(u32 low,u32 id)224  void xapic_icr_write(u32 low, u32 id)
225  {
226  	apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
227  	apic_write(APIC_ICR, low);
228  }
229  
xapic_icr_read(void)230  static u64 xapic_icr_read(void)
231  {
232  	u32 icr1, icr2;
233  
234  	icr2 = apic_read(APIC_ICR2);
235  	icr1 = apic_read(APIC_ICR);
236  
237  	return icr1 | ((u64)icr2 << 32);
238  }
239  
240  static struct apic_ops xapic_ops = {
241  	.read = native_apic_mem_read,
242  	.write = native_apic_mem_write,
243  	.icr_read = xapic_icr_read,
244  	.icr_write = xapic_icr_write,
245  	.wait_icr_idle = xapic_wait_icr_idle,
246  	.safe_wait_icr_idle = safe_xapic_wait_icr_idle,
247  };
248  
249  struct apic_ops __read_mostly *apic_ops = &xapic_ops;
250  EXPORT_SYMBOL_GPL(apic_ops);
251  
252  #ifdef HAVE_X2APIC
x2apic_wait_icr_idle(void)253  static void x2apic_wait_icr_idle(void)
254  {
255  	/* no need to wait for icr idle in x2apic */
256  	return;
257  }
258  
safe_x2apic_wait_icr_idle(void)259  static u32 safe_x2apic_wait_icr_idle(void)
260  {
261  	/* no need to wait for icr idle in x2apic */
262  	return 0;
263  }
264  
x2apic_icr_write(u32 low,u32 id)265  void x2apic_icr_write(u32 low, u32 id)
266  {
267  	wrmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), ((__u64) id) << 32 | low);
268  }
269  
x2apic_icr_read(void)270  static u64 x2apic_icr_read(void)
271  {
272  	unsigned long val;
273  
274  	rdmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), val);
275  	return val;
276  }
277  
278  static struct apic_ops x2apic_ops = {
279  	.read = native_apic_msr_read,
280  	.write = native_apic_msr_write,
281  	.icr_read = x2apic_icr_read,
282  	.icr_write = x2apic_icr_write,
283  	.wait_icr_idle = x2apic_wait_icr_idle,
284  	.safe_wait_icr_idle = safe_x2apic_wait_icr_idle,
285  };
286  #endif
287  
288  /**
289   * enable_NMI_through_LVT0 - enable NMI through local vector table 0
290   */
enable_NMI_through_LVT0(void)291  void __cpuinit enable_NMI_through_LVT0(void)
292  {
293  	unsigned int v;
294  
295  	/* unmask and set to NMI */
296  	v = APIC_DM_NMI;
297  
298  	/* Level triggered for 82489DX (32bit mode) */
299  	if (!lapic_is_integrated())
300  		v |= APIC_LVT_LEVEL_TRIGGER;
301  
302  	apic_write(APIC_LVT0, v);
303  }
304  
305  #ifdef CONFIG_X86_32
306  /**
307   * get_physical_broadcast - Get number of physical broadcast IDs
308   */
get_physical_broadcast(void)309  int get_physical_broadcast(void)
310  {
311  	return modern_apic() ? 0xff : 0xf;
312  }
313  #endif
314  
315  /**
316   * lapic_get_maxlvt - get the maximum number of local vector table entries
317   */
lapic_get_maxlvt(void)318  int lapic_get_maxlvt(void)
319  {
320  	unsigned int v;
321  
322  	v = apic_read(APIC_LVR);
323  	/*
324  	 * - we always have APIC integrated on 64bit mode
325  	 * - 82489DXs do not report # of LVT entries
326  	 */
327  	return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
328  }
329  
330  /*
331   * Local APIC timer
332   */
333  
334  /* Clock divisor */
335  #define APIC_DIVISOR 16
336  
337  /*
338   * This function sets up the local APIC timer, with a timeout of
339   * 'clocks' APIC bus clock. During calibration we actually call
340   * this function twice on the boot CPU, once with a bogus timeout
341   * value, second time for real. The other (noncalibrating) CPUs
342   * call this function only once, with the real, calibrated value.
343   *
344   * We do reads before writes even if unnecessary, to get around the
345   * P5 APIC double write bug.
346   */
__setup_APIC_LVTT(unsigned int clocks,int oneshot,int irqen)347  static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
348  {
349  	unsigned int lvtt_value, tmp_value;
350  
351  	lvtt_value = LOCAL_TIMER_VECTOR;
352  	if (!oneshot)
353  		lvtt_value |= APIC_LVT_TIMER_PERIODIC;
354  	if (!lapic_is_integrated())
355  		lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
356  
357  	if (!irqen)
358  		lvtt_value |= APIC_LVT_MASKED;
359  
360  	apic_write(APIC_LVTT, lvtt_value);
361  
362  	/*
363  	 * Divide PICLK by 16
364  	 */
365  	tmp_value = apic_read(APIC_TDCR);
366  	apic_write(APIC_TDCR,
367  		(tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
368  		APIC_TDR_DIV_16);
369  
370  	if (!oneshot)
371  		apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
372  }
373  
374  /*
375   * Setup extended LVT, AMD specific (K8, family 10h)
376   *
377   * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
378   * MCE interrupts are supported. Thus MCE offset must be set to 0.
379   *
380   * If mask=1, the LVT entry does not generate interrupts while mask=0
381   * enables the vector. See also the BKDGs.
382   */
383  
384  #define APIC_EILVT_LVTOFF_MCE 0
385  #define APIC_EILVT_LVTOFF_IBS 1
386  
setup_APIC_eilvt(u8 lvt_off,u8 vector,u8 msg_type,u8 mask)387  static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
388  {
389  	unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
390  	unsigned int  v   = (mask << 16) | (msg_type << 8) | vector;
391  
392  	apic_write(reg, v);
393  }
394  
setup_APIC_eilvt_mce(u8 vector,u8 msg_type,u8 mask)395  u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
396  {
397  	setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
398  	return APIC_EILVT_LVTOFF_MCE;
399  }
400  
setup_APIC_eilvt_ibs(u8 vector,u8 msg_type,u8 mask)401  u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
402  {
403  	setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
404  	return APIC_EILVT_LVTOFF_IBS;
405  }
406  EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
407  
408  /*
409   * Program the next event, relative to now
410   */
lapic_next_event(unsigned long delta,struct clock_event_device * evt)411  static int lapic_next_event(unsigned long delta,
412  			    struct clock_event_device *evt)
413  {
414  	apic_write(APIC_TMICT, delta);
415  	return 0;
416  }
417  
418  /*
419   * Setup the lapic timer in periodic or oneshot mode
420   */
lapic_timer_setup(enum clock_event_mode mode,struct clock_event_device * evt)421  static void lapic_timer_setup(enum clock_event_mode mode,
422  			      struct clock_event_device *evt)
423  {
424  	unsigned long flags;
425  	unsigned int v;
426  
427  	/* Lapic used as dummy for broadcast ? */
428  	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
429  		return;
430  
431  	local_irq_save(flags);
432  
433  	switch (mode) {
434  	case CLOCK_EVT_MODE_PERIODIC:
435  	case CLOCK_EVT_MODE_ONESHOT:
436  		__setup_APIC_LVTT(calibration_result,
437  				  mode != CLOCK_EVT_MODE_PERIODIC, 1);
438  		break;
439  	case CLOCK_EVT_MODE_UNUSED:
440  	case CLOCK_EVT_MODE_SHUTDOWN:
441  		v = apic_read(APIC_LVTT);
442  		v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
443  		apic_write(APIC_LVTT, v);
444  		apic_write(APIC_TMICT, 0xffffffff);
445  		break;
446  	case CLOCK_EVT_MODE_RESUME:
447  		/* Nothing to do here */
448  		break;
449  	}
450  
451  	local_irq_restore(flags);
452  }
453  
454  /*
455   * Local APIC timer broadcast function
456   */
lapic_timer_broadcast(const struct cpumask * mask)457  static void lapic_timer_broadcast(const struct cpumask *mask)
458  {
459  #ifdef CONFIG_SMP
460  	send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
461  #endif
462  }
463  
464  /*
465   * Setup the local APIC timer for this CPU. Copy the initilized values
466   * of the boot CPU and register the clock event in the framework.
467   */
setup_APIC_timer(void)468  static void __cpuinit setup_APIC_timer(void)
469  {
470  	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
471  
472  	memcpy(levt, &lapic_clockevent, sizeof(*levt));
473  	levt->cpumask = cpumask_of(smp_processor_id());
474  
475  	clockevents_register_device(levt);
476  }
477  
478  /*
479   * In this functions we calibrate APIC bus clocks to the external timer.
480   *
481   * We want to do the calibration only once since we want to have local timer
482   * irqs syncron. CPUs connected by the same APIC bus have the very same bus
483   * frequency.
484   *
485   * This was previously done by reading the PIT/HPET and waiting for a wrap
486   * around to find out, that a tick has elapsed. I have a box, where the PIT
487   * readout is broken, so it never gets out of the wait loop again. This was
488   * also reported by others.
489   *
490   * Monitoring the jiffies value is inaccurate and the clockevents
491   * infrastructure allows us to do a simple substitution of the interrupt
492   * handler.
493   *
494   * The calibration routine also uses the pm_timer when possible, as the PIT
495   * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
496   * back to normal later in the boot process).
497   */
498  
499  #define LAPIC_CAL_LOOPS		(HZ/10)
500  
501  static __initdata int lapic_cal_loops = -1;
502  static __initdata long lapic_cal_t1, lapic_cal_t2;
503  static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
504  static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
505  static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
506  
507  /*
508   * Temporary interrupt handler.
509   */
lapic_cal_handler(struct clock_event_device * dev)510  static void __init lapic_cal_handler(struct clock_event_device *dev)
511  {
512  	unsigned long long tsc = 0;
513  	long tapic = apic_read(APIC_TMCCT);
514  	unsigned long pm = acpi_pm_read_early();
515  
516  	if (cpu_has_tsc)
517  		rdtscll(tsc);
518  
519  	switch (lapic_cal_loops++) {
520  	case 0:
521  		lapic_cal_t1 = tapic;
522  		lapic_cal_tsc1 = tsc;
523  		lapic_cal_pm1 = pm;
524  		lapic_cal_j1 = jiffies;
525  		break;
526  
527  	case LAPIC_CAL_LOOPS:
528  		lapic_cal_t2 = tapic;
529  		lapic_cal_tsc2 = tsc;
530  		if (pm < lapic_cal_pm1)
531  			pm += ACPI_PM_OVRRUN;
532  		lapic_cal_pm2 = pm;
533  		lapic_cal_j2 = jiffies;
534  		break;
535  	}
536  }
537  
calibrate_by_pmtimer(long deltapm,long * delta)538  static int __init calibrate_by_pmtimer(long deltapm, long *delta)
539  {
540  	const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
541  	const long pm_thresh = pm_100ms / 100;
542  	unsigned long mult;
543  	u64 res;
544  
545  #ifndef CONFIG_X86_PM_TIMER
546  	return -1;
547  #endif
548  
549  	apic_printk(APIC_VERBOSE, "... PM timer delta = %ld\n", deltapm);
550  
551  	/* Check, if the PM timer is available */
552  	if (!deltapm)
553  		return -1;
554  
555  	mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
556  
557  	if (deltapm > (pm_100ms - pm_thresh) &&
558  	    deltapm < (pm_100ms + pm_thresh)) {
559  		apic_printk(APIC_VERBOSE, "... PM timer result ok\n");
560  	} else {
561  		res = (((u64)deltapm) *  mult) >> 22;
562  		do_div(res, 1000000);
563  		pr_warning("APIC calibration not consistent "
564  			"with PM Timer: %ldms instead of 100ms\n",
565  			(long)res);
566  		/* Correct the lapic counter value */
567  		res = (((u64)(*delta)) * pm_100ms);
568  		do_div(res, deltapm);
569  		pr_info("APIC delta adjusted to PM-Timer: "
570  			"%lu (%ld)\n", (unsigned long)res, *delta);
571  		*delta = (long)res;
572  	}
573  
574  	return 0;
575  }
576  
calibrate_APIC_clock(void)577  static int __init calibrate_APIC_clock(void)
578  {
579  	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
580  	void (*real_handler)(struct clock_event_device *dev);
581  	unsigned long deltaj;
582  	long delta;
583  	int pm_referenced = 0;
584  
585  	local_irq_disable();
586  
587  	/* Replace the global interrupt handler */
588  	real_handler = global_clock_event->event_handler;
589  	global_clock_event->event_handler = lapic_cal_handler;
590  
591  	/*
592  	 * Setup the APIC counter to maximum. There is no way the lapic
593  	 * can underflow in the 100ms detection time frame
594  	 */
595  	__setup_APIC_LVTT(0xffffffff, 0, 0);
596  
597  	/* Let the interrupts run */
598  	local_irq_enable();
599  
600  	while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
601  		cpu_relax();
602  
603  	local_irq_disable();
604  
605  	/* Restore the real event handler */
606  	global_clock_event->event_handler = real_handler;
607  
608  	/* Build delta t1-t2 as apic timer counts down */
609  	delta = lapic_cal_t1 - lapic_cal_t2;
610  	apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
611  
612  	/* we trust the PM based calibration if possible */
613  	pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
614  					&delta);
615  
616  	/* Calculate the scaled math multiplication factor */
617  	lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
618  				       lapic_clockevent.shift);
619  	lapic_clockevent.max_delta_ns =
620  		clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
621  	lapic_clockevent.min_delta_ns =
622  		clockevent_delta2ns(0xF, &lapic_clockevent);
623  
624  	calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
625  
626  	apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
627  	apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
628  	apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
629  		    calibration_result);
630  
631  	if (cpu_has_tsc) {
632  		delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
633  		apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
634  			    "%ld.%04ld MHz.\n",
635  			    (delta / LAPIC_CAL_LOOPS) / (1000000 / HZ),
636  			    (delta / LAPIC_CAL_LOOPS) % (1000000 / HZ));
637  	}
638  
639  	apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
640  		    "%u.%04u MHz.\n",
641  		    calibration_result / (1000000 / HZ),
642  		    calibration_result % (1000000 / HZ));
643  
644  	/*
645  	 * Do a sanity check on the APIC calibration result
646  	 */
647  	if (calibration_result < (1000000 / HZ)) {
648  		local_irq_enable();
649  		pr_warning("APIC frequency too slow, disabling apic timer\n");
650  		return -1;
651  	}
652  
653  	levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
654  
655  	/*
656  	 * PM timer calibration failed or not turned on
657  	 * so lets try APIC timer based calibration
658  	 */
659  	if (!pm_referenced) {
660  		apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
661  
662  		/*
663  		 * Setup the apic timer manually
664  		 */
665  		levt->event_handler = lapic_cal_handler;
666  		lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
667  		lapic_cal_loops = -1;
668  
669  		/* Let the interrupts run */
670  		local_irq_enable();
671  
672  		while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
673  			cpu_relax();
674  
675  		/* Stop the lapic timer */
676  		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
677  
678  		/* Jiffies delta */
679  		deltaj = lapic_cal_j2 - lapic_cal_j1;
680  		apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
681  
682  		/* Check, if the jiffies result is consistent */
683  		if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
684  			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
685  		else
686  			levt->features |= CLOCK_EVT_FEAT_DUMMY;
687  	} else
688  		local_irq_enable();
689  
690  	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
691  		pr_warning("APIC timer disabled due to verification failure\n");
692  			return -1;
693  	}
694  
695  	return 0;
696  }
697  
698  /*
699   * Setup the boot APIC
700   *
701   * Calibrate and verify the result.
702   */
setup_boot_APIC_clock(void)703  void __init setup_boot_APIC_clock(void)
704  {
705  	/*
706  	 * The local apic timer can be disabled via the kernel
707  	 * commandline or from the CPU detection code. Register the lapic
708  	 * timer as a dummy clock event source on SMP systems, so the
709  	 * broadcast mechanism is used. On UP systems simply ignore it.
710  	 */
711  	if (disable_apic_timer) {
712  		pr_info("Disabling APIC timer\n");
713  		/* No broadcast on UP ! */
714  		if (num_possible_cpus() > 1) {
715  			lapic_clockevent.mult = 1;
716  			setup_APIC_timer();
717  		}
718  		return;
719  	}
720  
721  	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
722  		    "calibrating APIC timer ...\n");
723  
724  	if (calibrate_APIC_clock()) {
725  		/* No broadcast on UP ! */
726  		if (num_possible_cpus() > 1)
727  			setup_APIC_timer();
728  		return;
729  	}
730  
731  	/*
732  	 * If nmi_watchdog is set to IO_APIC, we need the
733  	 * PIT/HPET going.  Otherwise register lapic as a dummy
734  	 * device.
735  	 */
736  	if (nmi_watchdog != NMI_IO_APIC)
737  		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
738  	else
739  		pr_warning("APIC timer registered as dummy,"
740  			" due to nmi_watchdog=%d!\n", nmi_watchdog);
741  
742  	/* Setup the lapic or request the broadcast */
743  	setup_APIC_timer();
744  }
745  
setup_secondary_APIC_clock(void)746  void __cpuinit setup_secondary_APIC_clock(void)
747  {
748  	setup_APIC_timer();
749  }
750  
751  /*
752   * The guts of the apic timer interrupt
753   */
local_apic_timer_interrupt(void)754  static void local_apic_timer_interrupt(void)
755  {
756  	int cpu = smp_processor_id();
757  	struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
758  
759  	/*
760  	 * Normally we should not be here till LAPIC has been initialized but
761  	 * in some cases like kdump, its possible that there is a pending LAPIC
762  	 * timer interrupt from previous kernel's context and is delivered in
763  	 * new kernel the moment interrupts are enabled.
764  	 *
765  	 * Interrupts are enabled early and LAPIC is setup much later, hence
766  	 * its possible that when we get here evt->event_handler is NULL.
767  	 * Check for event_handler being NULL and discard the interrupt as
768  	 * spurious.
769  	 */
770  	if (!evt->event_handler) {
771  		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
772  		/* Switch it off */
773  		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
774  		return;
775  	}
776  
777  	/*
778  	 * the NMI deadlock-detector uses this.
779  	 */
780  	inc_irq_stat(apic_timer_irqs);
781  
782  	evt->event_handler(evt);
783  }
784  
785  /*
786   * Local APIC timer interrupt. This is the most natural way for doing
787   * local interrupts, but local timer interrupts can be emulated by
788   * broadcast interrupts too. [in case the hw doesn't support APIC timers]
789   *
790   * [ if a single-CPU system runs an SMP kernel then we call the local
791   *   interrupt as well. Thus we cannot inline the local irq ... ]
792   */
smp_apic_timer_interrupt(struct pt_regs * regs)793  void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
794  {
795  	struct pt_regs *old_regs = set_irq_regs(regs);
796  
797  	/*
798  	 * NOTE! We'd better ACK the irq immediately,
799  	 * because timer handling can be slow.
800  	 */
801  	ack_APIC_irq();
802  	/*
803  	 * update_process_times() expects us to have done irq_enter().
804  	 * Besides, if we don't timer interrupts ignore the global
805  	 * interrupt lock, which is the WrongThing (tm) to do.
806  	 */
807  	exit_idle();
808  	irq_enter();
809  	local_apic_timer_interrupt();
810  	irq_exit();
811  
812  	set_irq_regs(old_regs);
813  }
814  
setup_profiling_timer(unsigned int multiplier)815  int setup_profiling_timer(unsigned int multiplier)
816  {
817  	return -EINVAL;
818  }
819  
820  /*
821   * Local APIC start and shutdown
822   */
823  
824  /**
825   * clear_local_APIC - shutdown the local APIC
826   *
827   * This is called, when a CPU is disabled and before rebooting, so the state of
828   * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
829   * leftovers during boot.
830   */
clear_local_APIC(void)831  void clear_local_APIC(void)
832  {
833  	int maxlvt;
834  	u32 v;
835  
836  	/* APIC hasn't been mapped yet */
837  	if (!apic_phys)
838  		return;
839  
840  	maxlvt = lapic_get_maxlvt();
841  	/*
842  	 * Masking an LVT entry can trigger a local APIC error
843  	 * if the vector is zero. Mask LVTERR first to prevent this.
844  	 */
845  	if (maxlvt >= 3) {
846  		v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
847  		apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
848  	}
849  	/*
850  	 * Careful: we have to set masks only first to deassert
851  	 * any level-triggered sources.
852  	 */
853  	v = apic_read(APIC_LVTT);
854  	apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
855  	v = apic_read(APIC_LVT0);
856  	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
857  	v = apic_read(APIC_LVT1);
858  	apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
859  	if (maxlvt >= 4) {
860  		v = apic_read(APIC_LVTPC);
861  		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
862  	}
863  
864  	/* lets not touch this if we didn't frob it */
865  #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
866  	if (maxlvt >= 5) {
867  		v = apic_read(APIC_LVTTHMR);
868  		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
869  	}
870  #endif
871  	/*
872  	 * Clean APIC state for other OSs:
873  	 */
874  	apic_write(APIC_LVTT, APIC_LVT_MASKED);
875  	apic_write(APIC_LVT0, APIC_LVT_MASKED);
876  	apic_write(APIC_LVT1, APIC_LVT_MASKED);
877  	if (maxlvt >= 3)
878  		apic_write(APIC_LVTERR, APIC_LVT_MASKED);
879  	if (maxlvt >= 4)
880  		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
881  
882  	/* Integrated APIC (!82489DX) ? */
883  	if (lapic_is_integrated()) {
884  		if (maxlvt > 3)
885  			/* Clear ESR due to Pentium errata 3AP and 11AP */
886  			apic_write(APIC_ESR, 0);
887  		apic_read(APIC_ESR);
888  	}
889  }
890  
891  /**
892   * disable_local_APIC - clear and disable the local APIC
893   */
disable_local_APIC(void)894  void disable_local_APIC(void)
895  {
896  	unsigned int value;
897  
898  	/* APIC hasn't been mapped yet */
899  	if (!apic_phys)
900  		return;
901  
902  	clear_local_APIC();
903  
904  	/*
905  	 * Disable APIC (implies clearing of registers
906  	 * for 82489DX!).
907  	 */
908  	value = apic_read(APIC_SPIV);
909  	value &= ~APIC_SPIV_APIC_ENABLED;
910  	apic_write(APIC_SPIV, value);
911  
912  #ifdef CONFIG_X86_32
913  	/*
914  	 * When LAPIC was disabled by the BIOS and enabled by the kernel,
915  	 * restore the disabled state.
916  	 */
917  	if (enabled_via_apicbase) {
918  		unsigned int l, h;
919  
920  		rdmsr(MSR_IA32_APICBASE, l, h);
921  		l &= ~MSR_IA32_APICBASE_ENABLE;
922  		wrmsr(MSR_IA32_APICBASE, l, h);
923  	}
924  #endif
925  }
926  
927  /*
928   * If Linux enabled the LAPIC against the BIOS default disable it down before
929   * re-entering the BIOS on shutdown.  Otherwise the BIOS may get confused and
930   * not power-off.  Additionally clear all LVT entries before disable_local_APIC
931   * for the case where Linux didn't enable the LAPIC.
932   */
lapic_shutdown(void)933  void lapic_shutdown(void)
934  {
935  	unsigned long flags;
936  
937  	if (!cpu_has_apic)
938  		return;
939  
940  	local_irq_save(flags);
941  
942  #ifdef CONFIG_X86_32
943  	if (!enabled_via_apicbase)
944  		clear_local_APIC();
945  	else
946  #endif
947  		disable_local_APIC();
948  
949  
950  	local_irq_restore(flags);
951  }
952  
953  /*
954   * This is to verify that we're looking at a real local APIC.
955   * Check these against your board if the CPUs aren't getting
956   * started for no apparent reason.
957   */
verify_local_APIC(void)958  int __init verify_local_APIC(void)
959  {
960  	unsigned int reg0, reg1;
961  
962  	/*
963  	 * The version register is read-only in a real APIC.
964  	 */
965  	reg0 = apic_read(APIC_LVR);
966  	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
967  	apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
968  	reg1 = apic_read(APIC_LVR);
969  	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
970  
971  	/*
972  	 * The two version reads above should print the same
973  	 * numbers.  If the second one is different, then we
974  	 * poke at a non-APIC.
975  	 */
976  	if (reg1 != reg0)
977  		return 0;
978  
979  	/*
980  	 * Check if the version looks reasonably.
981  	 */
982  	reg1 = GET_APIC_VERSION(reg0);
983  	if (reg1 == 0x00 || reg1 == 0xff)
984  		return 0;
985  	reg1 = lapic_get_maxlvt();
986  	if (reg1 < 0x02 || reg1 == 0xff)
987  		return 0;
988  
989  	/*
990  	 * The ID register is read/write in a real APIC.
991  	 */
992  	reg0 = apic_read(APIC_ID);
993  	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
994  	apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
995  	reg1 = apic_read(APIC_ID);
996  	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
997  	apic_write(APIC_ID, reg0);
998  	if (reg1 != (reg0 ^ APIC_ID_MASK))
999  		return 0;
1000  
1001  	/*
1002  	 * The next two are just to see if we have sane values.
1003  	 * They're only really relevant if we're in Virtual Wire
1004  	 * compatibility mode, but most boxes are anymore.
1005  	 */
1006  	reg0 = apic_read(APIC_LVT0);
1007  	apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
1008  	reg1 = apic_read(APIC_LVT1);
1009  	apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
1010  
1011  	return 1;
1012  }
1013  
1014  /**
1015   * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1016   */
sync_Arb_IDs(void)1017  void __init sync_Arb_IDs(void)
1018  {
1019  	/*
1020  	 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1021  	 * needed on AMD.
1022  	 */
1023  	if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1024  		return;
1025  
1026  	/*
1027  	 * Wait for idle.
1028  	 */
1029  	apic_wait_icr_idle();
1030  
1031  	apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1032  	apic_write(APIC_ICR, APIC_DEST_ALLINC |
1033  			APIC_INT_LEVELTRIG | APIC_DM_INIT);
1034  }
1035  
1036  /*
1037   * An initial setup of the virtual wire mode.
1038   */
init_bsp_APIC(void)1039  void __init init_bsp_APIC(void)
1040  {
1041  	unsigned int value;
1042  
1043  	/*
1044  	 * Don't do the setup now if we have a SMP BIOS as the
1045  	 * through-I/O-APIC virtual wire mode might be active.
1046  	 */
1047  	if (smp_found_config || !cpu_has_apic)
1048  		return;
1049  
1050  	/*
1051  	 * Do not trust the local APIC being empty at bootup.
1052  	 */
1053  	clear_local_APIC();
1054  
1055  	/*
1056  	 * Enable APIC.
1057  	 */
1058  	value = apic_read(APIC_SPIV);
1059  	value &= ~APIC_VECTOR_MASK;
1060  	value |= APIC_SPIV_APIC_ENABLED;
1061  
1062  #ifdef CONFIG_X86_32
1063  	/* This bit is reserved on P4/Xeon and should be cleared */
1064  	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1065  	    (boot_cpu_data.x86 == 15))
1066  		value &= ~APIC_SPIV_FOCUS_DISABLED;
1067  	else
1068  #endif
1069  		value |= APIC_SPIV_FOCUS_DISABLED;
1070  	value |= SPURIOUS_APIC_VECTOR;
1071  	apic_write(APIC_SPIV, value);
1072  
1073  	/*
1074  	 * Set up the virtual wire mode.
1075  	 */
1076  	apic_write(APIC_LVT0, APIC_DM_EXTINT);
1077  	value = APIC_DM_NMI;
1078  	if (!lapic_is_integrated())		/* 82489DX */
1079  		value |= APIC_LVT_LEVEL_TRIGGER;
1080  	apic_write(APIC_LVT1, value);
1081  }
1082  
lapic_setup_esr(void)1083  static void __cpuinit lapic_setup_esr(void)
1084  {
1085  	unsigned int oldvalue, value, maxlvt;
1086  
1087  	if (!lapic_is_integrated()) {
1088  		pr_info("No ESR for 82489DX.\n");
1089  		return;
1090  	}
1091  
1092  	if (esr_disable) {
1093  		/*
1094  		 * Something untraceable is creating bad interrupts on
1095  		 * secondary quads ... for the moment, just leave the
1096  		 * ESR disabled - we can't do anything useful with the
1097  		 * errors anyway - mbligh
1098  		 */
1099  		pr_info("Leaving ESR disabled.\n");
1100  		return;
1101  	}
1102  
1103  	maxlvt = lapic_get_maxlvt();
1104  	if (maxlvt > 3)		/* Due to the Pentium erratum 3AP. */
1105  		apic_write(APIC_ESR, 0);
1106  	oldvalue = apic_read(APIC_ESR);
1107  
1108  	/* enables sending errors */
1109  	value = ERROR_APIC_VECTOR;
1110  	apic_write(APIC_LVTERR, value);
1111  
1112  	/*
1113  	 * spec says clear errors after enabling vector.
1114  	 */
1115  	if (maxlvt > 3)
1116  		apic_write(APIC_ESR, 0);
1117  	value = apic_read(APIC_ESR);
1118  	if (value != oldvalue)
1119  		apic_printk(APIC_VERBOSE, "ESR value before enabling "
1120  			"vector: 0x%08x  after: 0x%08x\n",
1121  			oldvalue, value);
1122  }
1123  
1124  
1125  /**
1126   * setup_local_APIC - setup the local APIC
1127   */
setup_local_APIC(void)1128  void __cpuinit setup_local_APIC(void)
1129  {
1130  	unsigned int value;
1131  	int i, j;
1132  
1133  #ifdef CONFIG_X86_32
1134  	/* Pound the ESR really hard over the head with a big hammer - mbligh */
1135  	if (lapic_is_integrated() && esr_disable) {
1136  		apic_write(APIC_ESR, 0);
1137  		apic_write(APIC_ESR, 0);
1138  		apic_write(APIC_ESR, 0);
1139  		apic_write(APIC_ESR, 0);
1140  	}
1141  #endif
1142  
1143  	preempt_disable();
1144  
1145  	/*
1146  	 * Double-check whether this APIC is really registered.
1147  	 * This is meaningless in clustered apic mode, so we skip it.
1148  	 */
1149  	if (!apic_id_registered())
1150  		BUG();
1151  
1152  	/*
1153  	 * Intel recommends to set DFR, LDR and TPR before enabling
1154  	 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
1155  	 * document number 292116).  So here it goes...
1156  	 */
1157  	init_apic_ldr();
1158  
1159  	/*
1160  	 * Set Task Priority to 'accept all'. We never change this
1161  	 * later on.
1162  	 */
1163  	value = apic_read(APIC_TASKPRI);
1164  	value &= ~APIC_TPRI_MASK;
1165  	apic_write(APIC_TASKPRI, value);
1166  
1167  	/*
1168  	 * After a crash, we no longer service the interrupts and a pending
1169  	 * interrupt from previous kernel might still have ISR bit set.
1170  	 *
1171  	 * Most probably by now CPU has serviced that pending interrupt and
1172  	 * it might not have done the ack_APIC_irq() because it thought,
1173  	 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1174  	 * does not clear the ISR bit and cpu thinks it has already serivced
1175  	 * the interrupt. Hence a vector might get locked. It was noticed
1176  	 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1177  	 */
1178  	for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1179  		value = apic_read(APIC_ISR + i*0x10);
1180  		for (j = 31; j >= 0; j--) {
1181  			if (value & (1<<j))
1182  				ack_APIC_irq();
1183  		}
1184  	}
1185  
1186  	/*
1187  	 * Now that we are all set up, enable the APIC
1188  	 */
1189  	value = apic_read(APIC_SPIV);
1190  	value &= ~APIC_VECTOR_MASK;
1191  	/*
1192  	 * Enable APIC
1193  	 */
1194  	value |= APIC_SPIV_APIC_ENABLED;
1195  
1196  #ifdef CONFIG_X86_32
1197  	/*
1198  	 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1199  	 * certain networking cards. If high frequency interrupts are
1200  	 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1201  	 * entry is masked/unmasked at a high rate as well then sooner or
1202  	 * later IOAPIC line gets 'stuck', no more interrupts are received
1203  	 * from the device. If focus CPU is disabled then the hang goes
1204  	 * away, oh well :-(
1205  	 *
1206  	 * [ This bug can be reproduced easily with a level-triggered
1207  	 *   PCI Ne2000 networking cards and PII/PIII processors, dual
1208  	 *   BX chipset. ]
1209  	 */
1210  	/*
1211  	 * Actually disabling the focus CPU check just makes the hang less
1212  	 * frequent as it makes the interrupt distributon model be more
1213  	 * like LRU than MRU (the short-term load is more even across CPUs).
1214  	 * See also the comment in end_level_ioapic_irq().  --macro
1215  	 */
1216  
1217  	/*
1218  	 * - enable focus processor (bit==0)
1219  	 * - 64bit mode always use processor focus
1220  	 *   so no need to set it
1221  	 */
1222  	value &= ~APIC_SPIV_FOCUS_DISABLED;
1223  #endif
1224  
1225  	/*
1226  	 * Set spurious IRQ vector
1227  	 */
1228  	value |= SPURIOUS_APIC_VECTOR;
1229  	apic_write(APIC_SPIV, value);
1230  
1231  	/*
1232  	 * Set up LVT0, LVT1:
1233  	 *
1234  	 * set up through-local-APIC on the BP's LINT0. This is not
1235  	 * strictly necessary in pure symmetric-IO mode, but sometimes
1236  	 * we delegate interrupts to the 8259A.
1237  	 */
1238  	/*
1239  	 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1240  	 */
1241  	value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1242  	if (!smp_processor_id() && (pic_mode || !value)) {
1243  		value = APIC_DM_EXTINT;
1244  		apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1245  				smp_processor_id());
1246  	} else {
1247  		value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1248  		apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1249  				smp_processor_id());
1250  	}
1251  	apic_write(APIC_LVT0, value);
1252  
1253  	/*
1254  	 * only the BP should see the LINT1 NMI signal, obviously.
1255  	 */
1256  	if (!smp_processor_id())
1257  		value = APIC_DM_NMI;
1258  	else
1259  		value = APIC_DM_NMI | APIC_LVT_MASKED;
1260  	if (!lapic_is_integrated())		/* 82489DX */
1261  		value |= APIC_LVT_LEVEL_TRIGGER;
1262  	apic_write(APIC_LVT1, value);
1263  
1264  	preempt_enable();
1265  }
1266  
end_local_APIC_setup(void)1267  void __cpuinit end_local_APIC_setup(void)
1268  {
1269  	lapic_setup_esr();
1270  
1271  #ifdef CONFIG_X86_32
1272  	{
1273  		unsigned int value;
1274  		/* Disable the local apic timer */
1275  		value = apic_read(APIC_LVTT);
1276  		value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1277  		apic_write(APIC_LVTT, value);
1278  	}
1279  #endif
1280  
1281  	setup_apic_nmi_watchdog(NULL);
1282  	apic_pm_activate();
1283  }
1284  
1285  #ifdef HAVE_X2APIC
check_x2apic(void)1286  void check_x2apic(void)
1287  {
1288  	int msr, msr2;
1289  
1290  	rdmsr(MSR_IA32_APICBASE, msr, msr2);
1291  
1292  	if (msr & X2APIC_ENABLE) {
1293  		pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
1294  		x2apic_preenabled = x2apic = 1;
1295  		apic_ops = &x2apic_ops;
1296  	}
1297  }
1298  
enable_x2apic(void)1299  void enable_x2apic(void)
1300  {
1301  	int msr, msr2;
1302  
1303  	rdmsr(MSR_IA32_APICBASE, msr, msr2);
1304  	if (!(msr & X2APIC_ENABLE)) {
1305  		pr_info("Enabling x2apic\n");
1306  		wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1307  	}
1308  }
1309  
enable_IR_x2apic(void)1310  void __init enable_IR_x2apic(void)
1311  {
1312  #ifdef CONFIG_INTR_REMAP
1313  	int ret;
1314  	unsigned long flags;
1315  
1316  	if (!cpu_has_x2apic)
1317  		return;
1318  
1319  	if (!x2apic_preenabled && disable_x2apic) {
1320  		pr_info("Skipped enabling x2apic and Interrupt-remapping "
1321  			"because of nox2apic\n");
1322  		return;
1323  	}
1324  
1325  	if (x2apic_preenabled && disable_x2apic)
1326  		panic("Bios already enabled x2apic, can't enforce nox2apic");
1327  
1328  	if (!x2apic_preenabled && skip_ioapic_setup) {
1329  		pr_info("Skipped enabling x2apic and Interrupt-remapping "
1330  			"because of skipping io-apic setup\n");
1331  		return;
1332  	}
1333  
1334  	ret = dmar_table_init();
1335  	if (ret) {
1336  		pr_info("dmar_table_init() failed with %d:\n", ret);
1337  
1338  		if (x2apic_preenabled)
1339  			panic("x2apic enabled by bios. But IR enabling failed");
1340  		else
1341  			pr_info("Not enabling x2apic,Intr-remapping\n");
1342  		return;
1343  	}
1344  
1345  	local_irq_save(flags);
1346  	mask_8259A();
1347  
1348  	ret = save_mask_IO_APIC_setup();
1349  	if (ret) {
1350  		pr_info("Saving IO-APIC state failed: %d\n", ret);
1351  		goto end;
1352  	}
1353  
1354  	ret = enable_intr_remapping(1);
1355  
1356  	if (ret && x2apic_preenabled) {
1357  		local_irq_restore(flags);
1358  		panic("x2apic enabled by bios. But IR enabling failed");
1359  	}
1360  
1361  	if (ret)
1362  		goto end_restore;
1363  
1364  	if (!x2apic) {
1365  		x2apic = 1;
1366  		apic_ops = &x2apic_ops;
1367  		enable_x2apic();
1368  	}
1369  
1370  end_restore:
1371  	if (ret)
1372  		/*
1373  		 * IR enabling failed
1374  		 */
1375  		restore_IO_APIC_setup();
1376  	else
1377  		reinit_intr_remapped_IO_APIC(x2apic_preenabled);
1378  
1379  end:
1380  	unmask_8259A();
1381  	local_irq_restore(flags);
1382  
1383  	if (!ret) {
1384  		if (!x2apic_preenabled)
1385  			pr_info("Enabled x2apic and interrupt-remapping\n");
1386  		else
1387  			pr_info("Enabled Interrupt-remapping\n");
1388  	} else
1389  		pr_err("Failed to enable Interrupt-remapping and x2apic\n");
1390  #else
1391  	if (!cpu_has_x2apic)
1392  		return;
1393  
1394  	if (x2apic_preenabled)
1395  		panic("x2apic enabled prior OS handover,"
1396  		      " enable CONFIG_INTR_REMAP");
1397  
1398  	pr_info("Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1399  		" and x2apic\n");
1400  #endif
1401  
1402  	return;
1403  }
1404  #endif /* HAVE_X2APIC */
1405  
1406  #ifdef CONFIG_X86_64
1407  /*
1408   * Detect and enable local APICs on non-SMP boards.
1409   * Original code written by Keir Fraser.
1410   * On AMD64 we trust the BIOS - if it says no APIC it is likely
1411   * not correctly set up (usually the APIC timer won't work etc.)
1412   */
detect_init_APIC(void)1413  static int __init detect_init_APIC(void)
1414  {
1415  	if (!cpu_has_apic) {
1416  		pr_info("No local APIC present\n");
1417  		return -1;
1418  	}
1419  
1420  	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1421  	boot_cpu_physical_apicid = 0;
1422  	return 0;
1423  }
1424  #else
1425  /*
1426   * Detect and initialize APIC
1427   */
detect_init_APIC(void)1428  static int __init detect_init_APIC(void)
1429  {
1430  	u32 h, l, features;
1431  
1432  	/* Disabled by kernel option? */
1433  	if (disable_apic)
1434  		return -1;
1435  
1436  	switch (boot_cpu_data.x86_vendor) {
1437  	case X86_VENDOR_AMD:
1438  		if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1439  		    (boot_cpu_data.x86 >= 15))
1440  			break;
1441  		goto no_apic;
1442  	case X86_VENDOR_INTEL:
1443  		if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1444  		    (boot_cpu_data.x86 == 5 && cpu_has_apic))
1445  			break;
1446  		goto no_apic;
1447  	default:
1448  		goto no_apic;
1449  	}
1450  
1451  	if (!cpu_has_apic) {
1452  		/*
1453  		 * Over-ride BIOS and try to enable the local APIC only if
1454  		 * "lapic" specified.
1455  		 */
1456  		if (!force_enable_local_apic) {
1457  			pr_info("Local APIC disabled by BIOS -- "
1458  				"you can enable it with \"lapic\"\n");
1459  			return -1;
1460  		}
1461  		/*
1462  		 * Some BIOSes disable the local APIC in the APIC_BASE
1463  		 * MSR. This can only be done in software for Intel P6 or later
1464  		 * and AMD K7 (Model > 1) or later.
1465  		 */
1466  		rdmsr(MSR_IA32_APICBASE, l, h);
1467  		if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1468  			pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1469  			l &= ~MSR_IA32_APICBASE_BASE;
1470  			l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
1471  			wrmsr(MSR_IA32_APICBASE, l, h);
1472  			enabled_via_apicbase = 1;
1473  		}
1474  	}
1475  	/*
1476  	 * The APIC feature bit should now be enabled
1477  	 * in `cpuid'
1478  	 */
1479  	features = cpuid_edx(1);
1480  	if (!(features & (1 << X86_FEATURE_APIC))) {
1481  		pr_warning("Could not enable APIC!\n");
1482  		return -1;
1483  	}
1484  	set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1485  	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1486  
1487  	/* The BIOS may have set up the APIC at some other address */
1488  	rdmsr(MSR_IA32_APICBASE, l, h);
1489  	if (l & MSR_IA32_APICBASE_ENABLE)
1490  		mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1491  
1492  	pr_info("Found and enabled local APIC!\n");
1493  
1494  	apic_pm_activate();
1495  
1496  	return 0;
1497  
1498  no_apic:
1499  	pr_info("No local APIC present or hardware disabled\n");
1500  	return -1;
1501  }
1502  #endif
1503  
1504  #ifdef CONFIG_X86_64
early_init_lapic_mapping(void)1505  void __init early_init_lapic_mapping(void)
1506  {
1507  	unsigned long phys_addr;
1508  
1509  	/*
1510  	 * If no local APIC can be found then go out
1511  	 * : it means there is no mpatable and MADT
1512  	 */
1513  	if (!smp_found_config)
1514  		return;
1515  
1516  	phys_addr = mp_lapic_addr;
1517  
1518  	set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1519  	apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1520  		    APIC_BASE, phys_addr);
1521  
1522  	/*
1523  	 * Fetch the APIC ID of the BSP in case we have a
1524  	 * default configuration (or the MP table is broken).
1525  	 */
1526  	boot_cpu_physical_apicid = read_apic_id();
1527  }
1528  #endif
1529  
1530  /**
1531   * init_apic_mappings - initialize APIC mappings
1532   */
init_apic_mappings(void)1533  void __init init_apic_mappings(void)
1534  {
1535  #ifdef HAVE_X2APIC
1536  	if (x2apic) {
1537  		boot_cpu_physical_apicid = read_apic_id();
1538  		return;
1539  	}
1540  #endif
1541  
1542  	/*
1543  	 * If no local APIC can be found then set up a fake all
1544  	 * zeroes page to simulate the local APIC and another
1545  	 * one for the IO-APIC.
1546  	 */
1547  	if (!smp_found_config && detect_init_APIC()) {
1548  		apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
1549  		apic_phys = __pa(apic_phys);
1550  	} else
1551  		apic_phys = mp_lapic_addr;
1552  
1553  	set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1554  	apic_printk(APIC_VERBOSE, "mapped APIC to %08lx (%08lx)\n",
1555  				APIC_BASE, apic_phys);
1556  
1557  	/*
1558  	 * Fetch the APIC ID of the BSP in case we have a
1559  	 * default configuration (or the MP table is broken).
1560  	 */
1561  	if (boot_cpu_physical_apicid == -1U)
1562  		boot_cpu_physical_apicid = read_apic_id();
1563  }
1564  
1565  /*
1566   * This initializes the IO-APIC and APIC hardware if this is
1567   * a UP kernel.
1568   */
1569  int apic_version[MAX_APICS];
1570  
APIC_init_uniprocessor(void)1571  int __init APIC_init_uniprocessor(void)
1572  {
1573  #ifdef CONFIG_X86_64
1574  	if (disable_apic) {
1575  		pr_info("Apic disabled\n");
1576  		return -1;
1577  	}
1578  	if (!cpu_has_apic) {
1579  		disable_apic = 1;
1580  		pr_info("Apic disabled by BIOS\n");
1581  		return -1;
1582  	}
1583  #else
1584  	if (!smp_found_config && !cpu_has_apic)
1585  		return -1;
1586  
1587  	/*
1588  	 * Complain if the BIOS pretends there is one.
1589  	 */
1590  	if (!cpu_has_apic &&
1591  	    APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1592  		pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
1593  			boot_cpu_physical_apicid);
1594  		clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1595  		return -1;
1596  	}
1597  #endif
1598  
1599  #ifdef HAVE_X2APIC
1600  	enable_IR_x2apic();
1601  #endif
1602  #ifdef CONFIG_X86_64
1603  	setup_apic_routing();
1604  #endif
1605  
1606  	verify_local_APIC();
1607  	connect_bsp_APIC();
1608  
1609  #ifdef CONFIG_X86_64
1610  	apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1611  #else
1612  	/*
1613  	 * Hack: In case of kdump, after a crash, kernel might be booting
1614  	 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1615  	 * might be zero if read from MP tables. Get it from LAPIC.
1616  	 */
1617  # ifdef CONFIG_CRASH_DUMP
1618  	boot_cpu_physical_apicid = read_apic_id();
1619  # endif
1620  #endif
1621  	physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1622  	setup_local_APIC();
1623  
1624  #ifdef CONFIG_X86_64
1625  	/*
1626  	 * Now enable IO-APICs, actually call clear_IO_APIC
1627  	 * We need clear_IO_APIC before enabling vector on BP
1628  	 */
1629  	if (!skip_ioapic_setup && nr_ioapics)
1630  		enable_IO_APIC();
1631  #endif
1632  
1633  #ifdef CONFIG_X86_IO_APIC
1634  	if (!smp_found_config || skip_ioapic_setup || !nr_ioapics)
1635  #endif
1636  		localise_nmi_watchdog();
1637  	end_local_APIC_setup();
1638  
1639  #ifdef CONFIG_X86_IO_APIC
1640  	if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1641  		setup_IO_APIC();
1642  # ifdef CONFIG_X86_64
1643  	else
1644  		nr_ioapics = 0;
1645  # endif
1646  #endif
1647  
1648  #ifdef CONFIG_X86_64
1649  	setup_boot_APIC_clock();
1650  	check_nmi_watchdog();
1651  #else
1652  	setup_boot_clock();
1653  #endif
1654  
1655  	return 0;
1656  }
1657  
1658  /*
1659   * Local APIC interrupts
1660   */
1661  
1662  /*
1663   * This interrupt should _never_ happen with our APIC/SMP architecture
1664   */
smp_spurious_interrupt(struct pt_regs * regs)1665  void smp_spurious_interrupt(struct pt_regs *regs)
1666  {
1667  	u32 v;
1668  
1669  	exit_idle();
1670  	irq_enter();
1671  	/*
1672  	 * Check if this really is a spurious interrupt and ACK it
1673  	 * if it is a vectored one.  Just in case...
1674  	 * Spurious interrupts should not be ACKed.
1675  	 */
1676  	v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1677  	if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1678  		ack_APIC_irq();
1679  
1680  	inc_irq_stat(irq_spurious_count);
1681  
1682  	/* see sw-dev-man vol 3, chapter 7.4.13.5 */
1683  	pr_info("spurious APIC interrupt on CPU#%d, "
1684  		"should never happen.\n", smp_processor_id());
1685  	irq_exit();
1686  }
1687  
1688  /*
1689   * This interrupt should never happen with our APIC/SMP architecture
1690   */
smp_error_interrupt(struct pt_regs * regs)1691  void smp_error_interrupt(struct pt_regs *regs)
1692  {
1693  	u32 v, v1;
1694  
1695  	exit_idle();
1696  	irq_enter();
1697  	/* First tickle the hardware, only then report what went on. -- REW */
1698  	v = apic_read(APIC_ESR);
1699  	apic_write(APIC_ESR, 0);
1700  	v1 = apic_read(APIC_ESR);
1701  	ack_APIC_irq();
1702  	atomic_inc(&irq_err_count);
1703  
1704  	/*
1705  	 * Here is what the APIC error bits mean:
1706  	 * 0: Send CS error
1707  	 * 1: Receive CS error
1708  	 * 2: Send accept error
1709  	 * 3: Receive accept error
1710  	 * 4: Reserved
1711  	 * 5: Send illegal vector
1712  	 * 6: Received illegal vector
1713  	 * 7: Illegal register address
1714  	 */
1715  	pr_debug("APIC error on CPU%d: %02x(%02x)\n",
1716  		smp_processor_id(), v , v1);
1717  	irq_exit();
1718  }
1719  
1720  /**
1721   * connect_bsp_APIC - attach the APIC to the interrupt system
1722   */
connect_bsp_APIC(void)1723  void __init connect_bsp_APIC(void)
1724  {
1725  #ifdef CONFIG_X86_32
1726  	if (pic_mode) {
1727  		/*
1728  		 * Do not trust the local APIC being empty at bootup.
1729  		 */
1730  		clear_local_APIC();
1731  		/*
1732  		 * PIC mode, enable APIC mode in the IMCR, i.e.  connect BSP's
1733  		 * local APIC to INT and NMI lines.
1734  		 */
1735  		apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1736  				"enabling APIC mode.\n");
1737  		outb(0x70, 0x22);
1738  		outb(0x01, 0x23);
1739  	}
1740  #endif
1741  	enable_apic_mode();
1742  }
1743  
1744  /**
1745   * disconnect_bsp_APIC - detach the APIC from the interrupt system
1746   * @virt_wire_setup:	indicates, whether virtual wire mode is selected
1747   *
1748   * Virtual wire mode is necessary to deliver legacy interrupts even when the
1749   * APIC is disabled.
1750   */
disconnect_bsp_APIC(int virt_wire_setup)1751  void disconnect_bsp_APIC(int virt_wire_setup)
1752  {
1753  	unsigned int value;
1754  
1755  #ifdef CONFIG_X86_32
1756  	if (pic_mode) {
1757  		/*
1758  		 * Put the board back into PIC mode (has an effect only on
1759  		 * certain older boards).  Note that APIC interrupts, including
1760  		 * IPIs, won't work beyond this point!  The only exception are
1761  		 * INIT IPIs.
1762  		 */
1763  		apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1764  				"entering PIC mode.\n");
1765  		outb(0x70, 0x22);
1766  		outb(0x00, 0x23);
1767  		return;
1768  	}
1769  #endif
1770  
1771  	/* Go back to Virtual Wire compatibility mode */
1772  
1773  	/* For the spurious interrupt use vector F, and enable it */
1774  	value = apic_read(APIC_SPIV);
1775  	value &= ~APIC_VECTOR_MASK;
1776  	value |= APIC_SPIV_APIC_ENABLED;
1777  	value |= 0xf;
1778  	apic_write(APIC_SPIV, value);
1779  
1780  	if (!virt_wire_setup) {
1781  		/*
1782  		 * For LVT0 make it edge triggered, active high,
1783  		 * external and enabled
1784  		 */
1785  		value = apic_read(APIC_LVT0);
1786  		value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1787  			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1788  			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1789  		value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1790  		value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1791  		apic_write(APIC_LVT0, value);
1792  	} else {
1793  		/* Disable LVT0 */
1794  		apic_write(APIC_LVT0, APIC_LVT_MASKED);
1795  	}
1796  
1797  	/*
1798  	 * For LVT1 make it edge triggered, active high,
1799  	 * nmi and enabled
1800  	 */
1801  	value = apic_read(APIC_LVT1);
1802  	value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1803  			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1804  			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1805  	value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1806  	value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1807  	apic_write(APIC_LVT1, value);
1808  }
1809  
generic_processor_info(int apicid,int version)1810  void __cpuinit generic_processor_info(int apicid, int version)
1811  {
1812  	int cpu;
1813  
1814  	/*
1815  	 * Validate version
1816  	 */
1817  	if (version == 0x0) {
1818  		pr_warning("BIOS bug, APIC version is 0 for CPU#%d! "
1819  			   "fixing up to 0x10. (tell your hw vendor)\n",
1820  				version);
1821  		version = 0x10;
1822  	}
1823  	apic_version[apicid] = version;
1824  
1825  	if (num_processors >= nr_cpu_ids) {
1826  		int max = nr_cpu_ids;
1827  		int thiscpu = max + disabled_cpus;
1828  
1829  		pr_warning(
1830  			"ACPI: NR_CPUS/possible_cpus limit of %i reached."
1831  			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
1832  
1833  		disabled_cpus++;
1834  		return;
1835  	}
1836  
1837  	num_processors++;
1838  	cpu = cpumask_next_zero(-1, cpu_present_mask);
1839  
1840  	if (version != apic_version[boot_cpu_physical_apicid])
1841  		WARN_ONCE(1,
1842  			"ACPI: apic version mismatch, bootcpu: %x cpu %d: %x\n",
1843  			apic_version[boot_cpu_physical_apicid], cpu, version);
1844  
1845  	physid_set(apicid, phys_cpu_present_map);
1846  	if (apicid == boot_cpu_physical_apicid) {
1847  		/*
1848  		 * x86_bios_cpu_apicid is required to have processors listed
1849  		 * in same order as logical cpu numbers. Hence the first
1850  		 * entry is BSP, and so on.
1851  		 */
1852  		cpu = 0;
1853  	}
1854  	if (apicid > max_physical_apicid)
1855  		max_physical_apicid = apicid;
1856  
1857  #ifdef CONFIG_X86_32
1858  	/*
1859  	 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
1860  	 * but we need to work other dependencies like SMP_SUSPEND etc
1861  	 * before this can be done without some confusion.
1862  	 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
1863  	 *       - Ashok Raj <ashok.raj@intel.com>
1864  	 */
1865  	if (max_physical_apicid >= 8) {
1866  		switch (boot_cpu_data.x86_vendor) {
1867  		case X86_VENDOR_INTEL:
1868  			if (!APIC_XAPIC(version)) {
1869  				def_to_bigsmp = 0;
1870  				break;
1871  			}
1872  			/* If P4 and above fall through */
1873  		case X86_VENDOR_AMD:
1874  			def_to_bigsmp = 1;
1875  		}
1876  	}
1877  #endif
1878  
1879  #if defined(CONFIG_X86_SMP) || defined(CONFIG_X86_64)
1880  	/* are we being called early in kernel startup? */
1881  	if (early_per_cpu_ptr(x86_cpu_to_apicid)) {
1882  		u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
1883  		u16 *bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1884  
1885  		cpu_to_apicid[cpu] = apicid;
1886  		bios_cpu_apicid[cpu] = apicid;
1887  	} else {
1888  		per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1889  		per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1890  	}
1891  #endif
1892  
1893  	set_cpu_possible(cpu, true);
1894  	set_cpu_present(cpu, true);
1895  }
1896  
1897  #ifdef CONFIG_X86_64
hard_smp_processor_id(void)1898  int hard_smp_processor_id(void)
1899  {
1900  	return read_apic_id();
1901  }
1902  #endif
1903  
1904  /*
1905   * Power management
1906   */
1907  #ifdef CONFIG_PM
1908  
1909  static struct {
1910  	/*
1911  	 * 'active' is true if the local APIC was enabled by us and
1912  	 * not the BIOS; this signifies that we are also responsible
1913  	 * for disabling it before entering apm/acpi suspend
1914  	 */
1915  	int active;
1916  	/* r/w apic fields */
1917  	unsigned int apic_id;
1918  	unsigned int apic_taskpri;
1919  	unsigned int apic_ldr;
1920  	unsigned int apic_dfr;
1921  	unsigned int apic_spiv;
1922  	unsigned int apic_lvtt;
1923  	unsigned int apic_lvtpc;
1924  	unsigned int apic_lvt0;
1925  	unsigned int apic_lvt1;
1926  	unsigned int apic_lvterr;
1927  	unsigned int apic_tmict;
1928  	unsigned int apic_tdcr;
1929  	unsigned int apic_thmr;
1930  } apic_pm_state;
1931  
lapic_suspend(struct sys_device * dev,pm_message_t state)1932  static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1933  {
1934  	unsigned long flags;
1935  	int maxlvt;
1936  
1937  	if (!apic_pm_state.active)
1938  		return 0;
1939  
1940  	maxlvt = lapic_get_maxlvt();
1941  
1942  	apic_pm_state.apic_id = apic_read(APIC_ID);
1943  	apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1944  	apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1945  	apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1946  	apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1947  	apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1948  	if (maxlvt >= 4)
1949  		apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1950  	apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1951  	apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1952  	apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1953  	apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1954  	apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1955  #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1956  	if (maxlvt >= 5)
1957  		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1958  #endif
1959  
1960  	local_irq_save(flags);
1961  	disable_local_APIC();
1962  	local_irq_restore(flags);
1963  	return 0;
1964  }
1965  
lapic_resume(struct sys_device * dev)1966  static int lapic_resume(struct sys_device *dev)
1967  {
1968  	unsigned int l, h;
1969  	unsigned long flags;
1970  	int maxlvt;
1971  
1972  	if (!apic_pm_state.active)
1973  		return 0;
1974  
1975  	maxlvt = lapic_get_maxlvt();
1976  
1977  	local_irq_save(flags);
1978  
1979  #ifdef HAVE_X2APIC
1980  	if (x2apic)
1981  		enable_x2apic();
1982  	else
1983  #endif
1984  	{
1985  		/*
1986  		 * Make sure the APICBASE points to the right address
1987  		 *
1988  		 * FIXME! This will be wrong if we ever support suspend on
1989  		 * SMP! We'll need to do this as part of the CPU restore!
1990  		 */
1991  		rdmsr(MSR_IA32_APICBASE, l, h);
1992  		l &= ~MSR_IA32_APICBASE_BASE;
1993  		l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
1994  		wrmsr(MSR_IA32_APICBASE, l, h);
1995  	}
1996  
1997  	apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
1998  	apic_write(APIC_ID, apic_pm_state.apic_id);
1999  	apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2000  	apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2001  	apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2002  	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2003  	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2004  	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2005  #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2006  	if (maxlvt >= 5)
2007  		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2008  #endif
2009  	if (maxlvt >= 4)
2010  		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2011  	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2012  	apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2013  	apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2014  	apic_write(APIC_ESR, 0);
2015  	apic_read(APIC_ESR);
2016  	apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2017  	apic_write(APIC_ESR, 0);
2018  	apic_read(APIC_ESR);
2019  
2020  	local_irq_restore(flags);
2021  
2022  	return 0;
2023  }
2024  
2025  /*
2026   * This device has no shutdown method - fully functioning local APICs
2027   * are needed on every CPU up until machine_halt/restart/poweroff.
2028   */
2029  
2030  static struct sysdev_class lapic_sysclass = {
2031  	.name		= "lapic",
2032  	.resume		= lapic_resume,
2033  	.suspend	= lapic_suspend,
2034  };
2035  
2036  static struct sys_device device_lapic = {
2037  	.id	= 0,
2038  	.cls	= &lapic_sysclass,
2039  };
2040  
apic_pm_activate(void)2041  static void __cpuinit apic_pm_activate(void)
2042  {
2043  	apic_pm_state.active = 1;
2044  }
2045  
init_lapic_sysfs(void)2046  static int __init init_lapic_sysfs(void)
2047  {
2048  	int error;
2049  
2050  	if (!cpu_has_apic)
2051  		return 0;
2052  	/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2053  
2054  	error = sysdev_class_register(&lapic_sysclass);
2055  	if (!error)
2056  		error = sysdev_register(&device_lapic);
2057  	return error;
2058  }
2059  device_initcall(init_lapic_sysfs);
2060  
2061  #else	/* CONFIG_PM */
2062  
apic_pm_activate(void)2063  static void apic_pm_activate(void) { }
2064  
2065  #endif	/* CONFIG_PM */
2066  
2067  #ifdef CONFIG_X86_64
2068  /*
2069   * apic_is_clustered_box() -- Check if we can expect good TSC
2070   *
2071   * Thus far, the major user of this is IBM's Summit2 series:
2072   *
2073   * Clustered boxes may have unsynced TSC problems if they are
2074   * multi-chassis. Use available data to take a good guess.
2075   * If in doubt, go HPET.
2076   */
apic_is_clustered_box(void)2077  __cpuinit int apic_is_clustered_box(void)
2078  {
2079  	int i, clusters, zeros;
2080  	unsigned id;
2081  	u16 *bios_cpu_apicid;
2082  	DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2083  
2084  	/*
2085  	 * there is not this kind of box with AMD CPU yet.
2086  	 * Some AMD box with quadcore cpu and 8 sockets apicid
2087  	 * will be [4, 0x23] or [8, 0x27] could be thought to
2088  	 * vsmp box still need checking...
2089  	 */
2090  	if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
2091  		return 0;
2092  
2093  	bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2094  	bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2095  
2096  	for (i = 0; i < nr_cpu_ids; i++) {
2097  		/* are we being called early in kernel startup? */
2098  		if (bios_cpu_apicid) {
2099  			id = bios_cpu_apicid[i];
2100  		} else if (i < nr_cpu_ids) {
2101  			if (cpu_present(i))
2102  				id = per_cpu(x86_bios_cpu_apicid, i);
2103  			else
2104  				continue;
2105  		} else
2106  			break;
2107  
2108  		if (id != BAD_APICID)
2109  			__set_bit(APIC_CLUSTERID(id), clustermap);
2110  	}
2111  
2112  	/* Problem:  Partially populated chassis may not have CPUs in some of
2113  	 * the APIC clusters they have been allocated.  Only present CPUs have
2114  	 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2115  	 * Since clusters are allocated sequentially, count zeros only if
2116  	 * they are bounded by ones.
2117  	 */
2118  	clusters = 0;
2119  	zeros = 0;
2120  	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2121  		if (test_bit(i, clustermap)) {
2122  			clusters += 1 + zeros;
2123  			zeros = 0;
2124  		} else
2125  			++zeros;
2126  	}
2127  
2128  	/* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2129  	 * not guaranteed to be synced between boards
2130  	 */
2131  	if (is_vsmp_box() && clusters > 1)
2132  		return 1;
2133  
2134  	/*
2135  	 * If clusters > 2, then should be multi-chassis.
2136  	 * May have to revisit this when multi-core + hyperthreaded CPUs come
2137  	 * out, but AFAIK this will work even for them.
2138  	 */
2139  	return (clusters > 2);
2140  }
2141  #endif
2142  
2143  /*
2144   * APIC command line parameters
2145   */
setup_disableapic(char * arg)2146  static int __init setup_disableapic(char *arg)
2147  {
2148  	disable_apic = 1;
2149  	setup_clear_cpu_cap(X86_FEATURE_APIC);
2150  	return 0;
2151  }
2152  early_param("disableapic", setup_disableapic);
2153  
2154  /* same as disableapic, for compatibility */
setup_nolapic(char * arg)2155  static int __init setup_nolapic(char *arg)
2156  {
2157  	return setup_disableapic(arg);
2158  }
2159  early_param("nolapic", setup_nolapic);
2160  
parse_lapic_timer_c2_ok(char * arg)2161  static int __init parse_lapic_timer_c2_ok(char *arg)
2162  {
2163  	local_apic_timer_c2_ok = 1;
2164  	return 0;
2165  }
2166  early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2167  
parse_disable_apic_timer(char * arg)2168  static int __init parse_disable_apic_timer(char *arg)
2169  {
2170  	disable_apic_timer = 1;
2171  	return 0;
2172  }
2173  early_param("noapictimer", parse_disable_apic_timer);
2174  
parse_nolapic_timer(char * arg)2175  static int __init parse_nolapic_timer(char *arg)
2176  {
2177  	disable_apic_timer = 1;
2178  	return 0;
2179  }
2180  early_param("nolapic_timer", parse_nolapic_timer);
2181  
apic_set_verbosity(char * arg)2182  static int __init apic_set_verbosity(char *arg)
2183  {
2184  	if (!arg)  {
2185  #ifdef CONFIG_X86_64
2186  		skip_ioapic_setup = 0;
2187  		return 0;
2188  #endif
2189  		return -EINVAL;
2190  	}
2191  
2192  	if (strcmp("debug", arg) == 0)
2193  		apic_verbosity = APIC_DEBUG;
2194  	else if (strcmp("verbose", arg) == 0)
2195  		apic_verbosity = APIC_VERBOSE;
2196  	else {
2197  		pr_warning("APIC Verbosity level %s not recognised"
2198  			" use apic=verbose or apic=debug\n", arg);
2199  		return -EINVAL;
2200  	}
2201  
2202  	return 0;
2203  }
2204  early_param("apic", apic_set_verbosity);
2205  
lapic_insert_resource(void)2206  static int __init lapic_insert_resource(void)
2207  {
2208  	if (!apic_phys)
2209  		return -1;
2210  
2211  	/* Put local APIC into the resource map. */
2212  	lapic_resource.start = apic_phys;
2213  	lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2214  	insert_resource(&iomem_resource, &lapic_resource);
2215  
2216  	return 0;
2217  }
2218  
2219  /*
2220   * need call insert after e820_reserve_resources()
2221   * that is using request_resource
2222   */
2223  late_initcall(lapic_insert_resource);
2224