[apple/xnu.git] / osfmk / i386 / tsc.c

/*
 * Copyright (c) 2005-2007 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */

/*
 *	File:		i386/tsc.c
 *	Purpose:	Initializes the TSC and the various conversion
 *			factors needed by other parts of the system.
 */

#include <platforms.h>

#include <mach/mach_types.h>

#include <kern/cpu_data.h>
#include <kern/cpu_number.h>
#include <kern/clock.h>
#include <kern/host_notify.h>
#include <kern/macro_help.h>
#include <kern/misc_protos.h>
#include <kern/spl.h>
#include <kern/assert.h>
#include <mach/vm_prot.h>
#include <vm/pmap.h>
#include <vm/vm_kern.h>		/* for kernel_map */
#include <architecture/i386/pio.h>
#include <i386/machine_cpu.h>
#include <i386/cpuid.h>
#include <i386/mp.h>
#include <i386/machine_routines.h>
#include <i386/proc_reg.h>
#include <i386/tsc.h>
#include <i386/misc_protos.h>
#include <pexpert/pexpert.h>
#include <machine/limits.h>
#include <machine/commpage.h>
#include <sys/kdebug.h>
#include <pexpert/device_tree.h>

uint64_t	busFCvtt2n = 0;
uint64_t	busFCvtn2t = 0;
uint64_t	tscFreq = 0;
uint64_t	tscFCvtt2n = 0;
uint64_t	tscFCvtn2t = 0;
uint64_t	tscGranularity = 0;
uint64_t	bus2tsc = 0;
uint64_t	busFreq = 0;
uint32_t	flex_ratio = 0;
uint32_t	flex_ratio_min = 0;
uint32_t	flex_ratio_max = 0;


#define bit(n)		(1ULL << (n))
#define bitmask(h,l)	((bit(h)|(bit(h)-1)) & ~(bit(l)-1))
#define bitfield(x,h,l)	(((x) & bitmask(h,l)) >> l)

/* Decimal powers: */
#define kilo (1000ULL)
#define Mega (kilo * kilo)
#define Giga (kilo * Mega)
#define Tera (kilo * Giga)
#define Peta (kilo * Tera)

#define CPU_FAMILY_PENTIUM_M	(0x6)

static const char	FSB_Frequency_prop[] = "FSBFrequency";
/*
 * This routine extracts the bus frequency in Hz from the device tree.
 */
static uint64_t
EFI_FSB_frequency(void)
{
	uint64_t	frequency = 0;
	DTEntry		entry;
	void		*value;
	unsigned int	size;

	if (DTLookupEntry(0, "/efi/platform", &entry) != kSuccess) {
		kprintf("EFI_FSB_frequency: didn't find /efi/platform\n");
		return 0;
	}
	if (DTGetProperty(entry,FSB_Frequency_prop,&value,&size) != kSuccess) {
		kprintf("EFI_FSB_frequency: property %s not found\n",
			FSB_Frequency_prop);
		return 0;
	}
	if (size == sizeof(uint64_t)) {
		frequency = *(uint64_t *) value;
		kprintf("EFI_FSB_frequency: read %s value: %llu\n",
			FSB_Frequency_prop, frequency);
		if (!(90*Mega < frequency && frequency < 10*Giga)) {
			kprintf("EFI_FSB_frequency: value out of range\n");
			frequency = 0;
		}
	} else {
		kprintf("EFI_FSB_frequency: unexpected size %d\n", size);
	}
	return frequency;
}

/*
 * Initialize the various conversion factors needed by code referencing
 * the TSC.
 */
void
tsc_init(void)
{
	boolean_t	N_by_2_bus_ratio = FALSE;

	if (cpuid_vmm_present()) {
		kprintf("VMM vendor %u TSC frequency %u KHz bus frequency %u KHz\n",
				cpuid_vmm_info()->cpuid_vmm_family,
				cpuid_vmm_info()->cpuid_vmm_tsc_frequency,
				cpuid_vmm_info()->cpuid_vmm_bus_frequency);

		if (cpuid_vmm_info()->cpuid_vmm_tsc_frequency &&
			cpuid_vmm_info()->cpuid_vmm_bus_frequency) {

			busFreq = (uint64_t)cpuid_vmm_info()->cpuid_vmm_bus_frequency * kilo;
			busFCvtt2n = ((1 * Giga) << 32) / busFreq;
			busFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / busFCvtt2n;
			
			tscFreq = (uint64_t)cpuid_vmm_info()->cpuid_vmm_tsc_frequency * kilo;
			tscFCvtt2n = ((1 * Giga) << 32) / tscFreq;
			tscFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / tscFCvtt2n;
			
			tscGranularity = tscFreq / busFreq;
			
			bus2tsc = tmrCvt(busFCvtt2n, tscFCvtn2t);

			return;
		}
	}

	/*
	 * Get the FSB frequency and conversion factors from EFI.
	 */
	busFreq = EFI_FSB_frequency();

	switch (cpuid_cpufamily()) {
	case CPUFAMILY_INTEL_IVYBRIDGE:
	case CPUFAMILY_INTEL_SANDYBRIDGE:
	case CPUFAMILY_INTEL_WESTMERE:
	case CPUFAMILY_INTEL_NEHALEM: {
		uint64_t msr_flex_ratio;
		uint64_t msr_platform_info;

		/* See if FLEX_RATIO is being used */
		msr_flex_ratio = rdmsr64(MSR_FLEX_RATIO);
		msr_platform_info = rdmsr64(MSR_PLATFORM_INFO);
		flex_ratio_min = (uint32_t)bitfield(msr_platform_info, 47, 40);
		flex_ratio_max = (uint32_t)bitfield(msr_platform_info, 15, 8);
		/* No BIOS-programed flex ratio. Use hardware max as default */
		tscGranularity = flex_ratio_max;
		if (msr_flex_ratio & bit(16)) {
		 	/* Flex Enabled: Use this MSR if less than max */
			flex_ratio = (uint32_t)bitfield(msr_flex_ratio, 15, 8);
			if (flex_ratio < flex_ratio_max)
				tscGranularity = flex_ratio;
		}

		/* If EFI isn't configured correctly, use a constant 
		 * value. See 6036811.
		 */
		if (busFreq == 0)
		    busFreq = BASE_NHM_CLOCK_SOURCE;

		break;
            }
	default: {
		uint64_t	prfsts;

		prfsts = rdmsr64(IA32_PERF_STS);
		tscGranularity = (uint32_t)bitfield(prfsts, 44, 40);
		N_by_2_bus_ratio = (prfsts & bit(46)) != 0;
	    }
	}

	if (busFreq != 0) {
		busFCvtt2n = ((1 * Giga) << 32) / busFreq;
		busFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / busFCvtt2n;
	} else {
		panic("tsc_init: EFI not supported!\n");
	}

	kprintf(" BUS: Frequency = %6d.%06dMHz, "
		"cvtt2n = %08Xx.%08Xx, cvtn2t = %08Xx.%08Xx\n",
		(uint32_t)(busFreq / Mega),
		(uint32_t)(busFreq % Mega), 
		(uint32_t)(busFCvtt2n >> 32), (uint32_t)busFCvtt2n,
		(uint32_t)(busFCvtn2t >> 32), (uint32_t)busFCvtn2t);

	/*
	 * Get the TSC increment.  The TSC is incremented by this
	 * on every bus tick.  Calculate the TSC conversion factors
	 * to and from nano-seconds.
	 * The tsc granularity is also called the "bus ratio". If the N/2 bit
	 * is set this indicates the bus ration is 0.5 more than this - i.e.
	 * that the true bus ratio is (2*tscGranularity + 1)/2. If we cannot
	 * determine the TSC conversion, assume it ticks at the bus frequency.
	 */
	if (tscGranularity == 0)
		tscGranularity = 1;

	if (N_by_2_bus_ratio)
		tscFCvtt2n = busFCvtt2n * 2 / (1 + 2*tscGranularity);
	else
		tscFCvtt2n = busFCvtt2n / tscGranularity;

	tscFreq = ((1 * Giga)  << 32) / tscFCvtt2n;
	tscFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / tscFCvtt2n;

	kprintf(" TSC: Frequency = %6d.%06dMHz, "
		"cvtt2n = %08Xx.%08Xx, cvtn2t = %08Xx.%08Xx, gran = %lld%s\n",
		(uint32_t)(tscFreq / Mega),
		(uint32_t)(tscFreq % Mega), 
		(uint32_t)(tscFCvtt2n >> 32), (uint32_t)tscFCvtt2n,
		(uint32_t)(tscFCvtn2t >> 32), (uint32_t)tscFCvtn2t,
		tscGranularity, N_by_2_bus_ratio ? " (N/2)" : "");

	/*
	 * Calculate conversion from BUS to TSC
	 */
	bus2tsc = tmrCvt(busFCvtt2n, tscFCvtn2t);
}

void
tsc_get_info(tscInfo_t *info)
{
	info->busFCvtt2n     = busFCvtt2n;
	info->busFCvtn2t     = busFCvtn2t;
	info->tscFreq        = tscFreq;
	info->tscFCvtt2n     = tscFCvtt2n;
	info->tscFCvtn2t     = tscFCvtn2t;
	info->tscGranularity = tscGranularity;
	info->bus2tsc        = bus2tsc;
	info->busFreq        = busFreq;
	info->flex_ratio     = flex_ratio;
	info->flex_ratio_min = flex_ratio_min;
	info->flex_ratio_max = flex_ratio_max;
}
Commit	Line	Data
0c530ab8	1	/*
2d21ac55	2	* Copyright (c) 2005-2007 Apple Inc. All rights reserved.
0c530ab8	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
0c530ab8	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
0c530ab8	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
0c530ab8 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
0c530ab8 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
0c530ab8	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
0c530ab8 A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31
	32	/*
	33	* File: i386/tsc.c
	34	* Purpose: Initializes the TSC and the various conversion
	35	* factors needed by other parts of the system.
	36	*/
	37
	38	#include <platforms.h>
0c530ab8 A	39
	40	#include <mach/mach_types.h>
	41
	42	#include <kern/cpu_data.h>
	43	#include <kern/cpu_number.h>
	44	#include <kern/clock.h>
	45	#include <kern/host_notify.h>
	46	#include <kern/macro_help.h>
	47	#include <kern/misc_protos.h>
	48	#include <kern/spl.h>
	49	#include <kern/assert.h>
	50	#include <mach/vm_prot.h>
	51	#include <vm/pmap.h>
	52	#include <vm/vm_kern.h> /* for kernel_map */
0c530ab8	53	#include <architecture/i386/pio.h>
0c530ab8	54	#include <i386/machine_cpu.h>
2d21ac55	55	#include <i386/cpuid.h>
b0d623f7	56	#include <i386/mp.h>
0c530ab8	57	#include <i386/machine_routines.h>
b0d623f7 A	58	#include <i386/proc_reg.h>
	59	#include <i386/tsc.h>
	60	#include <i386/misc_protos.h>
0c530ab8 A	61	#include <pexpert/pexpert.h>
	62	#include <machine/limits.h>
	63	#include <machine/commpage.h>
	64	#include <sys/kdebug.h>
	65	#include <pexpert/device_tree.h>
0c530ab8 A	66
	67	uint64_t busFCvtt2n = 0;
	68	uint64_t busFCvtn2t = 0;
	69	uint64_t tscFreq = 0;
	70	uint64_t tscFCvtt2n = 0;
	71	uint64_t tscFCvtn2t = 0;
	72	uint64_t tscGranularity = 0;
	73	uint64_t bus2tsc = 0;
2d21ac55	74	uint64_t busFreq = 0;
593a1d5f A	75	uint32_t flex_ratio = 0;
	76	uint32_t flex_ratio_min = 0;
	77	uint32_t flex_ratio_max = 0;
	78
2d21ac55 A	79
	80	#define bit(n) (1ULL << (n))
	81	#define bitmask(h,l) ((bit(h)\|(bit(h)-1)) & ~(bit(l)-1))
	82	#define bitfield(x,h,l) (((x) & bitmask(h,l)) >> l)
0c530ab8 A	83
	84	/* Decimal powers: */
	85	#define kilo (1000ULL)
	86	#define Mega (kilo * kilo)
	87	#define Giga (kilo * Mega)
	88	#define Tera (kilo * Giga)
	89	#define Peta (kilo * Tera)
	90
2d21ac55 A	91	#define CPU_FAMILY_PENTIUM_M (0x6)
2d21ac55 A	92
0c530ab8 A	93	static const char FSB_Frequency_prop[] = "FSBFrequency";
0c530ab8 A	94	/*
593a1d5f	95	* This routine extracts the bus frequency in Hz from the device tree.
0c530ab8 A	96	*/
	97	static uint64_t
	98	EFI_FSB_frequency(void)
	99	{
	100	uint64_t frequency = 0;
	101	DTEntry entry;
	102	void *value;
2d21ac55	103	unsigned int size;
0c530ab8 A	104
	105	if (DTLookupEntry(0, "/efi/platform", &entry) != kSuccess) {
	106	kprintf("EFI_FSB_frequency: didn't find /efi/platform\n");
	107	return 0;
	108	}
	109	if (DTGetProperty(entry,FSB_Frequency_prop,&value,&size) != kSuccess) {
2d21ac55 A	110	kprintf("EFI_FSB_frequency: property %s not found\n",
2d21ac55 A	111	FSB_Frequency_prop);
0c530ab8 A	112	return 0;
	113	}
	114	if (size == sizeof(uint64_t)) {
	115	frequency = (uint64_t ) value;
	116	kprintf("EFI_FSB_frequency: read %s value: %llu\n",
	117	FSB_Frequency_prop, frequency);
	118	if (!(90Mega < frequency && frequency < 10Giga)) {
	119	kprintf("EFI_FSB_frequency: value out of range\n");
	120	frequency = 0;
	121	}
	122	} else {
	123	kprintf("EFI_FSB_frequency: unexpected size %d\n", size);
	124	}
	125	return frequency;
	126	}
	127
	128	/*
	129	* Initialize the various conversion factors needed by code referencing
	130	* the TSC.
	131	*/
	132	void
	133	tsc_init(void)
	134	{
2d21ac55 A	135	boolean_t N_by_2_bus_ratio = FALSE;
2d21ac55 A	136
316670eb A	137	if (cpuid_vmm_present()) {
	138	kprintf("VMM vendor %u TSC frequency %u KHz bus frequency %u KHz\n",
	139	cpuid_vmm_info()->cpuid_vmm_family,
	140	cpuid_vmm_info()->cpuid_vmm_tsc_frequency,
	141	cpuid_vmm_info()->cpuid_vmm_bus_frequency);
	142
	143	if (cpuid_vmm_info()->cpuid_vmm_tsc_frequency &&
	144	cpuid_vmm_info()->cpuid_vmm_bus_frequency) {
	145
	146	busFreq = (uint64_t)cpuid_vmm_info()->cpuid_vmm_bus_frequency * kilo;
	147	busFCvtt2n = ((1 * Giga) << 32) / busFreq;
	148	busFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / busFCvtt2n;
	149
	150	tscFreq = (uint64_t)cpuid_vmm_info()->cpuid_vmm_tsc_frequency * kilo;
	151	tscFCvtt2n = ((1 * Giga) << 32) / tscFreq;
	152	tscFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / tscFCvtt2n;
	153
	154	tscGranularity = tscFreq / busFreq;
	155
	156	bus2tsc = tmrCvt(busFCvtt2n, tscFCvtn2t);
	157
	158	return;
	159	}
	160	}
	161
2d21ac55	162	/*
593a1d5f	163	* Get the FSB frequency and conversion factors from EFI.
2d21ac55 A	164	*/
2d21ac55 A	165	busFreq = EFI_FSB_frequency();
593a1d5f	166
7e4a7d39	167	switch (cpuid_cpufamily()) {
13f56ec4	168	case CPUFAMILY_INTEL_IVYBRIDGE:
060df5ea	169	case CPUFAMILY_INTEL_SANDYBRIDGE:
d1ecb069	170	case CPUFAMILY_INTEL_WESTMERE:
7e4a7d39	171	case CPUFAMILY_INTEL_NEHALEM: {
c910b4d9 A	172	uint64_t msr_flex_ratio;
	173	uint64_t msr_platform_info;
	174
	175	/* See if FLEX_RATIO is being used */
	176	msr_flex_ratio = rdmsr64(MSR_FLEX_RATIO);
	177	msr_platform_info = rdmsr64(MSR_PLATFORM_INFO);
	178	flex_ratio_min = (uint32_t)bitfield(msr_platform_info, 47, 40);
	179	flex_ratio_max = (uint32_t)bitfield(msr_platform_info, 15, 8);
	180	/* No BIOS-programed flex ratio. Use hardware max as default */
	181	tscGranularity = flex_ratio_max;
	182	if (msr_flex_ratio & bit(16)) {
	183	/* Flex Enabled: Use this MSR if less than max */
	184	flex_ratio = (uint32_t)bitfield(msr_flex_ratio, 15, 8);
	185	if (flex_ratio < flex_ratio_max)
	186	tscGranularity = flex_ratio;
	187	}
	188
	189	/* If EFI isn't configured correctly, use a constant
	190	* value. See 6036811.
	191	*/
	192	if (busFreq == 0)
b0d623f7	193	busFreq = BASE_NHM_CLOCK_SOURCE;
c910b4d9	194
c910b4d9 A	195	break;
	196	}
	197	default: {
593a1d5f A	198	uint64_t prfsts;
	199
	200	prfsts = rdmsr64(IA32_PERF_STS);
	201	tscGranularity = (uint32_t)bitfield(prfsts, 44, 40);
	202	N_by_2_bus_ratio = (prfsts & bit(46)) != 0;
c910b4d9	203	}
593a1d5f A	204	}
593a1d5f A	205
2d21ac55 A	206	if (busFreq != 0) {
	207	busFCvtt2n = ((1 * Giga) << 32) / busFreq;
	208	busFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / busFCvtt2n;
2d21ac55	209	} else {
593a1d5f	210	panic("tsc_init: EFI not supported!\n");
2d21ac55 A	211	}
2d21ac55 A	212
316670eb A	213	kprintf(" BUS: Frequency = %6d.%06dMHz, "
316670eb A	214	"cvtt2n = %08Xx.%08Xx, cvtn2t = %08Xx.%08Xx\n",
593a1d5f A	215	(uint32_t)(busFreq / Mega),
	216	(uint32_t)(busFreq % Mega),
	217	(uint32_t)(busFCvtt2n >> 32), (uint32_t)busFCvtt2n,
316670eb	218	(uint32_t)(busFCvtn2t >> 32), (uint32_t)busFCvtn2t);
2d21ac55 A	219
	220	/*
	221	* Get the TSC increment. The TSC is incremented by this
	222	* on every bus tick. Calculate the TSC conversion factors
	223	* to and from nano-seconds.
4a3eedf9 A	224	* The tsc granularity is also called the "bus ratio". If the N/2 bit
4a3eedf9 A	225	* is set this indicates the bus ration is 0.5 more than this - i.e.
316670eb A	226	* that the true bus ratio is (2*tscGranularity + 1)/2. If we cannot
316670eb A	227	* determine the TSC conversion, assume it ticks at the bus frequency.
2d21ac55	228	*/
316670eb A	229	if (tscGranularity == 0)
	230	tscGranularity = 1;
	231
2d21ac55	232	if (N_by_2_bus_ratio)
4a3eedf9	233	tscFCvtt2n = busFCvtt2n * 2 / (1 + 2*tscGranularity);
2d21ac55	234	else
4a3eedf9	235	tscFCvtt2n = busFCvtt2n / tscGranularity;
2d21ac55 A	236
	237	tscFreq = ((1 * Giga) << 32) / tscFCvtt2n;
	238	tscFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / tscFCvtt2n;
	239
316670eb A	240	kprintf(" TSC: Frequency = %6d.%06dMHz, "
316670eb A	241	"cvtt2n = %08Xx.%08Xx, cvtn2t = %08Xx.%08Xx, gran = %lld%s\n",
593a1d5f A	242	(uint32_t)(tscFreq / Mega),
	243	(uint32_t)(tscFreq % Mega),
	244	(uint32_t)(tscFCvtt2n >> 32), (uint32_t)tscFCvtt2n,
	245	(uint32_t)(tscFCvtn2t >> 32), (uint32_t)tscFCvtn2t,
	246	tscGranularity, N_by_2_bus_ratio ? " (N/2)" : "");
2d21ac55 A	247
	248	/*
	249	* Calculate conversion from BUS to TSC
	250	*/
	251	bus2tsc = tmrCvt(busFCvtt2n, tscFCvtn2t);
0c530ab8 A	252	}
	253
	254	void
	255	tsc_get_info(tscInfo_t *info)
	256	{
2d21ac55 A	257	info->busFCvtt2n = busFCvtt2n;
	258	info->busFCvtn2t = busFCvtn2t;
	259	info->tscFreq = tscFreq;
	260	info->tscFCvtt2n = tscFCvtt2n;
	261	info->tscFCvtn2t = tscFCvtn2t;
	262	info->tscGranularity = tscGranularity;
	263	info->bus2tsc = bus2tsc;
	264	info->busFreq = busFreq;
593a1d5f A	265	info->flex_ratio = flex_ratio;
	266	info->flex_ratio_min = flex_ratio_min;
	267	info->flex_ratio_max = flex_ratio_max;
0c530ab8	268	}