1/* 2 * Copyright (c) 2005-2007 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 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. 14 * 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 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 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. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 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> 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 */ 53#include <architecture/i386/pio.h> 54#include <i386/machine_cpu.h> 55#include <i386/cpuid.h> 56#include <i386/mp.h> 57#include <i386/machine_routines.h> 58#include <i386/proc_reg.h> 59#include <i386/tsc.h> 60#include <i386/misc_protos.h> 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> 66 67uint64_t busFCvtt2n = 0; 68uint64_t busFCvtn2t = 0; 69uint64_t tscFreq = 0; 70uint64_t tscFCvtt2n = 0; 71uint64_t tscFCvtn2t = 0; 72uint64_t tscGranularity = 0; 73uint64_t bus2tsc = 0; 74uint64_t busFreq = 0; 75uint32_t flex_ratio = 0; 76uint32_t flex_ratio_min = 0; 77uint32_t flex_ratio_max = 0; 78 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) 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 91#define CPU_FAMILY_PENTIUM_M (0x6) 92 93static const char FSB_Frequency_prop[] = "FSBFrequency"; 94/* 95 * This routine extracts the bus frequency in Hz from the device tree. 96 */ 97static uint64_t 98EFI_FSB_frequency(void) 99{ 100 uint64_t frequency = 0; 101 DTEntry entry; 102 void *value; 103 unsigned int size; 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) { 110 kprintf("EFI_FSB_frequency: property %s not found\n", 111 FSB_Frequency_prop); 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 (!(90*Mega < frequency && frequency < 10*Giga)) { 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 */ 132void 133tsc_init(void) 134{ 135 boolean_t N_by_2_bus_ratio = FALSE; 136 137 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 } 161 162 /* 163 * Get the FSB frequency and conversion factors from EFI. 164 */ 165 busFreq = EFI_FSB_frequency(); 166 167 switch (cpuid_cpufamily()) { 168 case CPUFAMILY_INTEL_HASWELL: 169 case CPUFAMILY_INTEL_IVYBRIDGE: 170 case CPUFAMILY_INTEL_SANDYBRIDGE: 171 case CPUFAMILY_INTEL_WESTMERE: 172 case CPUFAMILY_INTEL_NEHALEM: { 173 uint64_t msr_flex_ratio; 174 uint64_t msr_platform_info; 175 176 /* See if FLEX_RATIO is being used */ 177 msr_flex_ratio = rdmsr64(MSR_FLEX_RATIO); 178 msr_platform_info = rdmsr64(MSR_PLATFORM_INFO); 179 flex_ratio_min = (uint32_t)bitfield(msr_platform_info, 47, 40); 180 flex_ratio_max = (uint32_t)bitfield(msr_platform_info, 15, 8); 181 /* No BIOS-programed flex ratio. Use hardware max as default */ 182 tscGranularity = flex_ratio_max; 183 if (msr_flex_ratio & bit(16)) { 184 /* Flex Enabled: Use this MSR if less than max */ 185 flex_ratio = (uint32_t)bitfield(msr_flex_ratio, 15, 8); 186 if (flex_ratio < flex_ratio_max) 187 tscGranularity = flex_ratio; 188 } 189 190 /* If EFI isn't configured correctly, use a constant 191 * value. See 6036811. 192 */ 193 if (busFreq == 0) 194 busFreq = BASE_NHM_CLOCK_SOURCE; 195 196 break; 197 } 198 default: { 199 uint64_t prfsts; 200 201 prfsts = rdmsr64(IA32_PERF_STS); 202 tscGranularity = (uint32_t)bitfield(prfsts, 44, 40); 203 N_by_2_bus_ratio = (prfsts & bit(46)) != 0; 204 } 205 } 206 207 if (busFreq != 0) { 208 busFCvtt2n = ((1 * Giga) << 32) / busFreq; 209 busFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / busFCvtt2n; 210 } else { 211 panic("tsc_init: EFI not supported!\n"); 212 } 213 214 kprintf(" BUS: Frequency = %6d.%06dMHz, " 215 "cvtt2n = %08X.%08X, cvtn2t = %08X.%08X\n", 216 (uint32_t)(busFreq / Mega), 217 (uint32_t)(busFreq % Mega), 218 (uint32_t)(busFCvtt2n >> 32), (uint32_t)busFCvtt2n, 219 (uint32_t)(busFCvtn2t >> 32), (uint32_t)busFCvtn2t); 220 221 /* 222 * Get the TSC increment. The TSC is incremented by this 223 * on every bus tick. Calculate the TSC conversion factors 224 * to and from nano-seconds. 225 * The tsc granularity is also called the "bus ratio". If the N/2 bit 226 * is set this indicates the bus ration is 0.5 more than this - i.e. 227 * that the true bus ratio is (2*tscGranularity + 1)/2. If we cannot 228 * determine the TSC conversion, assume it ticks at the bus frequency. 229 */ 230 if (tscGranularity == 0) 231 tscGranularity = 1; 232 233 if (N_by_2_bus_ratio) 234 tscFCvtt2n = busFCvtt2n * 2 / (1 + 2*tscGranularity); 235 else 236 tscFCvtt2n = busFCvtt2n / tscGranularity; 237 238 tscFreq = ((1 * Giga) << 32) / tscFCvtt2n; 239 tscFCvtn2t = 0xFFFFFFFFFFFFFFFFULL / tscFCvtt2n; 240 241 kprintf(" TSC: Frequency = %6d.%06dMHz, " 242 "cvtt2n = %08X.%08X, cvtn2t = %08X.%08X, gran = %lld%s\n", 243 (uint32_t)(tscFreq / Mega), 244 (uint32_t)(tscFreq % Mega), 245 (uint32_t)(tscFCvtt2n >> 32), (uint32_t)tscFCvtt2n, 246 (uint32_t)(tscFCvtn2t >> 32), (uint32_t)tscFCvtn2t, 247 tscGranularity, N_by_2_bus_ratio ? " (N/2)" : ""); 248 249 /* 250 * Calculate conversion from BUS to TSC 251 */ 252 bus2tsc = tmrCvt(busFCvtt2n, tscFCvtn2t); 253} 254 255void 256tsc_get_info(tscInfo_t *info) 257{ 258 info->busFCvtt2n = busFCvtt2n; 259 info->busFCvtn2t = busFCvtn2t; 260 info->tscFreq = tscFreq; 261 info->tscFCvtt2n = tscFCvtt2n; 262 info->tscFCvtn2t = tscFCvtn2t; 263 info->tscGranularity = tscGranularity; 264 info->bus2tsc = bus2tsc; 265 info->busFreq = busFreq; 266 info->flex_ratio = flex_ratio; 267 info->flex_ratio_min = flex_ratio_min; 268 info->flex_ratio_max = flex_ratio_max; 269} 270