Timothy Pearson | a2f79d5 | 2015-02-16 23:24:26 -0600 | [diff] [blame] | 1 | /* |
| 2 | * This file is part of the coreboot project. |
| 3 | * |
| 4 | * Copyright (C) 2015 Timothy Pearson <tpearson@raptorengineeringinc.com>, Raptor Engineering |
| 5 | * Copyright (C) 2013 Google, Inc. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; version 2 of the License. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
Timothy Pearson | a2f79d5 | 2015-02-16 23:24:26 -0600 | [diff] [blame] | 15 | */ |
| 16 | #include <stdint.h> |
| 17 | #include <arch/cpu.h> |
| 18 | #include <cpu/x86/msr.h> |
| 19 | #include <timer.h> |
| 20 | #include <device/pci.h> |
| 21 | #include <device/pci_ids.h> |
| 22 | |
| 23 | #include <northbridge/amd/amdht/AsPsDefs.h> |
Stefan Reinauer | 991f184 | 2015-11-22 23:40:29 +0100 | [diff] [blame] | 24 | #include <cpu/amd/msr.h> |
Timothy Pearson | a2f79d5 | 2015-02-16 23:24:26 -0600 | [diff] [blame] | 25 | |
| 26 | static struct monotonic_counter { |
| 27 | int initialized; |
| 28 | uint32_t core_frequency; |
| 29 | struct mono_time time; |
| 30 | uint64_t last_value; |
| 31 | } mono_counter; |
| 32 | |
| 33 | static inline uint64_t read_counter_msr(void) |
| 34 | { |
| 35 | msr_t counter_msr; |
| 36 | |
| 37 | counter_msr = rdmsr(TSC_MSR); |
| 38 | |
| 39 | return ((uint64_t)counter_msr.hi << 32) | (uint64_t)counter_msr.lo; |
| 40 | } |
| 41 | |
| 42 | static void init_timer(void) |
| 43 | { |
| 44 | uint8_t model; |
| 45 | uint32_t cpuid_fms; |
| 46 | uint8_t cpufid; |
| 47 | uint8_t cpudid; |
| 48 | uint8_t boost_capable = 0; |
| 49 | |
| 50 | /* Get CPU model */ |
| 51 | cpuid_fms = cpuid_eax(0x80000001); |
| 52 | model = ((cpuid_fms & 0xf0000) >> 16) | ((cpuid_fms & 0xf0) >> 4); |
| 53 | |
| 54 | /* Get boost capability */ |
| 55 | if ((model == 0x8) || (model == 0x9)) { /* revision D */ |
| 56 | boost_capable = (pci_read_config32(dev_find_slot(0, PCI_DEVFN(0x18, 4)), 0x15c) & 0x4) >> 2; |
| 57 | } |
| 58 | |
| 59 | /* Set up TSC (BKDG v3.62 section 2.9.4)*/ |
| 60 | msr_t msr = rdmsr(HWCR_MSR); |
| 61 | msr.lo |= 0x1000000; |
| 62 | wrmsr(HWCR_MSR, msr); |
| 63 | |
| 64 | /* Get core Pstate 0 frequency in MHz */ |
| 65 | msr = rdmsr(0xC0010064 + boost_capable); |
| 66 | cpufid = (msr.lo & 0x3f); |
| 67 | cpudid = (msr.lo & 0x1c0) >> 6; |
| 68 | mono_counter.core_frequency = (100 * (cpufid + 0x10)) / (0x01 << cpudid); |
| 69 | |
| 70 | mono_counter.last_value = read_counter_msr(); |
| 71 | mono_counter.initialized = 1; |
| 72 | } |
| 73 | |
| 74 | void timer_monotonic_get(struct mono_time *mt) |
| 75 | { |
| 76 | uint64_t current_tick; |
| 77 | uint32_t usecs_elapsed = 0; |
| 78 | |
| 79 | if (!mono_counter.initialized) |
| 80 | init_timer(); |
| 81 | |
| 82 | current_tick = read_counter_msr(); |
| 83 | if (mono_counter.core_frequency != 0) |
| 84 | usecs_elapsed = (current_tick - mono_counter.last_value) / mono_counter.core_frequency; |
| 85 | |
| 86 | /* Update current time and tick values only if a full tick occurred. */ |
| 87 | if (usecs_elapsed) { |
| 88 | mono_time_add_usecs(&mono_counter.time, usecs_elapsed); |
| 89 | mono_counter.last_value = current_tick; |
| 90 | } |
| 91 | |
| 92 | /* Save result. */ |
| 93 | *mt = mono_counter.time; |
| 94 | } |