K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 1 | /* |
| 2 | * X86 specific Hyper-V initialization code. |
| 3 | * |
| 4 | * Copyright (C) 2016, Microsoft, Inc. |
| 5 | * |
| 6 | * Author : K. Y. Srinivasan <kys@microsoft.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License version 2 as published |
| 10 | * by the Free Software Foundation. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, but |
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 15 | * NON INFRINGEMENT. See the GNU General Public License for more |
| 16 | * details. |
| 17 | * |
| 18 | */ |
| 19 | |
| 20 | #include <linux/types.h> |
| 21 | #include <asm/hypervisor.h> |
| 22 | #include <asm/hyperv.h> |
| 23 | #include <asm/mshyperv.h> |
| 24 | #include <linux/version.h> |
| 25 | #include <linux/vmalloc.h> |
| 26 | #include <linux/mm.h> |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 27 | #include <linux/clockchips.h> |
Stephen Hemminger | 6707181 | 2017-03-04 18:27:11 -0700 | [diff] [blame] | 28 | #include <linux/hyperv.h> |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 29 | |
Vitaly Kuznetsov | bd2a9ad | 2017-03-03 14:21:40 +0100 | [diff] [blame] | 30 | #ifdef CONFIG_HYPERV_TSCPAGE |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 31 | |
| 32 | static struct ms_hyperv_tsc_page *tsc_pg; |
| 33 | |
Vitaly Kuznetsov | bd2a9ad | 2017-03-03 14:21:40 +0100 | [diff] [blame] | 34 | struct ms_hyperv_tsc_page *hv_get_tsc_page(void) |
| 35 | { |
| 36 | return tsc_pg; |
| 37 | } |
| 38 | |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 39 | static u64 read_hv_clock_tsc(struct clocksource *arg) |
| 40 | { |
Vitaly Kuznetsov | 0733379 | 2017-03-03 14:21:41 +0100 | [diff] [blame] | 41 | u64 current_tick = hv_read_tsc_page(tsc_pg); |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 42 | |
Vitaly Kuznetsov | 0733379 | 2017-03-03 14:21:41 +0100 | [diff] [blame] | 43 | if (current_tick == U64_MAX) |
| 44 | rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 45 | |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 46 | return current_tick; |
| 47 | } |
| 48 | |
| 49 | static struct clocksource hyperv_cs_tsc = { |
| 50 | .name = "hyperv_clocksource_tsc_page", |
| 51 | .rating = 400, |
| 52 | .read = read_hv_clock_tsc, |
| 53 | .mask = CLOCKSOURCE_MASK(64), |
| 54 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 55 | }; |
| 56 | #endif |
| 57 | |
| 58 | static u64 read_hv_clock_msr(struct clocksource *arg) |
| 59 | { |
| 60 | u64 current_tick; |
| 61 | /* |
| 62 | * Read the partition counter to get the current tick count. This count |
| 63 | * is set to 0 when the partition is created and is incremented in |
| 64 | * 100 nanosecond units. |
| 65 | */ |
| 66 | rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); |
| 67 | return current_tick; |
| 68 | } |
| 69 | |
| 70 | static struct clocksource hyperv_cs_msr = { |
| 71 | .name = "hyperv_clocksource_msr", |
| 72 | .rating = 400, |
| 73 | .read = read_hv_clock_msr, |
| 74 | .mask = CLOCKSOURCE_MASK(64), |
| 75 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 76 | }; |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 77 | |
K. Y. Srinivasan | 6ab42a6 | 2017-01-18 16:45:03 -0700 | [diff] [blame] | 78 | static void *hypercall_pg; |
Vitaly Kuznetsov | dee863b | 2017-02-04 09:57:13 -0700 | [diff] [blame] | 79 | struct clocksource *hyperv_cs; |
| 80 | EXPORT_SYMBOL_GPL(hyperv_cs); |
| 81 | |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 82 | /* |
| 83 | * This function is to be invoked early in the boot sequence after the |
| 84 | * hypervisor has been detected. |
| 85 | * |
| 86 | * 1. Setup the hypercall page. |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 87 | * 2. Register Hyper-V specific clocksource. |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 88 | */ |
| 89 | void hyperv_init(void) |
| 90 | { |
| 91 | u64 guest_id; |
| 92 | union hv_x64_msr_hypercall_contents hypercall_msr; |
| 93 | |
| 94 | if (x86_hyper != &x86_hyper_ms_hyperv) |
| 95 | return; |
| 96 | |
| 97 | /* |
| 98 | * Setup the hypercall page and enable hypercalls. |
| 99 | * 1. Register the guest ID |
| 100 | * 2. Enable the hypercall and register the hypercall page |
| 101 | */ |
| 102 | guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); |
| 103 | wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id); |
| 104 | |
K. Y. Srinivasan | 372b1e9 | 2017-02-08 18:30:56 -0700 | [diff] [blame] | 105 | hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX); |
K. Y. Srinivasan | 6ab42a6 | 2017-01-18 16:45:03 -0700 | [diff] [blame] | 106 | if (hypercall_pg == NULL) { |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 107 | wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); |
| 108 | return; |
| 109 | } |
| 110 | |
| 111 | rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); |
| 112 | hypercall_msr.enable = 1; |
K. Y. Srinivasan | 6ab42a6 | 2017-01-18 16:45:03 -0700 | [diff] [blame] | 113 | hypercall_msr.guest_physical_address = vmalloc_to_pfn(hypercall_pg); |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 114 | wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 115 | |
| 116 | /* |
| 117 | * Register Hyper-V specific clocksource. |
| 118 | */ |
Vitaly Kuznetsov | bd2a9ad | 2017-03-03 14:21:40 +0100 | [diff] [blame] | 119 | #ifdef CONFIG_HYPERV_TSCPAGE |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 120 | if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) { |
| 121 | union hv_x64_msr_hypercall_contents tsc_msr; |
| 122 | |
| 123 | tsc_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); |
Vitaly Kuznetsov | dee863b | 2017-02-04 09:57:13 -0700 | [diff] [blame] | 124 | if (!tsc_pg) |
| 125 | goto register_msr_cs; |
| 126 | |
| 127 | hyperv_cs = &hyperv_cs_tsc; |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 128 | |
| 129 | rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); |
| 130 | |
| 131 | tsc_msr.enable = 1; |
| 132 | tsc_msr.guest_physical_address = vmalloc_to_pfn(tsc_pg); |
| 133 | |
| 134 | wrmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); |
Vitaly Kuznetsov | 90b2043 | 2017-03-03 14:21:42 +0100 | [diff] [blame] | 135 | |
| 136 | hyperv_cs_tsc.archdata.vclock_mode = VCLOCK_HVCLOCK; |
| 137 | |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 138 | clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100); |
| 139 | return; |
| 140 | } |
Arnd Bergmann | 73667e3 | 2017-02-14 22:17:17 +0100 | [diff] [blame] | 141 | register_msr_cs: |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 142 | #endif |
| 143 | /* |
| 144 | * For 32 bit guests just use the MSR based mechanism for reading |
| 145 | * the partition counter. |
| 146 | */ |
| 147 | |
Vitaly Kuznetsov | dee863b | 2017-02-04 09:57:13 -0700 | [diff] [blame] | 148 | hyperv_cs = &hyperv_cs_msr; |
K. Y. Srinivasan | 63ed4e0 | 2017-01-19 11:51:46 -0700 | [diff] [blame] | 149 | if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE) |
| 150 | clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100); |
K. Y. Srinivasan | 8730046 | 2017-01-18 16:45:02 -0700 | [diff] [blame] | 151 | } |
K. Y. Srinivasan | 6ab42a6 | 2017-01-18 16:45:03 -0700 | [diff] [blame] | 152 | |
| 153 | /* |
Vitaly Kuznetsov | d6f3609 | 2017-01-28 12:37:14 -0700 | [diff] [blame] | 154 | * This routine is called before kexec/kdump, it does the required cleanup. |
| 155 | */ |
| 156 | void hyperv_cleanup(void) |
| 157 | { |
| 158 | union hv_x64_msr_hypercall_contents hypercall_msr; |
| 159 | |
| 160 | /* Reset our OS id */ |
| 161 | wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); |
| 162 | |
| 163 | /* Reset the hypercall page */ |
| 164 | hypercall_msr.as_uint64 = 0; |
| 165 | wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); |
Vitaly Kuznetsov | 5647dbf | 2017-01-28 12:37:15 -0700 | [diff] [blame] | 166 | |
| 167 | /* Reset the TSC page */ |
| 168 | hypercall_msr.as_uint64 = 0; |
| 169 | wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64); |
Vitaly Kuznetsov | d6f3609 | 2017-01-28 12:37:14 -0700 | [diff] [blame] | 170 | } |
| 171 | EXPORT_SYMBOL_GPL(hyperv_cleanup); |
| 172 | |
| 173 | /* |
K. Y. Srinivasan | 6ab42a6 | 2017-01-18 16:45:03 -0700 | [diff] [blame] | 174 | * hv_do_hypercall- Invoke the specified hypercall |
| 175 | */ |
| 176 | u64 hv_do_hypercall(u64 control, void *input, void *output) |
| 177 | { |
| 178 | u64 input_address = (input) ? virt_to_phys(input) : 0; |
| 179 | u64 output_address = (output) ? virt_to_phys(output) : 0; |
| 180 | #ifdef CONFIG_X86_64 |
| 181 | u64 hv_status = 0; |
| 182 | |
| 183 | if (!hypercall_pg) |
| 184 | return (u64)ULLONG_MAX; |
| 185 | |
| 186 | __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8"); |
| 187 | __asm__ __volatile__("call *%3" : "=a" (hv_status) : |
| 188 | "c" (control), "d" (input_address), |
| 189 | "m" (hypercall_pg)); |
| 190 | |
| 191 | return hv_status; |
| 192 | |
| 193 | #else |
| 194 | |
| 195 | u32 control_hi = control >> 32; |
| 196 | u32 control_lo = control & 0xFFFFFFFF; |
| 197 | u32 hv_status_hi = 1; |
| 198 | u32 hv_status_lo = 1; |
| 199 | u32 input_address_hi = input_address >> 32; |
| 200 | u32 input_address_lo = input_address & 0xFFFFFFFF; |
| 201 | u32 output_address_hi = output_address >> 32; |
| 202 | u32 output_address_lo = output_address & 0xFFFFFFFF; |
| 203 | |
| 204 | if (!hypercall_pg) |
| 205 | return (u64)ULLONG_MAX; |
| 206 | |
| 207 | __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi), |
| 208 | "=a"(hv_status_lo) : "d" (control_hi), |
| 209 | "a" (control_lo), "b" (input_address_hi), |
| 210 | "c" (input_address_lo), "D"(output_address_hi), |
| 211 | "S"(output_address_lo), "m" (hypercall_pg)); |
| 212 | |
| 213 | return hv_status_lo | ((u64)hv_status_hi << 32); |
| 214 | #endif /* !x86_64 */ |
| 215 | } |
| 216 | EXPORT_SYMBOL_GPL(hv_do_hypercall); |
K. Y. Srinivasan | d058fa7 | 2017-01-19 11:51:48 -0700 | [diff] [blame] | 217 | |
| 218 | void hyperv_report_panic(struct pt_regs *regs) |
| 219 | { |
| 220 | static bool panic_reported; |
| 221 | |
| 222 | /* |
| 223 | * We prefer to report panic on 'die' chain as we have proper |
| 224 | * registers to report, but if we miss it (e.g. on BUG()) we need |
| 225 | * to report it on 'panic'. |
| 226 | */ |
| 227 | if (panic_reported) |
| 228 | return; |
| 229 | panic_reported = true; |
| 230 | |
| 231 | wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip); |
| 232 | wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax); |
| 233 | wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx); |
| 234 | wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx); |
| 235 | wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx); |
| 236 | |
| 237 | /* |
| 238 | * Let Hyper-V know there is crash data available |
| 239 | */ |
| 240 | wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY); |
| 241 | } |
| 242 | EXPORT_SYMBOL_GPL(hyperv_report_panic); |
K. Y. Srinivasan | 73638cd | 2017-01-19 11:51:49 -0700 | [diff] [blame] | 243 | |
| 244 | bool hv_is_hypercall_page_setup(void) |
| 245 | { |
| 246 | union hv_x64_msr_hypercall_contents hypercall_msr; |
| 247 | |
| 248 | /* Check if the hypercall page is setup */ |
| 249 | hypercall_msr.as_uint64 = 0; |
| 250 | rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); |
| 251 | |
| 252 | if (!hypercall_msr.enable) |
| 253 | return false; |
| 254 | |
| 255 | return true; |
| 256 | } |
| 257 | EXPORT_SYMBOL_GPL(hv_is_hypercall_page_setup); |