arch/x86/kernel/jailhouse.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Jailhouse paravirt_ops implementation
   4  *
   5  * Copyright (c) Siemens AG, 2015-2017
   6  *
   7  * Authors:
   8  *  Jan Kiszka <jan.kiszka@siemens.com>
   9  */
  10
  11 #include <linux/acpi_pmtmr.h>
  12 #include <linux/kernel.h>
  13 #include <linux/reboot.h>
  14 #include <asm/apic.h>
  15 #include <asm/cpu.h>
  16 #include <asm/hypervisor.h>
  17 #include <asm/i8259.h>
  18 #include <asm/irqdomain.h>
  19 #include <asm/pci_x86.h>
  20 #include <asm/reboot.h>
  21 #include <asm/setup.h>
  22 #include <asm/jailhouse_para.h>
  23
  24 static __initdata struct jailhouse_setup_data setup_data;
  25 static unsigned int precalibrated_tsc_khz;
  26
  27 static uint32_t jailhouse_cpuid_base(void)
  28 {
  29         if (boot_cpu_data.cpuid_level < 0 ||
  30             !boot_cpu_has(X86_FEATURE_HYPERVISOR))
  31                 return 0;
  32
  33         return hypervisor_cpuid_base("Jailhouse\0\0\0", 0);
  34 }
  35
  36 static uint32_t __init jailhouse_detect(void)
  37 {
  38         return jailhouse_cpuid_base();
  39 }
  40
  41 static void jailhouse_get_wallclock(struct timespec64 *now)
  42 {
  43         memset(now, 0, sizeof(*now));
  44 }
  45
  46 static void __init jailhouse_timer_init(void)
  47 {
  48         lapic_timer_frequency = setup_data.apic_khz * (1000 / HZ);
  49 }
  50
  51 static unsigned long jailhouse_get_tsc(void)
  52 {
  53         return precalibrated_tsc_khz;
  54 }
  55
  56 static void __init jailhouse_x2apic_init(void)
  57 {
  58 #ifdef CONFIG_X86_X2APIC
  59         if (!x2apic_enabled())
  60                 return;
  61         /*
  62          * We do not have access to IR inside Jailhouse non-root cells.  So
  63          * we have to run in physical mode.
  64          */
  65         x2apic_phys = 1;
  66         /*
  67          * This will trigger the switch to apic_x2apic_phys.  Empty OEM IDs
  68          * ensure that only this APIC driver picks up the call.
  69          */
  70         default_acpi_madt_oem_check("", "");
  71 #endif
  72 }
  73
  74 static void __init jailhouse_get_smp_config(unsigned int early)
  75 {
  76         struct ioapic_domain_cfg ioapic_cfg = {
  77                 .type = IOAPIC_DOMAIN_STRICT,
  78                 .ops = &mp_ioapic_irqdomain_ops,
  79         };
  80         struct mpc_intsrc mp_irq = {
  81                 .type = MP_INTSRC,
  82                 .irqtype = mp_INT,
  83                 .irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE,
  84         };
  85         unsigned int cpu;
  86
  87         jailhouse_x2apic_init();
  88
  89         register_lapic_address(0xfee00000);
  90
  91         for (cpu = 0; cpu < setup_data.num_cpus; cpu++) {
  92                 generic_processor_info(setup_data.cpu_ids[cpu],
  93                                        boot_cpu_apic_version);
  94         }
  95
  96         smp_found_config = 1;
  97
  98         if (setup_data.standard_ioapic) {
  99                 mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg);
 100
 101                 /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */
 102                 mp_irq.srcbusirq = mp_irq.dstirq = 3;
 103                 mp_save_irq(&mp_irq);
 104
 105                 mp_irq.srcbusirq = mp_irq.dstirq = 4;
 106                 mp_save_irq(&mp_irq);
 107         }
 108 }
 109
 110 static void jailhouse_no_restart(void)
 111 {
 112         pr_notice("Jailhouse: Restart not supported, halting\n");
 113         machine_halt();
 114 }
 115
 116 static int __init jailhouse_pci_arch_init(void)
 117 {
 118         pci_direct_init(1);
 119
 120         /*
 121          * There are no bridges on the virtual PCI root bus under Jailhouse,
 122          * thus no other way to discover all devices than a full scan.
 123          * Respect any overrides via the command line, though.
 124          */
 125         if (pcibios_last_bus < 0)
 126                 pcibios_last_bus = 0xff;
 127
 128 #ifdef CONFIG_PCI_MMCONFIG
 129         if (setup_data.pci_mmconfig_base) {
 130                 pci_mmconfig_add(0, 0, pcibios_last_bus,
 131                                  setup_data.pci_mmconfig_base);
 132                 pci_mmcfg_arch_init();
 133         }
 134 #endif
 135
 136         return 0;
 137 }
 138
 139 static void __init jailhouse_init_platform(void)
 140 {
 141         u64 pa_data = boot_params.hdr.setup_data;
 142         struct setup_data header;
 143         void *mapping;
 144
 145         x86_init.irqs.pre_vector_init   = x86_init_noop;
 146         x86_init.timers.timer_init      = jailhouse_timer_init;
 147         x86_init.mpparse.get_smp_config = jailhouse_get_smp_config;
 148         x86_init.pci.arch_init          = jailhouse_pci_arch_init;
 149
 150         x86_platform.calibrate_cpu      = jailhouse_get_tsc;
 151         x86_platform.calibrate_tsc      = jailhouse_get_tsc;
 152         x86_platform.get_wallclock      = jailhouse_get_wallclock;
 153         x86_platform.legacy.rtc         = 0;
 154         x86_platform.legacy.warm_reset  = 0;
 155         x86_platform.legacy.i8042       = X86_LEGACY_I8042_PLATFORM_ABSENT;
 156
 157         legacy_pic                      = &null_legacy_pic;
 158
 159         machine_ops.emergency_restart   = jailhouse_no_restart;
 160
 161         while (pa_data) {
 162                 mapping = early_memremap(pa_data, sizeof(header));
 163                 memcpy(&header, mapping, sizeof(header));
 164                 early_memunmap(mapping, sizeof(header));
 165
 166                 if (header.type == SETUP_JAILHOUSE &&
 167                     header.len >= sizeof(setup_data)) {
 168                         pa_data += offsetof(struct setup_data, data);
 169
 170                         mapping = early_memremap(pa_data, sizeof(setup_data));
 171                         memcpy(&setup_data, mapping, sizeof(setup_data));
 172                         early_memunmap(mapping, sizeof(setup_data));
 173
 174                         break;
 175                 }
 176
 177                 pa_data = header.next;
 178         }
 179
 180         if (!pa_data)
 181                 panic("Jailhouse: No valid setup data found");
 182
 183         if (setup_data.compatible_version > JAILHOUSE_SETUP_REQUIRED_VERSION)
 184                 panic("Jailhouse: Unsupported setup data structure");
 185
 186         pmtmr_ioport = setup_data.pm_timer_address;
 187         pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport);
 188
 189         precalibrated_tsc_khz = setup_data.tsc_khz;
 190         setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ);
 191
 192         pci_probe = 0;
 193
 194         /*
 195          * Avoid that the kernel complains about missing ACPI tables - there
 196          * are none in a non-root cell.
 197          */
 198         disable_acpi();
 199 }
 200
 201 bool jailhouse_paravirt(void)
 202 {
 203         return jailhouse_cpuid_base() != 0;
 204 }
 205
 206 static bool jailhouse_x2apic_available(void)
 207 {
 208         /*
 209          * The x2APIC is only available if the root cell enabled it. Jailhouse
 210          * does not support switching between xAPIC and x2APIC.
 211          */
 212         return x2apic_enabled();
 213 }
 214
 215 const struct hypervisor_x86 x86_hyper_jailhouse __refconst = {
 216         .name                   = "Jailhouse",
 217         .detect                 = jailhouse_detect,
 218         .init.init_platform     = jailhouse_init_platform,
 219         .init.x2apic_available  = jailhouse_x2apic_available,
 220 };