1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/init.h> 3 #include <linux/thread_info.h> 4 5 #include <asm/x86_init.h> 6 #include <asm/apic.h> 7 #include <asm/io_apic.h> 8 #include <asm/xen/hypercall.h> 9 10 #include <xen/xen.h> 11 #include <xen/interface/physdev.h> 12 #include "xen-ops.h" 13 #include "pmu.h" 14 #include "smp.h" 15 16 static unsigned int xen_io_apic_read(unsigned apic, unsigned reg) 17 { 18 struct physdev_apic apic_op; 19 int ret; 20 21 apic_op.apic_physbase = mpc_ioapic_addr(apic); 22 apic_op.reg = reg; 23 ret = HYPERVISOR_physdev_op(PHYSDEVOP_apic_read, &apic_op); 24 if (!ret) 25 return apic_op.value; 26 27 /* fallback to return an emulated IO_APIC values */ 28 if (reg == 0x1) 29 return 0x00170020; 30 else if (reg == 0x0) 31 return apic << 24; 32 33 return 0xfd; 34 } 35 36 static u32 xen_set_apic_id(unsigned int x) 37 { 38 WARN_ON(1); 39 return x; 40 } 41 42 static unsigned int xen_get_apic_id(unsigned long x) 43 { 44 return ((x)>>24) & 0xFFu; 45 } 46 47 static u32 xen_apic_read(u32 reg) 48 { 49 struct xen_platform_op op = { 50 .cmd = XENPF_get_cpuinfo, 51 .interface_version = XENPF_INTERFACE_VERSION, 52 .u.pcpu_info.xen_cpuid = 0, 53 }; 54 int ret = 0; 55 56 /* Shouldn't need this as APIC is turned off for PV, and we only 57 * get called on the bootup processor. But just in case. */ 58 if (!xen_initial_domain() || smp_processor_id()) 59 return 0; 60 61 if (reg == APIC_LVR) 62 return 0x14; 63 #ifdef CONFIG_X86_32 64 if (reg == APIC_LDR) 65 return SET_APIC_LOGICAL_ID(1UL << smp_processor_id()); 66 #endif 67 if (reg != APIC_ID) 68 return 0; 69 70 ret = HYPERVISOR_platform_op(&op); 71 if (ret) 72 op.u.pcpu_info.apic_id = BAD_APICID; 73 74 return op.u.pcpu_info.apic_id << 24; 75 } 76 77 static void xen_apic_write(u32 reg, u32 val) 78 { 79 if (reg == APIC_LVTPC) { 80 (void)pmu_apic_update(reg); 81 return; 82 } 83 84 /* Warn to see if there's any stray references */ 85 WARN(1,"register: %x, value: %x\n", reg, val); 86 } 87 88 static u64 xen_apic_icr_read(void) 89 { 90 return 0; 91 } 92 93 static void xen_apic_icr_write(u32 low, u32 id) 94 { 95 /* Warn to see if there's any stray references */ 96 WARN_ON(1); 97 } 98 99 static u32 xen_safe_apic_wait_icr_idle(void) 100 { 101 return 0; 102 } 103 104 static int xen_apic_probe_pv(void) 105 { 106 if (xen_pv_domain()) 107 return 1; 108 109 return 0; 110 } 111 112 static int xen_madt_oem_check(char *oem_id, char *oem_table_id) 113 { 114 return xen_pv_domain(); 115 } 116 117 static int xen_id_always_valid(u32 apicid) 118 { 119 return 1; 120 } 121 122 static int xen_id_always_registered(void) 123 { 124 return 1; 125 } 126 127 static int xen_phys_pkg_id(int initial_apic_id, int index_msb) 128 { 129 return initial_apic_id >> index_msb; 130 } 131 132 #ifdef CONFIG_X86_32 133 static int xen_x86_32_early_logical_apicid(int cpu) 134 { 135 /* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */ 136 return 1 << cpu; 137 } 138 #endif 139 140 static void xen_noop(void) 141 { 142 } 143 144 static void xen_silent_inquire(int apicid) 145 { 146 } 147 148 static int xen_cpu_present_to_apicid(int cpu) 149 { 150 if (cpu_present(cpu)) 151 return cpu_data(cpu).apicid; 152 else 153 return BAD_APICID; 154 } 155 156 static struct apic xen_pv_apic = { 157 .name = "Xen PV", 158 .probe = xen_apic_probe_pv, 159 .acpi_madt_oem_check = xen_madt_oem_check, 160 .apic_id_valid = xen_id_always_valid, 161 .apic_id_registered = xen_id_always_registered, 162 163 /* .irq_delivery_mode - used in native_compose_msi_msg only */ 164 /* .irq_dest_mode - used in native_compose_msi_msg only */ 165 166 .disable_esr = 0, 167 /* .dest_logical - default_send_IPI_ use it but we use our own. */ 168 .check_apicid_used = default_check_apicid_used, /* Used on 32-bit */ 169 170 .init_apic_ldr = xen_noop, /* setup_local_APIC calls it */ 171 172 .ioapic_phys_id_map = default_ioapic_phys_id_map, /* Used on 32-bit */ 173 .setup_apic_routing = NULL, 174 .cpu_present_to_apicid = xen_cpu_present_to_apicid, 175 .apicid_to_cpu_present = physid_set_mask_of_physid, /* Used on 32-bit */ 176 .check_phys_apicid_present = default_check_phys_apicid_present, /* smp_sanity_check needs it */ 177 .phys_pkg_id = xen_phys_pkg_id, /* detect_ht */ 178 179 .get_apic_id = xen_get_apic_id, 180 .set_apic_id = xen_set_apic_id, /* Can be NULL on 32-bit. */ 181 182 .calc_dest_apicid = apic_flat_calc_apicid, 183 184 #ifdef CONFIG_SMP 185 .send_IPI_mask = xen_send_IPI_mask, 186 .send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself, 187 .send_IPI_allbutself = xen_send_IPI_allbutself, 188 .send_IPI_all = xen_send_IPI_all, 189 .send_IPI_self = xen_send_IPI_self, 190 #endif 191 /* .wait_for_init_deassert- used by AP bootup - smp_callin which we don't use */ 192 .inquire_remote_apic = xen_silent_inquire, 193 194 .read = xen_apic_read, 195 .write = xen_apic_write, 196 .eoi_write = xen_apic_write, 197 198 .icr_read = xen_apic_icr_read, 199 .icr_write = xen_apic_icr_write, 200 .wait_icr_idle = xen_noop, 201 .safe_wait_icr_idle = xen_safe_apic_wait_icr_idle, 202 203 #ifdef CONFIG_X86_32 204 /* generic_processor_info and setup_local_APIC. */ 205 .x86_32_early_logical_apicid = xen_x86_32_early_logical_apicid, 206 #endif 207 }; 208 209 static void __init xen_apic_check(void) 210 { 211 if (apic == &xen_pv_apic) 212 return; 213 214 pr_info("Switched APIC routing from %s to %s.\n", apic->name, 215 xen_pv_apic.name); 216 apic = &xen_pv_apic; 217 } 218 void __init xen_init_apic(void) 219 { 220 x86_apic_ops.io_apic_read = xen_io_apic_read; 221 /* On PV guests the APIC CPUID bit is disabled so none of the 222 * routines end up executing. */ 223 if (!xen_initial_domain()) 224 apic = &xen_pv_apic; 225 226 x86_platform.apic_post_init = xen_apic_check; 227 } 228 apic_driver(xen_pv_apic); 229