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