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; 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 if (reg != APIC_ID) 64 return 0; 65 66 ret = HYPERVISOR_platform_op(&op); 67 if (ret) 68 op.u.pcpu_info.apic_id = BAD_APICID; 69 70 return op.u.pcpu_info.apic_id << 24; 71 } 72 73 static void xen_apic_write(u32 reg, u32 val) 74 { 75 if (reg == APIC_LVTPC) { 76 (void)pmu_apic_update(reg); 77 return; 78 } 79 80 /* Warn to see if there's any stray references */ 81 WARN(1,"register: %x, value: %x\n", reg, val); 82 } 83 84 static u64 xen_apic_icr_read(void) 85 { 86 return 0; 87 } 88 89 static void xen_apic_icr_write(u32 low, u32 id) 90 { 91 /* Warn to see if there's any stray references */ 92 WARN_ON(1); 93 } 94 95 static u32 xen_safe_apic_wait_icr_idle(void) 96 { 97 return 0; 98 } 99 100 static int xen_apic_probe_pv(void) 101 { 102 if (xen_pv_domain()) 103 return 1; 104 105 return 0; 106 } 107 108 static int xen_madt_oem_check(char *oem_id, char *oem_table_id) 109 { 110 return xen_pv_domain(); 111 } 112 113 static int xen_id_always_valid(u32 apicid) 114 { 115 return 1; 116 } 117 118 static int xen_id_always_registered(void) 119 { 120 return 1; 121 } 122 123 static int xen_phys_pkg_id(int initial_apic_id, int index_msb) 124 { 125 return initial_apic_id >> index_msb; 126 } 127 128 static void xen_noop(void) 129 { 130 } 131 132 static void xen_silent_inquire(int apicid) 133 { 134 } 135 136 static int xen_cpu_present_to_apicid(int cpu) 137 { 138 if (cpu_present(cpu)) 139 return cpu_data(cpu).apicid; 140 else 141 return BAD_APICID; 142 } 143 144 static struct apic xen_pv_apic = { 145 .name = "Xen PV", 146 .probe = xen_apic_probe_pv, 147 .acpi_madt_oem_check = xen_madt_oem_check, 148 .apic_id_valid = xen_id_always_valid, 149 .apic_id_registered = xen_id_always_registered, 150 151 /* .delivery_mode and .dest_mode_logical not used by XENPV */ 152 153 .disable_esr = 0, 154 155 .check_apicid_used = default_check_apicid_used, /* Used on 32-bit */ 156 .init_apic_ldr = xen_noop, /* setup_local_APIC calls it */ 157 .ioapic_phys_id_map = default_ioapic_phys_id_map, /* Used on 32-bit */ 158 .setup_apic_routing = NULL, 159 .cpu_present_to_apicid = xen_cpu_present_to_apicid, 160 .apicid_to_cpu_present = physid_set_mask_of_physid, /* Used on 32-bit */ 161 .check_phys_apicid_present = default_check_phys_apicid_present, /* smp_sanity_check needs it */ 162 .phys_pkg_id = xen_phys_pkg_id, /* detect_ht */ 163 164 .get_apic_id = xen_get_apic_id, 165 .set_apic_id = xen_set_apic_id, /* Can be NULL on 32-bit. */ 166 167 .calc_dest_apicid = apic_flat_calc_apicid, 168 169 #ifdef CONFIG_SMP 170 .send_IPI_mask = xen_send_IPI_mask, 171 .send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself, 172 .send_IPI_allbutself = xen_send_IPI_allbutself, 173 .send_IPI_all = xen_send_IPI_all, 174 .send_IPI_self = xen_send_IPI_self, 175 #endif 176 /* .wait_for_init_deassert- used by AP bootup - smp_callin which we don't use */ 177 .inquire_remote_apic = xen_silent_inquire, 178 179 .read = xen_apic_read, 180 .write = xen_apic_write, 181 .eoi_write = xen_apic_write, 182 183 .icr_read = xen_apic_icr_read, 184 .icr_write = xen_apic_icr_write, 185 .wait_icr_idle = xen_noop, 186 .safe_wait_icr_idle = xen_safe_apic_wait_icr_idle, 187 }; 188 189 static void __init xen_apic_check(void) 190 { 191 if (apic == &xen_pv_apic) 192 return; 193 194 pr_info("Switched APIC routing from %s to %s.\n", apic->name, 195 xen_pv_apic.name); 196 apic = &xen_pv_apic; 197 } 198 void __init xen_init_apic(void) 199 { 200 x86_apic_ops.io_apic_read = xen_io_apic_read; 201 /* On PV guests the APIC CPUID bit is disabled so none of the 202 * routines end up executing. */ 203 if (!xen_initial_domain()) 204 apic = &xen_pv_apic; 205 206 x86_platform.apic_post_init = xen_apic_check; 207 } 208 apic_driver(xen_pv_apic); 209