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 void xen_apic_eoi(void) 85 { 86 WARN_ON_ONCE(1); 87 } 88 89 static u64 xen_apic_icr_read(void) 90 { 91 return 0; 92 } 93 94 static void xen_apic_icr_write(u32 low, u32 id) 95 { 96 /* Warn to see if there's any stray references */ 97 WARN_ON(1); 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_phys_pkg_id(int initial_apic_id, int index_msb) 114 { 115 return initial_apic_id >> index_msb; 116 } 117 118 static int xen_cpu_present_to_apicid(int cpu) 119 { 120 if (cpu_present(cpu)) 121 return cpu_data(cpu).apicid; 122 else 123 return BAD_APICID; 124 } 125 126 static struct apic xen_pv_apic = { 127 .name = "Xen PV", 128 .probe = xen_apic_probe_pv, 129 .acpi_madt_oem_check = xen_madt_oem_check, 130 131 /* .delivery_mode and .dest_mode_logical not used by XENPV */ 132 133 .disable_esr = 0, 134 135 .check_apicid_used = default_check_apicid_used, /* Used on 32-bit */ 136 .ioapic_phys_id_map = default_ioapic_phys_id_map, /* Used on 32-bit */ 137 .cpu_present_to_apicid = xen_cpu_present_to_apicid, 138 .phys_pkg_id = xen_phys_pkg_id, /* detect_ht */ 139 140 .max_apic_id = UINT_MAX, 141 .get_apic_id = xen_get_apic_id, 142 .set_apic_id = xen_set_apic_id, /* Can be NULL on 32-bit. */ 143 144 .calc_dest_apicid = apic_flat_calc_apicid, 145 146 #ifdef CONFIG_SMP 147 .send_IPI_mask = xen_send_IPI_mask, 148 .send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself, 149 .send_IPI_allbutself = xen_send_IPI_allbutself, 150 .send_IPI_all = xen_send_IPI_all, 151 .send_IPI_self = xen_send_IPI_self, 152 #endif 153 .read = xen_apic_read, 154 .write = xen_apic_write, 155 .eoi = xen_apic_eoi, 156 157 .icr_read = xen_apic_icr_read, 158 .icr_write = xen_apic_icr_write, 159 }; 160 161 static void __init xen_apic_check(void) 162 { 163 if (apic == &xen_pv_apic) 164 return; 165 166 pr_info("Switched APIC routing from %s to %s.\n", apic->name, 167 xen_pv_apic.name); 168 apic = &xen_pv_apic; 169 } 170 void __init xen_init_apic(void) 171 { 172 x86_apic_ops.io_apic_read = xen_io_apic_read; 173 /* On PV guests the APIC CPUID bit is disabled so none of the 174 * routines end up executing. */ 175 if (!xen_initial_domain()) 176 apic = &xen_pv_apic; 177 178 x86_platform.apic_post_init = xen_apic_check; 179 } 180 apic_driver(xen_pv_apic); 181