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 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_get_apic_id(u32 x) 35 { 36 return ((x)>>24) & 0xFFu; 37 } 38 39 static u32 xen_apic_read(u32 reg) 40 { 41 struct xen_platform_op op = { 42 .cmd = XENPF_get_cpuinfo, 43 .interface_version = XENPF_INTERFACE_VERSION, 44 }; 45 int ret, cpu; 46 47 if (reg == APIC_LVR) 48 return 0x14; 49 if (reg != APIC_ID) 50 return 0; 51 52 cpu = smp_processor_id(); 53 if (!xen_initial_domain()) 54 return cpu ? cpuid_to_apicid[cpu] << 24 : 0; 55 56 op.u.pcpu_info.xen_cpuid = cpu; 57 58 ret = HYPERVISOR_platform_op(&op); 59 if (ret) 60 op.u.pcpu_info.apic_id = BAD_APICID; 61 62 return op.u.pcpu_info.apic_id << 24; 63 } 64 65 static void xen_apic_write(u32 reg, u32 val) 66 { 67 if (reg == APIC_LVTPC) { 68 (void)pmu_apic_update(reg); 69 return; 70 } 71 72 /* Warn to see if there's any stray references */ 73 WARN(1,"register: %x, value: %x\n", reg, val); 74 } 75 76 static void xen_apic_eoi(void) 77 { 78 WARN_ON_ONCE(1); 79 } 80 81 static u64 xen_apic_icr_read(void) 82 { 83 return 0; 84 } 85 86 static void xen_apic_icr_write(u32 low, u32 id) 87 { 88 /* Warn to see if there's any stray references */ 89 WARN_ON(1); 90 } 91 92 static int xen_apic_probe_pv(void) 93 { 94 if (xen_pv_domain()) 95 return 1; 96 97 return 0; 98 } 99 100 static int xen_madt_oem_check(char *oem_id, char *oem_table_id) 101 { 102 return xen_pv_domain(); 103 } 104 105 static u32 xen_cpu_present_to_apicid(int cpu) 106 { 107 if (cpu_present(cpu)) 108 return cpu_data(cpu).topo.apicid; 109 else 110 return BAD_APICID; 111 } 112 113 static struct apic xen_pv_apic __ro_after_init = { 114 .name = "Xen PV", 115 .probe = xen_apic_probe_pv, 116 .acpi_madt_oem_check = xen_madt_oem_check, 117 118 /* .delivery_mode and .dest_mode_logical not used by XENPV */ 119 120 .disable_esr = 0, 121 122 .cpu_present_to_apicid = xen_cpu_present_to_apicid, 123 124 .max_apic_id = UINT_MAX, 125 .get_apic_id = xen_get_apic_id, 126 127 .calc_dest_apicid = apic_flat_calc_apicid, 128 129 #ifdef CONFIG_SMP 130 .send_IPI_mask = xen_send_IPI_mask, 131 .send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself, 132 .send_IPI_allbutself = xen_send_IPI_allbutself, 133 .send_IPI_all = xen_send_IPI_all, 134 .send_IPI_self = xen_send_IPI_self, 135 #endif 136 .read = xen_apic_read, 137 .write = xen_apic_write, 138 .eoi = xen_apic_eoi, 139 140 .icr_read = xen_apic_icr_read, 141 .icr_write = xen_apic_icr_write, 142 }; 143 apic_driver(xen_pv_apic); 144 145 void __init xen_init_apic(void) 146 { 147 x86_apic_ops.io_apic_read = xen_io_apic_read; 148 } 149