1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2004 James Cleverdon, IBM. 4 * 5 * Flat APIC subarch code. 6 * 7 * Hacked for x86-64 by James Cleverdon from i386 architecture code by 8 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and 9 * James Cleverdon. 10 */ 11 #include <linux/cpumask.h> 12 #include <linux/export.h> 13 #include <linux/acpi.h> 14 15 #include <asm/jailhouse_para.h> 16 #include <asm/apic.h> 17 18 #include "local.h" 19 20 static struct apic apic_physflat; 21 static struct apic apic_flat; 22 23 struct apic *apic __ro_after_init = &apic_flat; 24 EXPORT_SYMBOL_GPL(apic); 25 26 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id) 27 { 28 return 1; 29 } 30 31 static void _flat_send_IPI_mask(unsigned long mask, int vector) 32 { 33 unsigned long flags; 34 35 local_irq_save(flags); 36 __default_send_IPI_dest_field(mask, vector, APIC_DEST_LOGICAL); 37 local_irq_restore(flags); 38 } 39 40 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector) 41 { 42 unsigned long mask = cpumask_bits(cpumask)[0]; 43 44 _flat_send_IPI_mask(mask, vector); 45 } 46 47 static void 48 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) 49 { 50 unsigned long mask = cpumask_bits(cpumask)[0]; 51 int cpu = smp_processor_id(); 52 53 if (cpu < BITS_PER_LONG) 54 __clear_bit(cpu, &mask); 55 56 _flat_send_IPI_mask(mask, vector); 57 } 58 59 static u32 flat_get_apic_id(u32 x) 60 { 61 return (x >> 24) & 0xFF; 62 } 63 64 static int flat_probe(void) 65 { 66 return 1; 67 } 68 69 static struct apic apic_flat __ro_after_init = { 70 .name = "flat", 71 .probe = flat_probe, 72 .acpi_madt_oem_check = flat_acpi_madt_oem_check, 73 74 .dest_mode_logical = true, 75 76 .disable_esr = 0, 77 78 .init_apic_ldr = default_init_apic_ldr, 79 .cpu_present_to_apicid = default_cpu_present_to_apicid, 80 81 .max_apic_id = 0xFE, 82 .get_apic_id = flat_get_apic_id, 83 84 .calc_dest_apicid = apic_flat_calc_apicid, 85 86 .send_IPI = default_send_IPI_single, 87 .send_IPI_mask = flat_send_IPI_mask, 88 .send_IPI_mask_allbutself = flat_send_IPI_mask_allbutself, 89 .send_IPI_allbutself = default_send_IPI_allbutself, 90 .send_IPI_all = default_send_IPI_all, 91 .send_IPI_self = default_send_IPI_self, 92 .nmi_to_offline_cpu = true, 93 94 .read = native_apic_mem_read, 95 .write = native_apic_mem_write, 96 .eoi = native_apic_mem_eoi, 97 .icr_read = native_apic_icr_read, 98 .icr_write = native_apic_icr_write, 99 .wait_icr_idle = apic_mem_wait_icr_idle, 100 .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout, 101 }; 102 103 /* 104 * Physflat mode is used when there are more than 8 CPUs on a system. 105 * We cannot use logical delivery in this case because the mask 106 * overflows, so use physical mode. 107 */ 108 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id) 109 { 110 #ifdef CONFIG_ACPI 111 /* 112 * Quirk: some x86_64 machines can only use physical APIC mode 113 * regardless of how many processors are present (x86_64 ES7000 114 * is an example). 115 */ 116 if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID && 117 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) { 118 printk(KERN_DEBUG "system APIC only can use physical flat"); 119 return 1; 120 } 121 122 if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) { 123 printk(KERN_DEBUG "IBM Summit detected, will use apic physical"); 124 return 1; 125 } 126 #endif 127 128 return 0; 129 } 130 131 static int physflat_probe(void) 132 { 133 return apic == &apic_physflat || num_possible_cpus() > 8 || jailhouse_paravirt(); 134 } 135 136 static struct apic apic_physflat __ro_after_init = { 137 138 .name = "physical flat", 139 .probe = physflat_probe, 140 .acpi_madt_oem_check = physflat_acpi_madt_oem_check, 141 142 .dest_mode_logical = false, 143 144 .disable_esr = 0, 145 146 .cpu_present_to_apicid = default_cpu_present_to_apicid, 147 148 .max_apic_id = 0xFE, 149 .get_apic_id = flat_get_apic_id, 150 151 .calc_dest_apicid = apic_default_calc_apicid, 152 153 .send_IPI = default_send_IPI_single_phys, 154 .send_IPI_mask = default_send_IPI_mask_sequence_phys, 155 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_phys, 156 .send_IPI_allbutself = default_send_IPI_allbutself, 157 .send_IPI_all = default_send_IPI_all, 158 .send_IPI_self = default_send_IPI_self, 159 .nmi_to_offline_cpu = true, 160 161 .read = native_apic_mem_read, 162 .write = native_apic_mem_write, 163 .eoi = native_apic_mem_eoi, 164 .icr_read = native_apic_icr_read, 165 .icr_write = native_apic_icr_write, 166 .wait_icr_idle = apic_mem_wait_icr_idle, 167 .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout, 168 }; 169 170 /* 171 * We need to check for physflat first, so this order is important. 172 */ 173 apic_drivers(apic_physflat, apic_flat); 174