1/* 2 * NOOP APIC driver. 3 * 4 * Does almost nothing and should be substituted by a real apic driver via 5 * probe routine. 6 * 7 * Though in case if apic is disabled (for some reason) we try 8 * to not uglify the caller's code and allow to call (some) apic routines 9 * like self-ipi, etc... 10 */ 11 12#include <linux/threads.h> 13#include <linux/cpumask.h> 14#include <linux/module.h> 15#include <linux/string.h> 16#include <linux/kernel.h> 17#include <linux/ctype.h> 18#include <linux/init.h> 19#include <linux/errno.h> 20#include <asm/fixmap.h> 21#include <asm/mpspec.h> 22#include <asm/apicdef.h> 23#include <asm/apic.h> 24#include <asm/setup.h> 25 26#include <linux/smp.h> 27#include <asm/ipi.h> 28 29#include <linux/interrupt.h> 30#include <asm/acpi.h> 31#include <asm/e820.h> 32 33static void noop_init_apic_ldr(void) { } 34static void noop_send_IPI_mask(const struct cpumask *cpumask, int vector) { } 35static void noop_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) { } 36static void noop_send_IPI_allbutself(int vector) { } 37static void noop_send_IPI_all(int vector) { } 38static void noop_send_IPI_self(int vector) { } 39static void noop_apic_wait_icr_idle(void) { } 40static void noop_apic_icr_write(u32 low, u32 id) { } 41 42static int noop_wakeup_secondary_cpu(int apicid, unsigned long start_eip) 43{ 44 return -1; 45} 46 47static u32 noop_safe_apic_wait_icr_idle(void) 48{ 49 return 0; 50} 51 52static u64 noop_apic_icr_read(void) 53{ 54 return 0; 55} 56 57static int noop_cpu_to_logical_apicid(int cpu) 58{ 59 return 0; 60} 61 62static int noop_phys_pkg_id(int cpuid_apic, int index_msb) 63{ 64 return 0; 65} 66 67static unsigned int noop_get_apic_id(unsigned long x) 68{ 69 return 0; 70} 71 72static int noop_probe(void) 73{ 74 /* 75 * NOOP apic should not ever be 76 * enabled via probe routine 77 */ 78 return 0; 79} 80 81static int noop_apic_id_registered(void) 82{ 83 /* 84 * if we would be really "pedantic" 85 * we should pass read_apic_id() here 86 * but since NOOP suppose APIC ID = 0 87 * lets save a few cycles 88 */ 89 return physid_isset(0, phys_cpu_present_map); 90} 91 92static const struct cpumask *noop_target_cpus(void) 93{ 94 /* only BSP here */ 95 return cpumask_of(0); 96} 97 98static unsigned long noop_check_apicid_used(physid_mask_t *map, int apicid) 99{ 100 return physid_isset(apicid, *map); 101} 102 103static unsigned long noop_check_apicid_present(int bit) 104{ 105 return physid_isset(bit, phys_cpu_present_map); 106} 107 108static void noop_vector_allocation_domain(int cpu, struct cpumask *retmask) 109{ 110 if (cpu != 0) 111 pr_warning("APIC: Vector allocated for non-BSP cpu\n"); 112 cpumask_clear(retmask); 113 cpumask_set_cpu(cpu, retmask); 114} 115 116int noop_apicid_to_node(int logical_apicid) 117{ 118 /* we're always on node 0 */ 119 return 0; 120} 121 122static u32 noop_apic_read(u32 reg) 123{ 124 WARN_ON_ONCE((cpu_has_apic && !disable_apic)); 125 return 0; 126} 127 128static void noop_apic_write(u32 reg, u32 v) 129{ 130 WARN_ON_ONCE(cpu_has_apic && !disable_apic); 131} 132 133struct apic apic_noop = { 134 .name = "noop", 135 .probe = noop_probe, 136 .acpi_madt_oem_check = NULL, 137 138 .apic_id_registered = noop_apic_id_registered, 139 140 .irq_delivery_mode = dest_LowestPrio, 141 /* logical delivery broadcast to all CPUs: */ 142 .irq_dest_mode = 1, 143 144 .target_cpus = noop_target_cpus, 145 .disable_esr = 0, 146 .dest_logical = APIC_DEST_LOGICAL, 147 .check_apicid_used = noop_check_apicid_used, 148 .check_apicid_present = noop_check_apicid_present, 149 150 .vector_allocation_domain = noop_vector_allocation_domain, 151 .init_apic_ldr = noop_init_apic_ldr, 152 153 .ioapic_phys_id_map = default_ioapic_phys_id_map, 154 .setup_apic_routing = NULL, 155 .multi_timer_check = NULL, 156 .apicid_to_node = noop_apicid_to_node, 157 158 .cpu_to_logical_apicid = noop_cpu_to_logical_apicid, 159 .cpu_present_to_apicid = default_cpu_present_to_apicid, 160 .apicid_to_cpu_present = physid_set_mask_of_physid, 161 162 .setup_portio_remap = NULL, 163 .check_phys_apicid_present = default_check_phys_apicid_present, 164 .enable_apic_mode = NULL, 165 166 .phys_pkg_id = noop_phys_pkg_id, 167 168 .mps_oem_check = NULL, 169 170 .get_apic_id = noop_get_apic_id, 171 .set_apic_id = NULL, 172 .apic_id_mask = 0x0F << 24, 173 174 .cpu_mask_to_apicid = default_cpu_mask_to_apicid, 175 .cpu_mask_to_apicid_and = default_cpu_mask_to_apicid_and, 176 177 .send_IPI_mask = noop_send_IPI_mask, 178 .send_IPI_mask_allbutself = noop_send_IPI_mask_allbutself, 179 .send_IPI_allbutself = noop_send_IPI_allbutself, 180 .send_IPI_all = noop_send_IPI_all, 181 .send_IPI_self = noop_send_IPI_self, 182 183 .wakeup_secondary_cpu = noop_wakeup_secondary_cpu, 184 185 /* should be safe */ 186 .trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW, 187 .trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH, 188 189 .wait_for_init_deassert = NULL, 190 191 .smp_callin_clear_local_apic = NULL, 192 .inquire_remote_apic = NULL, 193 194 .read = noop_apic_read, 195 .write = noop_apic_write, 196 .icr_read = noop_apic_icr_read, 197 .icr_write = noop_apic_icr_write, 198 .wait_icr_idle = noop_apic_wait_icr_idle, 199 .safe_wait_icr_idle = noop_safe_apic_wait_icr_idle, 200}; 201