1 2 #include <libcflat.h> 3 #include "processor.h" 4 #include "atomic.h" 5 #include "smp.h" 6 #include "apic.h" 7 #include "fwcfg.h" 8 #include "desc.h" 9 10 #define IPI_VECTOR 0x20 11 12 typedef void (*ipi_function_type)(void *data); 13 14 static struct spinlock ipi_lock; 15 static volatile ipi_function_type ipi_function; 16 static void *volatile ipi_data; 17 static volatile int ipi_done; 18 static volatile bool ipi_wait; 19 static int _cpu_count; 20 static atomic_t active_cpus; 21 22 static __attribute__((used)) void ipi(void) 23 { 24 void (*function)(void *data) = ipi_function; 25 void *data = ipi_data; 26 bool wait = ipi_wait; 27 28 if (!wait) { 29 ipi_done = 1; 30 apic_write(APIC_EOI, 0); 31 } 32 function(data); 33 atomic_dec(&active_cpus); 34 if (wait) { 35 ipi_done = 1; 36 apic_write(APIC_EOI, 0); 37 } 38 } 39 40 asm ( 41 "ipi_entry: \n" 42 " call ipi \n" 43 #ifndef __x86_64__ 44 " iret" 45 #else 46 " iretq" 47 #endif 48 ); 49 50 int cpu_count(void) 51 { 52 return _cpu_count; 53 } 54 55 int smp_id(void) 56 { 57 return this_cpu_read_smp_id(); 58 } 59 60 static void setup_smp_id(void *data) 61 { 62 this_cpu_write_smp_id(apic_id()); 63 } 64 65 static void __on_cpu(int cpu, void (*function)(void *data), void *data, int wait) 66 { 67 const u32 ipi_icr = APIC_INT_ASSERT | APIC_DEST_PHYSICAL | APIC_DM_FIXED | IPI_VECTOR; 68 unsigned int target = id_map[cpu]; 69 70 spin_lock(&ipi_lock); 71 if (target == smp_id()) { 72 function(data); 73 } else { 74 atomic_inc(&active_cpus); 75 ipi_done = 0; 76 ipi_function = function; 77 ipi_data = data; 78 ipi_wait = wait; 79 apic_icr_write(ipi_icr, target); 80 while (!ipi_done) 81 ; 82 } 83 spin_unlock(&ipi_lock); 84 } 85 86 void on_cpu(int cpu, void (*function)(void *data), void *data) 87 { 88 __on_cpu(cpu, function, data, 1); 89 } 90 91 void on_cpu_async(int cpu, void (*function)(void *data), void *data) 92 { 93 __on_cpu(cpu, function, data, 0); 94 } 95 96 void on_cpus(void (*function)(void *data), void *data) 97 { 98 int cpu; 99 100 for (cpu = cpu_count() - 1; cpu >= 0; --cpu) 101 on_cpu_async(cpu, function, data); 102 103 while (cpus_active() > 1) 104 pause(); 105 } 106 107 int cpus_active(void) 108 { 109 return atomic_read(&active_cpus); 110 } 111 112 void smp_init(void) 113 { 114 int i; 115 void ipi_entry(void); 116 117 _cpu_count = fwcfg_get_nb_cpus(); 118 119 setup_idt(); 120 init_apic_map(); 121 set_idt_entry(IPI_VECTOR, ipi_entry, 0); 122 123 setup_smp_id(0); 124 for (i = 1; i < cpu_count(); ++i) 125 on_cpu(i, setup_smp_id, 0); 126 127 atomic_inc(&active_cpus); 128 } 129 130 static void do_reset_apic(void *data) 131 { 132 reset_apic(); 133 } 134 135 void smp_reset_apic(void) 136 { 137 int i; 138 139 reset_apic(); 140 for (i = 1; i < cpu_count(); ++i) 141 on_cpu(i, do_reset_apic, 0); 142 143 atomic_inc(&active_cpus); 144 } 145