1 #include "libcflat.h" 2 #include "apic.h" 3 #include "msr.h" 4 #include "processor.h" 5 6 static void *g_apic = (void *)0xfee00000; 7 static void *g_ioapic = (void *)0xfec00000; 8 9 struct apic_ops { 10 u32 (*reg_read)(unsigned reg); 11 void (*reg_write)(unsigned reg, u32 val); 12 void (*icr_write)(u32 val, u32 dest); 13 u32 (*id)(void); 14 }; 15 16 static void outb(unsigned char data, unsigned short port) 17 { 18 asm volatile ("out %0, %1" : : "a"(data), "d"(port)); 19 } 20 21 void eoi(void) 22 { 23 apic_write(APIC_EOI, 0); 24 } 25 26 static u32 xapic_read(unsigned reg) 27 { 28 return *(volatile u32 *)(g_apic + reg); 29 } 30 31 static void xapic_write(unsigned reg, u32 val) 32 { 33 *(volatile u32 *)(g_apic + reg) = val; 34 } 35 36 static void xapic_icr_write(u32 val, u32 dest) 37 { 38 while (xapic_read(APIC_ICR) & APIC_ICR_BUSY) 39 ; 40 xapic_write(APIC_ICR2, dest << 24); 41 xapic_write(APIC_ICR, val); 42 } 43 44 static uint32_t xapic_id(void) 45 { 46 return xapic_read(APIC_ID) >> 24; 47 } 48 49 static const struct apic_ops xapic_ops = { 50 .reg_read = xapic_read, 51 .reg_write = xapic_write, 52 .icr_write = xapic_icr_write, 53 .id = xapic_id, 54 }; 55 56 static const struct apic_ops *apic_ops = &xapic_ops; 57 58 static u32 x2apic_read(unsigned reg) 59 { 60 unsigned a, d; 61 62 asm volatile ("rdmsr" : "=a"(a), "=d"(d) : "c"(APIC_BASE_MSR + reg/16)); 63 return a | (u64)d << 32; 64 } 65 66 static void x2apic_write(unsigned reg, u32 val) 67 { 68 asm volatile ("wrmsr" : : "a"(val), "d"(0), "c"(APIC_BASE_MSR + reg/16)); 69 } 70 71 static void x2apic_icr_write(u32 val, u32 dest) 72 { 73 asm volatile ("wrmsr" : : "a"(val), "d"(dest), 74 "c"(APIC_BASE_MSR + APIC_ICR/16)); 75 } 76 77 static uint32_t x2apic_id(void) 78 { 79 return x2apic_read(APIC_ID); 80 } 81 82 static const struct apic_ops x2apic_ops = { 83 .reg_read = x2apic_read, 84 .reg_write = x2apic_write, 85 .icr_write = x2apic_icr_write, 86 .id = x2apic_id, 87 }; 88 89 u32 apic_read(unsigned reg) 90 { 91 return apic_ops->reg_read(reg); 92 } 93 94 void apic_write(unsigned reg, u32 val) 95 { 96 apic_ops->reg_write(reg, val); 97 } 98 99 bool apic_read_bit(unsigned reg, int n) 100 { 101 reg += (n >> 5) << 4; 102 n &= 31; 103 return (apic_read(reg) & (1 << n)) != 0; 104 } 105 106 void apic_icr_write(u32 val, u32 dest) 107 { 108 apic_ops->icr_write(val, dest); 109 } 110 111 uint32_t apic_id(void) 112 { 113 return apic_ops->id(); 114 } 115 116 int enable_x2apic(void) 117 { 118 unsigned a, b, c, d; 119 120 asm ("cpuid" : "=a"(a), "=b"(b), "=c"(c), "=d"(d) : "0"(1)); 121 122 if (c & (1 << 21)) { 123 asm ("rdmsr" : "=a"(a), "=d"(d) : "c"(MSR_IA32_APICBASE)); 124 a |= 1 << 10; 125 asm ("wrmsr" : : "a"(a), "d"(d), "c"(MSR_IA32_APICBASE)); 126 apic_ops = &x2apic_ops; 127 return 1; 128 } else { 129 return 0; 130 } 131 } 132 133 void reset_apic(void) 134 { 135 u64 disabled = rdmsr(MSR_IA32_APICBASE) & ~(APIC_EN | APIC_EXTD); 136 wrmsr(MSR_IA32_APICBASE, disabled); 137 apic_ops = &xapic_ops; 138 wrmsr(MSR_IA32_APICBASE, disabled | APIC_EN); 139 } 140 141 u32 ioapic_read_reg(unsigned reg) 142 { 143 *(volatile u32 *)g_ioapic = reg; 144 return *(volatile u32 *)(g_ioapic + 0x10); 145 } 146 147 void ioapic_write_reg(unsigned reg, u32 value) 148 { 149 *(volatile u32 *)g_ioapic = reg; 150 *(volatile u32 *)(g_ioapic + 0x10) = value; 151 } 152 153 void ioapic_write_redir(unsigned line, ioapic_redir_entry_t e) 154 { 155 ioapic_write_reg(0x10 + line * 2 + 0, ((u32 *)&e)[0]); 156 ioapic_write_reg(0x10 + line * 2 + 1, ((u32 *)&e)[1]); 157 } 158 159 ioapic_redir_entry_t ioapic_read_redir(unsigned line) 160 { 161 ioapic_redir_entry_t e; 162 163 ((u32 *)&e)[0] = ioapic_read_reg(0x10 + line * 2 + 0); 164 ((u32 *)&e)[1] = ioapic_read_reg(0x10 + line * 2 + 1); 165 return e; 166 167 } 168 169 void set_mask(unsigned line, int mask) 170 { 171 ioapic_redir_entry_t e = ioapic_read_redir(line); 172 173 e.mask = mask; 174 ioapic_write_redir(line, e); 175 } 176 177 void enable_apic(void) 178 { 179 printf("enabling apic\n"); 180 xapic_write(0xf0, 0x1ff); /* spurious vector register */ 181 } 182 183 void mask_pic_interrupts(void) 184 { 185 outb(0xff, 0x21); 186 outb(0xff, 0xa1); 187 } 188