src/cpu/x86/lapic/lapic.c

   1 #include <cpu/x86/lapic.h>
   2 #include <console/console.h>
   3 #include <cpu/x86/msr.h>
   4 #include <cpu/x86/mtrr.h>
   5
   6 void setup_lapic(void)
   7 {
   8         /* this is so interrupts work. This is very limited scope --
   9          * linux will do better later, we hope ...
  10          */
  11         /* this is the first way we learned to do it. It fails on real SMP
  12          * stuff. So we have to do things differently ...
  13          * see the Intel mp1.4 spec, page A-3
  14          */
  15
  16 #if NEED_LAPIC == 1
  17         /* Only Pentium Pro and later have those MSR stuff */
  18         msr_t msr;
  19
  20         printk(BIOS_INFO, "Setting up local apic...");
  21
  22         /* Enable the local apic */
  23         msr = rdmsr(LAPIC_BASE_MSR);
  24         msr.lo |= LAPIC_BASE_MSR_ENABLE;
  25         msr.lo &= ~LAPIC_BASE_MSR_ADDR_MASK;
  26         msr.lo |= LAPIC_DEFAULT_BASE;
  27         wrmsr(LAPIC_BASE_MSR, msr);
  28
  29         /*
  30          * Set Task Priority to 'accept all'.
  31          */
  32         lapic_write_around(LAPIC_TASKPRI,
  33                 lapic_read_around(LAPIC_TASKPRI) & ~LAPIC_TPRI_MASK);
  34
  35         /* Put the local apic in virtual wire mode */
  36         lapic_write_around(LAPIC_SPIV,
  37                 (lapic_read_around(LAPIC_SPIV) & ~(LAPIC_VECTOR_MASK))
  38                 | LAPIC_SPIV_ENABLE);
  39         lapic_write_around(LAPIC_LVT0,
  40                 (lapic_read_around(LAPIC_LVT0) &
  41                         ~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
  42                                 LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
  43                                 LAPIC_SEND_PENDING |LAPIC_LVT_RESERVED_1 |
  44                                 LAPIC_DELIVERY_MODE_MASK))
  45                 | (LAPIC_LVT_REMOTE_IRR |LAPIC_SEND_PENDING |
  46                         LAPIC_DELIVERY_MODE_EXTINT)
  47                 );
  48         lapic_write_around(LAPIC_LVT1,
  49                 (lapic_read_around(LAPIC_LVT1) &
  50                         ~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
  51                                 LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
  52                                 LAPIC_SEND_PENDING |LAPIC_LVT_RESERVED_1 |
  53                                 LAPIC_DELIVERY_MODE_MASK))
  54                 | (LAPIC_LVT_REMOTE_IRR |LAPIC_SEND_PENDING |
  55                         LAPIC_DELIVERY_MODE_NMI)
  56                 );
  57
  58         printk(BIOS_DEBUG, " apic_id: 0x%02lx ", lapicid());
  59
  60 #else /* !NEED_LLAPIC */
  61         /* Only Pentium Pro and later have those MSR stuff */
  62         msr_t msr;
  63
  64         printk(BIOS_INFO, "Disabling local apic...");
  65
  66         msr = rdmsr(LAPIC_BASE_MSR);
  67         msr.lo &= ~LAPIC_BASE_MSR_ENABLE;
  68         wrmsr(LAPIC_BASE_MSR, msr);
  69 #endif /* !NEED_LAPIC */
  70         printk(BIOS_INFO, "done.\n");
  71         post_code(0x9b);
  72 }