kernel2/lapic.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <lapic.h>
  20 #include <stdint.h>
  21 #include <pic.h>
  22 #include <interrupt.h>
  23 #include <paging.h>
  24 #include <cpu.h>
  25 #include <isr.h>
  26 #include <debug.h>
  27 #include <memkernel.h>
  28
  29 /**
  30  * Initializes LAPIC
  31  *  @return 0=Success; -1=Failure
  32  */
  33 #include <stddef.h>
  34 int lapic_init() {
  35   uint32_t edx = 0;
  36   cpu_t *cpu = cpu_this;
  37
  38   pic_init();
  39
  40   cpu_id(1,NULL,NULL,NULL,&edx);
  41   if (edx&(1<<9) && 0) {
  42     isr_uselapic = 1;
  43     cpu->uselapic = 1;
  44
  45     lapic = memkernel_findvirt(1)+PAGEOFF(LAPIC_PHYS_ADDRESS);
  46     if (paging_map(PAGEDOWN(lapic),PAGEDOWN(LAPIC_PHYS_ADDRESS),0,1)<0) panic("Cannot map LAPIC\n");
  47
  48     lapic->tpr = 0x20;
  49     lapic->lvt_timer   = 0x20030;
  50     lapic->lvt_thermal = 0x20031;
  51     lapic->lvt_pmc     = 0x20032;
  52     lapic->lvt_lint0   = 0x08700;
  53     lapic->lvt_lint1   = 0x08700;
  54     lapic->lvt_error   = 0x20035;
  55     lapic->spurious    = 0x0010F;
  56
  57     pic_pit_setinterval(0,LAPIC_PIT_CALIBRATE_INTERVAL);
  58
  59     return 0;
  60   }
  61   else {
  62     isr_uselapic = 0;
  63     cpu->uselapic = 0;
  64     cpu->interval = 10; // IRQ0 all 10 ms
  65     pic_pit_setinterval(0,cpu->interval);
  66     return -1;
  67   }
  68 }
  69
  70 /**
  71  * Sends EOI
  72  */
  73 void lapic_eoi() {
  74   lapic->eoi = 0;
  75 }
  76
  77 void lapic_timer_calibrate() {
  78   static unsigned int ticks = 0;
  79   static unsigned int start = 0;
  80   static unsigned int end = 0;
  81   kprintf("LAPIC timer calibration: ticks=%u; start=%u; end=%u\n",ticks,start,end);
  82 }