minix/kernel/arch/i386/arch_reset.c

   1
   2 #include "kernel/kernel.h"
   3
   4 #include <ctype.h>
   5 #include <string.h>
   6 #include <machine/cmos.h>
   7 #include <machine/bios.h>
   8 #include <machine/cpu.h>
   9 #include <minix/cpufeature.h>
  10 #include <sys/reboot.h>
  11 #include <assert.h>
  12 #include <signal.h>
  13
  14 #include <minix/u64.h>
  15
  16 #include "arch_proto.h"
  17 #include "oxpcie.h"
  18 #include "direct_utils.h"
  19
  20 #ifdef USE_ACPI
  21 #include "acpi.h"
  22 #endif
  23
  24 #define     KBCMDP          4       /* kbd controller port (O) */
  25 #define      KBC_PULSE0     0xfe    /* pulse output bit 0 */
  26 #define      IO_KBD          0x060           /* 8042 Keyboard */
  27
  28 int cpu_has_tsc;
  29
  30 void
  31 reset(void)
  32 {
  33         uint8_t b;
  34         /*
  35          * The keyboard controller has 4 random output pins, one of which is
  36          * connected to the RESET pin on the CPU in many PCs.  We tell the
  37          * keyboard controller to pulse this line a couple of times.
  38          */
  39         outb(IO_KBD + KBCMDP, KBC_PULSE0);
  40         busy_delay_ms(100);
  41         outb(IO_KBD + KBCMDP, KBC_PULSE0);
  42         busy_delay_ms(100);
  43
  44         /*
  45          * Attempt to force a reset via the Reset Control register at
  46          * I/O port 0xcf9.  Bit 2 forces a system reset when it
  47          * transitions from 0 to 1.  Bit 1 selects the type of reset
  48          * to attempt: 0 selects a "soft" reset, and 1 selects a
  49          * "hard" reset.  We try a "hard" reset.  The first write sets
  50          * bit 1 to select a "hard" reset and clears bit 2.  The
  51          * second write forces a 0 -> 1 transition in bit 2 to trigger
  52          * a reset.
  53          */
  54         outb(0xcf9, 0x2);
  55         outb(0xcf9, 0x6);
  56         busy_delay_ms(500);  /* wait 0.5 sec to see if that did it */
  57
  58         /*
  59          * Attempt to force a reset via the Fast A20 and Init register
  60          * at I/O port 0x92.  Bit 1 serves as an alternate A20 gate.
  61          * Bit 0 asserts INIT# when set to 1.  We are careful to only
  62          * preserve bit 1 while setting bit 0.  We also must clear bit
  63          * 0 before setting it if it isn't already clear.
  64          */
  65         b = inb(0x92);
  66         if (b != 0xff) {
  67                 if ((b & 0x1) != 0)
  68                         outb(0x92, b & 0xfe);
  69                 outb(0x92, b | 0x1);
  70                 busy_delay_ms(500);  /* wait 0.5 sec to see if that did it */
  71         }
  72
  73         /* Triple fault */
  74         x86_triplefault();
  75
  76         /* Give up on resetting */
  77         while(1) {
  78                 ;
  79         }
  80 }
  81
  82 static __dead void
  83 halt(void)
  84 {
  85         for ( ; ; )
  86                 halt_cpu();
  87 }
  88
  89 static __dead void
  90 poweroff(void)
  91 {
  92         const char *shutdown_str;
  93
  94 #ifdef USE_ACPI
  95         acpi_poweroff();
  96 #endif
  97         /* Bochs/QEMU poweroff */
  98         shutdown_str = "Shutdown";
  99         while (*shutdown_str) outb(0x8900, *(shutdown_str++));
 100
 101         /* VMware magic power off; likely to halt CPU */
 102         poweroff_vmware_clihlt();
 103
 104         /* fallback option: hang */
 105         halt();
 106 }
 107
 108 __dead void arch_shutdown(int how)
 109 {
 110         unsigned char unused_ch;
 111         /* Mask all interrupts, including the clock. */
 112         outb( INT_CTLMASK, ~0);
 113
 114         /* Empty buffer */
 115         while(direct_read_char(&unused_ch))
 116                 ;
 117
 118         if(kinfo.minix_panicing) {
 119                 /* Printing is done synchronously over serial. */
 120                 if (kinfo.do_serial_debug)
 121                         reset();
 122
 123                 /* Print accumulated diagnostics buffer and reset. */
 124                 direct_cls();
 125                 direct_print("Minix panic. System diagnostics buffer:\n\n");
 126                 direct_print(kmess.kmess_buf);
 127                 direct_print("\nSystem has panicked, press any key to reboot");
 128                 while (!direct_read_char(&unused_ch))
 129                         ;
 130                 reset();
 131         }
 132
 133         if((how & RB_POWERDOWN) == RB_POWERDOWN) {
 134                 /* Power off if possible, hang otherwise */
 135                 poweroff();
 136                 NOT_REACHABLE;
 137         }
 138
 139         if(how & RB_HALT) {
 140                 /* Hang */
 141                 for (; ; ) halt_cpu();
 142                 NOT_REACHABLE;
 143         }
 144
 145         /* Reset the system by forcing a processor shutdown.
 146          * First stop the BIOS memory test by setting a soft
 147          * reset flag.
 148          */
 149         reset();
 150         NOT_REACHABLE;
 151 }
 152
 153 #ifdef DEBUG_SERIAL
 154 void ser_putc(char c)
 155 {
 156         int i;
 157         int lsr, thr;
 158
 159 #if CONFIG_OXPCIE
 160         oxpcie_putc(c);
 161 #else
 162         lsr= COM1_LSR;
 163         thr= COM1_THR;
 164         for (i= 0; i<100000; i++)
 165         {
 166                 if (inb( lsr) & LSR_THRE)
 167                         break;
 168         }
 169         outb( thr, c);
 170 #endif
 171 }
 172
 173 #endif