xref: /openbsd/sys/arch/i386/stand/libsa/machdep.c (revision 4fb9ab68)
1 /*	$OpenBSD: machdep.c,v 1.41 2024/06/26 01:40:49 jsg Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 Tom Cosgrove
5  * Copyright (c) 1997-1999 Michael Shalayeff
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
27  * THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include "libsa.h"
31 #include "biosdev.h"
32 #include <machine/apmvar.h>
33 #include <machine/biosvar.h>
34 #include <machine/psl.h>
35 #include <machine/specialreg.h>
36 #include <machine/vmmvar.h>
37 
38 #ifdef EFIBOOT
39 #include "efiboot.h"
40 #endif
41 
42 volatile struct BIOS_regs	BIOS_regs;
43 
44 #if defined(DEBUG)
45 #define CKPT(c)	(*(u_int16_t*)0xb8148 = 0x4700 + (c))
46 #else
47 #define CKPT(c) /* c */
48 #endif
49 
50 const char *vmm_hv_signature = VMM_HV_SIGNATURE;
51 
52 void
53 machdep(void)
54 {
55 	int i, j, vmm = 0, psl_check;
56 	struct i386_boot_probes *pr;
57 	uint32_t dummy, ebx, ecx, edx;
58 	dev_t dev;
59 
60 	/*
61 	 * The list of probe routines is now in conf.c.
62 	 */
63 	for (i = 0; i < nibprobes; i++) {
64 		pr = &probe_list[i];
65 		if (pr != NULL) {
66 			printf("%s:", pr->name);
67 
68 			for (j = 0; j < pr->count; j++) {
69 				(*(pr->probes)[j])();
70 			}
71 
72 			printf("\n");
73 		}
74 	}
75 
76 	/*
77 	 * The following is a simple check to see if cpuid is supported.
78 	 * We try to toggle bit 21 (PSL_ID) in eflags.  If it works, then
79 	 * cpuid is supported.  If not, there's no cpuid, and we don't
80 	 * try it (don't want /boot to get an invalid opcode exception).
81 	 */
82 	__asm volatile(
83 	    "pushfl\n\t"
84 	    "popl	%2\n\t"
85 	    "xorl	%2, %0\n\t"
86 	    "pushl	%0\n\t"
87 	    "popfl\n\t"
88 	    "pushfl\n\t"
89 	    "popl	%0\n\t"
90 	    "xorl	%2, %0\n\t"		/* If %2 == %0, no cpuid */
91 	    : "=r" (psl_check)
92 	    : "0" (PSL_ID), "r" (0)
93 	    : "cc");
94 
95 	if (psl_check != PSL_ID)
96 		return;
97 
98 	CPUID(0x1, dummy, dummy, ecx, dummy);
99 	if (ecx & CPUIDECX_HV) {
100 		CPUID(0x40000000, dummy, ebx, ecx, edx);
101 		if (memcmp(&ebx, &vmm_hv_signature[0], sizeof(uint32_t)) == 0 &&
102 		   memcmp(&ecx, &vmm_hv_signature[4], sizeof(uint32_t)) == 0 &&
103 		   memcmp(&edx, &vmm_hv_signature[8], sizeof(uint32_t)) == 0)
104 			vmm = 1;
105 	}
106 
107 	/* Set console to com0/115200 by default in vmm */
108 	if (vmm) {
109 		dev = ttydev("com0");
110 		cnspeed(dev, 115200);
111 		cnset(dev);
112 	}
113 }
114 
115 int
116 check_skip_conf(void)
117 {
118 	/* Return non-zero (skip boot.conf) if Control "shift" key down */
119 #ifndef EFIBOOT
120 	return (pc_getshifts(0) & 0x04);
121 #else
122 	return (efi_cons_getshifts(0) & 0x04);
123 #endif
124 }
125