1 /* 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 29 #include <stand.h> 30 /* 31 #include <sys/param.h> 32 #include <sys/reboot.h> 33 #include <sys/linker.h> 34 #include <machine/bootinfo.h> 35 #include <machine/metadata.h> 36 #include "bootstrap.h" 37 */ 38 #include <machine/psl.h> 39 #include <machine/cpufunc.h> 40 #include <machine/specialreg.h> 41 #include "libi386.h" 42 43 /* 44 * Check to see if this CPU supports long mode. 45 */ 46 int 47 bi_checkcpu(void) 48 { 49 unsigned long flags; 50 unsigned int regs[4]; 51 unsigned int maxeax; 52 unsigned int max_maxeax = 0x100; 53 unsigned int stdfeatures = 0, xtdfeatures = 0; 54 int amd64 = 0; 55 56 /* Check for presence of "cpuid". */ 57 #if defined(__LP64__) 58 flags = read_rflags(); 59 write_rflags(flags ^ PSL_ID); 60 if (!((flags ^ read_rflags()) & PSL_ID)) 61 return (0); 62 #else 63 flags = read_eflags(); 64 write_eflags(flags ^ PSL_ID); 65 if (!((flags ^ read_eflags()) & PSL_ID)) 66 return (0); 67 #endif /* __LP64__ */ 68 69 /* Fetch the vendor string. */ 70 do_cpuid(0, regs); 71 maxeax = regs[0]; 72 73 /* 74 * Limit the range in case of weird hardware 75 */ 76 if (maxeax > max_maxeax) 77 maxeax = max_maxeax; 78 if (maxeax < 1) 79 return (0); 80 else { 81 do_cpuid(1, regs); 82 stdfeatures = regs[3]; 83 } 84 85 /* Has to support AMD features. */ 86 do_cpuid(0x80000000, regs); 87 if (regs[0] & 0x80000000) { 88 maxeax = regs[0]; 89 max_maxeax = 0x80000100; 90 if (maxeax > max_maxeax) 91 maxeax = max_maxeax; 92 if (maxeax >= 0x80000001) { 93 do_cpuid(0x80000001, regs); 94 xtdfeatures = regs[3]; 95 } 96 } 97 98 /* Check for long mode. */ 99 if (xtdfeatures & AMDID_LM) 100 amd64++; 101 102 /* Check for FPU. */ 103 if ((stdfeatures & CPUID_FPU) == 0) 104 amd64 = 0; 105 106 if ((stdfeatures & CPUID_TSC) == 0) 107 amd64 = 0; 108 109 if ((stdfeatures & CPUID_MSR) == 0) 110 amd64 = 0; 111 112 if ((stdfeatures & CPUID_PAE) == 0) 113 amd64 = 0; 114 115 if ((stdfeatures & CPUID_CX8) == 0) 116 amd64 = 0; 117 118 if ((stdfeatures & CPUID_PGE) == 0) 119 amd64 = 0; 120 121 if ((stdfeatures & CPUID_CLFSH) == 0) 122 amd64 = 0; 123 124 if ((stdfeatures & CPUID_MMX) == 0) 125 amd64 = 0; 126 127 if ((stdfeatures & CPUID_FXSR) == 0) 128 amd64 = 0; 129 130 if ((stdfeatures & CPUID_SSE) == 0) 131 amd64 = 0; 132 133 if ((stdfeatures & CPUID_SSE2) == 0) 134 amd64 = 0; 135 136 return (amd64); 137 } 138 139 void 140 bi_isadir(void) 141 { 142 int rc; 143 144 if (bi_checkcpu()) 145 rc = setenv("ISADIR", "amd64", 1); 146 else 147 rc = setenv("ISADIR", "", 1); 148 149 if (rc != 0) { 150 printf("Warning: failed to set ISADIR environment " 151 "variable: %d\n", rc); 152 } 153 } 154