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Rev | Author | Line No. | Line |
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2288 | clevermous | 1 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
2 | ;; ;; |
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9715 | Doczom | 3 | ;; Copyright (C) KolibriOS team 2004-2022. All rights reserved. ;; |
2288 | clevermous | 4 | ;; Distributed under terms of the GNU General Public License ;; |
5 | ;; ;; |
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6 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
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7 | |||
8 | $Revision: 9715 $ |
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9 | |||
4608 | clevermous | 10 | ; Initializes MTRRs. |
11 | proc init_mtrr |
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2288 | clevermous | 12 | |
7132 | dunkaist | 13 | cmp [BOOT.mtrr], byte 2 |
4608 | clevermous | 14 | je .exit |
2288 | clevermous | 15 | |
4608 | clevermous | 16 | bt [cpu_caps], CAPS_MTRR |
17 | jnc .exit |
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2288 | clevermous | 18 | |
4608 | clevermous | 19 | call mtrr_reconfigure |
20 | stdcall set_mtrr, [LFBAddress], 0x1000000, MEM_WC |
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2288 | clevermous | 21 | |
4608 | clevermous | 22 | .exit: |
2288 | clevermous | 23 | ret |
24 | endp |
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25 | |||
4608 | clevermous | 26 | ; Helper procedure for mtrr_reconfigure and set_mtrr, |
27 | ; called before changes in MTRRs. |
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5360 | serge | 28 | ; 1. disable and flush caches |
29 | ; 2. clear PGE bit in cr4 |
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30 | ; 3. flush TLB |
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31 | ; 4. disable mtrr |
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32 | |||
4608 | clevermous | 33 | proc mtrr_begin_change |
34 | mov eax, cr0 |
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35 | or eax, 0x60000000 ;disable caching |
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36 | mov cr0, eax |
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37 | wbinvd ;invalidate cache |
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5360 | serge | 38 | |
39 | bt [cpu_caps], CAPS_PGE |
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40 | jnc .cr3_flush |
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41 | |||
42 | mov eax, cr4 |
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43 | btr eax, 7 ;clear cr4.PGE |
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44 | mov cr4, eax ;flush TLB |
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45 | jmp @F ;skip extra serialization |
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46 | |||
47 | .cr3_flush: |
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48 | mov eax, cr3 |
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49 | mov cr3, eax ;flush TLB |
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50 | @@: |
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51 | mov ecx, MSR_MTRR_DEF_TYPE |
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52 | rdmsr |
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53 | btr eax, 11 ;clear enable flag |
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54 | wrmsr ;disable mtrr |
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2288 | clevermous | 55 | ret |
56 | endp |
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57 | |||
4608 | clevermous | 58 | ; Helper procedure for mtrr_reconfigure and set_mtrr, |
59 | ; called after changes in MTRRs. |
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5360 | serge | 60 | ; 1. enable mtrr |
61 | ; 2. flush all caches |
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62 | ; 3. flush TLB |
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63 | ; 4. restore cr4.PGE flag, if required |
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64 | |||
4608 | clevermous | 65 | proc mtrr_end_change |
5360 | serge | 66 | mov ecx, MSR_MTRR_DEF_TYPE |
67 | rdmsr |
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68 | or ah, 8 ; enable variable-ranges MTRR |
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69 | and al, 0xF0 ; default memtype = UC |
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70 | wrmsr |
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71 | |||
4608 | clevermous | 72 | wbinvd ;again invalidate |
73 | mov eax, cr0 |
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74 | and eax, not 0x60000000 |
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75 | mov cr0, eax ; enable caching |
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5360 | serge | 76 | |
77 | mov eax, cr3 |
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78 | mov cr3, eax ;flush tlb |
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79 | |||
80 | bt [cpu_caps], CAPS_PGE |
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81 | jnc @F |
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82 | |||
83 | mov eax, cr4 |
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84 | bts eax, 7 ;set cr4.PGE flag |
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85 | mov cr4, eax |
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86 | @@: |
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2288 | clevermous | 87 | ret |
88 | endp |
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89 | |||
4608 | clevermous | 90 | ; Some limits to number of structures located in the stack. |
91 | MAX_USEFUL_MTRRS = 16 |
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92 | MAX_RANGES = 16 |
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2288 | clevermous | 93 | |
4608 | clevermous | 94 | ; mtrr_reconfigure keeps a list of MEM_WB ranges. |
95 | ; This structure describes one item in the list. |
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96 | struct mtrr_range |
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97 | next dd ? ; next item |
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98 | start dq ? ; first byte |
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99 | length dq ? ; length in bytes |
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100 | ends |
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2288 | clevermous | 101 | |
4608 | clevermous | 102 | uglobal |
2288 | clevermous | 103 | align 4 |
4608 | clevermous | 104 | num_variable_mtrrs dd 0 ; number of variable-range MTRRs |
105 | endg |
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2288 | clevermous | 106 | |
4608 | clevermous | 107 | ; Helper procedure for MTRR initialization. |
108 | ; Takes MTRR configured by BIOS and tries to recongifure them |
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109 | ; in order to allow non-UC data at top of 4G memory. |
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110 | ; Example: if low part of physical memory is 3.5G = 0xE0000000 bytes wide, |
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111 | ; BIOS can configure two MTRRs so that the first MTRR describes [0, 4G) as WB |
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112 | ; and the second MTRR describes [3.5G, 4G) as UC; |
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113 | ; WB+UC=UC, so the resulting memory map would be as needed, |
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114 | ; but in this configuration our attempts to map LFB at (say) 0xE8000000 as WC |
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115 | ; would be ignored, WB+UC+WC is still UC. |
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116 | ; So we must keep top of 4G memory not covered by MTRRs, |
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117 | ; using three WB MTRRs [0,2G) + [2G,3G) + [3G,3.5G), |
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118 | ; this gives the same memory map, but allows to add further entries. |
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119 | ; See mtrrtest.asm for detailed input/output from real hardware+BIOS. |
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120 | proc mtrr_reconfigure |
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121 | push ebp ; we're called from init_LFB, and it feels hurt when ebp is destroyed |
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122 | ; 1. Prepare local variables. |
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123 | ; 1a. Create list of MAX_RANGES free (aka not yet allocated) ranges. |
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2288 | clevermous | 124 | xor eax, eax |
9715 | Doczom | 125 | lea ecx, [eax + MAX_RANGES] |
4608 | clevermous | 126 | .init_ranges: |
127 | sub esp, sizeof.mtrr_range - 4 |
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128 | push eax |
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129 | mov eax, esp |
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130 | dec ecx |
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131 | jnz .init_ranges |
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132 | mov eax, esp |
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133 | ; 1b. Fill individual local variables. |
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134 | xor edx, edx |
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135 | sub esp, MAX_USEFUL_MTRRS * 16 ; .mtrrs |
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136 | push edx ; .mtrrs_end |
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137 | push edx ; .num_used_mtrrs |
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138 | push eax ; .first_free_range |
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139 | push edx ; .first_range: no ranges yet |
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140 | mov cl, [cpu_phys_addr_width] |
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141 | or eax, -1 |
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142 | shl eax, cl ; note: this uses cl&31 = cl-32, not the entire cl |
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143 | push eax ; .phys_reserved_mask |
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144 | virtual at esp |
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145 | .phys_reserved_mask dd ? |
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146 | .first_range dd ? |
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147 | .first_free_range dd ? |
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148 | .num_used_mtrrs dd ? |
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149 | .mtrrs_end dd ? |
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150 | .mtrrs rq MAX_USEFUL_MTRRS * 2 |
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151 | .local_vars_size = $ - esp |
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152 | end virtual |
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2288 | clevermous | 153 | |
4608 | clevermous | 154 | ; 2. Get the number of variable-range MTRRs from MTRRCAP register. |
155 | ; Abort if zero. |
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156 | mov ecx, 0xFE |
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157 | rdmsr |
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158 | test al, al |
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159 | jz .abort |
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160 | mov byte [num_variable_mtrrs], al |
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161 | ; 3. Validate MTRR_DEF_TYPE register. |
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162 | mov ecx, 0x2FF |
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163 | rdmsr |
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164 | ; If BIOS has not initialized variable-range MTRRs, fallback to step 7. |
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165 | test ah, 8 |
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166 | jz .fill_ranges_from_memory_map |
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167 | ; If the default memory type (not covered by MTRRs) is not UC, |
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168 | ; then probably BIOS did something strange, so it is better to exit immediately |
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169 | ; hoping for the best. |
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170 | cmp al, MEM_UC |
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171 | jnz .abort |
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172 | ; 4. Validate all variable-range MTRRs |
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173 | ; and copy configured MTRRs to the local array [.mtrrs]. |
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174 | ; 4a. Prepare for the loop over existing variable-range MTRRs. |
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175 | mov ecx, 0x200 |
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176 | lea edi, [.mtrrs] |
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177 | .get_used_mtrrs_loop: |
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178 | ; 4b. For every MTRR, read PHYSBASEn and PHYSMASKn. |
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179 | ; In PHYSBASEn, clear upper bits and copy to ebp:ebx. |
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180 | rdmsr |
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181 | or edx, [.phys_reserved_mask] |
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182 | xor edx, [.phys_reserved_mask] |
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183 | mov ebp, edx |
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2288 | clevermous | 184 | mov ebx, eax |
4608 | clevermous | 185 | inc ecx |
186 | ; If PHYSMASKn is not active, ignore this MTRR. |
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187 | rdmsr |
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188 | inc ecx |
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189 | test ah, 8 |
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190 | jz .get_used_mtrrs_next |
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191 | ; 4c. For every active MTRR, check that number of local entries is not too large. |
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192 | inc [.num_used_mtrrs] |
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193 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
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194 | ja .abort |
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195 | ; 4d. For every active MTRR, store PHYSBASEn with upper bits cleared. |
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196 | ; This contains the MTRR base and the memory type in low byte. |
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197 | mov [edi], ebx |
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198 | mov [edi+4], ebp |
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199 | ; 4e. For every active MTRR, check that the range is continuous: |
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200 | ; PHYSMASKn with upper bits set must be negated power of two, and |
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201 | ; low bits of PHYSBASEn must be zeroes: |
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202 | ; PHYSMASKn = 1...10...0, |
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203 | ; PHYSBASEn = x...x0...0, |
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204 | ; this defines a continuous range from x...x0...0 to x...x1...1, |
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205 | ; length = 10...0 = negated PHYSMASKn. |
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206 | ; Store length in the local array. |
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207 | and eax, not 0xFFF |
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208 | or edx, [.phys_reserved_mask] |
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209 | mov dword [edi+8], 0 |
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210 | mov dword [edi+12], 0 |
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211 | sub [edi+8], eax |
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212 | sbb [edi+12], edx |
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213 | ; (x and -x) is the maximum power of two that divides x. |
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214 | ; Condition for powers of two: (x and -x) equals x. |
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215 | and eax, [edi+8] |
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216 | and edx, [edi+12] |
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217 | cmp eax, [edi+8] |
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218 | jnz .abort |
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219 | cmp edx, [edi+12] |
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220 | jnz .abort |
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221 | sub eax, 1 |
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222 | sbb edx, 0 |
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223 | and eax, not 0xFFF |
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224 | and eax, ebx |
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225 | jnz .abort |
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226 | and edx, ebp |
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227 | jnz .abort |
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228 | ; 4f. For every active MTRR, validate memory type: it must be either WB or UC. |
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229 | add edi, 16 |
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230 | cmp bl, MEM_UC |
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231 | jz .get_used_mtrrs_next |
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232 | cmp bl, MEM_WB |
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233 | jnz .abort |
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234 | .get_used_mtrrs_next: |
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235 | ; 4g. Repeat the loop at 4b-4f for all [num_variable_mtrrs] entries. |
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236 | mov eax, [num_variable_mtrrs] |
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237 | lea eax, [0x200+eax*2] |
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238 | cmp ecx, eax |
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239 | jb .get_used_mtrrs_loop |
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240 | ; 4h. If no active MTRRs were detected, fallback to step 7. |
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241 | cmp [.num_used_mtrrs], 0 |
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242 | jz .fill_ranges_from_memory_map |
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243 | mov [.mtrrs_end], edi |
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244 | ; 5. Generate sorted list of ranges marked as WB. |
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245 | ; 5a. Prepare for the loop over configured MTRRs filled at step 4. |
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246 | lea ecx, [.mtrrs] |
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247 | .fill_wb_ranges: |
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248 | ; 5b. Ignore non-WB MTRRs. |
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249 | mov ebx, [ecx] |
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250 | cmp bl, MEM_WB |
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251 | jnz .next_wb_range |
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252 | mov ebp, [ecx+4] |
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253 | and ebx, not 0xFFF ; clear memory type and reserved bits |
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254 | ; ebp:ebx = start of the range described by the current MTRR. |
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255 | ; 5c. Find the first existing range containing a point greater than ebp:ebx. |
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256 | lea esi, [.first_range] |
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257 | .find_range_wb: |
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258 | ; If there is no next range or start of the next range is greater than ebp:ebx, |
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259 | ; exit the loop to 5d. |
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260 | mov edi, [esi] |
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261 | test edi, edi |
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262 | jz .found_place_wb |
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263 | mov eax, ebx |
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264 | mov edx, ebp |
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9715 | Doczom | 265 | sub eax, dword [edi + mtrr_range.start] |
266 | sbb edx, dword [edi + mtrr_range.start+4] |
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4608 | clevermous | 267 | jb .found_place_wb |
268 | ; Otherwise, if end of the next range is greater than or equal to ebp:ebx, |
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269 | ; exit the loop to 5e. |
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270 | mov esi, edi |
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9715 | Doczom | 271 | sub eax, dword [edi + mtrr_range.length] |
272 | sbb edx, dword [edi + mtrr_range.length+4] |
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4608 | clevermous | 273 | jb .expand_wb |
274 | or eax, edx |
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275 | jnz .find_range_wb |
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276 | jmp .expand_wb |
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277 | .found_place_wb: |
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278 | ; 5d. ebp:ebx is not within any existing range. |
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279 | ; Insert a new range between esi and edi. |
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280 | ; (Later, during 5e, it can be merged with the following ranges.) |
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281 | mov eax, [.first_free_range] |
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282 | test eax, eax |
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283 | jz .abort |
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284 | mov [esi], eax |
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9715 | Doczom | 285 | mov edx, [eax + mtrr_range.next] |
4608 | clevermous | 286 | mov [.first_free_range], edx |
9715 | Doczom | 287 | mov dword [eax + mtrr_range.start], ebx |
288 | mov dword [eax + mtrr_range.start+4], ebp |
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4608 | clevermous | 289 | ; Don't fill [eax+mtrr_range.next] and [eax+mtrr_range.length] yet, |
290 | ; they will be calculated including merges at step 5e. |
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291 | mov esi, edi |
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2288 | clevermous | 292 | mov edi, eax |
4608 | clevermous | 293 | .expand_wb: |
294 | ; 5e. The range at edi contains ebp:ebx, and esi points to the first range |
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295 | ; to be checked for merge: esi=edi if ebp:ebx was found in an existing range, |
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296 | ; esi is next after edi if a new range with ebp:ebx was created. |
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297 | ; Merge it with following ranges while start of the next range is not greater |
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298 | ; than the end of the new range. |
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299 | add ebx, [ecx+8] |
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300 | adc ebp, [ecx+12] |
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301 | ; ebp:ebx = end of the range described by the current MTRR. |
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302 | .expand_wb_loop: |
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303 | ; If there is no next range or start of the next range is greater than ebp:ebx, |
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304 | ; exit the loop to 5g. |
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305 | test esi, esi |
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306 | jz .expand_wb_done |
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307 | mov eax, ebx |
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308 | mov edx, ebp |
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9715 | Doczom | 309 | sub eax, dword [esi + mtrr_range.start] |
310 | sbb edx, dword [esi + mtrr_range.start+4] |
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4608 | clevermous | 311 | jb .expand_wb_done |
312 | ; Otherwise, if end of the next range is greater than or equal to ebp:ebx, |
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313 | ; exit the loop to 5f. |
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9715 | Doczom | 314 | sub eax, dword [esi + mtrr_range.length] |
315 | sbb edx, dword [esi + mtrr_range.length+4] |
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4608 | clevermous | 316 | jb .expand_wb_last |
317 | ; Otherwise, the current range is completely within the new range. |
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318 | ; Free it and continue the loop. |
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9715 | Doczom | 319 | mov edx, [esi + mtrr_range.next] |
4608 | clevermous | 320 | cmp esi, edi |
321 | jz @f |
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322 | mov eax, [.first_free_range] |
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9715 | Doczom | 323 | mov [esi + mtrr_range.next], eax |
4608 | clevermous | 324 | mov [.first_free_range], esi |
2288 | clevermous | 325 | @@: |
4608 | clevermous | 326 | mov esi, edx |
327 | jmp .expand_wb_loop |
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328 | .expand_wb_last: |
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329 | ; 5f. Start of the new range is inside range described by esi, |
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330 | ; end of the new range is inside range described by edi. |
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331 | ; If esi is equal to edi, the new range is completely within |
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332 | ; an existing range, so proceed to the next range. |
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333 | cmp esi, edi |
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334 | jz .next_wb_range |
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335 | ; Otherwise, set end of interval at esi to end of interval at edi |
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336 | ; and free range described by edi. |
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9715 | Doczom | 337 | mov ebx, dword [esi + mtrr_range.start] |
338 | mov ebp, dword [esi + mtrr_range.start+4] |
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339 | add ebx, dword [esi + mtrr_range.length] |
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340 | adc ebp, dword [esi + mtrr_range.length+4] |
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341 | mov edx, [esi + mtrr_range.next] |
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4608 | clevermous | 342 | mov eax, [.first_free_range] |
9715 | Doczom | 343 | mov [esi + mtrr_range.next], eax |
4608 | clevermous | 344 | mov [.first_free_range], esi |
345 | mov esi, edx |
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346 | .expand_wb_done: |
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347 | ; 5g. We have found the next range (maybe 0) after merging and |
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348 | ; the new end of range (maybe ebp:ebx from the new range |
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349 | ; or end of another existing interval calculated at step 5f). |
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350 | ; Write them to range at edi. |
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9715 | Doczom | 351 | mov [edi + mtrr_range.next], esi |
352 | sub ebx, dword [edi + mtrr_range.start] |
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353 | sbb ebp, dword [edi + mtrr_range.start+4] |
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354 | mov dword [edi + mtrr_range.length], ebx |
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355 | mov dword [edi + mtrr_range.length+4], ebp |
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4608 | clevermous | 356 | .next_wb_range: |
357 | ; 5h. Continue the loop 5b-5g over all configured MTRRs. |
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358 | add ecx, 16 |
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359 | cmp ecx, [.mtrrs_end] |
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360 | jb .fill_wb_ranges |
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361 | ; 6. Exclude all ranges marked as UC. |
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362 | ; 6a. Prepare for the loop over configured MTRRs filled at step 4. |
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363 | lea ecx, [.mtrrs] |
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364 | .fill_uc_ranges: |
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365 | ; 6b. Ignore non-UC MTRRs. |
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366 | mov ebx, [ecx] |
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367 | cmp bl, MEM_UC |
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368 | jnz .next_uc_range |
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369 | mov ebp, [ecx+4] |
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370 | and ebx, not 0xFFF ; clear memory type and reserved bits |
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371 | ; ebp:ebx = start of the range described by the current MTRR. |
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372 | lea esi, [.first_range] |
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373 | ; 6c. Find the first existing range containing a point greater than ebp:ebx. |
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374 | .find_range_uc: |
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375 | ; If there is no next range, ignore this MTRR, |
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376 | ; exit the loop and continue to next MTRR. |
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377 | mov edi, [esi] |
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378 | test edi, edi |
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379 | jz .next_uc_range |
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380 | ; If start of the next range is greater than or equal to ebp:ebx, |
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381 | ; exit the loop to 6e. |
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9715 | Doczom | 382 | mov eax, dword [edi + mtrr_range.start] |
383 | mov edx, dword [edi + mtrr_range.start+4] |
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4608 | clevermous | 384 | sub eax, ebx |
385 | sbb edx, ebp |
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386 | jnb .truncate_uc |
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387 | ; Otherwise, continue the loop if end of the next range is less than ebp:ebx, |
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388 | ; exit the loop to 6d otherwise. |
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389 | mov esi, edi |
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9715 | Doczom | 390 | add eax, dword [edi + mtrr_range.length] |
391 | adc edx, dword [edi + mtrr_range.length+4] |
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4608 | clevermous | 392 | jnb .find_range_uc |
393 | ; 6d. ebp:ebx is inside (or at end of) an existing range. |
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394 | ; Split the range. (The second range, maybe containing completely within UC-range, |
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395 | ; maybe of zero length, can be removed at step 6e, if needed.) |
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396 | mov edi, [.first_free_range] |
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397 | test edi, edi |
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398 | jz .abort |
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9715 | Doczom | 399 | mov dword [edi + mtrr_range.start], ebx |
400 | mov dword [edi + mtrr_range.start+4], ebp |
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401 | mov dword [edi + mtrr_range.length], eax |
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402 | mov dword [edi + mtrr_range.length+4], edx |
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403 | mov eax, [edi + mtrr_range.next] |
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4608 | clevermous | 404 | mov [.first_free_range], eax |
9715 | Doczom | 405 | mov eax, [esi + mtrr_range.next] |
406 | mov [edi + mtrr_range.next], eax |
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4608 | clevermous | 407 | ; don't change [esi+mtrr_range.next] yet, it will be filled at step 6e |
408 | mov eax, ebx |
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409 | mov edx, ebp |
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9715 | Doczom | 410 | sub eax, dword [esi + mtrr_range.start] |
411 | sbb edx, dword [esi + mtrr_range.start+4] |
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412 | mov dword [esi + mtrr_range.length], eax |
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413 | mov dword [esi + mtrr_range.length+4], edx |
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4608 | clevermous | 414 | .truncate_uc: |
415 | ; 6e. edi is the first range after ebp:ebx, check it and next ranges |
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416 | ; for intersection with the new range, truncate heads. |
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417 | add ebx, [ecx+8] |
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418 | adc ebp, [ecx+12] |
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419 | ; ebp:ebx = end of the range described by the current MTRR. |
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420 | .truncate_uc_loop: |
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421 | ; If start of the next range is greater than ebp:ebx, |
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422 | ; exit the loop to 6g. |
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423 | mov eax, ebx |
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424 | mov edx, ebp |
||
9715 | Doczom | 425 | sub eax, dword [edi + mtrr_range.start] |
426 | sbb edx, dword [edi + mtrr_range.start+4] |
||
4608 | clevermous | 427 | jb .truncate_uc_done |
428 | ; Otherwise, if end of the next range is greater than ebp:ebx, |
||
429 | ; exit the loop to 6f. |
||
9715 | Doczom | 430 | sub eax, dword [edi + mtrr_range.length] |
431 | sbb edx, dword [edi + mtrr_range.length+4] |
||
4608 | clevermous | 432 | jb .truncate_uc_last |
433 | ; Otherwise, the current range is completely within the new range. |
||
434 | ; Free it and continue the loop if there is a next range. |
||
435 | ; If that was a last range, exit the loop to 6g. |
||
9715 | Doczom | 436 | mov edx, [edi + mtrr_range.next] |
4608 | clevermous | 437 | mov eax, [.first_free_range] |
438 | mov [.first_free_range], edi |
||
9715 | Doczom | 439 | mov [edi + mtrr_range.next], eax |
4608 | clevermous | 440 | mov edi, edx |
441 | test edi, edi |
||
442 | jnz .truncate_uc_loop |
||
443 | jmp .truncate_uc_done |
||
444 | .truncate_uc_last: |
||
445 | ; 6f. The range at edi partially intersects with the UC-range described by MTRR. |
||
446 | ; Truncate it from the head. |
||
9715 | Doczom | 447 | mov dword [edi + mtrr_range.start], ebx |
448 | mov dword [edi + mtrr_range.start+4], ebp |
||
4608 | clevermous | 449 | neg eax |
450 | adc edx, 0 |
||
451 | neg edx |
||
9715 | Doczom | 452 | mov dword [edi + mtrr_range.length], eax |
453 | mov dword [edi + mtrr_range.length+4], edx |
||
4608 | clevermous | 454 | .truncate_uc_done: |
455 | ; 6g. We have found the next range (maybe 0) after intersection. |
||
456 | ; Write it to [esi+mtrr_range.next]. |
||
9715 | Doczom | 457 | mov [esi + mtrr_range.next], edi |
4608 | clevermous | 458 | .next_uc_range: |
459 | ; 6h. Continue the loop 6b-6g over all configured MTRRs. |
||
460 | add ecx, 16 |
||
461 | cmp ecx, [.mtrrs_end] |
||
462 | jb .fill_uc_ranges |
||
463 | ; Sanity check: if there are no ranges after steps 5-6, |
||
464 | ; fallback to step 7. Otherwise, go to 8. |
||
465 | cmp [.first_range], 0 |
||
466 | jnz .ranges_ok |
||
467 | .fill_ranges_from_memory_map: |
||
468 | ; 7. BIOS has not configured variable-range MTRRs. |
||
469 | ; Create one range from 0 to [MEM_AMOUNT]. |
||
470 | mov eax, [.first_free_range] |
||
9715 | Doczom | 471 | mov edx, [eax + mtrr_range.next] |
4608 | clevermous | 472 | mov [.first_free_range], edx |
473 | mov [.first_range], eax |
||
474 | xor edx, edx |
||
9715 | Doczom | 475 | mov [eax + mtrr_range.next], edx |
476 | mov dword [eax + mtrr_range.start], edx |
||
477 | mov dword [eax + mtrr_range.start+4], edx |
||
4608 | clevermous | 478 | mov ecx, [MEM_AMOUNT] |
9715 | Doczom | 479 | mov dword [eax + mtrr_range.length], ecx |
480 | mov dword [eax + mtrr_range.length+4], edx |
||
4608 | clevermous | 481 | .ranges_ok: |
482 | ; 8. We have calculated list of WB-ranges. |
||
483 | ; Now we should calculate a list of MTRRs so that |
||
484 | ; * every MTRR describes a range with length = power of 2 and start that is aligned, |
||
485 | ; * every MTRR can be WB or UC |
||
486 | ; * (sum of all WB ranges) minus (sum of all UC ranges) equals the calculated list |
||
487 | ; * top of 4G memory must not be covered by any ranges |
||
488 | ; Example: range [0,0xBC000000) can be converted to |
||
489 | ; [0,0x80000000)+[0x80000000,0xC0000000)-[0xBC000000,0xC0000000) |
||
490 | ; WB +WB -UC |
||
491 | ; but not to [0,0x100000000)-[0xC0000000,0x100000000)-[0xBC000000,0xC0000000). |
||
492 | ; 8a. Check that list of ranges is [0,something) plus, optionally, [4G,something). |
||
493 | ; This holds in practice (see mtrrtest.asm for real-life examples) |
||
494 | ; and significantly simplifies the code: ranges are independent, start of range |
||
495 | ; is almost always aligned (the only exception >4G upper memory can be easily covered), |
||
496 | ; there is no need to consider adding holes before start of range, only |
||
497 | ; append them to end of range. |
||
2288 | clevermous | 498 | xor eax, eax |
4608 | clevermous | 499 | mov edi, [.first_range] |
9715 | Doczom | 500 | cmp dword [edi + mtrr_range.start], eax |
4608 | clevermous | 501 | jnz .abort |
9715 | Doczom | 502 | cmp dword [edi + mtrr_range.start+4], eax |
4608 | clevermous | 503 | jnz .abort |
9715 | Doczom | 504 | cmp dword [edi + mtrr_range.length+4], eax |
4608 | clevermous | 505 | jnz .abort |
9715 | Doczom | 506 | mov edx, [edi + mtrr_range.next] |
4608 | clevermous | 507 | test edx, edx |
508 | jz @f |
||
9715 | Doczom | 509 | cmp dword [edx + mtrr_range.start], eax |
4608 | clevermous | 510 | jnz .abort |
9715 | Doczom | 511 | cmp dword [edx + mtrr_range.start+4], 1 |
4608 | clevermous | 512 | jnz .abort |
9715 | Doczom | 513 | cmp [edx + mtrr_range.next], eax |
4608 | clevermous | 514 | jnz .abort |
3166 | clevermous | 515 | @@: |
4608 | clevermous | 516 | ; 8b. Initialize: no MTRRs filled. |
517 | mov [.num_used_mtrrs], eax |
||
518 | lea esi, [.mtrrs] |
||
519 | .range2mtrr_loop: |
||
520 | ; 8c. If we are dealing with upper-memory range (after 4G) |
||
521 | ; with length > start, create one WB MTRR with [start,2*start), |
||
522 | ; reset start to 2*start and return to this step. |
||
523 | ; Example: [4G,24G) -> [4G,8G) {returning} + [8G,16G) {returning} |
||
524 | ; + [16G,24G) {advancing to ?}. |
||
9715 | Doczom | 525 | mov eax, dword [edi + mtrr_range.length+4] |
2288 | clevermous | 526 | test eax, eax |
4608 | clevermous | 527 | jz .less4G |
9715 | Doczom | 528 | mov edx, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 529 | cmp eax, edx |
530 | jb .start_aligned |
||
531 | inc [.num_used_mtrrs] |
||
532 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
533 | ja .abort |
||
534 | mov dword [esi], MEM_WB |
||
535 | mov dword [esi+4], edx |
||
536 | mov dword [esi+8], 0 |
||
537 | mov dword [esi+12], edx |
||
538 | add esi, 16 |
||
9715 | Doczom | 539 | add dword [edi + mtrr_range.start+4], edx |
540 | sub dword [edi + mtrr_range.length+4], edx |
||
4608 | clevermous | 541 | jnz .range2mtrr_loop |
9715 | Doczom | 542 | cmp dword [edi + mtrr_range.length], 0 |
4608 | clevermous | 543 | jz .range2mtrr_next |
544 | .less4G: |
||
545 | ; 8d. If we are dealing with low-memory range (before 4G) |
||
546 | ; and appending a maximal-size hole would create a range covering top of 4G, |
||
547 | ; create a maximal-size WB range and return to this step. |
||
548 | ; Example: for [0,0xBC000000) the following steps would consider |
||
549 | ; variants [0,0x80000000)+(another range to be splitted) and |
||
550 | ; [0,0x100000000)-(another range to be splitted); we forbid the last variant, |
||
551 | ; so the first variant must be used. |
||
9715 | Doczom | 552 | bsr ecx, dword [edi + mtrr_range.length] |
4608 | clevermous | 553 | xor edx, edx |
554 | inc edx |
||
555 | shl edx, cl |
||
556 | lea eax, [edx*2] |
||
9715 | Doczom | 557 | add eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 558 | jnz .start_aligned |
559 | inc [.num_used_mtrrs] |
||
560 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
561 | ja .abort |
||
9715 | Doczom | 562 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 563 | mov dword [esi], eax |
564 | or dword [esi], MEM_WB |
||
565 | mov dword [esi+4], 0 |
||
566 | mov dword [esi+8], edx |
||
567 | mov dword [esi+12], 0 |
||
568 | add esi, 16 |
||
9715 | Doczom | 569 | add dword [edi + mtrr_range.start], edx |
570 | sub dword [edi + mtrr_range.length], edx |
||
4608 | clevermous | 571 | jnz .less4G |
572 | jmp .range2mtrr_next |
||
573 | .start_aligned: |
||
574 | ; Start is aligned for any allowed length, maximum-size hole is allowed. |
||
575 | ; Select the best MTRR configuration for one range. |
||
576 | ; length=...101101 |
||
577 | ; Without hole at the end, we need one WB MTRR for every 1-bit in length: |
||
578 | ; length=...100000 + ...001000 + ...000100 + ...000001 |
||
579 | ; We can also append one hole at the end so that one 0-bit (selected by us) |
||
580 | ; becomes 1 and all lower bits become 0 for WB-range: |
||
581 | ; length=...110000 - (...00010 + ...00001) |
||
582 | ; In this way, we need one WB MTRR for every 1-bit higher than the selected bit, |
||
583 | ; one WB MTRR for the selected bit, one UC MTRR for every 0-bit between |
||
584 | ; the selected bit and lowest 1-bit (they become 1-bits after negation) |
||
585 | ; and one UC MTRR for lowest 1-bit. |
||
586 | ; So we need to select 0-bit with the maximal difference |
||
587 | ; (number of 0-bits) - (number of 1-bits) between selected and lowest 1-bit, |
||
588 | ; this equals the gain from using a hole. If the difference is negative for |
||
589 | ; all 0-bits, don't append hole. |
||
590 | ; Note that lowest 1-bit is not included when counting, but selected 0-bit is. |
||
591 | ; 8e. Find the optimal bit position for hole. |
||
592 | ; eax = current difference, ebx = best difference, |
||
593 | ; ecx = hole bit position, edx = current bit position. |
||
2288 | clevermous | 594 | xor eax, eax |
4608 | clevermous | 595 | xor ebx, ebx |
596 | xor ecx, ecx |
||
9715 | Doczom | 597 | bsf edx, dword [edi + mtrr_range.length] |
4608 | clevermous | 598 | jnz @f |
9715 | Doczom | 599 | bsf edx, dword [edi + mtrr_range.length+4] |
4608 | clevermous | 600 | add edx, 32 |
2288 | clevermous | 601 | @@: |
4608 | clevermous | 602 | push edx ; save position of lowest 1-bit for step 8f |
603 | .calc_stat: |
||
2288 | clevermous | 604 | inc edx |
4608 | clevermous | 605 | cmp edx, 64 |
606 | jae .stat_done |
||
607 | inc eax ; increment difference in hope for 1-bit |
||
608 | ; Note: bt conveniently works with both .length and .length+4, |
||
609 | ; depending on whether edx>=32. |
||
9715 | Doczom | 610 | bt dword [edi + mtrr_range.length], edx |
4608 | clevermous | 611 | jc .calc_stat |
612 | dec eax ; hope was wrong, decrement difference to correct 'inc' |
||
613 | dec eax ; and again, now getting the real difference |
||
614 | cmp eax, ebx |
||
615 | jle .calc_stat |
||
616 | mov ebx, eax |
||
617 | mov ecx, edx |
||
618 | jmp .calc_stat |
||
619 | .stat_done: |
||
620 | ; 8f. If we decided to create a hole, flip all bits between lowest and selected. |
||
621 | pop edx ; restore position of lowest 1-bit saved at step 8e |
||
622 | test ecx, ecx |
||
623 | jz .fill_hi_init |
||
2288 | clevermous | 624 | @@: |
625 | inc edx |
||
4608 | clevermous | 626 | cmp edx, ecx |
627 | ja .fill_hi_init |
||
9715 | Doczom | 628 | btc dword [edi + mtrr_range.length], edx |
4608 | clevermous | 629 | jmp @b |
630 | .fill_hi_init: |
||
631 | ; 8g. Create MTRR ranges corresponding to upper 32 bits. |
||
632 | sub ecx, 32 |
||
633 | .fill_hi_loop: |
||
9715 | Doczom | 634 | bsr edx, dword [edi + mtrr_range.length+4] |
4608 | clevermous | 635 | jz .fill_hi_done |
636 | inc [.num_used_mtrrs] |
||
637 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
638 | ja .abort |
||
9715 | Doczom | 639 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 640 | mov [esi], eax |
9715 | Doczom | 641 | mov eax, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 642 | mov [esi+4], eax |
643 | xor eax, eax |
||
644 | mov [esi+8], eax |
||
645 | bts eax, edx |
||
646 | mov [esi+12], eax |
||
647 | cmp edx, ecx |
||
648 | jl .fill_hi_uc |
||
649 | or dword [esi], MEM_WB |
||
9715 | Doczom | 650 | add dword [edi + mtrr_range.start+4], eax |
4608 | clevermous | 651 | jmp @f |
652 | .fill_hi_uc: |
||
653 | sub dword [esi+4], eax |
||
9715 | Doczom | 654 | sub dword [edi + mtrr_range.start+4], eax |
2288 | clevermous | 655 | @@: |
4608 | clevermous | 656 | add esi, 16 |
9715 | Doczom | 657 | sub dword [edi + mtrr_range.length], eax |
4608 | clevermous | 658 | jmp .fill_hi_loop |
659 | .fill_hi_done: |
||
660 | ; 8h. Create MTRR ranges corresponding to lower 32 bits. |
||
661 | add ecx, 32 |
||
662 | .fill_lo_loop: |
||
663 | bsr edx, dword [edi+mtrr_range.length] |
||
664 | jz .range2mtrr_next |
||
665 | inc [.num_used_mtrrs] |
||
666 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
667 | ja .abort |
||
9715 | Doczom | 668 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 669 | mov [esi], eax |
9715 | Doczom | 670 | mov eax, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 671 | mov [esi+4], eax |
672 | xor eax, eax |
||
673 | mov [esi+12], eax |
||
674 | bts eax, edx |
||
675 | mov [esi+8], eax |
||
676 | cmp edx, ecx |
||
677 | jl .fill_lo_uc |
||
678 | or dword [esi], MEM_WB |
||
9715 | Doczom | 679 | add dword [edi + mtrr_range.start], eax |
4608 | clevermous | 680 | jmp @f |
681 | .fill_lo_uc: |
||
682 | sub dword [esi], eax |
||
9715 | Doczom | 683 | sub dword [edi + mtrr_range.start], eax |
2288 | clevermous | 684 | @@: |
4608 | clevermous | 685 | add esi, 16 |
9715 | Doczom | 686 | sub dword [edi + mtrr_range.length], eax |
4608 | clevermous | 687 | jmp .fill_lo_loop |
688 | .range2mtrr_next: |
||
689 | ; 8i. Repeat the loop at 8c-8h for all ranges. |
||
9715 | Doczom | 690 | mov edi, [edi + mtrr_range.next] |
2288 | clevermous | 691 | test edi, edi |
4608 | clevermous | 692 | jnz .range2mtrr_loop |
693 | ; 9. We have calculated needed MTRRs, now setup them in the CPU. |
||
694 | ; 9a. Abort if number of MTRRs is too large. |
||
695 | mov eax, [num_variable_mtrrs] |
||
696 | cmp [.num_used_mtrrs], eax |
||
697 | ja .abort |
||
2288 | clevermous | 698 | |
4608 | clevermous | 699 | ; 9b. Prepare for changes. |
700 | call mtrr_begin_change |
||
2288 | clevermous | 701 | |
4608 | clevermous | 702 | ; 9c. Prepare for loop over MTRRs. |
703 | lea esi, [.mtrrs] |
||
704 | mov ecx, 0x200 |
||
2288 | clevermous | 705 | @@: |
4608 | clevermous | 706 | ; 9d. For every MTRR, copy PHYSBASEn as is: step 8 has configured |
707 | ; start value and type bits as needed. |
||
708 | mov eax, [esi] |
||
709 | mov edx, [esi+4] |
||
710 | wrmsr |
||
711 | inc ecx |
||
712 | ; 9e. For every MTRR, calculate PHYSMASKn = -(length) or 0x800 |
||
713 | ; with upper bits cleared, 0x800 = MTRR is valid. |
||
2288 | clevermous | 714 | xor eax, eax |
715 | xor edx, edx |
||
4608 | clevermous | 716 | sub eax, [esi+8] |
717 | sbb edx, [esi+12] |
||
718 | or eax, 0x800 |
||
719 | or edx, [.phys_reserved_mask] |
||
720 | xor edx, [.phys_reserved_mask] |
||
2288 | clevermous | 721 | wrmsr |
722 | inc ecx |
||
4608 | clevermous | 723 | ; 9f. Continue steps 9d and 9e for all MTRRs calculated at step 8. |
724 | add esi, 16 |
||
725 | dec [.num_used_mtrrs] |
||
726 | jnz @b |
||
727 | ; 9g. Zero other MTRRs. |
||
2288 | clevermous | 728 | xor eax, eax |
729 | xor edx, edx |
||
4608 | clevermous | 730 | mov ebx, [num_variable_mtrrs] |
731 | lea ebx, [0x200+ebx*2] |
||
2288 | clevermous | 732 | @@: |
4608 | clevermous | 733 | cmp ecx, ebx |
734 | jae @f |
||
735 | wrmsr |
||
4418 | clevermous | 736 | inc ecx |
2288 | clevermous | 737 | wrmsr |
4608 | clevermous | 738 | inc ecx |
739 | jmp @b |
||
740 | @@: |
||
741 | |||
5360 | serge | 742 | ; 9i. Check PAT support and reprogram PAT_MASR for write combining memory |
743 | bt [cpu_caps], CAPS_PAT |
||
744 | jnc @F |
||
745 | |||
746 | mov ecx, MSR_CR_PAT |
||
747 | mov eax, PAT_VALUE ;UC UCM WC WB |
||
748 | mov edx, eax |
||
2288 | clevermous | 749 | wrmsr |
5360 | serge | 750 | @@: |
2288 | clevermous | 751 | |
4608 | clevermous | 752 | ; 9j. Changes are done. |
753 | call mtrr_end_change |
||
2288 | clevermous | 754 | |
4608 | clevermous | 755 | .abort: |
756 | add esp, .local_vars_size + MAX_RANGES * sizeof.mtrr_range |
||
757 | pop ebp |
||
2288 | clevermous | 758 | ret |
759 | endp |
||
760 | |||
4608 | clevermous | 761 | ; Allocate&set one MTRR for given range. |
762 | ; size must be power of 2 that divides base. |
||
2288 | clevermous | 763 | proc set_mtrr stdcall, base:dword,size:dword,mem_type:dword |
764 | ; find unused register |
||
765 | mov ecx, 0x201 |
||
4608 | clevermous | 766 | .scan: |
6721 | clevermous | 767 | mov eax, [num_variable_mtrrs] |
768 | lea eax, [0x200+eax*2] |
||
769 | cmp ecx, eax |
||
770 | jae .ret |
||
2288 | clevermous | 771 | rdmsr |
772 | dec ecx |
||
773 | test ah, 8 |
||
774 | jz .found |
||
775 | rdmsr |
||
4608 | clevermous | 776 | test edx, edx |
777 | jnz @f |
||
778 | and eax, not 0xFFF ; clear reserved bits |
||
2288 | clevermous | 779 | cmp eax, [base] |
780 | jz .ret |
||
4608 | clevermous | 781 | @@: |
2288 | clevermous | 782 | add ecx, 3 |
6721 | clevermous | 783 | jmp .scan |
2288 | clevermous | 784 | ; no free registers, ignore the call |
785 | .ret: |
||
786 | ret |
||
787 | .found: |
||
788 | ; found, write values |
||
5360 | serge | 789 | push ecx |
4608 | clevermous | 790 | call mtrr_begin_change |
5360 | serge | 791 | pop ecx |
2288 | clevermous | 792 | xor edx, edx |
793 | mov eax, [base] |
||
794 | or eax, [mem_type] |
||
795 | wrmsr |
||
796 | |||
4608 | clevermous | 797 | mov al, [cpu_phys_addr_width] |
798 | xor edx, edx |
||
799 | bts edx, eax |
||
800 | xor eax, eax |
||
801 | sub eax, [size] |
||
2288 | clevermous | 802 | sbb edx, 0 |
803 | or eax, 0x800 |
||
804 | inc ecx |
||
805 | wrmsr |
||
4608 | clevermous | 806 | call mtrr_end_change |
2288 | clevermous | 807 | ret |
808 | endp |
||
809 | |||
4608 | clevermous | 810 | ; Helper procedure for mtrr_validate. |
811 | ; Calculates memory type for given address according to variable-range MTRRs. |
||
812 | ; Assumes that MTRRs are enabled. |
||
813 | ; in: ebx = 32-bit physical address |
||
814 | ; out: eax = memory type for ebx |
||
815 | proc mtrr_get_real_type |
||
816 | ; 1. Initialize: we have not yet found any MTRRs covering ebx. |
||
817 | push 0 |
||
818 | mov ecx, 0x201 |
||
819 | .mtrr_loop: |
||
820 | ; 2. For every MTRR, check whether it is valid; if not, continue to the next MTRR. |
||
821 | rdmsr |
||
2288 | clevermous | 822 | dec ecx |
4608 | clevermous | 823 | test ah, 8 |
824 | jz .next |
||
825 | ; 3. For every valid MTRR, check whether (ebx and PHYSMASKn) == PHYSBASEn, |
||
826 | ; excluding low 12 bits. |
||
827 | and eax, ebx |
||
828 | push eax |
||
829 | rdmsr |
||
830 | test edx, edx |
||
831 | pop edx |
||
832 | jnz .next |
||
833 | xor edx, eax |
||
834 | and edx, not 0xFFF |
||
835 | jnz .next |
||
836 | ; 4. If so, set the bit corresponding to memory type defined by this MTRR. |
||
837 | and eax, 7 |
||
838 | bts [esp], eax |
||
839 | .next: |
||
840 | ; 5. Continue loop at 2-4 for all variable-range MTRRs. |
||
841 | add ecx, 3 |
||
842 | mov eax, [num_variable_mtrrs] |
||
843 | lea eax, [0x200+eax*2] |
||
844 | cmp ecx, eax |
||
845 | jb .mtrr_loop |
||
846 | ; 6. If no MTRRs cover address in ebx, use default MTRR type from MTRR_DEF_CAP. |
||
847 | pop edx |
||
848 | test edx, edx |
||
849 | jz .default |
||
850 | ; 7. Find&clear 1-bit in edx. |
||
851 | bsf eax, edx |
||
852 | btr edx, eax |
||
853 | ; 8. If there was only one 1-bit, then all MTRRs are consistent, return that bit. |
||
854 | test edx, edx |
||
855 | jz .nothing |
||
856 | ; Otherwise, return MEM_UC (e.g. WB+UC is UC). |
||
2288 | clevermous | 857 | xor eax, eax |
4608 | clevermous | 858 | .nothing: |
2288 | clevermous | 859 | ret |
4608 | clevermous | 860 | .default: |
861 | mov ecx, 0x2FF |
||
862 | rdmsr |
||
863 | movzx eax, al |
||
864 | ret |
||
2288 | clevermous | 865 | endp |
2466 | Serge | 866 | |
4608 | clevermous | 867 | ; If MTRRs are configured improperly, this is not obvious to the user; |
868 | ; everything works, but the performance can be horrible. |
||
869 | ; Try to detect this and let the user know that the low performance |
||
870 | ; is caused by some problem and is not a global property of the system. |
||
871 | ; Let's hope he would report it to developers... |
||
872 | proc mtrr_validate |
||
873 | ; 1. If MTRRs are not supported, they cannot be configured improperly. |
||
4619 | clevermous | 874 | ; Note: VirtualBox claims MTRR support in cpuid, but emulates MTRRCAP=0, |
875 | ; which is efficiently equivalent to absent MTRRs. |
||
876 | ; So check [num_variable_mtrrs] instead of CAPS_MTRR in [cpu_caps]. |
||
877 | cmp [num_variable_mtrrs], 0 |
||
878 | jz .exit |
||
4608 | clevermous | 879 | ; 2. If variable-range MTRRs are not configured, this is a problem. |
880 | mov ecx, 0x2FF |
||
881 | rdmsr |
||
882 | test ah, 8 |
||
883 | jz .fail |
||
884 | ; 3. Get the memory type for address somewhere inside working memory. |
||
885 | ; It must be write-back. |
||
886 | mov ebx, 0x27FFFF |
||
887 | call mtrr_get_real_type |
||
888 | cmp al, MEM_WB |
||
889 | jnz .fail |
||
890 | ; 4. If we're using a mode with LFB, |
||
891 | ; get the memory type for last pixel of the framebuffer. |
||
892 | ; It must be write-combined. |
||
893 | test word [SCR_MODE], 0x4000 |
||
894 | jz .exit |
||
5351 | serge | 895 | mov eax, [_display.lfb_pitch] |
4608 | clevermous | 896 | mul [_display.height] |
897 | dec eax |
||
898 | ; LFB is mapped to virtual address LFB_BASE, |
||
899 | ; it uses global pages if supported by CPU. |
||
9715 | Doczom | 900 | mov ebx, [sys_proc + PROC.pdt_0 + (LFB_BASE shr 20)] |
5356 | serge | 901 | test ebx, PDE_LARGE |
4608 | clevermous | 902 | jnz @f |
903 | mov ebx, [page_tabs+(LFB_BASE shr 10)] |
||
2466 | Serge | 904 | @@: |
4608 | clevermous | 905 | and ebx, not 0xFFF |
906 | add ebx, eax |
||
907 | call mtrr_get_real_type |
||
908 | cmp al, MEM_WC |
||
909 | jz .exit |
||
910 | ; 5. The check at step 4 fails on Bochs: |
||
911 | ; Bochs BIOS configures MTRRs in a strange way not respecting [cpu_phys_addr_width], |
||
912 | ; so mtrr_reconfigure avoids to touch anything. |
||
913 | ; However, Bochs core ignores MTRRs (keeping them only for rdmsr/wrmsr), |
||
914 | ; so we don't care about proper setting for Bochs. |
||
915 | ; Use northbridge PCI id to detect Bochs: it emulates either i440fx or i430fx |
||
916 | ; depending on configuration file. |
||
917 | mov eax, [pcidev_list.fd] |
||
918 | cmp eax, pcidev_list ; sanity check: fail if no PCI devices |
||
919 | jz .fail |
||
9715 | Doczom | 920 | cmp [eax + PCIDEV.vendor_device_id], 0x12378086 |
4608 | clevermous | 921 | jz .exit |
9715 | Doczom | 922 | cmp [eax + PCIDEV.vendor_device_id], 0x01228086 |
4608 | clevermous | 923 | jnz .fail |
924 | .exit: |
||
2466 | Serge | 925 | ret |
4608 | clevermous | 926 | .fail: |
927 | mov ebx, mtrr_user_message |
||
928 | mov ebp, notifyapp |
||
929 | call fs_execute_from_sysdir_param |
||
930 | ret |
||
2466 | Serge | 931 | endp |