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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: 9950 $ |
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9 | |||
9950 | turbocat | 10 | ; Initializes PAT (Page Attribute Table) and MTRRs. |
11 | proc init_pat_mtrr |
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7132 | dunkaist | 12 | cmp [BOOT.mtrr], byte 2 |
4608 | clevermous | 13 | je .exit |
2288 | clevermous | 14 | |
9950 | turbocat | 15 | bt [cpu_caps], CAPS_PAT ; if PAT is not supported, use MTRR |
16 | jnc .use_mtrr |
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17 | |||
18 | ; Change PAT_MSR for write combining memory. |
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19 | mov ecx, MSR_CR_PAT |
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20 | mov eax, PAT_VALUE ; UC UCM WC WB |
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21 | mov edx, eax |
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22 | wrmsr |
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23 | ret |
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24 | |||
25 | .use_mtrr: |
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4608 | clevermous | 26 | bt [cpu_caps], CAPS_MTRR |
27 | jnc .exit |
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2288 | clevermous | 28 | |
4608 | clevermous | 29 | call mtrr_reconfigure |
30 | stdcall set_mtrr, [LFBAddress], 0x1000000, MEM_WC |
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2288 | clevermous | 31 | |
4608 | clevermous | 32 | .exit: |
2288 | clevermous | 33 | ret |
34 | endp |
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35 | |||
4608 | clevermous | 36 | ; Helper procedure for mtrr_reconfigure and set_mtrr, |
37 | ; called before changes in MTRRs. |
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5360 | serge | 38 | ; 1. disable and flush caches |
39 | ; 2. clear PGE bit in cr4 |
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40 | ; 3. flush TLB |
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41 | ; 4. disable mtrr |
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42 | |||
4608 | clevermous | 43 | proc mtrr_begin_change |
44 | mov eax, cr0 |
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45 | or eax, 0x60000000 ;disable caching |
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46 | mov cr0, eax |
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47 | wbinvd ;invalidate cache |
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5360 | serge | 48 | |
49 | bt [cpu_caps], CAPS_PGE |
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50 | jnc .cr3_flush |
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51 | |||
52 | mov eax, cr4 |
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53 | btr eax, 7 ;clear cr4.PGE |
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54 | mov cr4, eax ;flush TLB |
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55 | jmp @F ;skip extra serialization |
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56 | |||
57 | .cr3_flush: |
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58 | mov eax, cr3 |
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59 | mov cr3, eax ;flush TLB |
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60 | @@: |
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61 | mov ecx, MSR_MTRR_DEF_TYPE |
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62 | rdmsr |
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63 | btr eax, 11 ;clear enable flag |
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64 | wrmsr ;disable mtrr |
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2288 | clevermous | 65 | ret |
66 | endp |
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67 | |||
4608 | clevermous | 68 | ; Helper procedure for mtrr_reconfigure and set_mtrr, |
69 | ; called after changes in MTRRs. |
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5360 | serge | 70 | ; 1. enable mtrr |
71 | ; 2. flush all caches |
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72 | ; 3. flush TLB |
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73 | ; 4. restore cr4.PGE flag, if required |
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74 | |||
4608 | clevermous | 75 | proc mtrr_end_change |
5360 | serge | 76 | mov ecx, MSR_MTRR_DEF_TYPE |
77 | rdmsr |
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78 | or ah, 8 ; enable variable-ranges MTRR |
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79 | and al, 0xF0 ; default memtype = UC |
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80 | wrmsr |
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81 | |||
4608 | clevermous | 82 | wbinvd ;again invalidate |
83 | mov eax, cr0 |
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84 | and eax, not 0x60000000 |
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85 | mov cr0, eax ; enable caching |
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5360 | serge | 86 | |
87 | mov eax, cr3 |
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88 | mov cr3, eax ;flush tlb |
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89 | |||
90 | bt [cpu_caps], CAPS_PGE |
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91 | jnc @F |
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92 | |||
93 | mov eax, cr4 |
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94 | bts eax, 7 ;set cr4.PGE flag |
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95 | mov cr4, eax |
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96 | @@: |
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2288 | clevermous | 97 | ret |
98 | endp |
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99 | |||
4608 | clevermous | 100 | ; Some limits to number of structures located in the stack. |
101 | MAX_USEFUL_MTRRS = 16 |
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102 | MAX_RANGES = 16 |
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2288 | clevermous | 103 | |
4608 | clevermous | 104 | ; mtrr_reconfigure keeps a list of MEM_WB ranges. |
105 | ; This structure describes one item in the list. |
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106 | struct mtrr_range |
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107 | next dd ? ; next item |
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108 | start dq ? ; first byte |
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109 | length dq ? ; length in bytes |
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110 | ends |
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2288 | clevermous | 111 | |
4608 | clevermous | 112 | uglobal |
2288 | clevermous | 113 | align 4 |
4608 | clevermous | 114 | num_variable_mtrrs dd 0 ; number of variable-range MTRRs |
115 | endg |
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2288 | clevermous | 116 | |
4608 | clevermous | 117 | ; Helper procedure for MTRR initialization. |
118 | ; Takes MTRR configured by BIOS and tries to recongifure them |
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119 | ; in order to allow non-UC data at top of 4G memory. |
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120 | ; Example: if low part of physical memory is 3.5G = 0xE0000000 bytes wide, |
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121 | ; BIOS can configure two MTRRs so that the first MTRR describes [0, 4G) as WB |
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122 | ; and the second MTRR describes [3.5G, 4G) as UC; |
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123 | ; WB+UC=UC, so the resulting memory map would be as needed, |
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124 | ; but in this configuration our attempts to map LFB at (say) 0xE8000000 as WC |
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125 | ; would be ignored, WB+UC+WC is still UC. |
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126 | ; So we must keep top of 4G memory not covered by MTRRs, |
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127 | ; using three WB MTRRs [0,2G) + [2G,3G) + [3G,3.5G), |
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128 | ; this gives the same memory map, but allows to add further entries. |
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129 | ; See mtrrtest.asm for detailed input/output from real hardware+BIOS. |
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130 | proc mtrr_reconfigure |
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131 | push ebp ; we're called from init_LFB, and it feels hurt when ebp is destroyed |
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132 | ; 1. Prepare local variables. |
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133 | ; 1a. Create list of MAX_RANGES free (aka not yet allocated) ranges. |
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2288 | clevermous | 134 | xor eax, eax |
9715 | Doczom | 135 | lea ecx, [eax + MAX_RANGES] |
4608 | clevermous | 136 | .init_ranges: |
137 | sub esp, sizeof.mtrr_range - 4 |
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138 | push eax |
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139 | mov eax, esp |
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140 | dec ecx |
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141 | jnz .init_ranges |
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142 | mov eax, esp |
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143 | ; 1b. Fill individual local variables. |
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144 | xor edx, edx |
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145 | sub esp, MAX_USEFUL_MTRRS * 16 ; .mtrrs |
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146 | push edx ; .mtrrs_end |
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147 | push edx ; .num_used_mtrrs |
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148 | push eax ; .first_free_range |
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149 | push edx ; .first_range: no ranges yet |
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150 | mov cl, [cpu_phys_addr_width] |
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151 | or eax, -1 |
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152 | shl eax, cl ; note: this uses cl&31 = cl-32, not the entire cl |
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153 | push eax ; .phys_reserved_mask |
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154 | virtual at esp |
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155 | .phys_reserved_mask dd ? |
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156 | .first_range dd ? |
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157 | .first_free_range dd ? |
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158 | .num_used_mtrrs dd ? |
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159 | .mtrrs_end dd ? |
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160 | .mtrrs rq MAX_USEFUL_MTRRS * 2 |
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161 | .local_vars_size = $ - esp |
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162 | end virtual |
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2288 | clevermous | 163 | |
4608 | clevermous | 164 | ; 2. Get the number of variable-range MTRRs from MTRRCAP register. |
165 | ; Abort if zero. |
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166 | mov ecx, 0xFE |
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167 | rdmsr |
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168 | test al, al |
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169 | jz .abort |
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170 | mov byte [num_variable_mtrrs], al |
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171 | ; 3. Validate MTRR_DEF_TYPE register. |
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172 | mov ecx, 0x2FF |
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173 | rdmsr |
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174 | ; If BIOS has not initialized variable-range MTRRs, fallback to step 7. |
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175 | test ah, 8 |
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176 | jz .fill_ranges_from_memory_map |
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177 | ; If the default memory type (not covered by MTRRs) is not UC, |
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178 | ; then probably BIOS did something strange, so it is better to exit immediately |
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179 | ; hoping for the best. |
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180 | cmp al, MEM_UC |
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181 | jnz .abort |
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182 | ; 4. Validate all variable-range MTRRs |
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183 | ; and copy configured MTRRs to the local array [.mtrrs]. |
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184 | ; 4a. Prepare for the loop over existing variable-range MTRRs. |
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185 | mov ecx, 0x200 |
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186 | lea edi, [.mtrrs] |
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187 | .get_used_mtrrs_loop: |
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188 | ; 4b. For every MTRR, read PHYSBASEn and PHYSMASKn. |
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189 | ; In PHYSBASEn, clear upper bits and copy to ebp:ebx. |
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190 | rdmsr |
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191 | or edx, [.phys_reserved_mask] |
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192 | xor edx, [.phys_reserved_mask] |
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193 | mov ebp, edx |
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2288 | clevermous | 194 | mov ebx, eax |
4608 | clevermous | 195 | inc ecx |
196 | ; If PHYSMASKn is not active, ignore this MTRR. |
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197 | rdmsr |
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198 | inc ecx |
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199 | test ah, 8 |
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200 | jz .get_used_mtrrs_next |
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201 | ; 4c. For every active MTRR, check that number of local entries is not too large. |
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202 | inc [.num_used_mtrrs] |
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203 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
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204 | ja .abort |
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205 | ; 4d. For every active MTRR, store PHYSBASEn with upper bits cleared. |
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206 | ; This contains the MTRR base and the memory type in low byte. |
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207 | mov [edi], ebx |
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208 | mov [edi+4], ebp |
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209 | ; 4e. For every active MTRR, check that the range is continuous: |
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210 | ; PHYSMASKn with upper bits set must be negated power of two, and |
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211 | ; low bits of PHYSBASEn must be zeroes: |
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212 | ; PHYSMASKn = 1...10...0, |
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213 | ; PHYSBASEn = x...x0...0, |
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214 | ; this defines a continuous range from x...x0...0 to x...x1...1, |
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215 | ; length = 10...0 = negated PHYSMASKn. |
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216 | ; Store length in the local array. |
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217 | and eax, not 0xFFF |
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218 | or edx, [.phys_reserved_mask] |
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219 | mov dword [edi+8], 0 |
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220 | mov dword [edi+12], 0 |
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221 | sub [edi+8], eax |
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222 | sbb [edi+12], edx |
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223 | ; (x and -x) is the maximum power of two that divides x. |
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224 | ; Condition for powers of two: (x and -x) equals x. |
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225 | and eax, [edi+8] |
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226 | and edx, [edi+12] |
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227 | cmp eax, [edi+8] |
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228 | jnz .abort |
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229 | cmp edx, [edi+12] |
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230 | jnz .abort |
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231 | sub eax, 1 |
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232 | sbb edx, 0 |
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233 | and eax, not 0xFFF |
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234 | and eax, ebx |
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235 | jnz .abort |
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236 | and edx, ebp |
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237 | jnz .abort |
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238 | ; 4f. For every active MTRR, validate memory type: it must be either WB or UC. |
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239 | add edi, 16 |
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240 | cmp bl, MEM_UC |
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241 | jz .get_used_mtrrs_next |
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242 | cmp bl, MEM_WB |
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243 | jnz .abort |
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244 | .get_used_mtrrs_next: |
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245 | ; 4g. Repeat the loop at 4b-4f for all [num_variable_mtrrs] entries. |
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246 | mov eax, [num_variable_mtrrs] |
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247 | lea eax, [0x200+eax*2] |
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248 | cmp ecx, eax |
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249 | jb .get_used_mtrrs_loop |
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250 | ; 4h. If no active MTRRs were detected, fallback to step 7. |
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251 | cmp [.num_used_mtrrs], 0 |
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252 | jz .fill_ranges_from_memory_map |
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253 | mov [.mtrrs_end], edi |
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254 | ; 5. Generate sorted list of ranges marked as WB. |
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255 | ; 5a. Prepare for the loop over configured MTRRs filled at step 4. |
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256 | lea ecx, [.mtrrs] |
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257 | .fill_wb_ranges: |
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258 | ; 5b. Ignore non-WB MTRRs. |
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259 | mov ebx, [ecx] |
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260 | cmp bl, MEM_WB |
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261 | jnz .next_wb_range |
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262 | mov ebp, [ecx+4] |
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263 | and ebx, not 0xFFF ; clear memory type and reserved bits |
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264 | ; ebp:ebx = start of the range described by the current MTRR. |
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265 | ; 5c. Find the first existing range containing a point greater than ebp:ebx. |
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266 | lea esi, [.first_range] |
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267 | .find_range_wb: |
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268 | ; If there is no next range or start of the next range is greater than ebp:ebx, |
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269 | ; exit the loop to 5d. |
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270 | mov edi, [esi] |
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271 | test edi, edi |
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272 | jz .found_place_wb |
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273 | mov eax, ebx |
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274 | mov edx, ebp |
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9715 | Doczom | 275 | sub eax, dword [edi + mtrr_range.start] |
276 | sbb edx, dword [edi + mtrr_range.start+4] |
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4608 | clevermous | 277 | jb .found_place_wb |
278 | ; Otherwise, if end of the next range is greater than or equal to ebp:ebx, |
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279 | ; exit the loop to 5e. |
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280 | mov esi, edi |
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9715 | Doczom | 281 | sub eax, dword [edi + mtrr_range.length] |
282 | sbb edx, dword [edi + mtrr_range.length+4] |
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4608 | clevermous | 283 | jb .expand_wb |
284 | or eax, edx |
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285 | jnz .find_range_wb |
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286 | jmp .expand_wb |
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287 | .found_place_wb: |
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288 | ; 5d. ebp:ebx is not within any existing range. |
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289 | ; Insert a new range between esi and edi. |
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290 | ; (Later, during 5e, it can be merged with the following ranges.) |
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291 | mov eax, [.first_free_range] |
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292 | test eax, eax |
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293 | jz .abort |
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294 | mov [esi], eax |
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9715 | Doczom | 295 | mov edx, [eax + mtrr_range.next] |
4608 | clevermous | 296 | mov [.first_free_range], edx |
9715 | Doczom | 297 | mov dword [eax + mtrr_range.start], ebx |
298 | mov dword [eax + mtrr_range.start+4], ebp |
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4608 | clevermous | 299 | ; Don't fill [eax+mtrr_range.next] and [eax+mtrr_range.length] yet, |
300 | ; they will be calculated including merges at step 5e. |
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301 | mov esi, edi |
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2288 | clevermous | 302 | mov edi, eax |
4608 | clevermous | 303 | .expand_wb: |
304 | ; 5e. The range at edi contains ebp:ebx, and esi points to the first range |
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305 | ; to be checked for merge: esi=edi if ebp:ebx was found in an existing range, |
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306 | ; esi is next after edi if a new range with ebp:ebx was created. |
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307 | ; Merge it with following ranges while start of the next range is not greater |
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308 | ; than the end of the new range. |
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309 | add ebx, [ecx+8] |
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310 | adc ebp, [ecx+12] |
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311 | ; ebp:ebx = end of the range described by the current MTRR. |
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312 | .expand_wb_loop: |
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313 | ; If there is no next range or start of the next range is greater than ebp:ebx, |
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314 | ; exit the loop to 5g. |
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315 | test esi, esi |
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316 | jz .expand_wb_done |
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317 | mov eax, ebx |
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318 | mov edx, ebp |
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9715 | Doczom | 319 | sub eax, dword [esi + mtrr_range.start] |
320 | sbb edx, dword [esi + mtrr_range.start+4] |
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4608 | clevermous | 321 | jb .expand_wb_done |
322 | ; Otherwise, if end of the next range is greater than or equal to ebp:ebx, |
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323 | ; exit the loop to 5f. |
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9715 | Doczom | 324 | sub eax, dword [esi + mtrr_range.length] |
325 | sbb edx, dword [esi + mtrr_range.length+4] |
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4608 | clevermous | 326 | jb .expand_wb_last |
327 | ; Otherwise, the current range is completely within the new range. |
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328 | ; Free it and continue the loop. |
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9715 | Doczom | 329 | mov edx, [esi + mtrr_range.next] |
4608 | clevermous | 330 | cmp esi, edi |
331 | jz @f |
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332 | mov eax, [.first_free_range] |
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9715 | Doczom | 333 | mov [esi + mtrr_range.next], eax |
4608 | clevermous | 334 | mov [.first_free_range], esi |
2288 | clevermous | 335 | @@: |
4608 | clevermous | 336 | mov esi, edx |
337 | jmp .expand_wb_loop |
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338 | .expand_wb_last: |
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339 | ; 5f. Start of the new range is inside range described by esi, |
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340 | ; end of the new range is inside range described by edi. |
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341 | ; If esi is equal to edi, the new range is completely within |
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342 | ; an existing range, so proceed to the next range. |
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343 | cmp esi, edi |
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344 | jz .next_wb_range |
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345 | ; Otherwise, set end of interval at esi to end of interval at edi |
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346 | ; and free range described by edi. |
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9715 | Doczom | 347 | mov ebx, dword [esi + mtrr_range.start] |
348 | mov ebp, dword [esi + mtrr_range.start+4] |
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349 | add ebx, dword [esi + mtrr_range.length] |
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350 | adc ebp, dword [esi + mtrr_range.length+4] |
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351 | mov edx, [esi + mtrr_range.next] |
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4608 | clevermous | 352 | mov eax, [.first_free_range] |
9715 | Doczom | 353 | mov [esi + mtrr_range.next], eax |
4608 | clevermous | 354 | mov [.first_free_range], esi |
355 | mov esi, edx |
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356 | .expand_wb_done: |
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357 | ; 5g. We have found the next range (maybe 0) after merging and |
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358 | ; the new end of range (maybe ebp:ebx from the new range |
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359 | ; or end of another existing interval calculated at step 5f). |
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360 | ; Write them to range at edi. |
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9715 | Doczom | 361 | mov [edi + mtrr_range.next], esi |
362 | sub ebx, dword [edi + mtrr_range.start] |
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363 | sbb ebp, dword [edi + mtrr_range.start+4] |
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364 | mov dword [edi + mtrr_range.length], ebx |
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365 | mov dword [edi + mtrr_range.length+4], ebp |
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4608 | clevermous | 366 | .next_wb_range: |
367 | ; 5h. Continue the loop 5b-5g over all configured MTRRs. |
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368 | add ecx, 16 |
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369 | cmp ecx, [.mtrrs_end] |
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370 | jb .fill_wb_ranges |
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371 | ; 6. Exclude all ranges marked as UC. |
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372 | ; 6a. Prepare for the loop over configured MTRRs filled at step 4. |
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373 | lea ecx, [.mtrrs] |
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374 | .fill_uc_ranges: |
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375 | ; 6b. Ignore non-UC MTRRs. |
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376 | mov ebx, [ecx] |
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377 | cmp bl, MEM_UC |
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378 | jnz .next_uc_range |
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379 | mov ebp, [ecx+4] |
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380 | and ebx, not 0xFFF ; clear memory type and reserved bits |
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381 | ; ebp:ebx = start of the range described by the current MTRR. |
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382 | lea esi, [.first_range] |
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383 | ; 6c. Find the first existing range containing a point greater than ebp:ebx. |
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384 | .find_range_uc: |
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385 | ; If there is no next range, ignore this MTRR, |
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386 | ; exit the loop and continue to next MTRR. |
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387 | mov edi, [esi] |
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388 | test edi, edi |
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389 | jz .next_uc_range |
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390 | ; If start of the next range is greater than or equal to ebp:ebx, |
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391 | ; exit the loop to 6e. |
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9715 | Doczom | 392 | mov eax, dword [edi + mtrr_range.start] |
393 | mov edx, dword [edi + mtrr_range.start+4] |
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4608 | clevermous | 394 | sub eax, ebx |
395 | sbb edx, ebp |
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396 | jnb .truncate_uc |
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397 | ; Otherwise, continue the loop if end of the next range is less than ebp:ebx, |
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398 | ; exit the loop to 6d otherwise. |
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399 | mov esi, edi |
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9715 | Doczom | 400 | add eax, dword [edi + mtrr_range.length] |
401 | adc edx, dword [edi + mtrr_range.length+4] |
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4608 | clevermous | 402 | jnb .find_range_uc |
403 | ; 6d. ebp:ebx is inside (or at end of) an existing range. |
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404 | ; Split the range. (The second range, maybe containing completely within UC-range, |
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405 | ; maybe of zero length, can be removed at step 6e, if needed.) |
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406 | mov edi, [.first_free_range] |
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407 | test edi, edi |
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408 | jz .abort |
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9715 | Doczom | 409 | mov dword [edi + mtrr_range.start], ebx |
410 | mov dword [edi + mtrr_range.start+4], ebp |
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411 | mov dword [edi + mtrr_range.length], eax |
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412 | mov dword [edi + mtrr_range.length+4], edx |
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413 | mov eax, [edi + mtrr_range.next] |
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4608 | clevermous | 414 | mov [.first_free_range], eax |
9715 | Doczom | 415 | mov eax, [esi + mtrr_range.next] |
416 | mov [edi + mtrr_range.next], eax |
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4608 | clevermous | 417 | ; don't change [esi+mtrr_range.next] yet, it will be filled at step 6e |
418 | mov eax, ebx |
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419 | mov edx, ebp |
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9715 | Doczom | 420 | sub eax, dword [esi + mtrr_range.start] |
421 | sbb edx, dword [esi + mtrr_range.start+4] |
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422 | mov dword [esi + mtrr_range.length], eax |
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423 | mov dword [esi + mtrr_range.length+4], edx |
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4608 | clevermous | 424 | .truncate_uc: |
425 | ; 6e. edi is the first range after ebp:ebx, check it and next ranges |
||
426 | ; for intersection with the new range, truncate heads. |
||
427 | add ebx, [ecx+8] |
||
428 | adc ebp, [ecx+12] |
||
429 | ; ebp:ebx = end of the range described by the current MTRR. |
||
430 | .truncate_uc_loop: |
||
431 | ; If start of the next range is greater than ebp:ebx, |
||
432 | ; exit the loop to 6g. |
||
433 | mov eax, ebx |
||
434 | mov edx, ebp |
||
9715 | Doczom | 435 | sub eax, dword [edi + mtrr_range.start] |
436 | sbb edx, dword [edi + mtrr_range.start+4] |
||
4608 | clevermous | 437 | jb .truncate_uc_done |
438 | ; Otherwise, if end of the next range is greater than ebp:ebx, |
||
439 | ; exit the loop to 6f. |
||
9715 | Doczom | 440 | sub eax, dword [edi + mtrr_range.length] |
441 | sbb edx, dword [edi + mtrr_range.length+4] |
||
4608 | clevermous | 442 | jb .truncate_uc_last |
443 | ; Otherwise, the current range is completely within the new range. |
||
444 | ; Free it and continue the loop if there is a next range. |
||
445 | ; If that was a last range, exit the loop to 6g. |
||
9715 | Doczom | 446 | mov edx, [edi + mtrr_range.next] |
4608 | clevermous | 447 | mov eax, [.first_free_range] |
448 | mov [.first_free_range], edi |
||
9715 | Doczom | 449 | mov [edi + mtrr_range.next], eax |
4608 | clevermous | 450 | mov edi, edx |
451 | test edi, edi |
||
452 | jnz .truncate_uc_loop |
||
453 | jmp .truncate_uc_done |
||
454 | .truncate_uc_last: |
||
455 | ; 6f. The range at edi partially intersects with the UC-range described by MTRR. |
||
456 | ; Truncate it from the head. |
||
9715 | Doczom | 457 | mov dword [edi + mtrr_range.start], ebx |
458 | mov dword [edi + mtrr_range.start+4], ebp |
||
4608 | clevermous | 459 | neg eax |
460 | adc edx, 0 |
||
461 | neg edx |
||
9715 | Doczom | 462 | mov dword [edi + mtrr_range.length], eax |
463 | mov dword [edi + mtrr_range.length+4], edx |
||
4608 | clevermous | 464 | .truncate_uc_done: |
465 | ; 6g. We have found the next range (maybe 0) after intersection. |
||
466 | ; Write it to [esi+mtrr_range.next]. |
||
9715 | Doczom | 467 | mov [esi + mtrr_range.next], edi |
4608 | clevermous | 468 | .next_uc_range: |
469 | ; 6h. Continue the loop 6b-6g over all configured MTRRs. |
||
470 | add ecx, 16 |
||
471 | cmp ecx, [.mtrrs_end] |
||
472 | jb .fill_uc_ranges |
||
473 | ; Sanity check: if there are no ranges after steps 5-6, |
||
474 | ; fallback to step 7. Otherwise, go to 8. |
||
475 | cmp [.first_range], 0 |
||
476 | jnz .ranges_ok |
||
477 | .fill_ranges_from_memory_map: |
||
478 | ; 7. BIOS has not configured variable-range MTRRs. |
||
479 | ; Create one range from 0 to [MEM_AMOUNT]. |
||
480 | mov eax, [.first_free_range] |
||
9715 | Doczom | 481 | mov edx, [eax + mtrr_range.next] |
4608 | clevermous | 482 | mov [.first_free_range], edx |
483 | mov [.first_range], eax |
||
484 | xor edx, edx |
||
9715 | Doczom | 485 | mov [eax + mtrr_range.next], edx |
486 | mov dword [eax + mtrr_range.start], edx |
||
487 | mov dword [eax + mtrr_range.start+4], edx |
||
4608 | clevermous | 488 | mov ecx, [MEM_AMOUNT] |
9715 | Doczom | 489 | mov dword [eax + mtrr_range.length], ecx |
490 | mov dword [eax + mtrr_range.length+4], edx |
||
4608 | clevermous | 491 | .ranges_ok: |
492 | ; 8. We have calculated list of WB-ranges. |
||
493 | ; Now we should calculate a list of MTRRs so that |
||
494 | ; * every MTRR describes a range with length = power of 2 and start that is aligned, |
||
495 | ; * every MTRR can be WB or UC |
||
496 | ; * (sum of all WB ranges) minus (sum of all UC ranges) equals the calculated list |
||
497 | ; * top of 4G memory must not be covered by any ranges |
||
498 | ; Example: range [0,0xBC000000) can be converted to |
||
499 | ; [0,0x80000000)+[0x80000000,0xC0000000)-[0xBC000000,0xC0000000) |
||
500 | ; WB +WB -UC |
||
501 | ; but not to [0,0x100000000)-[0xC0000000,0x100000000)-[0xBC000000,0xC0000000). |
||
502 | ; 8a. Check that list of ranges is [0,something) plus, optionally, [4G,something). |
||
503 | ; This holds in practice (see mtrrtest.asm for real-life examples) |
||
504 | ; and significantly simplifies the code: ranges are independent, start of range |
||
505 | ; is almost always aligned (the only exception >4G upper memory can be easily covered), |
||
506 | ; there is no need to consider adding holes before start of range, only |
||
507 | ; append them to end of range. |
||
2288 | clevermous | 508 | xor eax, eax |
4608 | clevermous | 509 | mov edi, [.first_range] |
9715 | Doczom | 510 | cmp dword [edi + mtrr_range.start], eax |
4608 | clevermous | 511 | jnz .abort |
9715 | Doczom | 512 | cmp dword [edi + mtrr_range.start+4], eax |
4608 | clevermous | 513 | jnz .abort |
9715 | Doczom | 514 | cmp dword [edi + mtrr_range.length+4], eax |
4608 | clevermous | 515 | jnz .abort |
9715 | Doczom | 516 | mov edx, [edi + mtrr_range.next] |
4608 | clevermous | 517 | test edx, edx |
518 | jz @f |
||
9715 | Doczom | 519 | cmp dword [edx + mtrr_range.start], eax |
4608 | clevermous | 520 | jnz .abort |
9715 | Doczom | 521 | cmp dword [edx + mtrr_range.start+4], 1 |
4608 | clevermous | 522 | jnz .abort |
9715 | Doczom | 523 | cmp [edx + mtrr_range.next], eax |
4608 | clevermous | 524 | jnz .abort |
3166 | clevermous | 525 | @@: |
4608 | clevermous | 526 | ; 8b. Initialize: no MTRRs filled. |
527 | mov [.num_used_mtrrs], eax |
||
528 | lea esi, [.mtrrs] |
||
529 | .range2mtrr_loop: |
||
530 | ; 8c. If we are dealing with upper-memory range (after 4G) |
||
531 | ; with length > start, create one WB MTRR with [start,2*start), |
||
532 | ; reset start to 2*start and return to this step. |
||
533 | ; Example: [4G,24G) -> [4G,8G) {returning} + [8G,16G) {returning} |
||
534 | ; + [16G,24G) {advancing to ?}. |
||
9715 | Doczom | 535 | mov eax, dword [edi + mtrr_range.length+4] |
2288 | clevermous | 536 | test eax, eax |
4608 | clevermous | 537 | jz .less4G |
9715 | Doczom | 538 | mov edx, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 539 | cmp eax, edx |
540 | jb .start_aligned |
||
541 | inc [.num_used_mtrrs] |
||
542 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
543 | ja .abort |
||
544 | mov dword [esi], MEM_WB |
||
545 | mov dword [esi+4], edx |
||
546 | mov dword [esi+8], 0 |
||
547 | mov dword [esi+12], edx |
||
548 | add esi, 16 |
||
9715 | Doczom | 549 | add dword [edi + mtrr_range.start+4], edx |
550 | sub dword [edi + mtrr_range.length+4], edx |
||
4608 | clevermous | 551 | jnz .range2mtrr_loop |
9715 | Doczom | 552 | cmp dword [edi + mtrr_range.length], 0 |
4608 | clevermous | 553 | jz .range2mtrr_next |
554 | .less4G: |
||
555 | ; 8d. If we are dealing with low-memory range (before 4G) |
||
556 | ; and appending a maximal-size hole would create a range covering top of 4G, |
||
557 | ; create a maximal-size WB range and return to this step. |
||
558 | ; Example: for [0,0xBC000000) the following steps would consider |
||
559 | ; variants [0,0x80000000)+(another range to be splitted) and |
||
560 | ; [0,0x100000000)-(another range to be splitted); we forbid the last variant, |
||
561 | ; so the first variant must be used. |
||
9715 | Doczom | 562 | bsr ecx, dword [edi + mtrr_range.length] |
4608 | clevermous | 563 | xor edx, edx |
564 | inc edx |
||
565 | shl edx, cl |
||
566 | lea eax, [edx*2] |
||
9715 | Doczom | 567 | add eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 568 | jnz .start_aligned |
569 | inc [.num_used_mtrrs] |
||
570 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
571 | ja .abort |
||
9715 | Doczom | 572 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 573 | mov dword [esi], eax |
574 | or dword [esi], MEM_WB |
||
575 | mov dword [esi+4], 0 |
||
576 | mov dword [esi+8], edx |
||
577 | mov dword [esi+12], 0 |
||
578 | add esi, 16 |
||
9715 | Doczom | 579 | add dword [edi + mtrr_range.start], edx |
580 | sub dword [edi + mtrr_range.length], edx |
||
4608 | clevermous | 581 | jnz .less4G |
582 | jmp .range2mtrr_next |
||
583 | .start_aligned: |
||
584 | ; Start is aligned for any allowed length, maximum-size hole is allowed. |
||
585 | ; Select the best MTRR configuration for one range. |
||
586 | ; length=...101101 |
||
587 | ; Without hole at the end, we need one WB MTRR for every 1-bit in length: |
||
588 | ; length=...100000 + ...001000 + ...000100 + ...000001 |
||
589 | ; We can also append one hole at the end so that one 0-bit (selected by us) |
||
590 | ; becomes 1 and all lower bits become 0 for WB-range: |
||
591 | ; length=...110000 - (...00010 + ...00001) |
||
592 | ; In this way, we need one WB MTRR for every 1-bit higher than the selected bit, |
||
593 | ; one WB MTRR for the selected bit, one UC MTRR for every 0-bit between |
||
594 | ; the selected bit and lowest 1-bit (they become 1-bits after negation) |
||
595 | ; and one UC MTRR for lowest 1-bit. |
||
596 | ; So we need to select 0-bit with the maximal difference |
||
597 | ; (number of 0-bits) - (number of 1-bits) between selected and lowest 1-bit, |
||
598 | ; this equals the gain from using a hole. If the difference is negative for |
||
599 | ; all 0-bits, don't append hole. |
||
600 | ; Note that lowest 1-bit is not included when counting, but selected 0-bit is. |
||
601 | ; 8e. Find the optimal bit position for hole. |
||
602 | ; eax = current difference, ebx = best difference, |
||
603 | ; ecx = hole bit position, edx = current bit position. |
||
2288 | clevermous | 604 | xor eax, eax |
4608 | clevermous | 605 | xor ebx, ebx |
606 | xor ecx, ecx |
||
9715 | Doczom | 607 | bsf edx, dword [edi + mtrr_range.length] |
4608 | clevermous | 608 | jnz @f |
9715 | Doczom | 609 | bsf edx, dword [edi + mtrr_range.length+4] |
4608 | clevermous | 610 | add edx, 32 |
2288 | clevermous | 611 | @@: |
4608 | clevermous | 612 | push edx ; save position of lowest 1-bit for step 8f |
613 | .calc_stat: |
||
2288 | clevermous | 614 | inc edx |
4608 | clevermous | 615 | cmp edx, 64 |
616 | jae .stat_done |
||
617 | inc eax ; increment difference in hope for 1-bit |
||
618 | ; Note: bt conveniently works with both .length and .length+4, |
||
619 | ; depending on whether edx>=32. |
||
9715 | Doczom | 620 | bt dword [edi + mtrr_range.length], edx |
4608 | clevermous | 621 | jc .calc_stat |
622 | dec eax ; hope was wrong, decrement difference to correct 'inc' |
||
623 | dec eax ; and again, now getting the real difference |
||
624 | cmp eax, ebx |
||
625 | jle .calc_stat |
||
626 | mov ebx, eax |
||
627 | mov ecx, edx |
||
628 | jmp .calc_stat |
||
629 | .stat_done: |
||
630 | ; 8f. If we decided to create a hole, flip all bits between lowest and selected. |
||
631 | pop edx ; restore position of lowest 1-bit saved at step 8e |
||
632 | test ecx, ecx |
||
633 | jz .fill_hi_init |
||
2288 | clevermous | 634 | @@: |
635 | inc edx |
||
4608 | clevermous | 636 | cmp edx, ecx |
637 | ja .fill_hi_init |
||
9715 | Doczom | 638 | btc dword [edi + mtrr_range.length], edx |
4608 | clevermous | 639 | jmp @b |
640 | .fill_hi_init: |
||
641 | ; 8g. Create MTRR ranges corresponding to upper 32 bits. |
||
642 | sub ecx, 32 |
||
643 | .fill_hi_loop: |
||
9715 | Doczom | 644 | bsr edx, dword [edi + mtrr_range.length+4] |
4608 | clevermous | 645 | jz .fill_hi_done |
646 | inc [.num_used_mtrrs] |
||
647 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
648 | ja .abort |
||
9715 | Doczom | 649 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 650 | mov [esi], eax |
9715 | Doczom | 651 | mov eax, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 652 | mov [esi+4], eax |
653 | xor eax, eax |
||
654 | mov [esi+8], eax |
||
655 | bts eax, edx |
||
656 | mov [esi+12], eax |
||
657 | cmp edx, ecx |
||
658 | jl .fill_hi_uc |
||
659 | or dword [esi], MEM_WB |
||
9715 | Doczom | 660 | add dword [edi + mtrr_range.start+4], eax |
4608 | clevermous | 661 | jmp @f |
662 | .fill_hi_uc: |
||
663 | sub dword [esi+4], eax |
||
9715 | Doczom | 664 | sub dword [edi + mtrr_range.start+4], eax |
2288 | clevermous | 665 | @@: |
4608 | clevermous | 666 | add esi, 16 |
9715 | Doczom | 667 | sub dword [edi + mtrr_range.length], eax |
4608 | clevermous | 668 | jmp .fill_hi_loop |
669 | .fill_hi_done: |
||
670 | ; 8h. Create MTRR ranges corresponding to lower 32 bits. |
||
671 | add ecx, 32 |
||
672 | .fill_lo_loop: |
||
673 | bsr edx, dword [edi+mtrr_range.length] |
||
674 | jz .range2mtrr_next |
||
675 | inc [.num_used_mtrrs] |
||
676 | cmp [.num_used_mtrrs], MAX_USEFUL_MTRRS |
||
677 | ja .abort |
||
9715 | Doczom | 678 | mov eax, dword [edi + mtrr_range.start] |
4608 | clevermous | 679 | mov [esi], eax |
9715 | Doczom | 680 | mov eax, dword [edi + mtrr_range.start+4] |
4608 | clevermous | 681 | mov [esi+4], eax |
682 | xor eax, eax |
||
683 | mov [esi+12], eax |
||
684 | bts eax, edx |
||
685 | mov [esi+8], eax |
||
686 | cmp edx, ecx |
||
687 | jl .fill_lo_uc |
||
688 | or dword [esi], MEM_WB |
||
9715 | Doczom | 689 | add dword [edi + mtrr_range.start], eax |
4608 | clevermous | 690 | jmp @f |
691 | .fill_lo_uc: |
||
692 | sub dword [esi], eax |
||
9715 | Doczom | 693 | sub dword [edi + mtrr_range.start], eax |
2288 | clevermous | 694 | @@: |
4608 | clevermous | 695 | add esi, 16 |
9715 | Doczom | 696 | sub dword [edi + mtrr_range.length], eax |
4608 | clevermous | 697 | jmp .fill_lo_loop |
698 | .range2mtrr_next: |
||
699 | ; 8i. Repeat the loop at 8c-8h for all ranges. |
||
9715 | Doczom | 700 | mov edi, [edi + mtrr_range.next] |
2288 | clevermous | 701 | test edi, edi |
4608 | clevermous | 702 | jnz .range2mtrr_loop |
703 | ; 9. We have calculated needed MTRRs, now setup them in the CPU. |
||
704 | ; 9a. Abort if number of MTRRs is too large. |
||
705 | mov eax, [num_variable_mtrrs] |
||
706 | cmp [.num_used_mtrrs], eax |
||
707 | ja .abort |
||
2288 | clevermous | 708 | |
4608 | clevermous | 709 | ; 9b. Prepare for changes. |
710 | call mtrr_begin_change |
||
2288 | clevermous | 711 | |
4608 | clevermous | 712 | ; 9c. Prepare for loop over MTRRs. |
713 | lea esi, [.mtrrs] |
||
714 | mov ecx, 0x200 |
||
2288 | clevermous | 715 | @@: |
4608 | clevermous | 716 | ; 9d. For every MTRR, copy PHYSBASEn as is: step 8 has configured |
717 | ; start value and type bits as needed. |
||
718 | mov eax, [esi] |
||
719 | mov edx, [esi+4] |
||
720 | wrmsr |
||
721 | inc ecx |
||
722 | ; 9e. For every MTRR, calculate PHYSMASKn = -(length) or 0x800 |
||
723 | ; with upper bits cleared, 0x800 = MTRR is valid. |
||
2288 | clevermous | 724 | xor eax, eax |
725 | xor edx, edx |
||
4608 | clevermous | 726 | sub eax, [esi+8] |
727 | sbb edx, [esi+12] |
||
728 | or eax, 0x800 |
||
729 | or edx, [.phys_reserved_mask] |
||
730 | xor edx, [.phys_reserved_mask] |
||
2288 | clevermous | 731 | wrmsr |
732 | inc ecx |
||
4608 | clevermous | 733 | ; 9f. Continue steps 9d and 9e for all MTRRs calculated at step 8. |
734 | add esi, 16 |
||
735 | dec [.num_used_mtrrs] |
||
736 | jnz @b |
||
737 | ; 9g. Zero other MTRRs. |
||
2288 | clevermous | 738 | xor eax, eax |
739 | xor edx, edx |
||
4608 | clevermous | 740 | mov ebx, [num_variable_mtrrs] |
741 | lea ebx, [0x200+ebx*2] |
||
2288 | clevermous | 742 | @@: |
4608 | clevermous | 743 | cmp ecx, ebx |
744 | jae @f |
||
745 | wrmsr |
||
4418 | clevermous | 746 | inc ecx |
2288 | clevermous | 747 | wrmsr |
4608 | clevermous | 748 | inc ecx |
749 | jmp @b |
||
750 | @@: |
||
751 | |||
9950 | turbocat | 752 | ; 9i. Changes are done. |
4608 | clevermous | 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 |