| 1360,113 → 1360,6 |
|---|
| endp |
| |
| align 4 |
| proc init_mtrr |
| |
| cmp [BOOT_VARS+BOOT_MTRR], byte 2 |
| je .exit |
| |
| bt [cpu_caps], CAPS_MTRR |
| jnc .exit |
| |
| mov eax, cr0 |
| or eax, 0x60000000 ;disable caching |
| mov cr0, eax |
| wbinvd ;invalidate cache |
| |
| mov ecx, 0x2FF |
| rdmsr ; |
| ; has BIOS already initialized MTRRs? |
| test ah, 8 |
| jnz .skip_init |
| ; rarely needed, so mainly placeholder |
| ; main memory - cached |
| push eax |
| |
| mov eax, [MEM_AMOUNT] |
| ; round eax up to next power of 2 |
| dec eax |
| bsr ecx, eax |
| mov ebx, 2 |
| shl ebx, cl |
| dec ebx |
| ; base of memory range = 0, type of memory range = MEM_WB |
| xor edx, edx |
| mov eax, MEM_WB |
| mov ecx, 0x200 |
| wrmsr |
| ; mask of memory range = 0xFFFFFFFFF - (size - 1), ebx = size - 1 |
| mov eax, 0xFFFFFFFF |
| mov edx, 0x0000000F |
| sub eax, ebx |
| sbb edx, 0 |
| or eax, 0x800 |
| inc ecx |
| wrmsr |
| ; clear unused MTRRs |
| xor eax, eax |
| xor edx, edx |
| @@: |
| inc ecx |
| wrmsr |
| cmp ecx, 0x20F |
| jb @b |
| ; enable MTRRs |
| pop eax |
| or ah, 8 |
| and al, 0xF0; default memtype = UC |
| mov ecx, 0x2FF |
| wrmsr |
| .skip_init: |
| stdcall set_mtrr, [LFBAddress], [LFBSize], MEM_WC |
| |
| wbinvd ;again invalidate |
| |
| mov eax, cr0 |
| and eax, not 0x60000000 |
| mov cr0, eax ; enable caching |
| .exit: |
| ret |
| endp |
| |
| align 4 |
| proc set_mtrr stdcall, base:dword,size:dword,mem_type:dword |
| ; find unused register |
| mov ecx, 0x201 |
| @@: |
| rdmsr |
| dec ecx |
| test ah, 8 |
| jz .found |
| rdmsr |
| mov al, 0; clear memory type field |
| cmp eax, [base] |
| jz .ret |
| add ecx, 3 |
| cmp ecx, 0x210 |
| jb @b |
| ; no free registers, ignore the call |
| .ret: |
| ret |
| .found: |
| ; found, write values |
| xor edx, edx |
| mov eax, [base] |
| or eax, [mem_type] |
| wrmsr |
| |
| mov ebx, [size] |
| dec ebx |
| mov eax, 0xFFFFFFFF |
| mov edx, 0x00000000 |
| sub eax, ebx |
| sbb edx, 0 |
| or eax, 0x800 |
| inc ecx |
| wrmsr |
| ret |
| endp |
| |
| align 4 |
| proc create_ring_buffer stdcall, size:dword, flags:dword |
| locals |
| buf_ptr dd ? |