1 | ; Project name : XTIDE Universal BIOS |
---|
2 | ; Description : Functions for loading correct transfer command. |
---|
3 | |
---|
4 | ; Section containing code |
---|
5 | SECTION .text |
---|
6 | |
---|
7 | ;-------------------------------------------------------------------- |
---|
8 | ; CommandLookup_GetEbiosIndexToBX |
---|
9 | ; CommandLookup_OrOldInt13hIndexToBL |
---|
10 | ; Parameters: |
---|
11 | ; DS:DI: Ptr to DPT |
---|
12 | ; ES:SI: Ptr to DAP (Disk Address Packet) |
---|
13 | ; Returns: |
---|
14 | ; BX: Index to command lookup table |
---|
15 | ; Corrupts registers: |
---|
16 | ; AX |
---|
17 | ;-------------------------------------------------------------------- |
---|
18 | ALIGN JUMP_ALIGN |
---|
19 | CommandLookup_GetEbiosIndexToBX: |
---|
20 | ; LBA28 or LBA48 command |
---|
21 | xor bx, bx |
---|
22 | mov ax, [es:si+DAP.qwLBA+3] ; Load LBA48 bytes 3 and 4 |
---|
23 | and al, ~0Fh ; Clear LBA28 bits 24...27 |
---|
24 | or al, [es:si+DAP.qwLBA+5] |
---|
25 | cmp bx, ax ; Set CF if any of bits 28...47 set |
---|
26 | rcl bx, 1 ; BX = 0 for LBA28, BX = 1 for LBA48 |
---|
27 | |
---|
28 | ; Block mode or single sector |
---|
29 | ALIGN JUMP_ALIGN |
---|
30 | CommandLookup_OrOldInt13hIndexToBL: |
---|
31 | mov al, FLGH_DPT_BLOCK_MODE_SUPPORTED ; Bit 1 |
---|
32 | and al, [di+DPT.bFlagsHigh] |
---|
33 | or bl, al ; BX = index to lookup table |
---|
34 | ret |
---|
35 | |
---|
36 | |
---|
37 | g_rgbReadCommandLookup: |
---|
38 | db COMMAND_READ_SECTORS ; 00b, CHS or LBA28 single sector |
---|
39 | db COMMAND_READ_SECTORS_EXT ; 01b, LBA48 single sector |
---|
40 | db COMMAND_READ_MULTIPLE ; 10b, CHS or LBA28 block mode |
---|
41 | db COMMAND_READ_MULTIPLE_EXT ; 11b, LBA48 block mode |
---|
42 | |
---|
43 | g_rgbWriteCommandLookup: |
---|
44 | db COMMAND_WRITE_SECTORS |
---|
45 | db COMMAND_WRITE_SECTORS_EXT |
---|
46 | db COMMAND_WRITE_MULTIPLE |
---|
47 | db COMMAND_WRITE_MULTIPLE_EXT |
---|
48 | |
---|
49 | g_rgbVerifyCommandLookup: |
---|
50 | db COMMAND_VERIFY_SECTORS |
---|
51 | db COMMAND_VERIFY_SECTORS_EXT |
---|
52 | db COMMAND_VERIFY_SECTORS |
---|
53 | db COMMAND_VERIFY_SECTORS_EXT |
---|
54 | |
---|