6 #define DATA32SEL SELECTOR(1, SELGDT, 0)
7 #define EXEC32SEL SELECTOR(2, SELGDT, 0)
8 #define DATA16SEL SELECTOR(3, SELGDT, 0)
9 #define EXEC16SEL SELECTOR(4, SELGDT, 0)
11 #define SEGSS BYTE $0x36
12 #define SEGES BYTE $0x26
13 #define FARRET BYTE $0xCB
19 OPSIZE; MOVL $origin(SB), SP
21 OPSIZE; ADSIZE; PUSHL SP
22 OPSIZE; ADSIZE; PUSHL CX
31 /* make sure stack is at 0000: */
34 OPSIZE; ANDL $0xFFFF, SP
36 /* convert 16-bit return pc to far pointer */
41 SEGSS; LGDT(tgdtptr(SB))
43 /* enable protected mode */
49 FARJUMP16(EXEC16SEL, pmode32flush(SB));
50 TEXT pmode32flush(SB), $0
52 /* load 32-bit protected mode data selector */
56 /* load all data segments */
65 /* setup farret to rmode16x */
69 /* load 16-bit protected mode data selector */
74 /* disable protected mode */
80 FARJUMP16(0, rmode16flush(SB));
81 TEXT rmode16flush(SB), $0
84 * load 16-bit realmode data segment 0000: and
85 * return to 32 bit return pc interpreted
86 * as 16 bit far pointer.
96 /* data segment descriptor for 4 gigabytes (PL 0) */
98 LONG $(SEGG|SEGB|(0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW)
100 /* exec segment descriptor for 4 gigabytes (PL 0) */
102 LONG $(SEGG|SEGD|(0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR)
104 /* data segment descriptor for (PL 0) 16-bit */
106 LONG $((0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW)
108 /* exec segment descriptor for (PL 0) 16-bit */
110 LONG $((0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR)
164 /* get pxe env structure in ES:BX */
169 /* !PXE or PXEENV+ signature */
170 SEGES; LXW(0, xBX, rAX)
171 CMPI((('!'<<0)|('P'<<8)), rAX)
173 CMPI((('P'<<0)|('X'<<8)), rAX)
176 SEGES; LXW(0x2A, xBX, rAX)
177 SEGES; LXW(0x28, xBX, rBX)
181 SEGES; LXW(0x12, xBX, rAX)
183 SEGES; LXW(0x10, xBX, rAX)
188 TEXT pxecallret(SB), $0
206 PUSHI(pxecallret(SB))
236 TEXT readsect16(SB), $0
240 PUSHR(rCX) /* qword lba */
245 PUSHR(rCX) /* dword buffer */
249 PUSHR(rCX) /* word # of sectors */
251 PUSHI(0x0010) /* byte reserved, byte packet size */
268 TEXT readsect(SB), $0
275 CALL16(readsect16(SB))
284 TEXT bootname(SB), $0
285 BYTE $'3'; BYTE $'8'; BYTE $'6'; BYTE $'/';
286 BYTE $'9'; BYTE $'b'; BYTE $'o'; BYTE $'o';
287 BYTE $'t'; BYTE $'i'; BYTE $'s'; BYTE $'o';
296 BYTE $'0'; BYTE $'1'; BYTE $'2'; BYTE $'3';
297 BYTE $'4'; BYTE $'5'; BYTE $'6'; BYTE $'7';
298 BYTE $'8'; BYTE $'9'; BYTE $'a'; BYTE $'b';
299 BYTE $'c'; BYTE $'d'; BYTE $'e'; BYTE $'f'