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
39 /* make sure stack is at 0000: */
42 OPSIZE; ANDL $0xFFFF, SP
44 /* convert 16-bit return pc to far pointer */
49 SEGSS; LGDT(tgdtptr(SB))
51 /* enable protected mode */
57 FARJUMP16(EXEC16SEL, pmode32flush(SB));
58 TEXT pmode32flush(SB), $0
60 /* load 32-bit protected mode data selector */
64 /* load all data segments */
73 /* setup farret to rmode16x */
77 /* load 16-bit protected mode data selector */
82 /* disable protected mode */
88 FARJUMP16(0, rmode16flush(SB));
89 TEXT rmode16flush(SB), $0
92 * load 16-bit realmode data segment 0000: and
93 * return to 32 bit return pc interpreted
94 * as 16 bit far pointer.
100 /* null descriptor */
104 /* data segment descriptor for 4 gigabytes (PL 0) */
106 LONG $(SEGG|SEGB|(0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW)
108 /* exec segment descriptor for 4 gigabytes (PL 0) */
110 LONG $(SEGG|SEGD|(0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR)
112 /* data segment descriptor for (PL 0) 16-bit */
114 LONG $((0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW)
116 /* exec segment descriptor for (PL 0) 16-bit */
118 LONG $((0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR)
190 /* get pxe env structure in ES:BX */
195 /* !PXE or PXEENV+ signature */
196 SEGES; LXW(0, xBX, rAX)
197 CMPI((('!'<<0)|('P'<<8)), rAX)
199 CMPI((('P'<<0)|('X'<<8)), rAX)
202 SEGES; LXW(0x2A, xBX, rAX)
203 SEGES; LXW(0x28, xBX, rBX)
207 SEGES; LXW(0x12, xBX, rAX)
209 SEGES; LXW(0x10, xBX, rAX)
214 TEXT pxecallret(SB), $0
232 PUSHI(pxecallret(SB))
262 TEXT readsect16(SB), $0
266 PUSHR(rCX) /* qword lba */
271 PUSHR(rCX) /* dword buffer */
275 PUSHR(rCX) /* word # of sectors */
277 PUSHI(0x0010) /* byte reserved, byte packet size */
294 TEXT readsect(SB), $0
301 CALL16(readsect16(SB))
310 TEXT bootname(SB), $0
311 BYTE $'3'; BYTE $'8'; BYTE $'6'; BYTE $'/';
312 BYTE $'9'; BYTE $'b'; BYTE $'o'; BYTE $'o';
313 BYTE $'t'; BYTE $'i'; BYTE $'s'; BYTE $'o';
319 BYTE $'\r'; BYTE $'\n'; BYTE $0
322 BYTE $'0'; BYTE $'1'; BYTE $'2'; BYTE $'3';
323 BYTE $'4'; BYTE $'5'; BYTE $'6'; BYTE $'7';
324 BYTE $'8'; BYTE $'9'; BYTE $'a'; BYTE $'b';
325 BYTE $'c'; BYTE $'d'; BYTE $'e'; BYTE $'f'