diff options
Diffstat (limited to 'tools/firmware/rombios/rombios.c')
| -rw-r--r-- | tools/firmware/rombios/rombios.c | 61 |
1 files changed, 35 insertions, 26 deletions
diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c index 1aeb7f664f..51370a9c54 100644 --- a/tools/firmware/rombios/rombios.c +++ b/tools/firmware/rombios/rombios.c @@ -181,8 +181,15 @@ // EBDA is used for PS/2 mouse support, and IDE BIOS, etc. #define EBDA_SEG 0x9FC0 #define EBDA_SIZE 1 // In KiB +#define EBDA_SEG_PTR 0x40E /* Find true EBDA segment at 0:40E */ #define BASE_MEM_IN_K (640 - EBDA_SIZE) +/* 256 bytes at 0x9ff00 -- 0x9ffff is used for the IPL boot table. */ +#define IPL_TABLE_OFFSET 0x0300 /* offset from EBDA */ +#define IPL_TABLE_ENTRIES 8 +#define IPL_COUNT_OFFSET 0x0380 /* u16: number of valid table entries */ +#define IPL_SEQUENCE_OFFSET 0x0382 /* u16: next boot device */ + // Define the application NAME #ifdef HVMASSIST # define BX_APPNAME "HVMAssist" @@ -1963,13 +1970,6 @@ print_bios_banner() // http://www.phoenix.com/en/Customer+Services/White+Papers-Specs/pc+industry+specifications.htm //-------------------------------------------------------------------------- -/* 256 bytes at 0x9ff00 -- 0x9ffff is used for the IPL boot table. */ -#define IPL_SEG 0x9ff0 -#define IPL_TABLE_OFFSET 0x0000 -#define IPL_TABLE_ENTRIES 8 -#define IPL_COUNT_OFFSET 0x0080 /* u16: number of valid table entries */ -#define IPL_SEQUENCE_OFFSET 0x0082 /* u16: next boot device */ - struct ipl_entry { Bit16u type; Bit16u flags; @@ -1986,29 +1986,29 @@ init_boot_vectors() Bit16u ss = get_SS(); /* Clear out the IPL table. */ - memsetb(IPL_SEG, IPL_TABLE_OFFSET, 0, 0xff); + memsetb(EBDA_SEG, IPL_TABLE_OFFSET, 0, 0xff); /* Floppy drive */ e.type = 1; e.flags = 0; e.vector = 0; e.description = 0; e.reserved = 0; - memcpyb(IPL_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); + memcpyb(EBDA_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); count++; /* First HDD */ e.type = 2; e.flags = 0; e.vector = 0; e.description = 0; e.reserved = 0; - memcpyb(IPL_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); + memcpyb(EBDA_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); count++; #if BX_ELTORITO_BOOT /* CDROM */ e.type = 3; e.flags = 0; e.vector = 0; e.description = 0; e.reserved = 0; - memcpyb(IPL_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); + memcpyb(EBDA_SEG, IPL_TABLE_OFFSET + count * sizeof (e), ss, &e, sizeof (e)); count++; #endif /* Remember how many devices we have */ - write_word(IPL_SEG, IPL_COUNT_OFFSET, count); + write_word(EBDA_SEG, IPL_COUNT_OFFSET, count); /* Not tried booting anything yet */ - write_word(IPL_SEG, IPL_SEQUENCE_OFFSET, 0xffff); + write_word(EBDA_SEG, IPL_SEQUENCE_OFFSET, 0xffff); } static Bit8u @@ -2017,11 +2017,12 @@ Bit16u i; struct ipl_entry *e; { Bit16u count; Bit16u ss = get_SS(); + Bit16u ebda_seg = read_word(0x0040, 0x000E); /* Get the count of boot devices, and refuse to overrun the array */ - count = read_word(IPL_SEG, IPL_COUNT_OFFSET); + count = read_word(ebda_seg, IPL_COUNT_OFFSET); if (i >= count) return 0; /* OK to read this device */ - memcpyb(ss, e, IPL_SEG, IPL_TABLE_OFFSET + i * sizeof (*e), sizeof (*e)); + memcpyb(ss, e, ebda_seg, IPL_TABLE_OFFSET + i * sizeof (*e), sizeof (*e)); return 1; } @@ -2187,9 +2188,10 @@ int bootmenu(selected) { Bit8u scode; int max; + Bit16u ebda_seg = read_word(0x0040, 0x000E); /* get the number of boot devices */ - max = read_word(IPL_SEG, IPL_COUNT_OFFSET); + max = read_word(ebda_seg, IPL_COUNT_OFFSET); for(;;) { if (selected > max || selected < 1) selected = 1; @@ -2349,7 +2351,9 @@ s3_resume() ASM_START push ds push ax - mov ax, #EBDA_SEG + xor ax, ax + mov ds, ax + mov ax, word ptr [EBDA_SEG_PTR] mov ds, ax mov al, [EBDA_CMOS_SHUTDOWN_STATUS_OFFSET] mov .s3_resume.cmos_shutdown_status[bp], al @@ -8543,7 +8547,8 @@ int18_handler: ;; Boot Failure recovery: try the next device. ;; Get the boot sequence number out of the IPL memory ;; The first time we do this it will have been set to -1 so ;; we will start from device 0. - mov bx, #IPL_SEG + mov ds, ax + mov bx, word ptr [EBDA_SEG_PTR] mov ds, bx ;; Set segment mov bx, IPL_SEQUENCE_OFFSET ;; BX is now the sequence number inc bx ;; ++ @@ -8686,8 +8691,8 @@ hard_drive_post: SET_INT_VECTOR(0x76, #0xF000, #int76_handler) ;; INT 41h: hard disk 0 configuration pointer ;; INT 46h: hard disk 1 configuration pointer - SET_INT_VECTOR(0x41, #EBDA_SEG, #0x003D) - SET_INT_VECTOR(0x46, #EBDA_SEG, #0x004D) + SET_INT_VECTOR(0x41, word ptr [EBDA_SEG_PTR], #0x003D) + SET_INT_VECTOR(0x46, word ptr [EBDA_SEG_PTR], #0x004D) ;; move disk geometry data from CMOS to EBDA disk parameter table(s) mov al, #0x12 @@ -8716,7 +8721,9 @@ post_d0_type47: ;; 22 landing zone high D ;; 23 sectors/track E - mov ax, #EBDA_SEG + xor ax, ax + mov ds, ax + mov ax, word ptr [EBDA_SEG_PTR] mov ds, ax ;;; Filling EBDA table for hard disk 0. @@ -8985,7 +8992,7 @@ ebda_post: #endif xor ax, ax ; mov EBDA seg into 40E mov ds, ax - mov word ptr [0x40E], #EBDA_SEG + mov word ptr [EBDA_SEG_PTR], #EBDA_SEG ret;; ;-------------------- @@ -9754,15 +9761,17 @@ no_bcv: je no_bev ;; Found a device that thinks it can boot the system. Record its BEV. - mov bx, #IPL_SEG ;; Go to the segment where the IPL table lives + xor bx, bx mov ds, bx + mov bx, word ptr [EBDA_SEG_PTR] + mov ds, bx ;; Go to the segment where the IPL table lives mov bx, IPL_COUNT_OFFSET ;; Read the number of entries so far cmp bx, #IPL_TABLE_ENTRIES je no_bev ;; Get out if the table is full shl bx, #0x4 ;; Turn count into offset (entries are 16 bytes) - mov 0[bx], #0x80 ;; This entry is a BEV device - mov 6[bx], cx ;; Build a far pointer from the segment... - mov 4[bx], ax ;; and the offset + mov IPL_TABLE_OFFSET+0[bx], #0x80 ;; This entry is a BEV device + mov IPL_TABLE_OFFSET+6[bx], cx ;; Build a far pointer from the segment... + mov IPL_TABLE_OFFSET+4[bx], ax ;; and the offset shr bx, #0x4 ;; Turn the offset back into a count inc bx ;; We have one more entry now mov IPL_COUNT_OFFSET, bx ;; Remember that. |