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- #if (TRY_FLOPPY_FIRST > 0)
-
- /*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2, or (at
- * your option) any later version.
- */
-
- #include "etherboot.h"
-
- #define BOOTSECT ((char *)0x7C00)
- #define BOOTSIG ((unsigned short *)BOOTSECT)[0xFF]
- #define PARTTAB ((partentry *)(BOOTSECT+0x1BE))
-
- typedef struct partentry {
- unsigned char flags;
- unsigned char start_head;
- unsigned char start_sector;
- unsigned char start_cylinder;
- unsigned char type;
- unsigned char end_head;
- unsigned char end_sector;
- unsigned char end_cylinder;
- unsigned long offset;
- unsigned long length;
- } partentry;
-
- static unsigned int disk_read_retry(int dev,int c,int h,int s)
- {
- int retry = 3,rc;
-
- while (retry-- && (rc = pcbios_disk_read(dev,c,h,s,BOOTSECT)) != 0);
- if (BOOTSIG != 0xAA55) {
- printf("not a boot sector");
- return(0xFFFF); }
- return(rc);
- }
-
- int bootdisk(int dev,int part)
- {
- int rc;
-
- disk_init();
- if ((rc = disk_read_retry(dev,0,0,1)) != 0) {
- readerr:
- if (rc != 0xFFFF)
- printf("read error (%#hhX)",rc/256);
- return(0); }
- if (part) {
- partentry *ptr;
-
- if (part >= 5) {
- int i;
- for (i = 0, ptr = PARTTAB; ptr->type != 5; ptr++)
- if (++i == 4) {
- printf("partition not found");
- return(0); }
- if ((rc = disk_read_retry(dev,
- ptr->start_cylinder,
- ptr->start_head,
- ptr->start_sector)) != 0)
- goto readerr;
- part -= 4; }
- if (!(ptr = PARTTAB-1+part)->type) {
- printf("empty partition");
- return(0); }
- if ((rc = disk_read_retry(dev,
- ptr->start_cylinder,
- ptr->start_head,
- ptr->start_sector)) != 0)
- goto readerr; }
- cleanup();
- gateA20_unset();
- /* Set %edx to device number to emulate BIOS
- Fortunately %edx is not used after this */
- __asm__("movl %0,%%edx" : : "g" (dev));
- xstart((unsigned long)BOOTSECT, 0, 0);
- return(0);
- }
-
- #endif
-
- /*
- * Local variables:
- * c-basic-offset: 8
- * End:
- */
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