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Boot environment option 'bios_remap_first'. Thios option remaps the first

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BIOS drive to d7, the second BIOS drive to d0, the third to d1, etc. This
useful for CD-ROM hardisk emulation.
This commit is contained in:
Philip Homburg 2005-08-15 13:19:02 +00:00
parent d807719b57
commit c392c177b5
1 changed files with 34 additions and 12 deletions
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46
drivers/bios_wini/bios_wini.c
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@ -36,7 +36,7 @@
#define ERR (-1) /* general error */
/* Parameters for the disk drive. */
#define MAX_DRIVES 4 /* this driver supports 4 drives (d0 - d3)*/
#define MAX_DRIVES 8 /* this driver supports 8 drives (d0 - d7)*/
#define MAX_SECS 255 /* bios can transfer this many sectors */
#define NR_MINORS (MAX_DRIVES * DEV_PER_DRIVE)
#define SUB_PER_DRIVE (NR_PARTITIONS * NR_PARTITIONS)
@ -50,16 +50,18 @@ PRIVATE struct wini { /* main drive struct, one entry per drive */
unsigned heads; /* number of heads */
unsigned sectors; /* number of sectors per track */
unsigned open_ct; /* in-use count */
int drive_id; /* Drive ID at BIOS level */
int present; /* Valid drive */
int int13ext; /* IBM/MS INT 13 extensions supported? */
struct device part[DEV_PER_DRIVE]; /* disks and partitions */
struct device subpart[SUB_PER_DRIVE]; /* subpartitions */
} wini[MAX_DRIVES], *w_wn;
PRIVATE int nr_drives = MAX_DRIVES; /* Number of drives */
PRIVATE int w_drive; /* selected drive */
PRIVATE struct device *w_dv; /* device's base and size */
PRIVATE vir_bytes bios_buf_vir, bios_buf_size;
PRIVATE phys_bytes bios_buf_phys;
PRIVATE int remap_first = 0; /* Remap drives for CD HD emulation */
_PROTOTYPE(int main, (void) );
FORWARD _PROTOTYPE( struct device *w_prepare, (int device) );
@ -95,6 +97,12 @@ PRIVATE struct driver w_dtab = {
*===========================================================================*/
PUBLIC int main()
{
long v;
v= 0;
env_parse("bios_remap_first", "d", 0, &v, 0, 1);
remap_first= v;
/* Set special disk parameters then call the generic main loop. */
driver_task(&w_dtab);
}
@ -120,7 +128,9 @@ int device;
} else {
return(NIL_DEV);
}
return(w_drive < nr_drives ? w_dv : NIL_DEV);
if (w_drive >= MAX_DRIVES || !w_wn->present)
return NIL_DEV;
return(w_dv);
}
@ -228,7 +238,7 @@ unsigned nr_req; /* length of request vector */
/* Set up an extended read or write BIOS call. */
reg86.u.b.intno = 0x13;
reg86.u.w.ax = opcode == DEV_SCATTER ? 0x4300 : 0x4200;
reg86.u.b.dl = 0x80 + w_drive;
reg86.u.b.dl = wn->drive_id;
reg86.u.w.si = (bios_buf_phys + i13e_rw_off) % HCLICK_SIZE;
reg86.u.w.ds = (bios_buf_phys + i13e_rw_off) / HCLICK_SIZE;
} else {
@ -245,7 +255,7 @@ unsigned nr_req; /* length of request vector */
reg86.u.b.ch = cylinder & 0xFF;
reg86.u.b.cl = sector | ((cylinder & 0x300) >> 2);
reg86.u.b.dh = head;
reg86.u.b.dl = 0x80 + w_drive;
reg86.u.b.dl = wn->drive_id;
}
r= sys_int86(&reg86);
@ -345,7 +355,7 @@ PRIVATE void w_init()
{
/* This routine is called at startup to initialize the drive parameters. */
int r, drive;
int r, drive, drive_id, nr_drives;
struct wini *wn;
unsigned long capacity;
struct int13ext_params {
@ -376,19 +386,31 @@ PRIVATE void w_init()
#endif
/* Get the geometry of the drives */
for (drive = 0; drive < nr_drives; drive++) {
for (drive = 0; drive < MAX_DRIVES; drive++) {
if (remap_first)
{
if (drive == 7)
drive_id= 0x80;
else
drive_id= 0x80 + drive + 1;
}
else
drive_id= 0x80 + drive;
(void) w_prepare(drive * DEV_PER_DRIVE);
wn = w_wn;
wn->drive_id= drive_id;
reg86.u.b.intno = 0x13;
reg86.u.b.ah = 0x08; /* Get drive parameters. */
reg86.u.b.dl = 0x80 + drive;
reg86.u.b.dl = drive_id;
r= sys_int86(&reg86);
if (r != OK)
panic(ME, "BIOS call failed", r);
nr_drives = !(reg86.u.w.f & 0x0001) ? reg86.u.b.dl : drive;
if (nr_drives > MAX_DRIVES) nr_drives = MAX_DRIVES;
if (drive >= nr_drives) break;
if (drive_id >= 0x80 + nr_drives) continue;
wn->present= 1;
wn->heads = reg86.u.b.dh + 1;
wn->sectors = reg86.u.b.cl & 0x3F;
@ -399,7 +421,7 @@ PRIVATE void w_init()
reg86.u.b.intno = 0x13;
reg86.u.b.ah = 0x41; /* INT 13 Extensions - Installation check */
reg86.u.w.bx = 0x55AA;
reg86.u.b.dl = 0x80 + drive;
reg86.u.b.dl = drive_id;
if (pc_at) {
r= sys_int86(&reg86);
@ -418,7 +440,7 @@ PRIVATE void w_init()
panic(ME, "sys_vircopy failed\n", r);
reg86.u.b.intno = 0x13;
reg86.u.b.ah = 0x48; /* Ext. Get drive parameters. */
reg86.u.b.dl = 0x80 + drive;
reg86.u.b.dl = drive_id;
reg86.u.w.si = bios_buf_phys % HCLICK_SIZE;
reg86.u.w.ds = bios_buf_phys / HCLICK_SIZE;