149 lines
2.9 KiB
ArmAsm
149 lines
2.9 KiB
ArmAsm
|
|
|
| check FD format
|
|
|
|
|
| Written by Yasha (ITOH Yasufumi)
|
|
| This code is in the public domain
|
|
|
|
|
| $NetBSD: chkfmt.s,v 1.2 2001/06/12 16:57:28 minoura Exp $
|
|
|
|
/* FDC address */
|
|
#define FDC_STATUS 0xE94001 /* status register */
|
|
#define FDC_DATA 0xE94003 /* data register */
|
|
|
|
#define INT_STAT 0xE9C001 /* interrupt control */
|
|
#define INT_FDC_BIT 2
|
|
|
|
/* Status Register */
|
|
#define NE7ST_CB_BIT 4 /* FDC busy */
|
|
#define NE7ST_DIO_BIT 6 /* data input/output */
|
|
#define NE7ST_RQM_BIT 7 /* request for master */
|
|
|
|
/* FDC command */
|
|
#define NE7CMD_READID 0x4A /* READ ID */
|
|
|
|
|
|
|
| Read ID of all sectors in current track.
|
|
| This routine expects that motor on, drive selection
|
|
| and seek is already done.
|
|
|
|
|
| input: %d0.b: 0 0 0 0 0 HD US1 US0 (binary)
|
|
| output: %d0.l: min # sector (N C H R (2hex))
|
|
| %d1.l: max # sector (N C H R (2hex))
|
|
| destroy:
|
|
| %d0, %d1
|
|
|
|
|
.text
|
|
.even
|
|
.globl check_fd_format
|
|
check_fd_format:
|
|
moveml %d2-%d7/%a1-%a3,%sp@-
|
|
|
|
moveb %d0,%d6 | head, drive
|
|
|
|
lea FDC_STATUS:l,%a1
|
|
lea %a1@(FDC_DATA-FDC_STATUS),%a2 | FDC_DATA
|
|
lea %a2@(INT_STAT-FDC_DATA),%a3 | INT_STAT
|
|
|
|
movew %sr,%sp@-
|
|
oriw #0x0700,%sr | keep out interrupts
|
|
bclr #INT_FDC_BIT,%a3@ | disable FDC interrupt
|
|
|
|
jbsr read_id_sub
|
|
jne exit_check_format
|
|
movel %d3,%d2 | first sector
|
|
movel %d3,%d0 | sector min
|
|
movel %d3,%d1 | sector max
|
|
|
|
loop_read_id:
|
|
jbsr read_id_sub
|
|
jne exit_check_format
|
|
cmpl %d0,%d3
|
|
jcc sector_not_min
|
|
movel %d3,%d0
|
|
sector_not_min:
|
|
cmpl %d3,%d1
|
|
jcc sector_not_max
|
|
movel %d3,%d1
|
|
sector_not_max:
|
|
cmpl %d2,%d3
|
|
jne loop_read_id
|
|
|
|
exit_check_format:
|
|
bset #INT_FDC_BIT,%a3@ | enable FDC interrupt
|
|
movew %a7@+,%sr
|
|
|
|
tstl %d7
|
|
moveml %a7@+,%d2-%d7/%a1-%a3
|
|
jne _err_read_id
|
|
|
|
rts
|
|
|
|
|
|
|
| input: %d6.b: 0 0 0 0 0 HD US1 US0 (binary)
|
|
| %a1: FDC status addr
|
|
| %a2: FDC data addr
|
|
| interrupt must be disabled
|
|
| output: %d3.l: sector information: N C H R (2hex)
|
|
| %d7.l: status (nonzero if error)
|
|
| Z flag: true if no error, false if error
|
|
| destroy:
|
|
| %d3-%d5, %d7
|
|
|
|
|
read_id_sub:
|
|
| wait for FDC ready
|
|
fdc_wait_ready:
|
|
btst #NE7ST_CB_BIT,%a1@
|
|
jne fdc_wait_ready
|
|
|
|
| send READ ID command
|
|
moveq #NE7CMD_READID,%d4
|
|
jbsr fdc_send_command
|
|
moveb %d6,%d4 | X X X X X HD US1 US0 (binary)
|
|
jbsr fdc_send_command
|
|
|
|
| receive data
|
|
moveq #2,%d4
|
|
jbsr fdc_read_bytes
|
|
movel %d3,%d7 | %d7: FDC status: X ST0 ST1 ST2 (2hex)
|
|
moveq #3,%d4
|
|
jbsr fdc_read_bytes | %d3: sector info: C H R N (2hex)
|
|
rorl #8,%d3 | %d3: sector info: N C H R (2hex)
|
|
|
|
andil #0x00f8ffff,%d7 | check status (must be zero)
|
|
rts
|
|
|
|
|
|
|
| send one byte of command
|
|
|
|
|
fdc_send_command:
|
|
jbsr fdc_wait_rqm
|
|
jne fdc_send_command
|
|
moveb %d4,%a2@
|
|
rts
|
|
|
|
|
|
|
| receive %d4:w+1 bytes from FDC
|
|
|
|
|
fdc_read_bytes:
|
|
asll #8,%d3
|
|
fdc_read_loop:
|
|
jbsr fdc_wait_rqm
|
|
jeq fdc_read_loop
|
|
moveb %a2@,%d3
|
|
dbra %d4,fdc_read_bytes
|
|
rts
|
|
|
|
fdc_wait_rqm:
|
|
moveb %a1@,%d5
|
|
| btst #NE7ST_RQM_BIT,%d5
|
|
| jeq fdc_wait_rqm
|
|
jpl fdc_wait_rqm | NE7ST_RQM_BIT = 7: sign bit
|
|
btst #NE7ST_DIO_BIT,%d5
|
|
rts
|
|
|
|
|
|
|
| error
|
|
|
|
|
_err_read_id:
|
|
BOOT_ERROR1("READ ID failed")
|