1| 2| check FD format 3| 4| Written by Yasha (ITOH Yasufumi) 5| This code is in the public domain 6| 7| $NetBSD: chkfmt.s,v 1.1 2001/09/27 10:03:27 minoura Exp $ 8 9/* FDC address */ 10#define FDC_STATUS 0xE94001 /* status register */ 11#define FDC_DATA 0xE94003 /* data register */ 12 13#define INT_STAT 0xE9C001 /* interrupt control */ 14#define INT_FDC_BIT 2 15 16/* Status Register */ 17#define NE7ST_CB_BIT 4 /* FDC busy */ 18#define NE7ST_DIO_BIT 6 /* data input/output */ 19#define NE7ST_RQM_BIT 7 /* request for master */ 20 21/* FDC command */ 22#define NE7CMD_READID 0x4A /* READ ID */ 23 24| 25| Read ID of all sectors in current track. 26| This routine expects that motor on, drive selection 27| and seek is already done. 28| 29| input: d0.b: 0 0 0 0 0 HD US1 US0 (binary) 30| output: d0.l: min # sector (N C H R (2hex)) 31| d1.l: max # sector (N C H R (2hex)) 32| destroy: 33| d0, d1 34| 35 .text 36 .even 37 .globl check_fd_format 38check_fd_format: 39 moveml %d2-%d7/%a1-%a3,%sp@- 40 41 moveb %d0,%d6 | head, drive 42 43 lea FDC_STATUS:l,%a1 44 lea %a1@(FDC_DATA-FDC_STATUS),%a2 | FDC_DATA 45 lea %a2@(INT_STAT-FDC_DATA),%a3 | INT_STAT 46 47 movew %sr,%sp@- 48 oriw #0x0700,%sr | keep out interrupts 49 moveq #INT_FDC_BIT,%d5 50 bclr %d5,%a3@ | disable FDC interrupt 51 52 jbsr read_id_sub 53 jne exit_check_format 54 movel %d3,%d2 | first sector 55 movel %d3,%d0 | sector min 56sector_is_max: 57 movel %d3,%d1 | sector max 58 59loop_read_id: 60 jbsr read_id_sub 61 jne exit_check_format 62 cmpl %d0,%d3 63 jcc sector_not_min 64 movel %d3,%d0 65sector_not_min: 66 cmpl %d3,%d1 67 jcs sector_is_max 68 cmpl %d2,%d3 69 jne loop_read_id 70 71exit_check_format: 72 bset %d5,%a3@ | enable FDC interrupt 73 movew %a7@+,%sr 74 75 tstl %d7 76 moveml %a7@+,%d2-%d7/%a1-%a3 77 jne _err_read_id 78 79 rts 80 81| 82| input: d6.b: 0 0 0 0 0 HD US1 US0 (binary) 83| a1: FDC status addr 84| a2: FDC data addr 85| interrupt must be disabled 86| output: d3.l: sector information: N C H R (2hex) 87| d7.l: status (nonzero if error) 88| Z flag: true if no error, false if error 89| destroy: 90| d3-d4, d7 91| 92read_id_sub: 93 | wait for FDC ready 94fdc_wait_ready: 95 btst #NE7ST_CB_BIT,%a1@ 96 jne fdc_wait_ready 97 98 | send READ ID command 99fdc_send_command1: 100 jbsr fdc_wait_rqm 101 jmi fdc_send_command1 102 moveb #NE7CMD_READID,%a2@ 103 104fdc_send_command2: 105 jbsr fdc_wait_rqm 106 jmi fdc_send_command2 107 moveb %d6,%a2@ | X X X X X HD US1 US0 (binary) 108 109 | receive data 110 moveq #2,%d4 111 jbsr fdc_read_bytes 112 movel %d3,%d7 | d7: FDC status: X ST0 ST1 ST2 (2hex) 113 moveq #3,%d4 114 jbsr fdc_read_bytes | d3: sector info: C H R N (2hex) 115 rorl #8,%d3 | d3: sector info: N C H R (2hex) 116 117 andil #0x00f8ffff,%d7 | check status (must be zero) 118 rts 119 120| 121| receive d4:w + 1 bytes from FDC 122| 123fdc_read_bytes: 124 asll #8,%d3 125fdc_read_loop: 126 jbsr fdc_wait_rqm 127 jpl fdc_read_loop 128 moveb %a2@,%d3 129 dbra %d4,fdc_read_bytes 130 rts 131 132fdc_wait_rqm: 133 moveb %a1@,%d3 134 jpl fdc_wait_rqm | NE7ST_RQM_BIT = 7: sign bit 135 lslb #1,%d3 | NE7ST_DIO_BIT = 6 ... move to bit #7 136 rts 137 138| 139| error 140| 141_err_read_id: 142 BOOT_ERROR("READ ID failed") 143