ubee: Further floppy driver bashing

512 bytes/sector, double sided

Also set the step to 6ms

diff --git a/Kernel/platform-ubee/devfd.c b/Kernel/platform-ubee/devfd.c
index 37d94c8..3eba9ae 100644 (file)
--- a/Kernel/platform-ubee/devfd.c
+++ b/Kernel/platform-ubee/devfd.c
@@ -9,8 +9,8 @@
 #define OPDIR_READ     1
 #define OPDIR_WRITE    2
 
-#define FD_READ                0x80    /* 2797 needs 0x88, 1797 needs 0x80 */
-#define FD_WRITE       0xA0    /* Likewise A8 v A0 */
+#define FD_READ                0x80
+#define FD_WRITE       0xA0
 
 __sfr __at 0x58        fdc_devsel;
 
@@ -24,9 +24,9 @@ static uint8_t fd_tab[MAX_FD] = { 0xFF, 0xFF, 0xFF, 0xFF };
  */
 
 /* Standard FDC */
-static uint8_t selmap[4] = { 0x01, 0x02, 0x03, 0x04 };
-#define FDC_SIDE1      0x08
-#define FDC_DOUBLE     0x10
+static uint8_t selmap[4] = { 0x00, 0x01, 0x02, 0x03 };
+#define FDC_SIDE1      0x04
+#define FDC_DOUBLE     0x08
 #define FDC_SINGLE     0x00
 
 /* DreamDisc FDC */
@@ -64,30 +64,24 @@ static int fd_transfer(uint8_t minor, bool is_read, uint8_t rawflag)
     dptr = (uint16_t)udata.u_buf->bf_data;
     block = udata.u_buf->bf_blk;
 
-    /* Q: should we go with 512 bytes/sector format ? */
     cmd[0] = is_read ? FD_READ : FD_WRITE;
-    cmd[1] = block / 9;                /* 2 sectors per block */
-    cmd[2] = ((block % 9) << 1) + 1;   /*eww.. */
+    /* Double sided assumed FIXME */
+    cmd[1] = block / 20;
+    /* floppy.s will sort the side out */
+    cmd[2] = ((block % 20) << 1) + 1;
     cmd[3] = is_read ? OPDIR_READ: OPDIR_WRITE;
     cmd[4] = dptr & 0xFF;
     cmd[5] = dptr >> 8;
 
-    while (ct < 2) {
-        for (tries = 0; tries < 4 ; tries++) {
-            err = fd_operation(cmd, driveptr);
-            if (err == 0)
-                break;
-            if (tries > 1)
-                fd_reset(driveptr);
-        }
-        /* FIXME: should we try the other half and then bale out ? */
-        if (tries == 4)
-            goto bad;
-        cmd[5]++;      /* Move on 256 bytes in the buffer */
-        cmd[2]++;      /* Next sector for 2nd block */
-        ct++;
-    }
-    return 1;
+    for (tries = 0; tries < 4 ; tries++) {
+        err = fd_operation(cmd, driveptr);
+        if (err == 0)
+            break;
+        if (tries > 1)
+            fd_reset(driveptr);
+   }
+   if (tries != 4)
+       return 1;
 bad:
     kprintf("fd%d: error %x\n", minor, err);
 bad2:

diff --git a/Kernel/platform-ubee/floppy.s b/Kernel/platform-ubee/floppy.s
index 9c61c03..835a78d 100644 (file)
--- a/Kernel/platform-ubee/floppy.s
+++ b/Kernel/platform-ubee/floppy.s
@@ -2,26 +2,22 @@
 ;      Core floppy routines for the TRS80 1791 FDC
 ;      Based on the 6809 code
 ;
-;      FIXME: better drive spin up wait
 ;      FIXME: double sided media
 ;      FIXME: correct step rates (per drive ?)
 ;      FIXME: precompensation
-;              - not on single density
-;              - track dependant for double density based on trsdos dir pos
-;
+;      FIXME: density, size etc
 ;
        .globl _fd_reset
        .globl _fd_operation
        .globl _fd_motor_on
-       .globl _fd_motor_off
        .globl fd_nmi_handler
 
-FDCREG .equ    0xF0
-FDCTRK .equ    0xF1
-FDCSEC .equ    0xF2
-FDCDATA        .equ    0xF3
-FDCCTRL        .equ    0xF4
-FDCINT .equ    0xE4
+FDCREG .equ    0x40
+FDCTRK .equ    0x41
+FDCSEC .equ    0x42
+FDCDATA        .equ    0x43
+FDCCTRL        .equ    0x48
+
 ;
 ;      interrupt register reports 0x80 for interrut, 0x40 for drq
 ;      (0x20 is the unrelated reset button)
@@ -54,7 +50,7 @@ nap:  dec     bc
        jr      nz, nap
        ret
 ;
-;      The motor off logic is driven from hardware
+;      NMI logic for DreamDisc
 ;
 fd_nmi_handler:
        push    af
@@ -62,10 +58,6 @@ fd_nmi_handler:
        ld      a, (fdc_active)
        or      a
        jr      z, boring_nmi
-       xor     a
-       out     (FDCINT), a
-       ld      bc, #100
-       call    nap
        pop     bc
        pop     af
        pop     af              ; discard return address
@@ -113,6 +105,30 @@ waitdisk_l:
 ;      DE points to the track reg copy
 ;
 fdsetup:
+;
+;      Are we on side 0 or side 1 ?
+;
+       ld      a, SECTOR(ix)
+       cp      #11
+       jr      c, side0
+;
+;      Set up for side 1 access
+;
+       sub     #10
+       ld      SECTOR(ix), a
+       ld      a, (fdcctrl)
+       set     2, a            ; correct for standard FDC not DreamDisc
+       jr      side1
+side0:
+       ld      a, (fdcctrl)
+       res     2, a
+side1:
+;
+;      FIXME: do we need to precompensation ?
+;
+       ld      (fdcctrl), a
+       out     (FDCCTRL), a
+
        ld      a, (de)
        out     (FDCTRK), a
        cp      TRACK(ix)
@@ -128,7 +144,8 @@ fdsetup:
        ;
        ;       Need to seek the disk
        ;
-       ld      a, #0x18        ; seek
+       ld      a, #0x19        ; seek at 6ms steps. Slightly conservative
+                               ; to allow for older drives
        out     (FDCREG), a
        ld      b, #100
 seekwt:        djnz    seekwt
@@ -147,15 +164,7 @@ setuptimeout:                      ; NE = bad
 fdiosetup:
        ld      a, TRACK(ix)
        ld      (de), a         ; save track
-;      cmp     #22             ; FIXME
-;      jr      nc, noprecomp
-;      ld      a, (fdcctrl)
-;      or      #0x10           ; Precomp on
-;      jr      precomp1
-;noprecomp:
-       ld      a, (fdcctrl)
-;precomp1:
-       out     (FDCCTRL), a
+
        ld      a, SECTOR(ix)
        out     (FDCSEC), a
        in      a, (FDCREG)     ; Clear any pending status
@@ -196,7 +205,7 @@ fdxferdone2:
 ;
 fdio_in:
        ld      e, #0x16                ; bits to check
-       ld      bc, #FDCDATA            ; 256 bytes/sector, c is our port
+       ld      bc, #FDCDATA            ; 512 bytes/sector, c is our port
 fdio_inl:
        in      a, (FDCREG)
        and     e
@@ -208,6 +217,10 @@ fdio_inbyte:
        out     (FDCCTRL), a            ; stalls
        ini
        jr      nz, fdio_inbyte
+fdio_inbyte2:
+       out     (FDCCTRL), a            ; stalls
+       ini
+       jr      nz, fdio_inbyte2
        jr      fdxferdone
 
 ;
@@ -226,10 +239,6 @@ fdio_outl:
        in      a, (FDCREG)             ; No longer busy ??
        rra
        jr      nc, fdxferbad           ; Bugger... 
-       ld      a, #0xC0                ; Turn on magic floppy NMI interface
-       out     (FDCINT), a
-       ld      b, #50                  ; Spin for it
-spin1: djnz    spin1
        ld      b, (hl)                 ; Next byte
        inc     hl
 fdio_waitlock:
@@ -278,7 +287,7 @@ _fd_reset:
        out     (FDCSEC), a
        xor     a
        out     (FDCTRK), a
-       ld      a, #0x0C
+       ld      a, #0x0D        ; use 6ms stepping
        out     (FDCREG), a     ; restore
        ld      a, #0xFF
        ld      (hl), a         ; Zap track pointer
@@ -320,13 +329,12 @@ _fd_operation:
 ;      C interface fd_motor_on(uint16_t drivesel)
 ;
 ;      Selects this drive and turns on the motors. Also pass in the
-;      choice of density
+;      choice of density. For the standard uBee disk that is
 ;
-;      bits 0-3:       select that drive
-;      bit 4:          side (must rewrite each drive change)
-;      bit 5:          precompensation (not set here but in the I/O ops)
-;      bit 6:          synchronize I/O by stalling the CPU (don't set this)
-;      bit 7:          set for double density (MFM)
+;      bits 0-1:       select drive
+;      bit 2:          side (must rewrite each drive change)
+;                      (handled elsewhere)
+;      bit 3:          density (set = DD)
 ;
 ;
 _fd_motor_on:
@@ -335,14 +343,10 @@ _fd_motor_on:
        push    hl
        push    de
        ;
-       ;       Select drive B, turn on motor if needed
+       ;       Select drive B
        ;
-       ld      a,(motor_running)       ; nothing selected
-       or      a
-       jr      z, notsel
-
        cp      l
-       jr      z,  motor_was_on
+       jr      z,  was_selected
 ;
 ;      Select our drive
 ;
@@ -359,31 +363,12 @@ notsel:
 ;
 ;      All is actually good
 ;
-motor_was_on:
+was_selected:
        ld      hl, #0
        ret
 
-;
-;      C interface fd_motor_off(void)
-;
-;      Turns off the drive motors, deselects all drives
-;
-_fd_motor_off:
-       ld      a, (motor_running)
-       or      a
-       ret     z
-       ; Should we seek to track 0 ?
-       in      a, (FDCCTRL)
-       and     #0xF0           ; clear drive bits
-       out     (FDCCTRL), a
-       xor     a
-       ld      (motor_running), a
-       ret
-
 curdrive:
        .db     0xff
-motor_running:
-       .db     0
 fdcctrl:
        .db     0
 fdc_active: