Changeset 169 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeTransfer.asm

Timestamp:

Aug 21, 2011, 4:39:58 PM (13 years ago)

Author:

aitotat@…

google:author:

aitotat@gmail.com

Message:

Changes to XTIDE Universal BIOS:

• Old Int 13h functions can now transfer 256 sectors per call.
• eINT 13h functions can now transfer 65535 sectors per call.

File:

• trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeTransfer.asm (modified) (8 diffs)

trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeTransfer.asm

@@ -5 +5 @@
 ; This struct must not be larger than IDEPACK without INTPACK.
 struc PIOVARS
-    .wBlockLeftAndSectorsInLastBlock:
-    .bBlocksLeft            resb    1
-    .bSectorsInLastBlock:   resb    1
+    .wBlocksLeft            resb    2
     .wBlockSize             resb    2   ; Block size in WORDs (256...32768)
     .wDataPort              resb    2
-                            resb    1
+    .bSectorsInLastBlock:   resb    1
                             resb    1   ; Offset 7 = IDEPACK.bDeviceControl
     .fnXfer                 resb    2   ; Offset to transfer function
@@ -34 +32 @@
 ALIGN JUMP_ALIGN
 IdeTransfer_StartWithCommandInAL:
+    mov     ah, [bp+IDEPACK.bSectorCountHighExt]
+
     ; Are we reading or writing?
     test    al, 16  ; Bit 4 is cleared on all the read commands but set on 3 of the 4 write commands
@@ -42 +42 @@
     ; Prepare to read data to ESSI
     mov     bx, g_rgfnPioRead
-    call    InitializePiovarsToSSBPfromIdepackInSSBP
+    mov     al, [bp+IDEPACK.bSectorCount]
+    call    InitializePiovarsInSSBPwithSectorCountInAX
     xchg    si, di
-%ifdef USE_186
-    push    ReadFromDriveToESDI
-    jmp     Registers_NormalizeESDI
-%else
     call    Registers_NormalizeESDI
-    jmp     SHORT ReadFromDriveToESDI
-%endif
+    jmp     SHORT ReadFromDrive
 
 ALIGN JUMP_ALIGN
 .PrepareToWriteDataFromESSI:
     mov     bx, g_rgfnPioWrite
-    call    InitializePiovarsToSSBPfromIdepackInSSBP
+    mov     al, [bp+IDEPACK.bSectorCount]
+    call    InitializePiovarsInSSBPwithSectorCountInAX
     call    Registers_NormalizeESSI
-    ; Fall to WriteToDriveFromESSI
-
-
-;--------------------------------------------------------------------
-; WriteToDriveFromESSI
+    ; Fall to WriteToDrive
+
+
+;--------------------------------------------------------------------
+; WriteToDrive
 ;   Parameters:
 ;       DS:DI:  Ptr to DPT (in RAMVARS segment)
@@ -73 +70 @@
 ;       AL, BX, CX, DX, SI, ES
 ;--------------------------------------------------------------------
-WriteToDriveFromESSI:
+WriteToDrive:
     ; Always poll when writing first block (IRQs are generated for following blocks)
     mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_DRQ, FLG_STATUS_DRQ)
@@ -81 +78 @@
 .WriteNextBlock:
     mov     dx, [bp+PIOVARS.wDataPort]
-    dec     BYTE [bp+PIOVARS.bBlocksLeft]       ; Transferring last (possibly partial) block?
+    dec     WORD [bp+PIOVARS.wBlocksLeft]       ; Transferring last (possibly partial) block?
     jz      SHORT .XferLastBlock                ;  If so, jump to transfer
     mov     cx, [bp+PIOVARS.wBlockSize]         ; Load block size in WORDs
     call    [bp+PIOVARS.fnXfer]                 ; Transfer full block
+
+    ; Normalize pointer when necessary
+    mov     ax, si
+    shr     ax, 1                               ; WORD offset
+    add     ax, [bp+PIOVARS.wBlockSize]
+    jns     SHORT .WaitUntilReadyToTransferNextBlock
+    call    Registers_NormalizeESSI
+
+ALIGN JUMP_ALIGN
+.WaitUntilReadyToTransferNextBlock:
 %ifdef USE_186
     push    .WriteNextBlock
@@ -110 +117 @@
 
 ;--------------------------------------------------------------------
-; ReadFromDriveToESDI
+; ReadFromDrive
 ;   Parameters:
 ;       ES:DI:  Normalized ptr to buffer to recieve data
@@ -124 +131 @@
 ;--------------------------------------------------------------------
 ALIGN JUMP_ALIGN
-ReadFromDriveToESDI:
+ReadFromDrive:
     ; Wait until drive is ready to transfer
     xchg    di, si                              ; DS:DI now points DPT
     call    IdeWait_IRQorDRQ                    ; Wait until ready to transfer
-    jc      SHORT WriteToDriveFromESSI.ReturnWithTransferErrorInAH
+    jc      SHORT WriteToDrive.ReturnWithTransferErrorInAH
     xchg    si, di                              ; ES:DI now points buffer
 
     ; Transfer full or last (possible partial) block
     mov     dx, [bp+PIOVARS.wDataPort]
-    dec     BYTE [bp+PIOVARS.bBlocksLeft]
+    dec     WORD [bp+PIOVARS.wBlocksLeft]
     jz      SHORT .XferLastBlock
     mov     cx, [bp+PIOVARS.wBlockSize]         ; Load block size in WORDs
-%ifdef USE_186
-    push    ReadFromDriveToESDI
-    jmp     [bp+PIOVARS.fnXfer]
-%else
     call    [bp+PIOVARS.fnXfer]                 ; Transfer full block
-    jmp     SHORT ReadFromDriveToESDI                   ; Loop while blocks left
-%endif
+
+    ; Normalize pointer when necessary
+    mov     ax, di
+    shr     ax, 1                               ; WORD offset
+    add     ax, [bp+PIOVARS.wBlockSize]
+    jns     SHORT ReadFromDrive
+%ifdef USE_186
+    push    ReadFromDrive
+    jmp     Registers_NormalizeESDI
+%else
+    call    Registers_NormalizeESDI
+    jmp     SHORT ReadFromDrive                 ; Loop while blocks left
+%endif
+
 
 ALIGN JUMP_ALIGN
@@ -155 +170 @@
 
 ;--------------------------------------------------------------------
-; InitializePiovarsToSSBPfromIdepackInSSBP
-;   Parameters:
+; InitializePiovarsInSSBPwithSectorCountInAX
+;   Parameters:
+;       AX:     Number of sectors to transfer (1...65535)
 ;       BX:     Offset to transfer function lookup table
 ;       DS:DI:  Ptr to DPT (in RAMVARS segment)
-;       SS:BP:  Ptr to IDEPACK
-;   Returns:
 ;       SS:BP:  Ptr to PIOVARS
+;   Returns:
+;       Nothing
 ;   Corrupts registers:
 ;       AX, BX, CX, DX
 ;--------------------------------------------------------------------
 ALIGN JUMP_ALIGN
-InitializePiovarsToSSBPfromIdepackInSSBP:
+InitializePiovarsInSSBPwithSectorCountInAX:
     ; Store number of blocks to transfer
-    eMOVZX  cx, BYTE [di+DPT_ATA.bSetBlock]     ; Block size in sectors, zero CH
-    eMOVZX  ax, BYTE [bp+IDEPACK.bSectorCount]  ; AX = sectors to transfer (1...128)
-    div     cl          ; AL = Full blocks to transfer
-    test    ah, ah      ; AH = Sectors in partial block
+    eMOVZX  cx, BYTE [di+DPT_ATA.bSetBlock]     ; Block size in sectors
+    xor     dx, dx      ; DX:AX = Sectors to transfer (1...65535)
+    div     cx          ; AX = Full blocks to transfer
+    test    dx, dx
+    mov     dh, cl      ; DH = Full block size if no partial blocks to transfer
     jz      SHORT .NoPartialBlocksToTransfer
-    inc     ax          ; Add partial block to total block count
-    SKIP2B  dx          ; Skip mov ah, cl
+    inc     ax          ; Partial block
+    mov     dh, dl      ; DH = Size of partial block in sectors
 .NoPartialBlocksToTransfer:
-    mov     ah, cl      ; Full block size if no partial blocks to transfer
-    mov     [bp+PIOVARS.wBlockLeftAndSectorsInLastBlock], ax
+    mov     [bp+PIOVARS.wBlocksLeft], ax
+    mov     [bp+PIOVARS.bSectorsInLastBlock], dh
 
     ; Store block size in WORDs