Changeset 588 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH1Eh_XTCF.asm

Timestamp:

Jun 3, 2015, 12:30:54 PM (10 years ago)

Author:

krille_n_@…

google:author:

krille_n_@hotmail.com

Message:

Changes:

• Fixed a bug in AH24h_HSetBlocks.asm from r550. Trying to set a too large block size with an XT-CF card in DMA transfer mode would corrupt the stack.
• Fixed a bug from r545 where the list of devices under g_szDeviceTypeValues in Strings.asm was no longer up to date causing the boot menu to display the wrong string for devices numbered higher than DEVICE_8BIT_XTCF_PIO8.
• Made some fairly significant changes to the XT-CF code to reduce size. Two changes in functionality; 1) Added a simple check to validate the request for a change of the XT-CF transfer mode. 2) Changing transfer mode to use DMA no longer calls AH24h_SetBlockSize if the block size already is within the limits of DMA transfers. UNTESTED
• XTIDECFG now clears IDEVARS.bIRQ when changing IDE controller to a serial device to keep the boot menu from displaying it since the serial device doesn't use IRQs at all.
• Other minor optimizations.

File:

• trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH1Eh_XTCF.asm (modified) (7 diffs)

trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH1Eh_XTCF.asm

@@ -65 +65 @@
     ; IS_THIS_DRIVE_XTCF. We check this for all commands.
     call    AccessDPT_IsThisDeviceXTCF
-    jne     SHORT .XTCFnotFound
+    jc      SHORT .XTCFnotFound
     and     ax, 0FFh                    ; Subcommand now in AX (clears AH and CF)
     jz      SHORT .XTCFfound            ; Sub-function IS_THIS_DRIVE_XTCF (=0)
@@ -111 +111 @@
     ;       Selected transfer mode is stored in BIOS variable (DPT_ATA.bDevice).
 
-    ; Note that when selecting 'DEVICE_8BIT_XTCF_PIO8_WITH_BIU_OFFLOAD' mode,
+    ; Note that when selecting 'XTCF_8BIT_PIO_MODE_WITH_BIU_OFFLOAD' mode,
     ; the ATA device (i.e. CompactFlash card) will operate in 8-bit mode, but
     ; data will be transferred from its data register using 16-bit CPU instructions
@@ -122 +122 @@
     ; Also note that some machines, noteably the Olivetti M24 (also known as
     ; the AT&T PC6300 and Xerox 6060), have hardware errors in the BIU logic,
-    ; resulting in reversed byte ordering.  Therefore, mode DEVICE_8BIT_PIO is
+    ; resulting in reversed byte ordering.  Therefore, XTCF_8BIT_PIO_MODE is
     ; the default transfer mode for best system compatibility.
 
+
+    ; Is requested mode valid?
+    cmp     al, 3                       ; Valid modes are 0...3
+    ja      SHORT ProcessXTCFsubcommandFromAL.AH1Eh_LoadInvalidCommandToAHandSetCF
+
+    ; Convert mode to XT-CF device type (see RomVars.inc and XTCF.inc for full details)
+    eSHL_IM al, 1                       ; Shift requested mode
+    add     al, XTCF_DEVICE_OFFSET      ; Add the device offset (already shifted)
+    mov     [di+DPT_ATA.bDevice], al    ; Set the new mode (or device actually)
+
+    cmp     al, DEVICE_8BIT_XTCF_PIO16_WITH_BIU_OFFLOAD
+    je      SHORT AH23h_Disable8bitPioMode
+
+    ; We always need to enable 8-bit mode since 16-bit mode is restored
+    ; when controller is reset (AH=00h or 0Dh)
+
+    cmp     al, DEVICE_8BIT_XTCF_DMA
+    jne     SHORT AH23h_Enable8bitPioMode
+
+    ; DMA transfers have limited block size
+    mov     al, XTCF_DMA_MODE_MAX_BLOCK_SIZE
+    cmp     [di+DPT_ATA.bBlockSize], al
+    jbe     SHORT AH23h_Enable8bitPioMode   ; No need to limit block size
+    call    AH24h_SetBlockSize
+    jmp     SHORT AH23h_Enable8bitPioMode
+
+
+%if 0
     ; We always need to enable 8-bit mode since 16-bit mode is restored
     ; when controller is reset (AH=00h or 0Dh)
@@ -134 +162 @@
     dec     ax                      ; XTCF_8BIT_PIO_MODE_WITH_BIU_OFFLOAD = 1
     jz      SHORT .Set8bitPioModeWithBIUOffload
-    dec     ax
+    dec     ax                      ; XTCF_16BIT_PIO_WITH_BIU_OFFLOAD = 2
     jz      SHORT .Set16bitPioModeWithBIUOffload
 
-    ; XTCF_DMA_MODE = 2 (allow 3 as well for more optimized code)
+    ; XTCF_DMA_MODE = 3
     mov     BYTE [di+DPT_ATA.bDevice], DEVICE_8BIT_XTCF_DMA
 
@@ -161 +189 @@
     mov     [di+DPT_ATA.bDevice], al
     ret
+%endif ; 0
 
 
@@ -168 +197 @@
 ;       DS:DI:  Ptr to DPT (in RAMVARS segment)
 ;   Returns:
-;       AX:     XT-CF mode (XTCF_8BIT_PIO_MODE, XTCF_8BIT_PIO_MODE_WITH_BIU_OFFLOAD or XTCF_DMA_MODE)
+;       AX:     XT-CF mode (XTCF_8BIT_PIO_MODE, XTCF_8BIT_PIO_MODE_WITH_BIU_OFFLOAD, XTCF_16BIT_PIO_WITH_BIU_OFFLOAD or XTCF_DMA_MODE)
 ;       CF:     Clear
 ;   Corrupts registers:
@@ -174 +203 @@
 ;--------------------------------------------------------------------
 AH1Eh_GetCurrentXTCFmodeToAX:
+    mov     ax, -XTCF_DEVICE_OFFSET & 0FFh
+    add     al, [di+DPT_ATA.bDevice]
+    shr     al, 1
+    ret
+
+%if 0
     mov     al, [di+DPT_ATA.bDevice]
     shr     al, 1
     cbw
-    sub     al, DEVICE_8BIT_XTCF_PIO8 >> 1
-    ret
+    sub     al, XTCF_DEVICE_OFFSET >> 1
+    ret
+%endif ; 0