Changeset 200 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs

Timestamp:

Nov 22, 2011, 8:38:36 AM (13 years ago)

Author:

gregli@…

google:author:

gregli@hotmail.com

Message:

Added logic to skip scanning COM ports if a COM port was already found during the normal detection process, to avoid finding the same serial drive twice and preseting the OS with two drives which in reality point to the same physical file on the server. Also added logic to skip scanning for the slave serial drive if the master was not found. And various small optimizations.

Location:

trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs

Files:

• AccessDPT.asm (modified) (1 diff)
• FindDPT.asm (modified) (9 diffs)

trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/AccessDPT.asm

@@ -124 +124 @@
 .ReturnPointerToDRVPARAMS:
     ret
+
+;--------------------------------------------------------------------
+; AccessDPT_GetUnshiftedAddressModeToALZF
+;   Parameters:
+;       DS:DI:  Ptr to Disk Parameter Table
+;   Returns:
+;       AL:     Addressing Mode (L-CHS, P-CHS, LBA28, LBA48) 
+;               unshifted (still shifted where it is in bFlagsLow)
+;       ZF:     Set based on value in AL
+;   Corrupts registers:
+;       AL
+;--------------------------------------------------------------------
+; 
+; Converted to a macro since only called in two places, and the call/ret overhead 
+; is not worth it for these two instructions (4 bytes total)
+;
+%macro AccessDPT_GetUnshiftedAddressModeToALZF 0
+    mov     al, [di+DPT.bFlagsLow]
+    and     al, MASKL_DPT_ADDRESSING_MODE
+%endmacro
+
+        

trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/FindDPT.asm

@@ -50 +50 @@
     ret
 
-
 ;--------------------------------------------------------------------
 ; Finds Disk Parameter Table for
@@ -67 +66 @@
 ;   Corrupts registers:
 ;       SI
-;--------------------------------------------------------------------
-ALIGN JUMP_ALIGN
-FindDPT_ToDSDIForIdeMasterAtPortDX:
+;
+; Converted to macros since there is only once call site for each of these
+;
+;--------------------------------------------------------------------
+    
+%macro FindDPT_ToDSDIForIdeMasterAtPortDX 0
     mov     si, IterateToMasterAtPortCallback
-    jmp     SHORT IterateAllDPTs
-
-ALIGN JUMP_ALIGN
-FindDPT_ToDSDIForIdeSlaveAtPortDX:
+    call    IterateAllDPTs
+%endmacro
+
+%macro FindDPT_ToDSDIForIdeSlaveAtPortDX 0
     mov     si, IterateToSlaveAtPortCallback
-    jmp     SHORT IterateAllDPTs
-
+    call    IterateAllDPTs
+%endmacro
+
+        
 ;--------------------------------------------------------------------
 ; Iteration callback for finding DPT using
@@ -113 +117 @@
     jne     SHORT ReturnWrongDPT
     mov     dl, ch                              ; Return drive number in DL
+
+ReturnRightDPT:
     stc                                         ; Set CF since wanted DPT
     ret
@@ -118 +124 @@
 
 ;--------------------------------------------------------------------
-; IterateToDptWithInterruptInServiceFlagSet
+; IterateToDptWithFlagsHighSet:
 ;   Parameters:
 ;       DS:DI:  Ptr to DPT to examine
+;       AL:     Bit in bFlagsHigh to test
 ;   Returns:
 ;       CF:     Set if wanted DPT found
@@ -128 +135 @@
 ;--------------------------------------------------------------------
 ALIGN JUMP_ALIGN
-IterateToDptWithInterruptInServiceFlagSet:
-    test    BYTE [di+DPT.bFlagsHigh], FLGH_DPT_INTERRUPT_IN_SERVICE
-    jz      SHORT ReturnWrongDPT
-    stc                                     ; Set CF since wanted DPT
-    ret
+IterateToDptWithFlagsHighSet:
+    test    BYTE [di+DPT.bFlagsHigh], al    ; Clears CF (but we need the clc below anyway callers above)
+    jnz     SHORT ReturnRightDPT
+
 ReturnWrongDPT:
     clc                                     ; Clear CF since wrong DPT
     ret
 
-
 ;--------------------------------------------------------------------
 ; FindDPT_ToDSDIforInterruptInService
+; FindDPT_ToDSDIforSerialDevice
 ;   Parameters:
 ;       DS:     RAMVARS segment
@@ -147 +153 @@
 ;               Cleared if DPT not found
 ;   Corrupts registers:
-;       SI
-;--------------------------------------------------------------------
-ALIGN JUMP_ALIGN
+;       SI, AX, BX (for SerialDevice only)
+;--------------------------------------------------------------------
+ALIGN JUMP_ALIGN
+        
+%ifdef MODULE_SERIAL
+FindDPT_ToDSDIforSerialDevice:  
+    mov     al, FLGH_DPT_SERIAL_DEVICE
+
+    SKIP2B  bx
+%endif
+        
+; do not align due to SKIP2B above
 FindDPT_ToDSDIforInterruptInService:
-    mov     si, IterateToDptWithInterruptInServiceFlagSet
+    mov     al, FLGH_DPT_INTERRUPT_IN_SERVICE
+
+    mov     si, IterateToDptWithFlagsHighSet
     ; Fall to IterateAllDPTs
-
 
 ;--------------------------------------------------------------------
@@ -166 +182 @@
 ;       DS:DI:      Ptr to wanted DPT (if found)
 ;       CF:         Set if wanted DPT found
-;                   Cleared if DPT not found
-;                   Unchanged if no drives
+;                   Cleared if DPT not found, or no DPTs present
 ;   Corrupts registers:
 ;       Nothing unless corrupted by callback function
@@ -175 +190 @@
     push    cx
     mov     cx, [RAMVARS.wDrvCntAndFirst]
-    jcxz    .AllDptsIterated            ; Return if no drives
+    jcxz    .NotFound                   ; Return if no drives
     mov     di, RAMVARS_size            ; Point DS:DI to first DPT
 ALIGN JUMP_ALIGN
@@ -185 +200 @@
     dec     cl                          ; Decrement drives left
     jnz     SHORT .LoopWhileDPTsLeft
+.NotFound:      
     clc                                 ; Clear CF since DPT not found
 ALIGN JUMP_ALIGN