Changeset 540 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeIrq.asm

Timestamp:

Apr 13, 2013, 3:40:27 PM (11 years ago)

Author:

aitotat@…

google:author:

aitotat@gmail.com

Message:

Changes to XTIDE Universal BIOS:

• Improved interrupt handling: INT 15h AH=91h is no longer called if AH=90h was not called.

File:

• trunk/XTIDE_Universal_BIOS/Src/Device/IDE/IdeIrq.asm (modified) (2 diffs)

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

@@ -33 +33 @@
 IdeIrq_WaitForIRQ:
     push    ds
-
     LOAD_BDA_SEGMENT_TO ds, ax, !       ; Zero AX
     mov     ah, OS_HOOK_DEVICE_BUSY     ; Hard disk busy (AX=9000h)
     cli                                 ; Disable interrupts
-    cmp     al, [BDA.bHDTaskFlg]        ; Task flag already set?
-    jc      SHORT .ReturnFromWaitNotify ;  If so, skip OS notification
+    dec     BYTE [BDA.bHDTaskFlg]       ; Clear to zero if still waiting for IRQ
+    pop     ds
+    jnz     SHORT .ReturnFromWaitNotify ; IRQ already! (CompactFlash was faster than CPU)   
     int     BIOS_SYSTEM_INTERRUPT_15h   ; OS hook, device busy
 
 .ReturnFromWaitNotify:
     sti                                 ; Enable interrupts
-    pop     ds
     ret
 
@@ -61 +60 @@
 ALIGN JUMP_ALIGN
 IdeIrq_InterruptServiceRoutineForIrqs2to7:
-    push    di
     push    ax
-    call    AcknowledgeIdeInterruptAndSetTaskFlag
+    mov     al, COMMAND_END_OF_INTERRUPT
 
-    mov     al, COMMAND_END_OF_INTERRUPT
+%ifdef USE_AT
     jmp     SHORT AcknowledgeMasterInterruptController
-
 
 ALIGN JUMP_ALIGN
 IdeIrq_InterruptServiceRoutineForIrqs8to15:
-    push    di
     push    ax
-    call    AcknowledgeIdeInterruptAndSetTaskFlag
-
     mov     al, COMMAND_END_OF_INTERRUPT
     out     SLAVE_8259_COMMAND_out, al  ; Acknowledge Slave 8259
+    JMP_DELAY
 AcknowledgeMasterInterruptController:
+%endif ; USE_AT
+
     out     MASTER_8259_COMMAND_out, al ; Acknowledge Master 8259
 
+    ; Set Task Flag
+    push    ds
+    LOAD_BDA_SEGMENT_TO ds, ax, !       ; Clear AL and CF for INT 15h
+    dec     BYTE [BDA.bHDTaskFlg]       ; Set task flag (or clear if IRQ occurred before call to INT 15h AH=90h)
+    sti                                 ; Enable interrupts
+    pop     ds
+
     ; Issue Int 15h, function AX=9100h (Interrupt ready)
-    clc                                 ; Must be called with CF clear
-    mov     ax, OS_HOOK_DEVICE_POST<<8  ; Interrupt ready, device 0 (HD)
+    jz      SHORT .DoNotPostSinceIrqOccurredBeforeWait
+    mov     ah, OS_HOOK_DEVICE_POST     ; Interrupt ready, device 0 (HD)
     int     BIOS_SYSTEM_INTERRUPT_15h
+.DoNotPostSinceIrqOccurredBeforeWait:
 
     pop     ax
-    pop     di
     iret
-
-
-;--------------------------------------------------------------------
-; AcknowledgeIdeInterruptAndSetTaskFlag
-;   Parameters:
-;       Nothing
-;   Returns:
-;       Nothing
-;   Corrupts registers:
-;       AX
-;--------------------------------------------------------------------
-ALIGN JUMP_ALIGN
-AcknowledgeIdeInterruptAndSetTaskFlag:
-    push    ds
-    push    si
-    push    dx
-    push    bx
-
-    ; Reading Status Register acknowledges IDE interrupt
-    call    RamVars_GetSegmentToDS
-    mov     bl, FLGH_DPT_INTERRUPT_IN_SERVICE
-    call    FindDPT_ToDSDIforFlagsHighInBL
-    INPUT_TO_AL_FROM_IDE_REGISTER STATUS_REGISTER_in
-
-    ; Clear Interrupt In-Service Flag from DPT
-    and     BYTE [di+DPT.bFlagsHigh], ~FLGH_DPT_INTERRUPT_IN_SERVICE
-
-    ; Set Task Flag
-    LOAD_BDA_SEGMENT_TO ds, ax
-    mov     BYTE [BDA.bHDTaskFlg], 0FFh     ; Set task flag
-
-    pop     bx
-    pop     dx
-    pop     si
-    pop     ds
-    ret