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Diffstat (limited to 'board/MAI/bios_emulator/scitech/src/pm/ntdrv/_irq.asm')
| -rw-r--r-- | board/MAI/bios_emulator/scitech/src/pm/ntdrv/_irq.asm | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/board/MAI/bios_emulator/scitech/src/pm/ntdrv/_irq.asm b/board/MAI/bios_emulator/scitech/src/pm/ntdrv/_irq.asm new file mode 100644 index 0000000000..11824a0afc --- /dev/null +++ b/board/MAI/bios_emulator/scitech/src/pm/ntdrv/_irq.asm @@ -0,0 +1,288 @@ +;**************************************************************************** +;* +;* SciTech OS Portability Manager Library +;* +;* ======================================================================== +;* +;* The contents of this file are subject to the SciTech MGL Public +;* License Version 1.0 (the "License"); you may not use this file +;* except in compliance with the License. You may obtain a copy of +;* the License at http://www.scitechsoft.com/mgl-license.txt +;* +;* Software distributed under the License is distributed on an +;* "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or +;* implied. See the License for the specific language governing +;* rights and limitations under the License. +;* +;* The Original Code is Copyright (C) 1991-1998 SciTech Software, Inc. +;* +;* The Initial Developer of the Original Code is SciTech Software, Inc. +;* All Rights Reserved. +;* +;* ======================================================================== +;* +;* Language: 80386 Assembler, TASM 4.0 or NASM +;* Environment: 32-bit Windows NT device driver +;* +;* Description: Low level assembly support for the PM library specific to +;* Windows NT device drivers. +;* +;**************************************************************************** + + IDEAL + +include "scitech.mac" ; Memory model macros + +header _irq ; Set up memory model + +begdataseg _irq + + cextern _PM_rtcHandler,CPTR + cextern _PM_prevRTC,FCPTR + +RtcInside dw 0 ; Are we still handling current interrupt +sidtBuf df 0 ; Buffer for sidt instruction + +enddataseg _irq + +begcodeseg _irq ; Start of code segment + +cpublic _PM_irqCodeStart + +; Macro to delay briefly to ensure that enough time has elapsed between +; successive I/O accesses so that the device being accessed can respond +; to both accesses even on a very fast PC. + +ifdef USE_NASM +%macro DELAY 0 + jmp short $+2 + jmp short $+2 + jmp short $+2 +%endmacro +%macro IODELAYN 1 +%rep %1 + DELAY +%endrep +%endmacro +else +macro DELAY + jmp short $+2 + jmp short $+2 + jmp short $+2 +endm +macro IODELAYN N + rept N + DELAY + endm +endm +endif + +;---------------------------------------------------------------------------- +; PM_rtcISR - Real time clock interrupt subroutine dispatcher +;---------------------------------------------------------------------------- +; Hardware interrupt handler for the timer interrupt, to dispatch control +; to high level C based subroutines. We save the state of all registers +; in this routine, and switch to a local stack. Interrupts are *off* +; when we call the user code. +; +; NOTE: This routine switches to a local stack before calling any C code, +; and hence is _not_ re-entrant. Make sure your C code executes as +; quickly as possible, since a timer overrun will simply hang the +; system. +;---------------------------------------------------------------------------- +cprocfar _PM_rtcISR + +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +; If we enable interrupts and call into any C based interrupt handling code, +; we need to setup a bunch of important information for the NT kernel. The +; code below takes care of this housekeeping for us (see Undocumented NT for +; details). If we don't do this housekeeping and interrupts are enabled, +; the kernel will become very unstable and crash within 10 seconds or so. +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + + pushad + pushfd + push fs + + mov ebx,00000030h + mov fs,bx + sub esp,50h + mov ebp,esp + +; Setup the exception frame to NULL + + mov ebx,[DWORD cs:0FFDFF000h] + mov [DWORD ds:0FFDFF000h], 0FFFFFFFFh + mov [DWORD ebp],ebx + +; Save away the existing KSS ebp + + mov esi,[DWORD cs:0FFDFF124h] + mov ebx,[DWORD esi+00000128h] + mov [DWORD ebp+4h],ebx + mov [DWORD esi+00000128h],ebp + +; Save away the kernel time and the thread mode (kernel/user) + + mov edi,[DWORD esi+00000137h] + mov [DWORD ebp+8h],edi + +; Set the thread mode (kernel/user) based on the code selector + + mov ebx,[DWORD ebp+7Ch] + and ebx,01 + mov [BYTE esi+00000137h],bl + +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +; End of special interrupt Prolog code +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + +; Clear priority interrupt controller and re-enable interrupts so we +; dont lock things up for long. + + mov al,20h + out 0A0h,al + out 020h,al + +; Clear real-time clock timeout + + in al,70h ; Read CMOS index register + push eax ; and save for later + IODELAYN 3 + mov al,0Ch + out 70h,al + IODELAYN 5 + in al,71h + +; Call the C interrupt handler function + + cmp [BYTE RtcInside],1 ; Check for mutual exclusion + je @@Exit + mov [BYTE RtcInside],1 + sti ; Enable interrupts + cld ; Clear direction flag for C code + call [CPTR _PM_rtcHandler] + cli ; Disable interrupts on exit! + mov [BYTE RtcInside],0 + +@@Exit: pop eax + out 70h,al ; Restore CMOS index register + +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +; Start of special epilog code to restore stuff on exit from handler +;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + +; Restore the KSS ebp + + mov esi,[DWORD cs:0FFDFF124h] + mov ebx,[DWORD ebp+4] + mov [DWORD esi+00000128h],ebx + +; Restore the exception frame + + mov ebx,[DWORD ebp] + mov [DWORD fs:00000000],ebx + +; Restore the thread mode + + mov ebx,[DWORD ebp+8h] + mov esi,[DWORD fs:00000124h] + mov [BYTE esi+00000137h],bl + add esp, 50h + pop fs + popfd + popad + +; Return from interrupt + + iret + +cprocend + +cpublic _PM_irqCodeEnd + +;---------------------------------------------------------------------------- +; void _PM_getISR(int irq,PMFARPTR *handler); +;---------------------------------------------------------------------------- +; Function to return the specific IRQ handler direct from the IDT. +;---------------------------------------------------------------------------- +cprocstart _PM_getISR + + ARG idtEntry:UINT, handler:DPTR + + enter_c 0 + mov ecx,[handler] ; Get address of handler to fill in + sidt [sidtBuf] ; Get IDTR register into sidtBuf + mov eax,[DWORD sidtBuf+2] ; Get address of IDT into EAX + mov ebx,[idtEntry] + lea eax,[eax+ebx*8] ; Get entry in the IDT + movzx edx,[WORD eax+6] ; Get high order 16-bits + shl edx,16 ; Move into top 16-bits of address + mov dx,[WORD eax] ; Get low order 16-bits + mov [DWORD ecx],edx ; Store linear address of handler + mov dx,[WORD eax+2] ; Get selector value + mov [WORD ecx+4],dx ; Store selector value + leave_c + ret + +cprocend _PM_getISR + +;---------------------------------------------------------------------------- +; void _PM_setISR(int irq,void *handler); +;---------------------------------------------------------------------------- +; Function to set the specific IRQ handler direct in the IDT. +;---------------------------------------------------------------------------- +cprocstart _PM_setISR + + ARG irq:UINT, handler:CPTR + + enter_c 0 + mov ecx,[handler] ; Get address of new handler + mov dx,cs ; Get selector for new handler + sidt [sidtBuf] ; Get IDTR register into sidtBuf + mov eax,[DWORD sidtBuf+2] ; Get address of IDT into EAX + mov ebx,[idtEntry] + lea eax,[eax+ebx*8] ; Get entry in the IDT + cli + mov [WORD eax+2],dx ; Store code segment selector + mov [WORD eax],cx ; Store low order bits of handler + shr ecx,16 + mov [WORD eax+6],cx ; Store high order bits of handler + sti + leave_c + ret + +cprocend _PM_setISR + +;---------------------------------------------------------------------------- +; void _PM_restoreISR(int irq,PMFARPTR *handler); +;---------------------------------------------------------------------------- +; Function to set the specific IRQ handler direct in the IDT. +;---------------------------------------------------------------------------- +cprocstart _PM_restoreISR + + ARG irq:UINT, handler:CPTR + + enter_c 0 + mov ecx,[handler] + mov dx,[WORD ecx+4] ; Get selector for old handler + mov ecx,[DWORD ecx] ; Get address of old handler + sidt [sidtBuf] ; Get IDTR register into sidtBuf + mov eax,[DWORD sidtBuf+2] ; Get address of IDT into EAX + mov ebx,[idtEntry] + lea eax,[eax+ebx*8] ; Get entry in the IDT + cli + mov [WORD eax+2],dx ; Store code segment selector + mov [WORD eax],cx ; Store low order bits of handler + shr ecx,16 + mov [WORD eax+6],cx ; Store high order bits of handler + sti + leave_c + ret + +cprocend _PM_restoreISR + +endcodeseg _irq + + END ; End of module + |
