Mercurial > hg > Members > kono > nitros9-code
changeset 2012:775551ca320f
Added comments
| author | boisy |
|---|---|
| date | Mon, 06 Mar 2006 04:09:19 +0000 |
| parents | 484c5493599a |
| children | 55210a27019c |
| files | level1/modules/kernel/krn.asm |
| diffstat | 1 files changed, 50 insertions(+), 60 deletions(-) [+] |
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--- a/level1/modules/kernel/krn.asm Mon Mar 06 04:08:59 2006 +0000 +++ b/level1/modules/kernel/krn.asm Mon Mar 06 04:09:19 2006 +0000 @@ -15,6 +15,8 @@ * | Free Memory Bitmap | * $0200-$021F | (1 bit = 256 byte page) | * |----------------------------------| +* $0220-$0221 | IOMan I/O Call Pointer | +* |----------------------------------| * | System Dispatch Table | * $0222-$0291 | (Room for 56 addresses) | * |----------------------------------| @@ -65,7 +67,7 @@ rev set $01 edition set 15 -L0000 mod eom,name,tylg,atrv,OS9Cold,size +ModTop mod eom,name,tylg,atrv,OS9Cold,size size equ . @@ -99,52 +101,36 @@ SysTbl fcb F$Link fdb FLink-*-2 - fcb F$Fork fdb FFork-*-2 - fcb F$Chain fdb FChain-*-2 - fcb F$Chain+$80 fdb SFChain-*-2 - fcb F$PrsNam fdb FPrsNam-*-2 - fcb F$CmpNam fdb FCmpNam-*-2 - fcb F$SchBit fdb FSchBit-*-2 - fcb F$AllBit fdb FAllBit-*-2 - fcb F$DelBit fdb FDelBit-*-2 - fcb F$CRC fdb FCRC-*-2 - fcb F$SRqMem+$80 fdb FSRqMem-*-2 - fcb F$SRtMem+$80 fdb FSRtMem-*-2 - fcb F$AProc+$80 fdb FAProc-*-2 - fcb F$NProc+$80 fdb FNProc-*-2 - fcb F$VModul+$80 fdb FVModul-*-2 - fcb F$SSvc fdb FSSvc-*-2 - fcb $80 IFNE H6309 @@ -242,13 +228,13 @@ bcs L00DB * Copy vectors to system globals L00EE leay >Vectors,pcr - leax >L0000,pcr + leax >ModTop,pcr pshs x ldx #D.SWI3 L00FB ldd ,y++ addd ,s std ,x++ - cmpx #$0036 + cmpx #D.NMI bls L00FB leas 2,s restore stack @@ -300,12 +286,13 @@ negb lbsr L065A -* jump into OS9p2 here +* jump into krnp2 here leax >P2Nam,pcr lda #Systm+Objct os9 F$Link lbcs OS9Cold jmp ,y + SWI3 pshs pc,x,b ldb #P$SWI3 bra L018C @@ -325,17 +312,17 @@ * transition from user to system state URtoSs clra tfr a,dp clear direct page - ldx <D.Proc - ldd <D.SysSvc - std <D.SWI2 - ldd <D.SysIRQ - std <D.SvcIRQ - leau ,s - stu P$SP,x - lda P$State,x - ora #SysState - sta P$State,x - jmp ,y + ldx <D.Proc get current process desc + ldd <D.SysSvc get system state system call vector + std <D.SWI2 store in D.SWI2 + ldd <D.SysIRQ get system IRQ vector + std <D.SvcIRQ store in D.SvcIRQ + leau ,s point U to S + stu P$SP,x and save in process P$SP + lda P$State,x get state field in proc desc + ora #SysState mark process to be in system state + sta P$State,x store it + jmp ,y jump to ,y L01B1 jsr [>D.Poll] bcc L01BD @@ -468,44 +455,48 @@ puls pc,u,y restore U/Y and return +* User-State system call entry point UsrSvc leay <L024E,pcr orcc #IntMasks lbra URtoSs L024E andcc #^IntMasks ldy <D.UsrDis - bsr L0278 + bsr DoSysCall L0255 ldx <D.Proc get current proc desc beq FNProc branch to FNProc if none - orcc #IntMasks - ldb P$State,x - andb #^SysState - stb P$State,x - bitb #TimOut - beq L02D1 - andb #^TimOut - stb P$State,x + orcc #IntMasks mask interrupts + ldb P$State,x get state value in proc desc + andb #^SysState turn off system state flag + stb P$State,x save state value + bitb #TimOut timeout bit set? + beq L02D1 branch if not + andb #^TimOut else turn off bit + stb P$State,x in state value bsr L021A bra FNProc -* system call entry +* System-State system call entry point SysSvc clra tfr a,dp set direct page to 0 - leau ,s - ldy <D.SysDis - bsr L0278 + leau ,s point U to SP + ldy <D.SysDis get system state dispatch table ptr + bsr DoSysCall rti -L0278 pshs u +* Entry: Y = Dispatch table (user or system) +DoSysCall + pshs u ldx R$PC,u point X to PC ldb ,x+ get func code at X stx R$PC,u restore updated PC - lslb multiply by 2 - bcc L0288 branch if user call - rorb - ldx -2,y + lslb high bit set? + bcc L0288 branch if not (non I/O call) + rorb else restore B (its an I/O call) + ldx -2,y grab IOMan vector +* Note: should check if X is zero in case IOMan was not installed. bra L0290 -L0288 cmpb #$6E +L0288 cmpb #$37*2 bcc L02A7 ldx b,y X = addr of system call beq L02A7 @@ -1185,13 +1176,13 @@ *L07C9 andcc #^Carry * rts -FSSvc ldy R$Y,u - bra InstSSvc +FSSvc ldy R$Y,u get caller's Y + bra InstSSvc install the service SSvcLoop tfr b,a put syscall code in A anda #$7F kill hi bit cmpa #$7F is code $7F? beq SSvcOK - cmpa #$37 compare against highest call allowed + cmpa #$37 compare against highest call allowed bcs SSvcOK branch if A less than highest call comb ldb #E$ISWI @@ -1213,12 +1204,11 @@ eom equ * fdb Clock -Vectors fdb SWI3 SWI3 - fdb SWI2 SWI2 - fdb DUMMY FIRQ - fdb SVCIRQ IRQ - fdb SWI SWI - fdb DUMMY NMI +Vectors fdb SWI3 SWI3 + fdb SWI2 SWI2 + fdb DUMMY FIRQ + fdb SVCIRQ IRQ + fdb SWI SWI + fdb DUMMY NMI end -