;************************************************************************* ;** mmu.library ** ;** ** ;** a system library for arbitration and control of the MC68K MMUs ** ;** ** ;** © 1998 THOR-Software, Thomas Richter ** ;** No commercial use, reassembly, modification without prior, written ** ;** permission of the authors. ** ;** Including this library in any commercial software REQUIRES a ** ;** written permission and the payment of a small fee. ** ;** ** ;** This is an internal header file, do not depend on anything here. ** ;** Use the official include files. ** ;** Distributed only for the mmu.library development group for private ** ;** use. ** ;** ** ;**---------------------------------------------------------------------** ;** Block: Detect.a ** ;** Detect a possible MMU, return the type in d0 ** ;** Version 0.01 15.09.1998 © THOR ** ;************************************************************************* ;FOLD Includes include INC:exec_lib.asm include mu_lib.i ;ENDFOLD ;FOLD Externals xref SubSuper ;ENDFOLD section main_code,code ;FOLD DetectMMUType ;************************************************* ;** DetectMMUType ** ;** Return the type of the MMU installed ** ;** this does NOT YET check whether an EC type ** ;** processor is installed, this must be done ** ;** manually afterwards. It checks only the ** ;** possible type of the MMU ** ;************************************************* xdef DetectMMUType DetectMMUType: move.b mulib_AttnFlags(a6),d1 ;get CPU type btst #AF_68060,d1 bne.s .found060 tst.l mulib_060Base(a6) bne.s .found060 btst #AF_68040,d1 bne.s .found040 moveq #mutype_none,d0 btst #AF_68020,d1 ;not even a '020? beq.s .found ;if so, exit ;check here whether MMU is available pea Check020MMU(pc) bsr SubSuper ;run this tst.l d0 ;what is it? beq.s .found ;nothing ? moveq #mutype_68030,d0 btst #AF_68030,mulib_AttnFlags(a6) ;is the '030 installed ? bne.s .found moveq #mutype_68851,d0 bra.s .found .found060: bset #AF_68060,mulib_AttnFlags(a6) pea Check060MMU(pc) bsr SubSuper tst.l d0 beq.s .found moveq #mutype_68060,d0 bra.s .found .found040: bset #AF_68040,mulib_AttnFlags(a6) pea Check040MMU(pc) bsr SubSuper tst.l d0 beq.s .found moveq #mutype_68040,d0 .found: rts ;ENDFOLD ;FOLD Check020MMU ;************************************************* ;** Check020MMU ** ;** Check, whether a 68851 is on board ** ;************************************************* machine mc68020 pmmu Check020MMU: ori.w #$0700,sr ;disable interrupts lea -$e4(a7),a7 ;reserve room for termporary ;exception vectors movec.l vbr,a0 ;saveback VBR lea .illegal(pc),a1 ;entry for Illegal/LineF move.l a1,$10(a7) ;set it move.l a1,$2c(a7) ;ditto lea .nmi(pc),a1 move.l a1,$7c(a7) ;NMI disable lea .config(pc),a1 move.l a1,$e0(a7) movec.l a7,vbr ;VBR temporary on stack clr.l 4(a7) ;clear this moveq #1,d0 ;default result is: YES pmove tc,(a7) ;try to read translation control pmove 4(a7),tc ;try to write it tst.l (a7) ;Enabled ? bpl.s .continue ;continue if disabled pmove (a7),tc ;is enabled. If so, must be valid .continue: movec.l a0,vbr ;restore VBR ;result is in d0 lea $e4(a7),a7 ;release stack .nmi: rte ;this restores interrupts anyways .illegal: moveq #0,d0 addq.l #8,a7 ;remove exception stack frame bra.s .continue .config: moveq #0,d0 addq.l #8,a7 addq.l #4,a7 bra.s .continue ;MMU configuration error ;ENDFOLD ;FOLD Check040MMU ;************************************************* ;** Check040MMU ** ;** Check, whether a 68040 MMU is on board ** ;************************************************* machine mc68040 Check040MMU: ori.w #$0700,sr ;disable interrupts lea -$80(a7),a7 ;reserve room for termporary ;exception vectors movec.l vbr,a0 ;saveback VBR lea .illegal(pc),a1 ;entry for Illegal/LineF move.l a1,$10(a7) ;set it move.l a1,$2c(a7) ;ditto lea .nmi(pc),a1 move.l a1,$7c(a7) ;NMI disable movec.l a7,vbr ;VBR temporary on stack moveq #1,d0 ;default result is: YES moveq #0,d1 sub.l a1,a1 movec.l tc,d1 ;try to read translation control movec.l a1,tc ;try to clear it tst.w d1 ;enabled ? bpl.s .continue movec.l d1,tc ;if enabled, write back .continue: movec.l a0,vbr ;restore VBR ;result is in d0 lea $80(a7),a7 ;release stack .nmi: rte ;this restores interrupts anyways .illegal: moveq #0,d0 addq.l #8,a7 ;remove exception stack frame bra.s .continue ;ENDFOLD ;FOLD Check060MMU ;************************************************* ;** Check060MMU ** ;** Check, whether a 68060 MMU is on board ** ;************************************************* machine mc68060 Check060MMU: ori.w #$0700,sr ;disable interrupts lea -$80(a7),a7 ;reserve room for termporary ;exception vectors movec.l vbr,a0 ;saveback VBR lea .illegal(pc),a1 ;entry for Illegal/LineF move.l a1,$10(a7) ;set it move.l a1,$2c(a7) ;ditto lea .nmi(pc),a1 move.l a1,$7c(a7) ;NMI disable movec.l a7,vbr ;VBR temporary on stack moveq #0,d0 movec.l pcr,d1 swap d1 cmp.w #%0000010000110000,d1 bne.s .continue moveq #1,d0 ;default result is: YES moveq #0,d1 sub.l a1,a1 movec.l tc,d1 ;try to read translation control movec.l a1,tc ;try to clear it tst.w d1 ;enabled ? bpl.s .continue movec.l d1,tc ;if enabled, write back .continue: movec.l a0,vbr ;restore VBR ;result is in d0 lea $80(a7),a7 ;release stack .nmi: rte ;this restores interrupts anyways .illegal: moveq #0,d0 addq.l #8,a7 ;remove exception stack frame bra.s .continue ;ENDFOLD ;FOLD ReadVBR ;************************************************* ;** ReadVBR ** ;** read the vector base register -> a0 ** ;** this is not necessarely fast, but executes ** ;** fine in user mode ** ;************************************************* machine mc68010 xdef ReadVBR ReadVBR: sub.l a0,a0 btst #AF_68010,mulib_AttnFlags(a6) ;only 68010 and up beq.s .exit pea _ReadVBR(pc) bsr SubSuper .exit: rts _ReadVBR: movec.l vbr,a0 rte ;ENDFOLD