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Markus Fröschle
2013-08-02 22:14:59 +00:00
parent 375131230b
commit 2090f21359
1 changed files with 15 additions and 15 deletions
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30
sources/exceptions.S
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@@ -440,25 +440,25 @@ acess:
move.w #0x2700,sr // disable interrupt move.w #0x2700,sr // disable interrupt
move.l d0,-(sp) // ++ vr move.l d0,-(sp) // ++ vr
move.w 4(sp),d0 move.w 4(sp),d0
andi.l #0x0c03,d0 andi.l #0x0c03,d0 // mask out fault status bits
cmpi.l #0x0401,d0 cmpi.l #0x0401,d0 // TLB miss on opword of instruction fetch?
beq access_mmu beq access_mmu // yes
cmpi.l #0x0402,d0 cmpi.l #0x0402,d0 // TLB miss on extension word of instruction fetch?
beq access_mmu beq access_mmu // yes
cmpi.l #0x0802,d0 cmpi.l #0x0802,d0 // TLB miss on data write?
beq access_mmu beq access_mmu // yes
cmpi.l #0x0c02,d0 cmpi.l #0x0c02,d0 // TLB miss on data read, or read-modify-write?
beq access_mmu beq access_mmu // yes
bra bus_error bra bus_error // everything else
access_mmu: access_mmu:
move.l MCF_MMU_MMUSR,d0 move.l MCF_MMU_MMUSR,d0 // did the last fault hit in TLB?
btst #1,d0 btst #1,d0 // no
bne bus_error bne bus_error // bus error handler
move.l MCF_MMU_MMUAR,d0 move.l MCF_MMU_MMUAR,d0
cmp.l #__FASTRAM_END,d0 // max User RAM Bereich cmp.l #__FASTRAM_END,d0 // above max User RAM area?
bge bus_error // -> bus error bge bus_error // -> bus error
bra _mmutr_miss bra _mmutr_miss // else we have an MMU TLB miss
bus_error: bus_error:
move.l (sp)+,d0 // restore register move.l (sp)+,d0 // restore register