40 lines
935 B
C
40 lines
935 B
C
/*
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* on return from this function we will be running in virtual mode.
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* We set up the Block Address Translation (BAT) registers thus:
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* 1) first 3 BATs are 256M blocks, starting from KZERO->0
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* 2) remaining BAT maps last 256M directly
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*/
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TEXT mmuinit0(SB), $0
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/* reset all the tlbs */
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MOVW $64, R3
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MOVW R3, CTR
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MOVW $0, R4
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tlbloop:
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TLBIE R4
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SYNC
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ADD $BIT(19), R4
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BDNZ tlbloop
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TLBSYNC
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/* BATs 0 and 1 cover memory from 0x00000000 to 0x20000000 */
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/* KZERO -> 0, IBAT2 and DBAT2, 256 MB */
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MOVW $(KZERO|(0x7ff<<2)|2), R3
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MOVW $(PTEVALID|PTEWRITE), R4 /* PTEVALID => Cache coherency on */
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MOVW R3, SPR(DBATU(2))
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MOVW R4, SPR(DBATL(2))
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MOVW R3, SPR(IBATU(2))
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MOVW R4, SPR(IBATL(2))
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/* enable MMU */
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MOVW LR, R3
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OR $KZERO, R3
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MOVW R3, SPR(SRR0) /* Stored PC for RFI instruction */
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MOVW MSR, R4
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OR $(MSR_IR|MSR_DR|MSR_RI|MSR_FP), R4
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MOVW R4, SPR(SRR1)
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RFI /* resume in kernel mode in caller */
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RETURN
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