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#include "mem.h"
/*
* Entered here from Compaq's bootldr. First relocate to
* the location we're linked for and then copy back the
* decompressed kernel.
*
* All
*/
TEXT _start(SB), $-4
MOVW $setR12(SB), R12 /* load the SB */
MOVW $1, R0 /* dance to make 5l think that the magic */
MOVW $1, R1 /* numbers in WORDs below are being used */
CMP.S R0, R1 /* and to align them to where bootldr wants */
BEQ _start2
WORD $0x016f2818 /* magic number to say we are a kernel */
WORD $0xc0008000 /* entry point address */
WORD $0 /* size?, or end of data? */
_start2:
/* SVC mode, interrupts disabled */
MOVW $(PsrDirq|PsrDfiq|PsrMsvc), R1
MOVW R1, CPSR
/* disable the MMU */
MOVW $0x130, R1
MCR CpMMU, 0, R1, C(CpControl), C(0x0)
/* enable caches */
MRC CpMMU, 0, R0, C(CpControl), C(0x0)
ORR $(CpCdcache|CpCicache|CpCwb), R0
MCR CpMMU, 0, R0, C(CpControl), C(0x0)
/* flush caches */
MCR CpMMU, 0, R0, C(CpCacheFlush), C(0x7), 0
/* drain prefetch */
MOVW R0,R0
MOVW R0,R0
MOVW R0,R0
MOVW R0,R0
/* drain write buffer */
MCR CpMMU, 0, R0, C(CpCacheFlush), C(0xa), 4
/* relocate to where we expect to be */
MOVW $(512*1024),R3
MOVW $0xC0008000,R1
MOVW $0xC0200000,R2
ADD R1,R3
_relloop:
MOVW (R1),R0
MOVW R0,(R2)
ADD $4,R1
ADD $4,R2
CMP.S R1,R3
BNE _relloop
MOVW $(MACHADDR+BY2PG), R13 /* stack */
SUB $4, R13 /* link */
/* jump to where we've been relocated */
MOVW $_relocated(SB),R15
TEXT _relocated(SB),$-4
BL main(SB)
BL exit(SB)
/* we shouldn't get here */
_mainloop:
B _mainloop
BL _div(SB) /* hack to get _div etc loaded */
TEXT mypc(SB),$-4
MOVW R14,R0
RET
TEXT draincache(SB),$-4
/* write back any dirty data */
MOVW $0xe0000000,R0
ADD $(8*1024),R0,R1
_cfloop:
MOVW.P 32(R0),R2
CMP.S R0,R1
BNE _cfloop
/* drain write buffer and invalidate i&d cache contents */
MCR CpMMU, 0, R0, C(CpCacheFlush), C(0xa), 4
MCR CpMMU, 0, R0, C(CpCacheFlush), C(0x7), 0
/* drain prefetch */
MOVW R0,R0
MOVW R0,R0
MOVW R0,R0
MOVW R0,R0
/* disable caches */
MRC CpMMU, 0, R0, C(CpControl), C(0x0)
BIC $(CpCdcache|CpCicache|CpCwb), R0
MCR CpMMU, 0, R0, C(CpControl), C(0x0)
RET
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