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/*
* cortex arm arch v7 cache flushing and invalidation
* included by l.s and rebootcode.s
*/
TEXT cacheiinv(SB), $-4 /* I invalidate */
MOVW $0, R0
MTCP CpSC, 0, R0, C(CpCACHE), C(CpCACHEinvi), CpCACHEall /* ok on cortex */
ISB
RET
/*
* set/way operators, passed a suitable set/way value in R0.
*/
TEXT cachedwb_sw(SB), $-4
MTCP CpSC, 0, R0, C(CpCACHE), C(CpCACHEwb), CpCACHEsi
RET
TEXT cachedwbinv_sw(SB), $-4
MTCP CpSC, 0, R0, C(CpCACHE), C(CpCACHEwbi), CpCACHEsi
RET
TEXT cachedinv_sw(SB), $-4
MTCP CpSC, 0, R0, C(CpCACHE), C(CpCACHEinvd), CpCACHEsi
RET
/* set cache size select */
TEXT setcachelvl(SB), $-4
MTCP CpSC, CpIDcssel, R0, C(CpID), C(CpIDidct), 0
ISB
RET
/* return cache sizes */
TEXT getwayssets(SB), $-4
MFCP CpSC, CpIDcsize, R0, C(CpID), C(CpIDidct), 0
RET
/*
* l1 cache operations.
* l1 and l2 ops are intended to be called from C, thus need save no
* caller's regs, only those we need to preserve across calls.
*/
TEXT cachedwb(SB), $-4
MOVW.W R14, -8(R13)
MOVW $cachedwb_sw(SB), R0
MOVW $1, R8
BL wholecache(SB)
MOVW.P 8(R13), R15
TEXT cachedwbinv(SB), $-4
MOVW.W R14, -8(R13)
MOVW $cachedwbinv_sw(SB), R0
MOVW $1, R8
BL wholecache(SB)
MOVW.P 8(R13), R15
TEXT cachedinv(SB), $-4
MOVW.W R14, -8(R13)
MOVW $cachedinv_sw(SB), R0
MOVW $1, R8
BL wholecache(SB)
MOVW.P 8(R13), R15
TEXT cacheuwbinv(SB), $-4
MOVM.DB.W [R14], (R13) /* save lr on stack */
MOVW CPSR, R1
CPSID /* splhi */
MOVM.DB.W [R1], (R13) /* save R1 on stack */
BL cachedwbinv(SB)
BL cacheiinv(SB)
MOVM.IA.W (R13), [R1] /* restore R1 (saved CPSR) */
MOVW R1, CPSR
MOVM.IA.W (R13), [R14] /* restore lr */
RET
/*
* architectural l2 cache operations
*/
TEXT _l2cacheuwb(SB), $-4
MOVW.W R14, -8(R13)
MOVW $cachedwb_sw(SB), R0
MOVW $2, R8
BL wholecache(SB)
MOVW.P 8(R13), R15 /* return */
TEXT _l2cacheuwbinv(SB), $-4
MOVW.W R14, -8(R13)
MOVW CPSR, R1
CPSID /* splhi */
MOVM.DB.W [R1], (R13) /* save R1 on stack */
MOVW $cachedwbinv_sw(SB), R0
MOVW $2, R8
BL wholecache(SB)
BL _l2cacheuinv(SB)
MOVM.IA.W (R13), [R1] /* restore R1 (saved CPSR) */
MOVW R1, CPSR
MOVW.P 8(R13), R15 /* return */
TEXT _l2cacheuinv(SB), $-4
MOVW.W R14, -8(R13)
MOVW $cachedinv_sw(SB), R0
MOVW $2, R8
BL wholecache(SB)
MOVW.P 8(R13), R15 /* return */
/*
* callers are assumed to be the above l1 and l2 ops.
* R0 is the function to call in the innermost loop.
* R8 is the cache level (1-origin: 1 or 2).
*
* R0 func to call at entry
* R1 func to call after entry
* R2 nsets
* R3 way shift (computed from R8)
* R4 set shift (computed from R8)
* R5 nways
* R6 set scratch
* R7 way scratch
* R8 cache level, 0-origin
* R9 extern reg up
* R10 extern reg m
*
* initial translation by 5c, then massaged by hand.
*/
TEXT wholecache+0(SB), $-4
MOVW CPSR, R2
MOVM.DB.W [R2,R14], (SP) /* save regs on stack */
MOVW R0, R1 /* save argument for inner loop in R1 */
SUB $1, R8 /* convert cache level to zero origin */
/* we might not have the MMU on yet, so map R1 (func) to R14's space */
MOVW R14, R0 /* get R14's segment ... */
AND $KSEGM, R0
BIC $KSEGM, R1 /* strip segment from func address */
ORR R0, R1 /* combine them */
/* get cache sizes */
SLL $1, R8, R0 /* R0 = (cache - 1) << 1 */
MTCP CpSC, CpIDcssel, R0, C(CpID), C(CpIDidct), 0 /* set cache select */
ISB
MFCP CpSC, CpIDcsize, R0, C(CpID), C(CpIDidct), 0 /* get cache sizes */
/* compute # of ways and sets for this cache level */
SRA $3, R0, R5 /* R5 (ways) = R0 >> 3 */
AND $((1<<10)-1), R5 /* R5 = (R0 >> 3) & MASK(10) */
ADD $1, R5 /* R5 (ways) = ((R0 >> 3) & MASK(10)) + 1 */
SRA $13, R0, R2 /* R2 = R0 >> 13 */
AND $((1<<15)-1), R2 /* R2 = (R0 >> 13) & MASK(15) */
ADD $1, R2 /* R2 (sets) = ((R0 >> 13) & MASK(15)) + 1 */
/* precompute set/way shifts for inner loop */
MOVW $(CACHECONF+0), R3 /* +0 = l1waysh */
MOVW $(CACHECONF+4), R4 /* +4 = l1setsh */
CMP $0, R8 /* cache == 1? */
ADD.NE $(4*2), R3 /* no, assume l2: +8 = l2waysh */
ADD.NE $(4*2), R3 /* +12 = l2setsh */
MOVW R14, R0 /* get R14's segment ... */
AND $KSEGM, R0
BIC $KSEGM, R3 /* strip segment from address */
ORR R0, R3 /* combine them */
BIC $KSEGM, R4 /* strip segment from address */
ORR R0, R4 /* combine them */
MOVW (R3), R3
MOVW (R4), R4
CMP $0, R3 /* sanity checks */
BEQ wbuggery
CMP $0, R4
BEQ sbuggery
CPSID /* splhi to make entire op atomic */
BARRIERS
/* iterate over ways */
MOVW $0, R7 /* R7: way */
outer:
/* iterate over sets */
MOVW $0, R6 /* R6: set */
inner:
/* compute set/way register contents */
SLL R3, R7, R0 /* R0 = way << R3 (L?WAYSH) */
ORR R8<<1, R0 /* R0 = way << L?WAYSH | (cache - 1) << 1 */
ORR R6<<R4, R0 /* R0 = way<<L?WAYSH | (cache-1)<<1 |set<<R4 */
BL (R1) /* call set/way operation with R0 arg. */
ADD $1, R6 /* set++ */
CMP R2, R6 /* set >= sets? */
BLT inner /* no, do next set */
ADD $1, R7 /* way++ */
CMP R5, R7 /* way >= ways? */
BLT outer /* no, do next way */
MOVM.IA.W (SP), [R2,R14] /* restore regs */
BARRIERS
MOVW R2, CPSR /* splx */
RET
wbuggery:
PUTC('?')
PUTC('c')
PUTC('w')
B topanic
sbuggery:
PUTC('?')
PUTC('c')
PUTC('s')
topanic:
MOVW $.string<>+0(SB), R0
BIC $KSEGM, R0 /* strip segment from address */
MOVW R14, R1 /* get R14's segment ... */
AND $KSEGM, R1
ORR R1, R0 /* combine them */
SUB $12, R13 /* not that it matters, since we're panicing */
MOVW R14, 8(R13)
BL panic(SB) /* panic("msg %#p", LR) */
bugloop:
WFI
B bugloop
DATA .string<>+0(SB)/8,$"bad cach"
DATA .string<>+8(SB)/8,$"e params"
DATA .string<>+16(SB)/8,$"\073 pc %\043p"
DATA .string<>+24(SB)/1,$"\z"
GLOBL .string<>+0(SB),$25
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