ref: b0377e84cf31c48afed765c433abe7eebb4135a5
dir: /sys/src/9/omap/l.s/
/*
* ti omap3530 SoC machine assist
* arm cortex-a8 processor
*
* loader uses R11 as scratch.
* R9 and R10 are used for `extern register' variables.
*
* ARM v7 arch. ref. man. §B1.3.3 that we don't need barriers
* around moves to CPSR.
*/
#include "arm.s"
/*
* MCR and MRC are counter-intuitively named.
* MCR coproc, opcode1, Rd, CRn, CRm[, opcode2] # arm -> coproc
* MRC coproc, opcode1, Rd, CRn, CRm[, opcode2] # coproc -> arm
*/
/*
* Entered here from Das U-Boot or another Plan 9 kernel with MMU disabled.
* Until the MMU is enabled it is OK to call functions provided
* they are within ±32MiB relative and do not require any
* local variables or more than one argument (i.e. there is
* no stack).
*/
TEXT _start(SB), 1, $-4
MOVW $setR12(SB), R12 /* load the SB */
SUB $KZERO, R12
ADD $PHYSDRAM, R12
/* SVC mode, interrupts disabled */
MOVW $(PsrDirq|PsrDfiq|PsrMsvc), R1
MOVW R1, CPSR
BARRIERS
DELAY(printloopret, 1)
WAVE('\r')
DELAY(printloopnl, 1)
WAVE('\n')
/*
* work around errata
*/
MRC CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
ORR $(CpACissue1|CpACldstissue1), R1 /* fight omap35x errata 3.1.1.9 */
ORR $CpACibe, R1 /* enable cp15 invalidate */
ORR $CpACl1pe, R1 /* enable l1 parity checking */
ORR $CpCalign, R1 /* catch alignment errors */
BIC $CpACasa, R1 /* no speculative accesses */
/* go faster with fewer restrictions */
BIC $(CpACcachenopipe|CpACcp15serial|CpACcp15waitidle|CpACcp15pipeflush), R1
MCR CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
ISB
MRC CpSC, 1, R1, C(CpCLD), C(CpCLDl2), CpCLDl2aux
ORR $CpCl2nowralloc, R1 /* fight cortex errata 460075 */
ORR $(CpCl2ecc|CpCl2eccparity), R1
#ifdef TEDIUM
/*
* I don't know why this clobbers the system, but I'm tired
* of arguing with this fussy processor. To hell with it.
*/
MCR CpSC, 1, R1, C(CpCLD), C(CpCLDl2), CpCLDl2aux
ISB
#endif
DELAY(printloops, 1)
WAVE('P')
/*
* disable the MMU & caches
*/
MRC CpSC, 0, R1, C(CpCONTROL), C(0), CpMainctl
BIC $(CpCdcache|CpCicache|CpCmmu), R1
ORR $CpCsbo, R1
BIC $CpCsbz, R1
MCR CpSC, 0, R1, C(CpCONTROL), C(0), CpMainctl
ISB
MRC CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
BIC $CpACl2en, R1 /* turn l2 cache off */
MCR CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
ISB
WAVE('l')
DELAY(printloop3, 1)
WAVE('a')
/* clear Mach */
MOVW $PADDR(MACHADDR), R4 /* address of Mach */
MOVW $0, R0
_machZ:
MOVW R0, (R4)
ADD $4, R4
CMP.S $PADDR(L1+L1X(0)), R4 /* end at top-level page table */
BNE _machZ
/*
* set up the MMU page table
*/
WAVE('n')
/* clear all PTEs first, to provide a default */
// MOVW $PADDR(L1+L1X(0)), R4 /* address of PTE for 0 */
_ptenv0:
ZEROPTE()
CMP.S $PADDR(L1+16*KiB), R4
BNE _ptenv0
DELAY(printloop4, 2)
WAVE(' ')
/*
* set up double map of PHYSDRAM, KZERO to PHYSDRAM for first few MBs,
* but only if KZERO and PHYSDRAM differ.
*/
MOVW $PTEDRAM, R2 /* PTE bits */
MOVW $PHYSDRAM, R3 /* pa */
CMP $KZERO, R3
BEQ no2map
MOVW $PADDR(L1+L1X(PHYSDRAM)), R4 /* address of PTE for PHYSDRAM */
MOVW $DOUBLEMAPMBS, R5
_ptdbl:
FILLPTE()
SUB.S $1, R5
BNE _ptdbl
no2map:
/*
* back up and fill in PTEs for memory at KZERO.
* beagle has 1 bank of 256MB of SDRAM at PHYSDRAM;
* igepv2 has 1 bank of 512MB at PHYSDRAM.
* Map the maximum (512MB).
*/
WAVE('9')
MOVW $PTEDRAM, R2 /* PTE bits */
MOVW $PHYSDRAM, R3
MOVW $PADDR(L1+L1X(KZERO)), R4 /* start with PTE for KZERO */
MOVW $512, R5 /* inner loop count (MBs) */
_ptekrw: /* set PTEs */
FILLPTE()
SUB.S $1, R5 /* decrement inner loop count */
BNE _ptekrw
/*
* back up and fill in PTEs for MMIO
* stop somewhere after uarts
*/
WAVE(' ')
MOVW $PTEIO, R2 /* PTE bits */
MOVW $PHYSIO, R3
MOVW $PADDR(L1+L1X(VIRTIO)), R4 /* start with PTE for VIRTIO */
_ptenv2:
FILLPTE()
CMP.S $PADDR(L1+L1X(PHYSIOEND)), R4
BNE _ptenv2
/* mmu.c sets up the trap vectors later */
/*
* set up a temporary stack; avoid data & bss segments
*/
MOVW $(PHYSDRAM | (128*1024*1024)), R13
/* invalidate caches */
BL cachedinv(SB)
MOVW $KZERO, R0
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEinvi), CpCACHEall
ISB
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEwb), CpCACHEwait
BARRIERS
WAVE('f')
/*
* turn caches on
*/
MRC CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
ORR $CpACl2en, R1 /* turn l2 cache on */
MCR CpSC, 0, R1, C(CpCONTROL), C(0), CpAuxctl
BARRIERS
MRC CpSC, 0, R1, C(CpCONTROL), C(0), CpMainctl
ORR $(CpCdcache|CpCicache), R1
MCR CpSC, 0, R1, C(CpCONTROL), C(0), CpMainctl
BARRIERS
WAVE('r')
/* set the domain access control */
MOVW $Client, R0
BL dacput(SB)
DELAY(printloop5, 2)
WAVE('o')
/* set the translation table base */
MOVW $PADDR(L1), R0
BL ttbput(SB)
MOVW $0, R0
BL pidput(SB) /* paranoia */
WAVE('m')
/*
* the little dance to turn the MMU on
*/
BL cacheuwbinv(SB)
BL mmuinvalidate(SB)
BL mmuenable(SB)
WAVE(' ')
/* warp the PC into the virtual map */
MOVW $KZERO, R0
BL _r15warp(SB)
/*
* now running at KZERO+something!
*/
MOVW $setR12(SB), R12 /* reload the SB */
/*
* set up temporary stack again, in case we've just switched
* to a new register set.
*/
MOVW $(KZERO|(128*1024*1024)), R13
/* can now execute arbitrary C code */
BL cacheuwbinv(SB)
WAVE('B')
MOVW $PHYSDRAM, R3 /* pa */
CMP $KZERO, R3
BEQ no2unmap
/* undo double map of PHYSDRAM, KZERO & first few MBs */
MOVW $(L1+L1X(PHYSDRAM)), R4 /* addr. of PTE for PHYSDRAM */
MOVW $0, R0
MOVW $DOUBLEMAPMBS, R5
_ptudbl:
ZEROPTE()
SUB.S $1, R5
BNE _ptudbl
no2unmap:
BARRIERS
MOVW $KZERO, R0
MCR CpSC, 0, R0, C(CpTLB), C(CpTLBinvu), CpTLBinv
BARRIERS
#ifdef HIGH_SECURITY /* i.e., not GP omap */
/* hack: set `secure monitor' vector base addr for cortex */
// MOVW $HVECTORS, R0
MOVW $PADDR(L1), R0
SUB $(MACHSIZE+(2*1024)), R0
MCR CpSC, 0, R0, C(CpVECS), C(CpVECSbase), CpVECSmon
ISB
#endif
/*
* call main in C
* pass Mach to main and set up the stack in it
*/
MOVW $(MACHADDR), R0 /* Mach */
MOVW R0, R13
ADD $(MACHSIZE), R13 /* stack pointer */
SUB $4, R13 /* space for link register */
MOVW R0, R10 /* m = MACHADDR */
WAVE('e')
BL main(SB) /* void main(Mach*) */
/*FALLTHROUGH*/
/*
* reset the system
*/
TEXT _reset(SB), 1, $-4
MOVW $(PsrDirq|PsrDfiq|PsrMsvc), R0
MOVW R0, CPSR
BARRIERS
DELAY(printloopr, 2)
WAVE('!')
WAVE('r')
WAVE('e')
WAVE('s')
WAVE('e')
WAVE('t')
WAVE('!')
WAVE('\r')
WAVE('\n')
/* turn the caches off */
BL cacheuwbinv(SB)
MRC CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
BIC $(CpCicache|CpCdcache|CpCalign), R0
ORR $CpCsw, R0 /* enable SWP */
MCR CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
BARRIERS
/* redo double map of PHYSDRAM, KZERO & first few MBs */
MOVW $PTEDRAM, R2 /* PTE bits */
MOVW $PHYSDRAM, R3 /* pa */
MOVW $(L1+L1X(PHYSDRAM)), R4 /* address of PHYSDRAM's PTE */
MOVW $DOUBLEMAPMBS, R5
_ptrdbl:
FILLPTE()
SUB.S $1, R5
BNE _ptrdbl
MOVW $PHYSDRAM, R0
MCR CpSC, 0, R0, C(CpTLB), C(CpTLBinvu), CpTLBinv
BARRIERS
/* turn the MMU off */
MOVW $PHYSDRAM, R0
BL _r15warp(SB)
BL mmuinvalidate(SB)
BL mmudisable(SB)
/* set new reset vector */
MOVW $HVECTORS, R2
MOVW $0xe59ff018, R3 /* MOVW 0x18(R15), R15 */
MOVW R3, (R2)
BARRIERS
// MOVW $PHYSFLASH, R3 /* TODO */
// MOVW R3, 0x20(R2) /* where $0xe59ff018 jumps to */
/* ...and jump to it */
// MOVW R2, R15 /* software reboot */
_limbo: /* should not get here... */
BL idlehands(SB)
B _limbo /* ... and can't get out */
BL _div(SB) /* hack to load _div, etc. */
TEXT _r15warp(SB), 1, $-4
BIC $KSEGM, R14 /* link reg, will become PC */
ORR R0, R14
BIC $KSEGM, R13 /* SP too */
ORR R0, R13
RET
/*
* `single-element' cache operations.
* in arm arch v7, they operate on all cache levels, so separate
* l2 functions are unnecessary.
*/
TEXT cachedwbse(SB), $-4 /* D writeback SE */
MOVW R0, R2
MOVW CPSR, R3
CPSID /* splhi */
BARRIERS /* force outstanding stores to cache */
MOVW R2, R0
MOVW 4(FP), R1
ADD R0, R1 /* R1 is end address */
BIC $(CACHELINESZ-1), R0 /* cache line start */
_dwbse:
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEwb), CpCACHEse
/* can't have a BARRIER here since it zeroes R0 */
ADD $CACHELINESZ, R0
CMP.S R0, R1
BGT _dwbse
B _wait
TEXT cachedwbinvse(SB), $-4 /* D writeback+invalidate SE */
MOVW R0, R2
MOVW CPSR, R3
CPSID /* splhi */
BARRIERS /* force outstanding stores to cache */
MOVW R2, R0
MOVW 4(FP), R1
ADD R0, R1 /* R1 is end address */
BIC $(CACHELINESZ-1), R0 /* cache line start */
_dwbinvse:
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEwbi), CpCACHEse
/* can't have a BARRIER here since it zeroes R0 */
ADD $CACHELINESZ, R0
CMP.S R0, R1
BGT _dwbinvse
_wait: /* drain write buffer */
BARRIERS
/* drain L1 write buffer, also drains L2 eviction buffer on sheeva */
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEwb), CpCACHEwait
ISB
MOVW R3, CPSR /* splx */
RET
TEXT cachedinvse(SB), $-4 /* D invalidate SE */
MOVW R0, R2
MOVW CPSR, R3
CPSID /* splhi */
BARRIERS /* force outstanding stores to cache */
MOVW R2, R0
MOVW 4(FP), R1
ADD R0, R1 /* R1 is end address */
BIC $(CACHELINESZ-1), R0 /* cache line start */
_dinvse:
MCR CpSC, 0, R0, C(CpCACHE), C(CpCACHEinvd), CpCACHEse
/* can't have a BARRIER here since it zeroes R0 */
ADD $CACHELINESZ, R0
CMP.S R0, R1
BGT _dinvse
B _wait
/*
* enable mmu and high vectors
*/
TEXT mmuenable(SB), 1, $-4
MRC CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
ORR $(CpChv|CpCmmu), R0
MCR CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
BARRIERS
RET
TEXT mmudisable(SB), 1, $-4
MRC CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
BIC $(CpChv|CpCmmu), R0
MCR CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
BARRIERS
RET
/*
* If one of these MCR instructions crashes or hangs the machine,
* check your Level 1 page table (at TTB) closely.
*/
TEXT mmuinvalidate(SB), $-4 /* invalidate all */
MOVW CPSR, R2
CPSID /* interrupts off */
BARRIERS
MOVW PC, R0 /* some valid virtual address */
MCR CpSC, 0, R0, C(CpTLB), C(CpTLBinvu), CpTLBinv
BARRIERS
MOVW R2, CPSR /* interrupts restored */
RET
TEXT mmuinvalidateaddr(SB), $-4 /* invalidate single entry */
MCR CpSC, 0, R0, C(CpTLB), C(CpTLBinvu), CpTLBinvse
BARRIERS
RET
TEXT cpidget(SB), 1, $-4 /* main ID */
MRC CpSC, 0, R0, C(CpID), C(0), CpIDid
RET
TEXT cpctget(SB), 1, $-4 /* cache type */
MRC CpSC, 0, R0, C(CpID), C(0), CpIDct
RET
TEXT controlget(SB), 1, $-4 /* control */
MRC CpSC, 0, R0, C(CpCONTROL), C(0), CpMainctl
RET
TEXT ttbget(SB), 1, $-4 /* translation table base */
MRC CpSC, 0, R0, C(CpTTB), C(0), CpTTB0
RET
TEXT ttbput(SB), 1, $-4 /* translation table base */
MCR CpSC, 0, R0, C(CpTTB), C(0), CpTTB0
MCR CpSC, 0, R0, C(CpTTB), C(0), CpTTB1 /* cortex has two */
ISB
RET
TEXT dacget(SB), 1, $-4 /* domain access control */
MRC CpSC, 0, R0, C(CpDAC), C(0)
RET
TEXT dacput(SB), 1, $-4 /* domain access control */
MCR CpSC, 0, R0, C(CpDAC), C(0)
ISB
RET
TEXT fsrget(SB), 1, $-4 /* data fault status */
MRC CpSC, 0, R0, C(CpFSR), C(0), CpDFSR
RET
TEXT ifsrget(SB), 1, $-4 /* instruction fault status */
MRC CpSC, 0, R0, C(CpFSR), C(0), CpIFSR
RET
TEXT farget(SB), 1, $-4 /* fault address */
MRC CpSC, 0, R0, C(CpFAR), C(0x0)
RET
TEXT getpsr(SB), 1, $-4
MOVW CPSR, R0
RET
TEXT getscr(SB), 1, $-4
MRC CpSC, 0, R0, C(CpCONTROL), C(CpCONTROLscr), CpSCRscr
RET
TEXT pidget(SB), 1, $-4 /* address translation pid */
MRC CpSC, 0, R0, C(CpPID), C(0x0)
RET
TEXT pidput(SB), 1, $-4 /* address translation pid */
MCR CpSC, 0, R0, C(CpPID), C(0x0)
ISB
RET
TEXT splhi(SB), 1, $-4
MOVW CPSR, R0
CPSID /* turn off interrupts */
MOVW $(MACHADDR+4), R2 /* save caller pc in Mach */
MOVW R14, 0(R2)
RET
TEXT spllo(SB), 1, $-4 /* start marker for devkprof.c */
MOVW CPSR, R0
CPSIE
RET
TEXT splx(SB), 1, $-4
MOVW $(MACHADDR+0x04), R2 /* save caller pc in Mach */
MOVW R14, 0(R2)
MOVW CPSR, R3
MOVW R0, CPSR /* reset interrupt level */
MOVW R3, R0 /* must return old CPSR */
RET
TEXT spldone(SB), 1, $0 /* end marker for devkprof.c */
RET
TEXT islo(SB), 1, $-4
MOVW CPSR, R0
AND $(PsrDirq), R0
EOR $(PsrDirq), R0
RET
TEXT tas(SB), $-4
TEXT _tas(SB), $-4
MOVW R0,R1
MOVW $1,R0
SWPW R0,(R1) /* fix: deprecated in armv7 */
RET
TEXT clz(SB), $-4
CLZ(0, 0) /* 0 is R0 */
RET
TEXT setlabel(SB), 1, $-4
MOVW R13, 0(R0) /* sp */
MOVW R14, 4(R0) /* pc */
MOVW $0, R0
RET
TEXT gotolabel(SB), 1, $-4
MOVW 0(R0), R13 /* sp */
MOVW 4(R0), R14 /* pc */
MOVW $1, R0
RET
TEXT getcallerpc(SB), 1, $-4
MOVW 0(R13), R0
RET
TEXT idlehands(SB), $-4
BARRIERS
WFI
RET
TEXT coherence(SB), $-4
BARRIERS
RET
#include "cache.v7.s"