ref: a5db044fd3ccb8f021d4deb07b3dc732ed41d699
dir: /sys/src/9/mt7688/l.s/
/*
* mips 24k machine assist for mt7688
*/
#include "mem.h"
#include "mips24k.s"
#define SANITY 0x12345678
NOSCHED
/*
* Boot only processor
*/
TEXT start(SB), $-4
MOVW $setR30(SB), R30
DI(0)
MOVW sanity(SB), R1
CONST(SANITY, R2)
SUBU R1, R2, R2
BNE R2, insane
NOP
MOVW R0, M(COMPARE)
EHB
/* don't enable any interrupts nor FP, but leave BEV on. */
MOVW $BEV,R1
MOVW R1, M(STATUS)
UBARRIERS(7, R7, stshb) /* returns to kseg1 space */
MOVW R0, M(CAUSE)
EHB
/* disable watchdog and other resets */
MOVW $(KSEG1|0x10000038), R1
MOVW R0, (R1) /* set no action */
SYNC
MOVW $PE, R1
MOVW R1, M(CACHEECC) /* aka ErrCtl */
EHB
JAL cleancache(SB)
NOOP
MOVW $TLBROFF, R1
MOVW R1, M(WIRED)
MOVW R0, M(CONTEXT)
EHB
/* set KSEG0 cachability before trying LL/SC in lock code */
MOVW M(CONFIG), R1
AND $~CFG_K0, R1
/* make kseg0 cachable, enable write-through merging */
OR $((PTECACHED>>3)|CFG_MM), R1
MOVW R1, M(CONFIG)
BARRIERS(7, R7, cfghb) /* back to kseg0 space */
MOVW $setR30(SB), R30 /* again */
/* initialize Mach, including stack */
MOVW $MACHADDR, R(MACH)
ADDU $(MACHSIZE-BY2V), R(MACH), SP
MOVW R(MACH), R1
clrmach:
MOVW R0, (R1)
ADDU $BY2WD, R1
BNE R1, SP, clrmach
NOOP
MOVW $edata(SB), R1
MOVW $end(SB), R2
clrbss:
MOVB R0, (R1)
ADDU $1, R1
BNE R1, R2, clrbss
NOOP
MOVW $0x16, R16
MOVW $0x17, R17
MOVW $0x18, R18
MOVW $0x19, R19
MOVW $0x20, R20
MOVW $0x21, R21
MOVW $0x22, R22
MOVW $0x23, R23
MOVW R0, HI
MOVW R0, LO
MOVW R0, 0(R(MACH)) /* m->machno = 0 */
MOVW R0, R(USER) /* up = nil */
JAL main(SB)
NOOP
PUTC('X', R1, R2)
NOOP
insane:
PUTC('D', R1, R2)
NOOP
TEXT arcs(SB), $256
MOVW R24, 0x80(SP)
MOVW R25, 0x84(SP)
MOVW R26, 0x88(SP)
MOVW R27, 0x8C(SP)
MOVW $SPBADDR, R4
MOVW 0x20(R4), R5
ADDU R1, R5
MOVW (R5), R2
MOVW 16(FP), R7
MOVW 12(FP), R6
MOVW 8(FP), R5
MOVW 4(FP), R4
JAL (R2)
NOOP
MOVW $setR30(SB), R30
MOVW 0x80(SP), R24
MOVW 0x84(SP), R25
MOVW 0x88(SP), R26
MOVW 0x8C(SP), R27
MOVW R2, R1
RETURN
/*
* Take first processor into user mode
* - argument is stack pointer to user
*/
TEXT touser(SB), $-4
MOVW M(STATUS), R4
MOVW $(UTZERO+32), R2 /* header appears in text */
MOVW R2, M(EPC)
MOVW R1, SP
AND $(~KMODEMASK), R4
OR $(KUSER|IE|EXL), R4 /* switch to user mode, intrs on, exc */
MOVW R4, M(STATUS) /* " */
NOOP
ERET /* clears EXL */
NOOP
/* target for JALRHB in BARRIERS */
TEXT ret(SB), $-4
JMP (R22)
NOP
/* the i and d caches may be different sizes, so clean them separately */
TEXT cleancache(SB), $-4
DI(10) /* intrs off, old status -> R10 */
UBARRIERS(7, R7, cchb); /* return to kseg1 (uncached) */
MOVW R0, R1 /* index, not address */
MOVW $ICACHESIZE, R9
iccache:
CACHE PI+IWBI, (R1) /* flush & invalidate I by index */
SUBU $CACHELINESZ, R9
BGTZ R9, iccache
ADDU $CACHELINESZ, R1 /* delay slot */
BARRIERS(7, R7, cc2hb); /* return to kseg0 (cached) */
MOVW R0, R1 /* index, not address */
MOVW $DCACHESIZE, R9
dccache:
CACHE PD+IWBI, (R1) /* flush & invalidate D by index */
SUBU $CACHELINESZ, R9
BGTZ R9, dccache
ADDU $CACHELINESZ, R1 /* delay slot */
SYNC
MOVW R10, M(STATUS)
JRHB(31) /* return and clear all hazards */
/*
* manipulate interrupts
*/
/* enable an interrupt; bit is in R1 */
TEXT intron(SB), $0
MOVW M(STATUS), R2
OR R1, R2
MOVW R2, M(STATUS)
EHB
RETURN
/* disable an interrupt; bit is in R1 */
TEXT introff(SB), $0
MOVW M(STATUS), R2
XOR $-1, R1
AND R1, R2
MOVW R2, M(STATUS)
EHB
RETURN
TEXT splhi(SB), $0
EHB
MOVW R31, 12(R(MACH)) /* save PC in m->splpc */
DI(1) /* old M(STATUS) into R1 */
EHB
RETURN
TEXT splx(SB), $0
EHB
MOVW R31, 12(R(MACH)) /* save PC in m->splpc */
MOVW M(STATUS), R2
AND $IE, R1
AND $~IE, R2
OR R2, R1
MOVW R1, M(STATUS)
EHB
RETURN
TEXT spllo(SB), $0
EHB
EI(1) /* old M(STATUS) into R1 */
EHB
RETURN
TEXT spldone(SB), $0
RETURN
TEXT islo(SB), $0
MOVW M(STATUS), R1
AND $IE, R1
RETURN
TEXT coherence(SB), $-4
BARRIERS(7, R7, cohhb)
SYNC
EHB
RETURN
TEXT idle(SB), $-4
EI(1) /* old M(STATUS) into R1 */
EHB
/* fall through */
TEXT wait(SB), $-4
WAIT
NOP
MOVW R1, M(STATUS) /* interrupts restored */
EHB
RETURN
/*
* process switching
*/
TEXT setlabel(SB), $-4
MOVW SP, 0(R1)
MOVW R31, 4(R1)
MOVW R0, R1
RETURN
TEXT gotolabel(SB), $-4
MOVW 0(R1), SP
MOVW 4(R1), R31
MOVW $1, R1
RETURN
/*
* the tlb routines need to be called at splhi.
*/
TEXT getwired(SB),$0
MOVW M(WIRED), R1
RETURN
TEXT setwired(SB),$0
MOVW R1, M(WIRED)
RETURN
TEXT getrandom(SB),$0
MOVW M(RANDOM), R1
RETURN
TEXT getpagemask(SB),$0
MOVW M(PAGEMASK), R1
RETURN
TEXT setpagemask(SB),$0
MOVW R1, M(PAGEMASK)
MOVW R0, R1 /* prevent accidents */
RETURN
TEXT puttlbx(SB), $0 /* puttlbx(index, virt, phys0, phys1, pagemask) */
MOVW 4(FP), R2
MOVW 8(FP), R3
MOVW 12(FP), R4
MOVW $((2*BY2PG-1) & ~0x1fff), R5
MOVW R2, M(TLBVIRT)
MOVW R3, M(TLBPHYS0)
MOVW R4, M(TLBPHYS1)
MOVW R5, M(PAGEMASK)
MOVW R1, M(INDEX)
NOOP
NOOP
TLBWI
NOOP
RETURN
TEXT tlbvirt(SB), $0
MOVW M(TLBVIRT), R1
NOOP
RETURN
TEXT gettlbx(SB), $0 /* gettlbx(index, &entry) */
MOVW 4(FP), R4
MOVW R1, M(INDEX)
NOOP
NOOP
TLBR
NOOP
NOOP
NOOP
MOVW M(TLBVIRT), R1
MOVW M(TLBPHYS0), R2
MOVW M(TLBPHYS1), R3
NOOP
MOVW R1, 0(R4)
MOVW R2, 4(R4)
MOVW R3, 8(R4)
RETURN
TEXT gettlbp(SB), $0 /* gettlbp(tlbvirt, &entry) */
MOVW 4(FP), R5
MOVW R1, M(TLBVIRT)
NOOP
NOOP
NOOP
TLBP
NOOP
NOOP
MOVW M(INDEX), R1
NOOP
BLTZ R1, gettlbp1
TLBR
NOOP
NOOP
NOOP
MOVW M(TLBVIRT), R2
MOVW M(TLBPHYS0), R3
MOVW M(TLBPHYS1), R4
NOOP
MOVW R2, 0(R5)
MOVW R3, 4(R5)
MOVW R4, 8(R5)
gettlbp1:
RETURN
TEXT gettlbvirt(SB), $0 /* gettlbvirt(index) */
MOVW R1, M(INDEX)
NOOP
NOOP
TLBR
NOOP
NOOP
NOOP
MOVW M(TLBVIRT), R1
NOOP
RETURN
/*
* compute stlb hash index.
*
* M(TLBVIRT) [page & asid] in arg, result in arg.
* stir in swizzled asid; we get best results with asid in both high & low bits.
*/
#define STLBHASH(arg, tmp) \
AND $0xFF, arg, tmp; \
SRL $(PGSHIFT+1), arg; \
XOR tmp, arg; \
SLL $(STLBLOG-8), tmp; \
XOR tmp, arg; \
CONST (STLBSIZE-1, tmp); \
AND tmp, arg
TEXT stlbhash(SB), $0 /* for mmu.c */
STLBHASH(R1, R2)
RETURN
TEXT utlbmiss(SB), $-4
GETMACH(R26)
MOVW R27, 12(R26) /* m->splpc = R27 */
MOVW 16(R26), R27
ADDU $1, R27
MOVW R27,16(R26) /* m->tlbfault++ */
MOVW M(TLBVIRT), R27
NOOP
STLBHASH(R27, R26)
/* scale to a byte index (multiply by 12) */
SLL $1, R27, R26 /* × 2 */
ADDU R26, R27 /* × 3 */
SLL $2, R27 /* × 12 */
GETMACH(R26)
MOVW 4(R26), R26
ADDU R26, R27 /* R27 = &m->stb[hash] */
MOVW M(BADVADDR), R26
NOOP
AND $BY2PG, R26
BNE R26, utlbodd /* odd page? */
NOOP
utlbeven:
MOVW 4(R27), R26 /* R26 = m->stb[hash].phys0 */
BEQ R26, stlbm /* nothing cached? do it the hard way */
NOOP
MOVW R26, M(TLBPHYS0)
MOVW 8(R27), R26 /* R26 = m->stb[hash].phys1 */
JMP utlbcom
MOVW R26, M(TLBPHYS1) /* branch delay slot */
utlbodd:
MOVW 8(R27), R26 /* R26 = m->stb[hash].phys1 */
BEQ R26, stlbm /* nothing cached? do it the hard way */
NOOP
MOVW R26, M(TLBPHYS1)
MOVW 4(R27), R26 /* R26 = m->stb[hash].phys0 */
MOVW R26, M(TLBPHYS0)
utlbcom:
EHB
MOVW M(TLBVIRT), R26
MOVW 0(R27), R27 /* R27 = m->stb[hash].virt */
BEQ R27, stlbm /* nothing cached? do it the hard way */
NOOP
/* is the stlb entry for the right virtual address? */
BNE R26, R27, stlbm /* M(TLBVIRT) != m->stb[hash].virt? */
NOOP
/* if an entry exists, overwrite it, else write a random one */
CONST (PGSZ, R27)
MOVW R27, M(PAGEMASK) /* select page size */
TLBP /* probe tlb */
NOOP
NOOP
MOVW M(INDEX), R26
NOOP
BGEZ R26, utlbindex /* if tlb entry found, rewrite it */
NOOP
MOVW M(RANDOM), R26
MOVW R26, M(INDEX)
utlbindex:
NOOP
NOOP
TLBWI /* write indexed tlb entry */
NOOP
utlbret:
GETMACH(R26)
MOVW 12(R26), R27 /* R27 = m->splpc */
MOVW M(EPC), R26
JMP (R27)
NOOP
stlbm:
GETMACH(R26)
MOVW 12(R26), R27 /* R27 = m->splpc */
/* fall through */
TEXT gevector(SB), $-4
MOVW M(STATUS), R26
NOOP
AND $KUSER, R26
BNE R26, wasuser
MOVW SP, R26 /* delay slot, old SP in R26 */
waskernel:
JMP dosave
SUBU $UREGSIZE, SP /* delay slot, allocate frame on kernel stack */
wasuser: /* get kernel stack for this user process */
GETMACH (SP)
MOVW 8(SP), SP /* m->proc */
SUBU $(UREGSIZE), SP
dosave:
MOVW R31, 0x28(SP)
JAL saveregs(SB)
MOVW R26, 0x10(SP) /* delay slot, save old SP */
GETMACH(R(MACH))
MOVW 8(R(MACH)), R(USER) /* R24 = m->proc */
NOOP
MOVW $setR30(SB), R30
BEQ R26, dosys /* set by saveregs() */
NOOP
dotrap:
MOVW $forkret(SB), R31
JMP trap(SB)
MOVW 4(SP), R1 /* delay slot, first arg to trap() */
dosys:
JAL syscall(SB)
MOVW 4(SP), R1 /* delay slot, first arg to syscall() */
/* fall through */
TEXT forkret(SB), $-4
JAL restregs(SB) /* restores old PC in R26 */
MOVW 0x14(SP), R1 /* delay slot, CAUSE */
MOVW 0x28(SP), R31
JMP (R27)
MOVW 0x10(SP), SP /* delay slot */
/*
* SP-> 0x00 --- (spill R31)
* 0x04 --- (trap()/syscall() arg1)
* 0x08 status
* 0x0C pc
* 0x10 sp/usp
* 0x14 cause
* 0x18 badvaddr
* 0x1C tlbvirt
* 0x20 hi
* 0x24 lo
* 0x28 r31
* .....
* 0x9c r1
*/
TEXT saveregs(SB), $-4
MOVW R1, 0x9C(SP)
MOVW R2, 0x98(SP)
MOVW M(STATUS), R2
ADDU $8, SP, R1
MOVW R1, 0x04(SP) /* arg to base of regs */
MOVW $~KMODEMASK, R1
AND R2, R1
MOVW R1, M(STATUS) /* so we can take another trap */
MOVW R2, 0x08(SP)
MOVW M(EPC), R2
MOVW M(CAUSE), R1
MOVW R2, 0x0C(SP)
MOVW R1, 0x14(SP)
AND $(EXCMASK<<2), R1
SUBU $(CSYS<<2), R1, R26
BEQ R26, notsaved /* is syscall? */
MOVW R27, 0x34(SP) /* delay slot */
MOVW M(BADVADDR), R1
MOVW M(TLBVIRT), R2
MOVW R1, 0x18(SP)
MOVW R2, 0x1C(SP)
MOVW HI, R1
MOVW LO, R2
MOVW R1, 0x20(SP)
MOVW R2, 0x24(SP)
MOVW R25, 0x3C(SP)
MOVW R24, 0x40(SP)
MOVW R23, 0x44(SP)
MOVW R22, 0x48(SP)
MOVW R21, 0x4C(SP)
MOVW R20, 0x50(SP)
MOVW R19, 0x54(SP)
MOVW R18, 0x58(SP)
MOVW R17, 0x5C(SP)
MOVW R16, 0x60(SP)
MOVW R15, 0x64(SP)
MOVW R14, 0x68(SP)
MOVW R13, 0x6C(SP)
MOVW R12, 0x70(SP)
MOVW R11, 0x74(SP)
MOVW R10, 0x78(SP)
MOVW R9, 0x7C(SP)
MOVW R8, 0x80(SP)
MOVW R7, 0x84(SP)
MOVW R6, 0x88(SP)
MOVW R5, 0x8C(SP)
MOVW R4, 0x90(SP)
MOVW R3, 0x94(SP)
notsaved:
MOVW R30, 0x2C(SP)
RET
MOVW R28, 0x30(SP) /* delay slot */
TEXT restregs(SB), $-4
AND $(EXCMASK<<2), R1
SUBU $(CSYS<<2), R1, R26
BEQ R26, notrestored /* is syscall? */
MOVW 0x34(SP), R27 /* delay slot */
MOVW 0x3C(SP), R25
MOVW 0x40(SP), R24
MOVW 0x44(SP), R23
MOVW 0x48(SP), R22
MOVW 0x4C(SP), R21
MOVW 0x50(SP), R20
MOVW 0x54(SP), R19
MOVW 0x58(SP), R18
MOVW 0x5C(SP), R17
MOVW 0x60(SP), R16
MOVW 0x64(SP), R15
MOVW 0x68(SP), R14
MOVW 0x6C(SP), R13
MOVW 0x70(SP), R12
MOVW 0x74(SP), R11
MOVW 0x78(SP), R10
MOVW 0x7C(SP), R9
MOVW 0x80(SP), R8
MOVW 0x84(SP), R7
MOVW 0x88(SP), R6
MOVW 0x8C(SP), R5
MOVW 0x90(SP), R4
MOVW 0x94(SP), R3
MOVW 0x24(SP), R2
MOVW 0x20(SP), R1
MOVW R2, LO
MOVW R1, HI
MOVW 0x98(SP), R2
notrestored:
MOVW 0x08(SP), R1
MOVW R1, M(STATUS)
MOVW 0x0C(SP), R26 /* old PC */
MOVW R26, M(EPC)
MOVW 0x30(SP), R28
MOVW 0x2C(SP), R30
RET
MOVW 0x9C(SP), R1 /* delay slot */
/*
* hardware interrupt vectors
*/
TEXT vector0(SB), $-4
NOOP
CONST (SPBADDR+0x18, R26)
MOVW $eret(SB), R27
MOVW (R26), R26
JMP (R26)
NOOP
TEXT vector180(SB), $-4
NOOP
CONST (SPBADDR+0x14, R26)
MOVW $eret(SB), R27
MOVW (R26), R26
JMP (R26)
NOOP
TEXT eret(SB), $-4
ERET
NOOP
/*
* floating-point stuff
*/
/*
* degenerate floating-point stuff ad9!
*/
TEXT clrfpintr(SB), $0
RETURN
TEXT savefpregs(SB), $0
RETURN
TEXT restfpregs(SB), $0
RETURN
TEXT fcr31(SB), $0 /* fp csr */
MOVW R0, R1
RETURN
/*
* Emulate 68020 test and set: load linked / store conditional
*/
TEXT tas(SB), $0
TEXT _tas(SB), $0
MOVW R1, R2 /* address of key */
tas1:
MOVW $1, R3
LL(2, 1)
NOOP
SC(2, 3)
NOOP
BEQ R3, tas1
NOOP
RETURN
/* used by the semaphore implementation */
TEXT cmpswap(SB), $0
MOVW R1, R2 /* address of key */
MOVW old+4(FP), R3 /* old value */
MOVW new+8(FP), R4 /* new value */
LL(2, 1) /* R1 = (R2) */
NOOP
BNE R1, R3, fail
NOOP
MOVW R4, R1
SC(2, 1) /* (R2) = R1 if (R2) hasn't changed; R1 = success */
NOOP
RETURN
fail:
MOVW R0, R1
RETURN
/*
* cache manipulation
*/
TEXT icflush(SB), $-4 /* icflush(virtaddr, count) */
MOVW 4(FP), R9
DI(10) /* intrs off, old status -> R10 */
UBARRIERS(7, R7, ichb); /* return to kseg1 (uncached) */
ADDU R1, R9 /* R9 = last address */
MOVW $(~0x3f), R8
AND R1, R8 /* R8 = first address, rounded down */
ADDU $0x3f, R9
AND $(~0x3f), R9 /* round last address up */
SUBU R8, R9 /* R9 = revised count */
icflush1: /* primary cache line size is 16 bytes */
CACHE PD+HWB, 0x00(R8)
CACHE PI+HINV, 0x00(R8)
CACHE PD+HWB, 0x10(R8)
CACHE PI+HINV, 0x10(R8)
CACHE PD+HWB, 0x20(R8)
CACHE PI+HINV, 0x20(R8)
CACHE PD+HWB, 0x30(R8)
CACHE PI+HINV, 0x30(R8)
SUBU $0x40, R9
BGTZ R9, icflush1
ADDU $0x40, R8 /* delay slot */
BARRIERS(7, R7, ic2hb); /* return to kseg0 (cached) */
MOVW R10, M(STATUS)
JRHB(31)
TEXT dcflush(SB), $-4 /* dcflush(virtaddr, count) */
MOVW 4(FP), R9
DI(10) /* intrs off, old status -> R10 */
SYNC
EHB
ADDU R1, R9 /* R9 = last address */
MOVW $(~0x3f), R8
AND R1, R8 /* R8 = first address, rounded down */
ADDU $0x3f, R9
AND $(~0x3f), R9 /* round last address up */
SUBU R8, R9 /* R9 = revised count */
dcflush1: /* primary cache line size is 16 bytes */
CACHE PD+HWB, 0x00(R8)
CACHE PD+HWB, 0x10(R8)
CACHE PD+HWB, 0x20(R8)
CACHE PD+HWB, 0x30(R8)
SUBU $0x40, R9
BGTZ R9, dcflush1
ADDU $0x40, R8 /* delay slot */
SYNC
EHB
MOVW R10, M(STATUS)
RETURN
TEXT outl(SB), $0
MOVW 4(FP), R2
MOVW 8(FP), R3
SLL $2, R3
ADDU R2, R3
outl1:
BEQ R2, R3, outl2
MOVW (R2), R4
MOVW R4, (R1)
JMP outl1
ADDU $4, R2
outl2:
RETURN
/*
* access to CP0 registers
*/
TEXT prid(SB), $0
MOVW M(PRID), R1
RETURN
TEXT rdcount(SB), $0
MOVW M(COUNT), R1
RETURN
TEXT wrcount(SB), $0
MOVW R1, M(COUNT)
RETURN
TEXT wrcompare(SB), $0
MOVW R1, M(COMPARE)
RETURN
TEXT rdcompare(SB), $0
MOVW M(COMPARE), R1
RETURN
TEXT getstatus(SB), $0
MOVW M(STATUS), R1
RETURN
TEXT setstatus(SB), $0
MOVW R1, M(STATUS)
EHB
RETURN
TEXT getcause(SB), $-4
MOVW M(CAUSE), R1
RETURN
TEXT getconfig(SB), $-4
MOVW M(CONFIG), R1
RETURN
TEXT getconfig1(SB), $-4
MFC0(CONFIG, 1, 1)
RETURN
TEXT getconfig2(SB), $-4
MFC0(CONFIG, 2, 1)
RETURN
TEXT getconfig3(SB), $-4
MFC0(CONFIG, 3, 1)
RETURN
TEXT getconfig4(SB), $-4
MFC0(CONFIG, 4, 1)
RETURN
TEXT getconfig7(SB), $-4
MFC0(CONFIG, 7, 1)
RETURN
TEXT gethwreg3(SB), $-4
RDHWR(3, 1)
RETURN
TEXT getdebugreg(SB), $0
MOVW M(DEBUGREG), R1
RETURN
TEXT setwatchhi0(SB), $0
MOVW R1, M(WATCHHI)
EHB
RETURN
/*
* beware that the register takes a double-word address, so it's not
* precise to the individual instruction.
*/
TEXT setwatchlo0(SB), $0
MOVW R1, M(WATCHLO)
EHB
RETURN
TEXT getfcr0(SB), $0
MOVW FCR0, R1
RET
/* zoot is just for debug waves */
TEXT zoot(SB), $0
PUTC('W', R1, R2)
NOP
RETURN
GLOBL sanity(SB), $4
DATA sanity(SB)/4, $SANITY
SCHED