.long 0x06040000 /* Cold Start SP */
.long mstart /* Manual Reset PC */
.long 0x06040000 /* Manual Reset SP */
- .long main_err /* Illegal instruction */
- .long 0x00000000 /* reserved */
- .long main_err /* Invalid slot instruction */
- .long 0x20100400 /* reserved */
- .long 0x20100420 /* reserved */
- .long main_err /* CPU address error */
- .long main_err /* DMA address error */
- .long main_err /* NMI vector */
- .long main_err /* User break vector */
- .space 76 /* reserved */
- .long main_err /* TRAPA #32 */
- .long main_err /* TRAPA #33 */
- .long main_err /* TRAPA #34 */
- .long main_err /* TRAPA #35 */
- .long main_err /* TRAPA #36 */
- .long main_err /* TRAPA #37 */
- .long main_err /* TRAPA #38 */
- .long main_err /* TRAPA #39 */
- .long main_err /* TRAPA #40 */
- .long main_err /* TRAPA #41 */
- .long main_err /* TRAPA #42 */
- .long main_err /* TRAPA #43 */
- .long main_err /* TRAPA #44 */
- .long main_err /* TRAPA #45 */
- .long main_err /* TRAPA #46 */
- .long main_err /* TRAPA #47 */
- .long main_err /* TRAPA #48 */
- .long main_err /* TRAPA #49 */
- .long main_err /* TRAPA #50 */
- .long main_err /* TRAPA #51 */
- .long main_err /* TRAPA #52 */
- .long main_err /* TRAPA #53 */
- .long main_err /* TRAPA #54 */
- .long main_err /* TRAPA #55 */
- .long main_err /* TRAPA #56 */
- .long main_err /* TRAPA #57 */
- .long main_err /* TRAPA #58 */
- .long main_err /* TRAPA #59 */
- .long main_err /* TRAPA #60 */
- .long main_err /* TRAPA #61 */
- .long main_err /* TRAPA #62 */
- .long main_err /* TRAPA #63 */
+ .long master_e4 /* Illegal instruction */
+ .long master_e5 /* reserved */
+ .long master_e6 /* Invalid slot instruction */
+ .long master_e7 /* reserved */
+ .long master_e8 /* reserved */
+ .long master_e9 /* CPU address error */
+ .long master_e10 /* DMA address error */
+ .long master_e11 /* NMI vector */
+ .long master_e12 /* User break vector */
+.rept 19
+ .long main_err /* reserved */
+.endr
+.rept 32
+ .long main_err /* TRAPA #32-63 */
+.endr
.long main_irq /* Level 1 IRQ */
.long main_irq /* Level 2 & 3 IRQ's */
.long main_irq /* Level 4 & 5 IRQ's */
.long main_irq /* H Blank interupt */
.long main_irq /* V Blank interupt */
.long main_irq /* Reset Button */
- .long main_irq /* DMA1 TE INT */
+.rept 56
+ .long main_err /* peripherals */
+.endr
-! Slave Vector Base Table at 0x06000124
+! Slave Vector Base Table at 0x06000200
.long sstart /* Cold Start PC */
.long 0x0603f800 /* Cold Start SP */
.long sstart /* Manual Reset PC */
.long 0x0603f800 /* Manual Reset SP */
- .long slav_err /* Illegal instruction */
- .long 0x00000000 /* reserved */
- .long slav_err /* Invalid slot instruction */
- .long 0x20100400 /* reserved */
- .long 0x20100420 /* reserved */
- .long slav_err /* CPU address error */
- .long slav_err /* DMA address error */
- .long slav_err /* NMI vector */
- .long slav_err /* User break vector */
- .space 76 /* reserved */
- .long slav_err /* TRAPA #32 */
- .long slav_err /* TRAPA #33 */
- .long slav_err /* TRAPA #34 */
- .long slav_err /* TRAPA #35 */
- .long slav_err /* TRAPA #36 */
- .long slav_err /* TRAPA #37 */
- .long slav_err /* TRAPA #38 */
- .long slav_err /* TRAPA #39 */
- .long slav_err /* TRAPA #40 */
- .long slav_err /* TRAPA #41 */
- .long slav_err /* TRAPA #42 */
- .long slav_err /* TRAPA #43 */
- .long slav_err /* TRAPA #44 */
- .long slav_err /* TRAPA #45 */
- .long slav_err /* TRAPA #46 */
- .long slav_err /* TRAPA #47 */
- .long slav_err /* TRAPA #48 */
- .long slav_err /* TRAPA #49 */
- .long slav_err /* TRAPA #50 */
- .long slav_err /* TRAPA #51 */
- .long slav_err /* TRAPA #52 */
- .long slav_err /* TRAPA #53 */
- .long slav_err /* TRAPA #54 */
- .long slav_err /* TRAPA #55 */
- .long slav_err /* TRAPA #56 */
- .long slav_err /* TRAPA #57 */
- .long slav_err /* TRAPA #58 */
- .long slav_err /* TRAPA #59 */
- .long slav_err /* TRAPA #60 */
- .long slav_err /* TRAPA #61 */
- .long slav_err /* TRAPA #62 */
- .long slav_err /* TRAPA #63 */
- .long slav_irq /* Level 1 IRQ */
- .long slav_irq /* Level 2 & 3 IRQ's */
- .long slav_irq /* Level 4 & 5 IRQ's */
- .long slav_irq /* PWM interupt */
- .long slav_irq /* Command interupt */
- .long slav_irq /* H Blank interupt */
- .long slav_irq /* V Blank interupt */
- .long slav_irq /* Reset Button */
+ .long slave_e4 /* Illegal instruction */
+ .long slave_e5 /* reserved */
+ .long slave_e6 /* Invalid slot instruction */
+ .long slave_e7 /* reserved */
+ .long slave_e8 /* reserved */
+ .long slave_e9 /* CPU address error */
+ .long slave_e10 /* DMA address error */
+ .long slave_e11 /* NMI vector */
+ .long slave_e12 /* User break vector */
+.rept 19
+ .long slave_err /* reserved */
+.endr
+.rept 32
+ .long slave_err /* TRAPA #32-63 */
+.endr
+ .long slave_irq /* Level 1 IRQ */
+ .long slave_irq /* Level 2 & 3 IRQ's */
+ .long slave_irq /* Level 4 & 5 IRQ's */
+ .long slave_irq /* PWM interupt */
+ .long slave_irq /* Command interupt */
+ .long slave_irq /* H Blank interupt */
+ .long slave_irq /* V Blank interupt */
+ .long slave_irq /* Reset Button */
+.rept 56
+ .long slave_err /* peripherals */
+.endr
+
+! trashes r0
+.macro mov_bc const ofs reg
+ mov #\const, r0
+.if \ofs == 0
+ mov.b r0, @\reg
+.else
+ mov.b r0, @(\ofs, \reg)
+.endif
+.endm
! Stacks set up by BIOS
-! The main SH2 starts here at 0x06000244
+! The main SH2 starts here at 0x06000400
mstart:
- bra mcont
+ bra xstart
mov #0, r4
-! The slave SH2 starts here at 0x06000248
+! The slave SH2 starts here at 0x06000404
sstart:
- sleep
-! broken
- bra xstart
mov #1, r4
-mcont:
-
xstart:
- mov.l l_cctl, r0
- mov #0x11, r1
- mov.b r1, @r0
+.if 0
+! cache init - done by BIOS with single 0x11 write
+ mov.l l_cctl, r1 /* cache */
+ mov_bc 0x00, 0, r1 /* disable */
+ mov.b @r1, r0 /* dummy read */
+ mov_bc 0x10, 0, r1 /* purge */
+ mov.b @r1, r0
+ mov_bc 0x01, 0, r1 /* enable */
+.endif
+ mov #0xd0, r0 /* enable irqs */
+ ldc r0, sr
mov.l l_main_c, r0
jmp @r0
nop
+main_irq:
+ mov.l r0, @-r15
+
+ stc sr, r0 /* SR holds IRQ level in I3-I0 */
+ shlr2 r0
+ and #0x38,r0
+ cmp/eq #0x38,r0
+ bt main_irq_vres
+! todo
+0:
+ bra 0b
+ nop
+
+main_irq_vres:
+ mov.w r0, @(0x14, gbr) /* ack */
+ mov.b @(7, gbr), r0 /* RV */
+ tst #1, r0
+ bt main_irq_ret
+
+! Try to set FTOB pin that's wired to 32X hard reset.
+! Doesn't seem to be working right though, it somehow disturbs
+! 68k reset PC fetch which mysteriously ends up at range
+! 2c8 - 304 in multiples of 4, proportionally to reset delay
+! (0 - ~300 (?) sh2 cycles). Longer delay just hangs, presumably
+! at 880200?
+ mov.l l_frt, r1
+ mov_bc 0xf1, 7, r1 /* TOCR sel OCRB, pin on B match */
+ mov #0, r0
+ mov.b r0, @(4, r1) /* OCRB H - output compare B */
+ mov.b r0, @(5, r1) /* OCRB L */
+ mov.b r0, @(2, r1) /* FRC H */
+ mov.b r0, @(3, r1) /* FRC L */
+ mov.b @(7, r1), r0
+! sleep - docs say not to use
+! sleep
+0:
+ bra 0b
+ nop
+
+main_irq_ret:
+ rte
+ mov.l @r15+, r0
+
+.global _read_frt
+_read_frt:
+ mov.l l_frt, r2
+ mov.b @(2, r2), r0
+ extu.b r0, r1
+ mov.b @(3, r2), r0
+ extu.b r0, r0
+ shll8 r1
+ rts
+ or r1, r0
+
.align 2
l_cctl:
.long 0xFFFFFE92
+l_frt:
+ .long 0xFFFFFE10
l_main_c:
.long _main_c
.global _start
_start:
+main_err:
+ bra do_exc_master
+ mov #0xff, r0
+slave_err:
+slave_irq:
+ bra do_exc_slave
+ mov #0xff, r0
+
+.macro exc_master num
+master_e\num:
+ bra do_exc_master
+ mov #\num, r0
+.endm
+
+.macro exc_slave num
+slave_e\num:
+ bra do_exc_slave
+ mov #\num, r0
+.endm
+
+exc_master 4
+exc_master 5
+exc_master 6
+exc_master 7
+exc_master 8
+exc_master 9
+exc_master 10
+exc_master 11
+exc_master 12
+
+exc_slave 4
+exc_slave 5
+exc_slave 6
+exc_slave 7
+exc_slave 8
+exc_slave 9
+exc_slave 10
+exc_slave 11
+exc_slave 12
+
+do_exc_master:
+ mov.w r0, @(0x2c, gbr)
+0:
+ bra 0b
+ nop
+
+do_exc_slave:
+ mov.w r0, @(0x2e, gbr)
+0:
+ bra 0b
+ nop
+
.global _spin
_spin:
dt r4
rts
nop
-main_err:
-main_irq:
-slav_err:
-slav_irq:
-0:
- bra 0b
- nop
-
! vim:ts=8:sw=8:expandtab
notaz.gp2x.de / megadrive.git / blobdiff