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651e91ece6
Genesis-Plus-GX/source/cart_hw/svp/ssp16.c
ekeeke31 651e91ece6 Reverted to r598
2011-07-13 22:49:52 +00:00

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/*
basic, incomplete SSP160x (SSP1601?) interpreter
with SVP memory controller emu
(c) Copyright 2008, Grazvydas "notaz" Ignotas
Free for non-commercial use.
For commercial use, separate licencing terms must be obtained.
Modified for Genesis Plus GX (Eke-Eke), added big endian support, fixed mode & addr
*/
/*
* Register info
*
* 0. "-"
* size: 16
* desc: Constant register with all bits set (0xffff).
*
* 1. "X"
* size: 16
* desc: Generic register. When set, updates P (P = X * Y * 2)
*
* 2. "Y"
* size: 16
* desc: Generic register. When set, updates P (P = X * Y * 2)
*
* 3. "A"
* size: 32
* desc: Accumulator.
*
* 4. "ST"
* size: 16
* desc: Status register. From MAME: bits 0-9 are CONTROL, other FLAG
* fedc ba98 7654 3210
* 210 - RPL (?) "Loop size". If non-zero, makes (rX+) and (rX-) respectively
* modulo-increment and modulo-decrement. The value shows which
* power of 2 to use, i.e. 4 means modulo by 16.
* (e: fir16_32.sc, IIR_4B.SC, DECIM.SC)
* 43 - RB (?)
* 5 - GP0_0 (ST5?) Changed before acessing PM0 (affects banking?).
* 6 - GP0_1 (ST6?) Cleared before acessing PM0 (affects banking?). Set after.
* datasheet says these (5,6) bits correspond to hardware pins.
* 7 - IE (?) Not directly used by SVP code (never set, but preserved)?
* 8 - OP (?) Not used by SVP code (only cleared)? (MAME: saturated value
* (probably means clamping? i.e. 0x7ffc + 9 -> 0x7fff))
* 9 - MACS (?) Not used by SVP code (only cleared)? (e: "mac shift")
* a - GPI_0 Interrupt 0 enable/status?
* b - GPI_1 Interrupt 1 enable/status?
* c - L L flag. Carry?
* d - Z Zero flag.
* e - OV Overflow flag.
* f - N Negative flag.
* seen directly changing code sequences:
* ldi ST, 0 ld A, ST ld A, ST ld A, ST ldi st, 20h
* ldi ST, 60h ori A, 60h and A, E8h and A, E8h
* ld ST, A ld ST, A ori 3
* ld ST, A
*
* 5. "STACK"
* size: 16
* desc: hw stack of 6 levels (according to datasheet)
*
* 6. "PC"
* size: 16
* desc: Program counter.
*
* 7. "P"
* size: 32
* desc: multiply result register. P = X * Y * 2
* probably affected by MACS bit in ST.
*
* 8. "PM0" (PM from PMAR name from Tasco's docs)
* size: 16?
* desc: Programmable Memory access register.
* On reset, or when one (both?) GP0 bits are clear,
* acts as status for XST, mapped at 015004 at 68k side:
* bit0: ssp has written something to XST (cleared when 015004 is read)
* bit1: 68k has written something through a1500{0|2} (cleared on PM0 read)
*
* 9. "PM1"
* size: 16?
* desc: Programmable Memory access register.
* This reg. is only used as PMAR.
*
* 10. "PM2"
* size: 16?
* desc: Programmable Memory access register.
* This reg. is only used as PMAR.
*
* 11. "XST"
* size: 16?
* desc: eXternal STate. Mapped to a15000 and a15002 at 68k side.
* Can be programmed as PMAR? (only seen in test mode code)
* Affects PM0 when written to?
*
* 12. "PM4"
* size: 16?
* desc: Programmable Memory access register.
* This reg. is only used as PMAR. The most used PMAR by VR.
*
* 13. (unused by VR)
*
* 14. "PMC" (PMC from PMAC name from Tasco's docs)
* size: 32?
* desc: Programmable Memory access Control. Set using 2 16bit writes,
* first address, then mode word. After setting PMAC, PMAR sould
* be blind accessed (ld -, PMx or ld PMx, -) to program it for
* reading and writing respectively.
* Reading the register also shifts it's state (from "waiting for
* address" to "waiting for mode" and back). Reads always return
* address related to last PMx register accressed.
* (note: addresses do not wrap).
*
* 15. "AL"
* size: 16
* desc: Accumulator Low. 16 least significant bits of accumulator.
* (normally reading acc (ld X, A) you get 16 most significant bits).
*
*
* There are 8 8-bit pointer registers rX. r0-r3 (ri) point to RAM0, r4-r7 (rj) point to RAM1.
* They can be accessed directly, or 2 indirection levels can be used [ (rX), ((rX)) ],
* which work similar to * and ** operators in C, only they use different memory banks and
* ((rX)) also does post-increment. First indirection level (rX) accesses RAMx, second accesses
* program memory at address read from (rX), and increments value in (rX).
*
* r0,r1,r2,r4,r5,r6 can be modified [ex: ldi r0, 5].
* 3 modifiers can be applied (optional):
* + : post-increment [ex: ld a, (r0+) ]. Can be made modulo-increment by setting RPL bits in ST.
* - : post-decrement. Can be made modulo-decrement by setting RPL bits in ST (not sure).
* +!: post-increment, unaffected by RPL (probably).
* These are only used on 1st indirection level, so things like [ld a, ((r0+))] and [ld X, r6-]
* ar probably invalid.
*
* r3 and r7 are special and can not be changed (at least Samsung samples and SVP code never do).
* They are fixed to the start of their RAM banks. (They are probably changeable for ssp1605+,
* Samsung's old DSP page claims that).
* 1 of these 4 modifiers must be used (short form direct addressing?):
* |00: RAMx[0] [ex: (r3|00), 0] (based on sample code)
* |01: RAMx[1]
* |10: RAMx[2] ? maybe 10h? accortding to Div_c_dp.sc, 2
* |11: RAMx[3]
*
*
* Instruction notes
*
* ld a, * doesn't affect flags! (e: A_LAW.SC, Div_c_dp.sc)
*
* mld (rj), (ri) [, b]
* operation: A = 0; P = (rj) * (ri)
* notes: based on IIR_4B.SC sample. flags? what is b???
*
* mpya (rj), (ri) [, b]
* name: multiply and add?
* operation: A += P; P = (rj) * (ri)
*
* mpys (rj), (ri), b
* name: multiply and subtract?
* notes: not used by VR code.
*
* mod cond, op
* mod cond, shr does arithmetic shift
*
* 'ld -, AL' and probably 'ld AL, -' are for dummy assigns
*
* memory map:
* 000000 - 1fffff ROM, accessable by both
* 200000 - 2fffff unused?
* 300000 - 31ffff DRAM, both
* 320000 - 38ffff unused?
* 390000 - 3907ff IRAM. can only be accessed by ssp?
* 390000 - 39ffff similar mapping to "cell arrange" in Sega CD, 68k only?
* 3a0000 - 3affff similar mapping to "cell arrange" in Sega CD, a bit different
*
* 30fe02 - 0 if SVP busy, 1 if done (set by SVP, checked and cleared by 68k)
* 30fe06 - also sync related.
* 30fe08 - job number [1-12] for SVP. 0 means no job. Set by 68k, read-cleared by SVP.
*
* + figure out if 'op A, P' is 32bit (nearly sure it is)
* * does mld, mpya load their operands into X and Y?
* * OP simm
*
* Assumptions in this code
* P is not directly writeable
* flags correspond to full 32bit accumulator
* only Z and N status flags are emulated (others unused by SVP)
* modifiers for 'OP a, ri' are ignored (invalid?/not used by SVP)
* 'ld d, (a)' loads from program ROM
*/
#include "shared.h"
#define u32 unsigned int
//#define USE_DEBUGGER
// 0
#define rX ssp->gr[SSP_X].h
#define rY ssp->gr[SSP_Y].h
#define rA ssp->gr[SSP_A].h
#define rST ssp->gr[SSP_ST].h // 4
#define rSTACK ssp->gr[SSP_STACK].h
#define rPC ssp->gr[SSP_PC].h
#define rP ssp->gr[SSP_P]
#define rPM0 ssp->gr[SSP_PM0].h // 8
#define rPM1 ssp->gr[SSP_PM1].h
#define rPM2 ssp->gr[SSP_PM2].h
#define rXST ssp->gr[SSP_XST].h
#define rPM4 ssp->gr[SSP_PM4].h // 12
// 13
#define rPMC ssp->gr[SSP_PMC] // will keep addr in .h, mode in .l
#define rAL ssp->gr[SSP_A].l
#define rA32 ssp->gr[SSP_A].v
#define rIJ ssp->r
#define IJind (((op>>6)&4)|(op&3))
#define GET_PC() (PC - (unsigned short *)svp->iram_rom)
#define GET_PPC_OFFS() ((unsigned int)PC - (unsigned int)svp->iram_rom - 2)
#define SET_PC(d) PC = (unsigned short *)svp->iram_rom + d
#define REG_READ(r) (((r) <= 4) ? ssp->gr[r].h : read_handlers[r]())
#define REG_WRITE(r,d) { \
int r1 = r; \
if (r1 >= 4) write_handlers[r1](d); \
else if (r1 > 0) ssp->gr[r1].h = d; \
}
// flags
#define SSP_FLAG_L (1<<0xc)
#define SSP_FLAG_Z (1<<0xd)
#define SSP_FLAG_V (1<<0xe)
#define SSP_FLAG_N (1<<0xf)
// update ZN according to 32bit ACC.
#define UPD_ACC_ZN \
rST &= ~(SSP_FLAG_Z|SSP_FLAG_N); \
if (!rA32) rST |= SSP_FLAG_Z; \
else rST |= (rA32>>16)&SSP_FLAG_N;
// it seems SVP code never checks for L and OV, so we leave them out.
// rST |= (t>>4)&SSP_FLAG_L;
#define UPD_LZVN \
rST &= ~(SSP_FLAG_L|SSP_FLAG_Z|SSP_FLAG_V|SSP_FLAG_N); \
if (!rA32) rST |= SSP_FLAG_Z; \
else rST |= (rA32>>16)&SSP_FLAG_N;
// standard cond processing.
// again, only Z and N is checked, as SVP doesn't seem to use any other conds.
#define COND_CHECK \
switch (op&0xf0) { \
case 0x00: cond = 1; break; /* always true */ \
case 0x50: cond = !((rST ^ (op<<5)) & SSP_FLAG_Z); break; /* Z matches f(?) bit */ \
case 0x70: cond = !((rST ^ (op<<7)) & SSP_FLAG_N); break; /* N matches f(?) bit */ \
default:elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: unimplemented cond @ %04x", GET_PPC_OFFS()); break; \
}
// ops with accumulator.
// how is low word really affected by these?
// nearly sure 'ld A' doesn't affect flags
#define OP_LDA(x) \
rA = x
#define OP_LDA32(x) \
rA32 = x
#define OP_SUBA(x) { \
rA32 -= (x) << 16; \
UPD_LZVN \
}
#define OP_SUBA32(x) { \
rA32 -= (x); \
UPD_LZVN \
}
#define OP_CMPA(x) { \
u32 t = rA32 - ((x) << 16); \
rST &= ~(SSP_FLAG_L|SSP_FLAG_Z|SSP_FLAG_V|SSP_FLAG_N); \
if (!t) rST |= SSP_FLAG_Z; \
else rST |= (t>>16)&SSP_FLAG_N; \
}
#define OP_CMPA32(x) { \
u32 t = rA32 - (x); \
rST &= ~(SSP_FLAG_L|SSP_FLAG_Z|SSP_FLAG_V|SSP_FLAG_N); \
if (!t) rST |= SSP_FLAG_Z; \
else rST |= (t>>16)&SSP_FLAG_N; \
}
#define OP_ADDA(x) { \
rA32 += (x) << 16; \
UPD_LZVN \
}
#define OP_ADDA32(x) { \
rA32 += (x); \
UPD_LZVN \
}
#define OP_ANDA(x) \
rA32 &= (x) << 16; \
UPD_ACC_ZN
#define OP_ANDA32(x) \
rA32 &= (x); \
UPD_ACC_ZN
#define OP_ORA(x) \
rA32 |= (x) << 16; \
UPD_ACC_ZN
#define OP_ORA32(x) \
rA32 |= (x); \
UPD_ACC_ZN
#define OP_EORA(x) \
rA32 ^= (x) << 16; \
UPD_ACC_ZN
#define OP_EORA32(x) \
rA32 ^= (x); \
UPD_ACC_ZN
#define OP_CHECK32(OP) { \
if ((op & 0x0f) == SSP_P) { /* A <- P */ \
read_P(); /* update P */ \
OP(rP.v); \
break; \
} \
if ((op & 0x0f) == SSP_A) { /* A <- A */ \
OP(rA32); \
break; \
} \
}
static ssp1601_t *ssp = NULL;
static unsigned short *PC;
static int g_cycles;
#ifdef USE_DEBUGGER
static int running = 0;
static int last_iram = 0;
#endif
// -----------------------------------------------------
// register i/o handlers
// 0-4, 13
static u32 read_unknown(void)
{
#ifdef LOG_SVP
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME: unknown read @ %04x", GET_PPC_OFFS());
#endif
return 0;
}
static void write_unknown(u32 d)
{
#ifdef LOG_SVP
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME: unknown write @ %04x", GET_PPC_OFFS());
#endif
}
// 4
static void write_ST(u32 d)
{
//if ((rST ^ d) & 0x0007) elprintf(EL_SVP, "ssp RPL %i -> %i @ %04x", rST&7, d&7, GET_PPC_OFFS());
#ifdef LOG_SVP
if ((rST ^ d) & 0x0f98) elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME ST %04x -> %04x @ %04x", rST, d, GET_PPC_OFFS());
#endif
rST = d;
}
// 5
static u32 read_STACK(void)
{
--rSTACK;
if ((short)rSTACK < 0) {
rSTACK = 5;
#ifdef LOG_SVP
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME: stack underflow! (%i) @ %04x", rSTACK, GET_PPC_OFFS());
#endif
}
return ssp->stack[rSTACK];
}
static void write_STACK(u32 d)
{
if (rSTACK >= 6) {
#ifdef LOG_SVP
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME: stack overflow! (%i) @ %04x", rSTACK, GET_PPC_OFFS());
#endif
rSTACK = 0;
}
ssp->stack[rSTACK++] = d;
}
// 6
static u32 read_PC(void)
{
//g_cycles--;
return GET_PC();
}
static void write_PC(u32 d)
{
SET_PC(d);
g_cycles--;
}
// 7
static u32 read_P(void)
{
int m1 = (signed short)rX;
int m2 = (signed short)rY;
rP.v = (m1 * m2 * 2);
return rP.h;
}
// -----------------------------------------------------
static int get_inc(int mode)
{
int inc = (mode >> 11) & 7;
if (inc != 0) {
if (inc != 7) inc--;
//inc = (1<<16) << inc; // 0 1 2 4 8 16 32 128
inc = 1 << inc; // 0 1 2 4 8 16 32 128
if (mode & 0x8000) inc = -inc; // decrement mode
}
return inc;
}
#define overwite_write(dst, d) \
{ \
if (d & 0xf000) { dst &= ~0xf000; dst |= d & 0xf000; } \
if (d & 0x0f00) { dst &= ~0x0f00; dst |= d & 0x0f00; } \
if (d & 0x00f0) { dst &= ~0x00f0; dst |= d & 0x00f0; } \
if (d & 0x000f) { dst &= ~0x000f; dst |= d & 0x000f; } \
}
static u32 pm_io(int reg, int write, u32 d)
{
if (ssp->emu_status & SSP_PMC_SET)
{
// this MUST be blind r or w
if ((*(PC-1) & 0xff0f) && (*(PC-1) & 0xfff0)) {
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: tried to set PM%i (%c) with non-blind i/o %08x @ %04x",
reg, write ? 'w' : 'r', rPMC.v, GET_PPC_OFFS());
#endif
ssp->emu_status &= ~SSP_PMC_SET;
return 0;
}
#ifdef LOG_SVP
elprintf(EL_SVP, "PM%i (%c) set to %08x @ %04x", reg, write ? 'w' : 'r', rPMC.v, GET_PPC_OFFS());
#endif
ssp->pmac_read[write ? reg + 6 : reg] = rPMC.v;
ssp->emu_status &= ~SSP_PMC_SET;
#ifdef LOG_SVP
if ((rPMC.v & 0x7f) == 0x1c && (rPMC.v & 0x7fff0000) == 0) {
elprintf(EL_SVP, "ssp IRAM copy from %06x", (ssp->RAM1[0]-1)<<1);
#ifdef USE_DEBUGGER
last_iram = (ssp->RAM1[0]-1)<<1;
#endif
}
#endif
return 0;
}
// just in case
if (ssp->emu_status & SSP_PMC_HAVE_ADDR) {
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: PM%i (%c) with only addr set @ %04x",
reg, write ? 'w' : 'r', GET_PPC_OFFS());
#endif
ssp->emu_status &= ~SSP_PMC_HAVE_ADDR;
}
if (reg == 4 || (rST & 0x60))
{
#ifdef LOG_SVP
#define CADDR ((((mode<<16)&0x7f0000)|addr)<<1)
#endif
unsigned short *dram = (unsigned short *)svp->dram;
if (write)
{
/*int mode = ssp->pmac_write[reg]&0xffff;
int addr = ssp->pmac_write[reg]>>16;*/
int addr = ssp->pmac_write[reg]&0xffff;
int mode = ssp->pmac_write[reg]>>16;
#ifdef LOG_SVP
if ((mode & 0xb800) == 0xb800)
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: mode %04x", mode);
#endif
if ((mode & 0x43ff) == 0x0018) // DRAM
{
int inc = get_inc(mode);
#ifdef LOG_SVP
elprintf(EL_SVP, "ssp PM%i DRAM w [%06x] %04x (inc %i, ovrw %i)",
reg, CADDR, d, inc >> 16, (mode>>10)&1);
#endif
if (mode & 0x0400) {
overwite_write(dram[addr], d);
} else dram[addr] = d;
ssp->pmac_write[reg] += inc;
}
else if ((mode & 0xfbff) == 0x4018) // DRAM, cell inc
{
#ifdef LOG_SVP
elprintf(EL_SVP, "ssp PM%i DRAM w [%06x] %04x (cell inc, ovrw %i) @ %04x",
reg, CADDR, d, (mode>>10)&1, GET_PPC_OFFS());
#endif
if (mode & 0x0400) {
overwite_write(dram[addr], d);
} else dram[addr] = d;
//ssp->pmac_write[reg] += (addr&1) ? (31<<16) : (1<<16);
ssp->pmac_write[reg] += (addr&1) ? 31 : 1;
}
else if ((mode & 0x47ff) == 0x001c) // IRAM
{
int inc = get_inc(mode);
#ifdef LOG_SVP
if ((addr&0xfc00) != 0x8000)
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: invalid IRAM addr: %04x", addr<<1);
elprintf(EL_SVP, "ssp IRAM w [%06x] %04x (inc %i)", (addr<<1)&0x7ff, d, inc >> 16);
#endif
((unsigned short *)svp->iram_rom)[addr&0x3ff] = d;
ssp->pmac_write[reg] += inc;
}
#ifdef LOG_SVP
else
{
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: PM%i unhandled write mode %04x, [%06x] %04x @ %04x",
reg, mode, CADDR, d, GET_PPC_OFFS());
}
#endif
}
else
{
/*int mode = ssp->pmac_read[reg]&0xffff;
int addr = ssp->pmac_read[reg]>>16;*/
int addr = ssp->pmac_read[reg]&0xffff;
int mode = ssp->pmac_read[reg]>>16;
if ((mode & 0xfff0) == 0x0800) // ROM, inc 1, verified to be correct
{
#ifdef LOG_SVP
elprintf(EL_SVP, "ssp ROM r [%06x] %04x", CADDR,
((unsigned short *)cart.rom)[addr|((mode&0xf)<<16)]);
#endif
/*if ((signed int)ssp->pmac_read[reg] >> 16 == -1) ssp->pmac_read[reg]++;
ssp->pmac_read[reg] += 1<<16;*/
if ((signed int)(ssp->pmac_read[reg] & 0xffff) == -1) ssp->pmac_read[reg] += 1<<16;
ssp->pmac_read[reg] ++;
d = ((unsigned short *)cart.rom)[addr|((mode&0xf)<<16)];
}
else if ((mode & 0x47ff) == 0x0018) // DRAM
{
int inc = get_inc(mode);
#ifdef LOG_SVP
elprintf(EL_SVP, "ssp PM%i DRAM r [%06x] %04x (inc %i)", reg, CADDR, dram[addr], inc >> 16);
#endif
d = dram[addr];
ssp->pmac_read[reg] += inc;
}
else
{
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: PM%i unhandled read mode %04x, [%06x] @ %04x",
reg, mode, CADDR, GET_PPC_OFFS());
#endif
d = 0;
}
}
// PMC value corresponds to last PMR accessed (not sure).
rPMC.v = ssp->pmac_read[write ? reg + 6 : reg];
return d;
}
return (u32)-1;
}
// 8
static u32 read_PM0(void)
{
u32 d = pm_io(0, 0, 0);
if (d != (u32)-1) return d;
#ifdef LOG_SVP
elprintf(EL_SVP, "PM0 raw r %04x @ %04x", rPM0, GET_PPC_OFFS());
#endif
d = rPM0;
if (!(d & 2) && (GET_PPC_OFFS() == 0x800 || GET_PPC_OFFS() == 0x1851E)) {
ssp->emu_status |= SSP_WAIT_PM0;
#ifdef LOG_SVP
elprintf(EL_SVP, "det TIGHT loop: PM0");
#endif
}
rPM0 &= ~2; // ?
return d;
}
static void write_PM0(u32 d)
{
u32 r = pm_io(0, 1, d);
if (r != (u32)-1) return;
#ifdef LOG_SVP
elprintf(EL_SVP, "PM0 raw w %04x @ %04x", d, GET_PPC_OFFS());
#endif
rPM0 = d;
}
// 9
static u32 read_PM1(void)
{
u32 d = pm_io(1, 0, 0);
if (d != (u32)-1) return d;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM1 raw r %04x @ %04x", rPM1, GET_PPC_OFFS());
#endif
return rPM1;
}
static void write_PM1(u32 d)
{
u32 r = pm_io(1, 1, d);
if (r != (u32)-1) return;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM1 raw w %04x @ %04x", d, GET_PPC_OFFS());
#endif
rPM1 = d;
}
// 10
static u32 read_PM2(void)
{
u32 d = pm_io(2, 0, 0);
if (d != (u32)-1) return d;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM2 raw r %04x @ %04x", rPM2, GET_PPC_OFFS());
#endif
return rPM2;
}
static void write_PM2(u32 d)
{
u32 r = pm_io(2, 1, d);
if (r != (u32)-1) return;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM2 raw w %04x @ %04x", d, GET_PPC_OFFS());
#endif
rPM2 = d;
}
// 11
static u32 read_XST(void)
{
// can be removed?
u32 d = pm_io(3, 0, 0);
if (d != (u32)-1) return d;
#ifdef LOG_SVP
elprintf(EL_SVP, "XST raw r %04x @ %04x", rXST, GET_PPC_OFFS());
#endif
return rXST;
}
static void write_XST(u32 d)
{
// can be removed?
u32 r = pm_io(3, 1, d);
if (r != (u32)-1) return;
#ifdef LOG_SVP
elprintf(EL_SVP, "XST raw w %04x @ %04x", d, GET_PPC_OFFS());
#endif
rPM0 |= 1;
rXST = d;
}
// 12
static u32 read_PM4(void)
{
u32 d = pm_io(4, 0, 0);
if (d == 0) {
switch (GET_PPC_OFFS()) {
case 0x0854:
ssp->emu_status |= SSP_WAIT_30FE08;
#ifdef LOG_SVP
elprintf(EL_SVP, "det TIGHT loop: [30fe08]");
#endif
break;
case 0x4f12:
ssp->emu_status |= SSP_WAIT_30FE06;
#ifdef LOG_SVP
elprintf(EL_SVP, "det TIGHT loop: [30fe06]");
#endif
break;
}
}
if (d != (u32)-1) return d;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM4 raw r %04x @ %04x", rPM4, GET_PPC_OFFS());
#endif
return rPM4;
}
static void write_PM4(u32 d)
{
u32 r = pm_io(4, 1, d);
if (r != (u32)-1) return;
// can be removed?
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "PM4 raw w %04x @ %04x", d, GET_PPC_OFFS());
#endif
rPM4 = d;
}
// 14
static u32 read_PMC(void)
{
#ifdef LOG_SVP
elprintf(EL_SVP, "PMC r a %04x (st %c) @ %04x", rPMC.h,
(ssp->emu_status & SSP_PMC_HAVE_ADDR) ? 'm' : 'a', GET_PPC_OFFS());
#endif
if (ssp->emu_status & SSP_PMC_HAVE_ADDR) {
//if (ssp->emu_status & SSP_PMC_SET)
// elprintf(EL_ANOMALY|EL_SVP, "prev PMC not used @ %04x", GET_PPC_OFFS());
ssp->emu_status |= SSP_PMC_SET;
ssp->emu_status &= ~SSP_PMC_HAVE_ADDR;
//return ((rPMC.h << 4) & 0xfff0) | ((rPMC.h >> 4) & 0xf);
return ((rPMC.l << 4) & 0xfff0) | ((rPMC.l >> 4) & 0xf);
} else {
ssp->emu_status |= SSP_PMC_HAVE_ADDR;
//return rPMC.h;
return rPMC.l;
}
}
static void write_PMC(u32 d)
{
if (ssp->emu_status & SSP_PMC_HAVE_ADDR) {
//if (ssp->emu_status & SSP_PMC_SET)
// elprintf(EL_ANOMALY|EL_SVP, "prev PMC not used @ %04x", GET_PPC_OFFS());
ssp->emu_status |= SSP_PMC_SET;
ssp->emu_status &= ~SSP_PMC_HAVE_ADDR;
//rPMC.l = d;
rPMC.h = d;
#ifdef LOG_SVP
elprintf(EL_SVP, "PMC w m %04x @ %04x", rPMC.l, GET_PPC_OFFS());
#endif
} else {
ssp->emu_status |= SSP_PMC_HAVE_ADDR;
//rPMC.h = d;
rPMC.l = d;
#ifdef LOG_SVP
elprintf(EL_SVP, "PMC w a %04x @ %04x", rPMC.h, GET_PPC_OFFS());
#endif
}
}
// 15
static u32 read_AL(void)
{
if (*(PC-1) == 0x000f) {
#ifdef LOG_SVP
elprintf(EL_SVP, "ssp dummy PM assign %08x @ %04x", rPMC.v, GET_PPC_OFFS());
#endif
ssp->emu_status &= ~(SSP_PMC_SET|SSP_PMC_HAVE_ADDR); // ?
}
return rAL;
}
static void write_AL(u32 d)
{
rAL = d;
}
typedef u32 (*read_func_t)(void);
typedef void (*write_func_t)(u32 d);
static read_func_t read_handlers[16] =
{
read_unknown, read_unknown, read_unknown, read_unknown, // -, X, Y, A
read_unknown, // 4 ST
read_STACK,
read_PC,
read_P,
read_PM0, // 8
read_PM1,
read_PM2,
read_XST,
read_PM4, // 12
read_unknown, // 13 gr13
read_PMC,
read_AL
};
static write_func_t write_handlers[16] =
{
write_unknown, write_unknown, write_unknown, write_unknown, // -, X, Y, A
// write_unknown, // 4 ST
write_ST, // 4 ST (debug hook)
write_STACK,
write_PC,
write_unknown, // 7 P
write_PM0, // 8
write_PM1,
write_PM2,
write_XST,
write_PM4, // 12
write_unknown, // 13 gr13
write_PMC,
write_AL
};
// -----------------------------------------------------
// pointer register handlers
//
#define ptr1_read(op) ptr1_read_(op&3,(op>>6)&4,(op<<1)&0x18)
static u32 ptr1_read_(int ri, int isj2, int modi3)
{
//int t = (op&3) | ((op>>6)&4) | ((op<<1)&0x18);
u32 mask, add = 0, t = ri | isj2 | modi3;
unsigned char *rp = NULL;
switch (t)
{
// mod=0 (00)
case 0x00:
case 0x01:
case 0x02: return ssp->RAM0[ssp->r0[t&3]];
case 0x03: return ssp->RAM0[0];
case 0x04:
case 0x05:
case 0x06: return ssp->RAM1[ssp->r1[t&3]];
case 0x07: return ssp->RAM1[0];
// mod=1 (01), "+!"
case 0x08:
case 0x09:
case 0x0a: return ssp->RAM0[ssp->r0[t&3]++];
case 0x0b: return ssp->RAM0[1];
case 0x0c:
case 0x0d:
case 0x0e: return ssp->RAM1[ssp->r1[t&3]++];
case 0x0f: return ssp->RAM1[1];
// mod=2 (10), "-"
case 0x10:
case 0x11:
case 0x12: rp = &ssp->r0[t&3]; t = ssp->RAM0[*rp];
if (!(rST&7)) { (*rp)--; return t; }
add = -1; goto modulo;
case 0x13: return ssp->RAM0[2];
case 0x14:
case 0x15:
case 0x16: rp = &ssp->r1[t&3]; t = ssp->RAM1[*rp];
if (!(rST&7)) { (*rp)--; return t; }
add = -1; goto modulo;
case 0x17: return ssp->RAM1[2];
// mod=3 (11), "+"
case 0x18:
case 0x19:
case 0x1a: rp = &ssp->r0[t&3]; t = ssp->RAM0[*rp];
if (!(rST&7)) { (*rp)++; return t; }
add = 1; goto modulo;
case 0x1b: return ssp->RAM0[3];
case 0x1c:
case 0x1d:
case 0x1e: rp = &ssp->r1[t&3]; t = ssp->RAM1[*rp];
if (!(rST&7)) { (*rp)++; return t; }
add = 1; goto modulo;
case 0x1f: return ssp->RAM1[3];
}
return 0;
modulo:
mask = (1 << (rST&7)) - 1;
*rp = (*rp & ~mask) | ((*rp + add) & mask);
return t;
}
static void ptr1_write(int op, u32 d)
{
int t = (op&3) | ((op>>6)&4) | ((op<<1)&0x18);
switch (t)
{
// mod=0 (00)
case 0x00:
case 0x01:
case 0x02: ssp->RAM0[ssp->r0[t&3]] = d; return;
case 0x03: ssp->RAM0[0] = d; return;
case 0x04:
case 0x05:
case 0x06: ssp->RAM1[ssp->r1[t&3]] = d; return;
case 0x07: ssp->RAM1[0] = d; return;
// mod=1 (01), "+!"
// mod=3, "+"
case 0x08:
case 0x18:
case 0x09:
case 0x19:
case 0x0a:
case 0x1a: ssp->RAM0[ssp->r0[t&3]++] = d; return;
case 0x0b: ssp->RAM0[1] = d; return;
case 0x0c:
case 0x1c:
case 0x0d:
case 0x1d:
case 0x0e:
case 0x1e: ssp->RAM1[ssp->r1[t&3]++] = d; return;
case 0x0f: ssp->RAM1[1] = d; return;
// mod=2 (10), "-"
case 0x10:
case 0x11:
case 0x12: ssp->RAM0[ssp->r0[t&3]--] = d; return;
case 0x13: ssp->RAM0[2] = d; return;
case 0x14:
case 0x15:
case 0x16: ssp->RAM1[ssp->r1[t&3]--] = d; return;
case 0x17: ssp->RAM1[2] = d; return;
// mod=3 (11)
case 0x1b: ssp->RAM0[3] = d; return;
case 0x1f: ssp->RAM1[3] = d; return;
}
}
static u32 ptr2_read(int op)
{
int mv = 0, t = (op&3) | ((op>>6)&4) | ((op<<1)&0x18);
switch (t)
{
// mod=0 (00)
case 0x00:
case 0x01:
case 0x02: mv = ssp->RAM0[ssp->r0[t&3]]++; break;
case 0x03: mv = ssp->RAM0[0]++; break;
case 0x04:
case 0x05:
case 0x06: mv = ssp->RAM1[ssp->r1[t&3]]++; break;
case 0x07: mv = ssp->RAM1[0]++; break;
// mod=1 (01)
case 0x0b: mv = ssp->RAM0[1]++; break;
case 0x0f: mv = ssp->RAM1[1]++; break;
// mod=2 (10)
case 0x13: mv = ssp->RAM0[2]++; break;
case 0x17: mv = ssp->RAM1[2]++; break;
// mod=3 (11)
case 0x1b: mv = ssp->RAM0[3]++; break;
case 0x1f: mv = ssp->RAM1[3]++; break;
default: elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: invalid mod in ((rX))? @ %04x", GET_PPC_OFFS());
return 0;
}
return ((unsigned short *)svp->iram_rom)[mv];
}
// -----------------------------------------------------
void ssp1601_reset(ssp1601_t *l_ssp)
{
ssp = l_ssp;
ssp->emu_status = 0;
ssp->gr[SSP_GR0].v = 0xffff0000;
rPC = 0x400;
rSTACK = 0; // ? using ascending stack
rST = 0;
}
#ifdef USE_DEBUGGER
static void debug_dump(void)
{
printf("GR0: %04x X: %04x Y: %04x A: %08x\n", ssp->gr[SSP_GR0].h, rX, rY, ssp->gr[SSP_A].v);
printf("PC: %04x (%04x) P: %08x\n", GET_PC(), GET_PC() << 1, ssp->gr[SSP_P].v);
printf("PM0: %04x PM1: %04x PM2: %04x\n", rPM0, rPM1, rPM2);
printf("XST: %04x PM4: %04x PMC: %08x\n", rXST, rPM4, ssp->gr[SSP_PMC].v);
printf(" ST: %04x %c%c%c%c, GP0_0 %i, GP0_1 %i\n", rST, rST&SSP_FLAG_N?'N':'n', rST&SSP_FLAG_V?'V':'v',
rST&SSP_FLAG_Z?'Z':'z', rST&SSP_FLAG_L?'L':'l', (rST>>5)&1, (rST>>6)&1);
printf("STACK: %i %04x %04x %04x %04x %04x %04x\n", rSTACK, ssp->stack[0], ssp->stack[1],
ssp->stack[2], ssp->stack[3], ssp->stack[4], ssp->stack[5]);
printf("r0-r2: %02x %02x %02x r4-r6: %02x %02x %02x\n", rIJ[0], rIJ[1], rIJ[2], rIJ[4], rIJ[5], rIJ[6]);
elprintf(EL_SVP, "cycles: %i, emu_status: %x", g_cycles, ssp->emu_status);
}
static void debug_dump_mem(void)
{
int h, i;
printf("RAM0\n");
for (h = 0; h < 32; h++)
{
if (h == 16) printf("RAM1\n");
printf("%03x:", h*16);
for (i = 0; i < 16; i++)
printf(" %04x", ssp->RAM[h*16+i]);
printf("\n");
}
}
static void debug_dump2file(const char *fname, void *mem, int len)
{
FILE *f = fopen(fname, "wb");
unsigned short *p = mem;
int i;
if (f) {
for (i = 0; i < len/2; i++) p[i] = (p[i]<<8) | (p[i]>>8);
fwrite(mem, 1, len, f);
fclose(f);
for (i = 0; i < len/2; i++) p[i] = (p[i]<<8) | (p[i]>>8);
printf("dumped to %s\n", fname);
}
else
printf("dump failed\n");
}
static int bpts[10] = { 0, };
static void debug(unsigned int pc, unsigned int op)
{
static char buffo[64] = {0,};
char buff[64] = {0,};
int i;
if (running) {
for (i = 0; i < 10; i++)
if (pc != 0 && bpts[i] == pc) {
printf("breakpoint %i\n", i);
running = 0;
break;
}
}
if (running) return;
printf("%04x (%02x) @ %04x\n", op, op >> 9, pc<<1);
while (1)
{
printf("dbg> ");
fflush(stdout);
fgets(buff, sizeof(buff), stdin);
if (buff[0] == '\n') strcpy(buff, buffo);
else strcpy(buffo, buff);
switch (buff[0]) {
case 0: exit(0);
case 'c':
case 'r': running = 1; return;
case 's':
case 'n': return;
case 'x': debug_dump(); break;
case 'm': debug_dump_mem(); break;
case 'b': {
char *baddr = buff + 2;
i = 0;
if (buff[3] == ' ') { i = buff[2] - '0'; baddr = buff + 4; }
bpts[i] = strtol(baddr, NULL, 16) >> 1;
printf("breakpoint %i set @ %04x\n", i, bpts[i]<<1);
break;
}
case 'd':
sprintf(buff, "iramrom_%04x.bin", last_iram);
debug_dump2file(buff, svp->iram_rom, sizeof(svp->iram_rom));
debug_dump2file("dram.bin", svp->dram, sizeof(svp->dram));
break;
default: printf("unknown command\n"); break;
}
}
}
#endif // USE_DEBUGGER
void ssp1601_run(int cycles)
{
SET_PC(rPC);
g_cycles = cycles;
while (g_cycles > 0 && !(ssp->emu_status & SSP_WAIT_MASK))
{
int op;
u32 tmpv;
op = *PC++;
#ifdef USE_DEBUGGER
debug(GET_PC()-1, op);
#endif
switch (op >> 9)
{
// ld d, s
case 0x00:
if (op == 0) break; // nop
if (op == ((SSP_A<<4)|SSP_P)) { // A <- P
// not sure. MAME claims that only hi word is transfered.
read_P(); // update P
rA32 = rP.v;
}
else
{
tmpv = REG_READ(op & 0x0f);
REG_WRITE((op & 0xf0) >> 4, tmpv);
}
break;
// ld d, (ri)
case 0x01: tmpv = ptr1_read(op); REG_WRITE((op & 0xf0) >> 4, tmpv); break;
// ld (ri), s
case 0x02: tmpv = REG_READ((op & 0xf0) >> 4); ptr1_write(op, tmpv); break;
// ldi d, imm
case 0x04: tmpv = *PC++; REG_WRITE((op & 0xf0) >> 4, tmpv); break;
// ld d, ((ri))
case 0x05: tmpv = ptr2_read(op); REG_WRITE((op & 0xf0) >> 4, tmpv); break;
// ldi (ri), imm
case 0x06: tmpv = *PC++; ptr1_write(op, tmpv); break;
// ld adr, a
case 0x07: ssp->RAM[op & 0x1ff] = rA; break;
// ld d, ri
case 0x09: tmpv = rIJ[(op&3)|((op>>6)&4)]; REG_WRITE((op & 0xf0) >> 4, tmpv); break;
// ld ri, s
case 0x0a: rIJ[(op&3)|((op>>6)&4)] = REG_READ((op & 0xf0) >> 4); break;
// ldi ri, simm
case 0x0c:
case 0x0d:
case 0x0e:
case 0x0f: rIJ[(op>>8)&7] = op; break;
// call cond, addr
case 0x24: {
int cond = 0;
COND_CHECK
if (cond) { int new_PC = *PC++; write_STACK(GET_PC()); write_PC(new_PC); }
else PC++;
break;
}
// ld d, (a)
case 0x25: tmpv = ((unsigned short *)svp->iram_rom)[rA]; REG_WRITE((op & 0xf0) >> 4, tmpv); break;
// bra cond, addr
case 0x26: {
int cond = 0;
COND_CHECK
if (cond) { int new_PC = *PC++; write_PC(new_PC); }
else PC++;
break;
}
// mod cond, op
case 0x48: {
int cond = 0;
COND_CHECK
if (cond) {
switch (op & 7) {
case 2: rA32 = (signed int)rA32 >> 1; break; // shr (arithmetic)
case 3: rA32 <<= 1; break; // shl
case 6: rA32 = -(signed int)rA32; break; // neg
case 7: if ((int)rA32 < 0) rA32 = -(signed int)rA32; break; // abs
default:
#ifdef LOG_SVP
elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: unhandled mod %i @ %04x",
op&7, GET_PPC_OFFS());
#endif
break;
}
UPD_ACC_ZN // ?
}
break;
}
// mpys?
case 0x1b:
#ifdef LOG_SVP
if (!(op&0x100)) elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: no b bit @ %04x", GET_PPC_OFFS());
#endif
read_P(); // update P
rA32 -= rP.v; // maybe only upper word?
UPD_ACC_ZN // there checking flags after this
rX = ptr1_read_(op&3, 0, (op<<1)&0x18); // ri (maybe rj?)
rY = ptr1_read_((op>>4)&3, 4, (op>>3)&0x18); // rj
break;
// mpya (rj), (ri), b
case 0x4b:
#ifdef LOG_SVP
if (!(op&0x100)) elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: no b bit @ %04x", GET_PPC_OFFS());
#endif
read_P(); // update P
rA32 += rP.v; // confirmed to be 32bit
UPD_ACC_ZN // ?
rX = ptr1_read_(op&3, 0, (op<<1)&0x18); // ri (maybe rj?)
rY = ptr1_read_((op>>4)&3, 4, (op>>3)&0x18); // rj
break;
// mld (rj), (ri), b
case 0x5b:
#ifdef LOG_SVP
if (!(op&0x100)) elprintf(EL_SVP|EL_ANOMALY, "ssp FIXME: no b bit @ %04x", GET_PPC_OFFS());
#endif
rA32 = 0;
rST &= 0x0fff; // ?
rX = ptr1_read_(op&3, 0, (op<<1)&0x18); // ri (maybe rj?)
rY = ptr1_read_((op>>4)&3, 4, (op>>3)&0x18); // rj
break;
// OP a, s
case 0x10: OP_CHECK32(OP_SUBA32); tmpv = REG_READ(op & 0x0f); OP_SUBA(tmpv); break;
case 0x30: OP_CHECK32(OP_CMPA32); tmpv = REG_READ(op & 0x0f); OP_CMPA(tmpv); break;
case 0x40: OP_CHECK32(OP_ADDA32); tmpv = REG_READ(op & 0x0f); OP_ADDA(tmpv); break;
case 0x50: OP_CHECK32(OP_ANDA32); tmpv = REG_READ(op & 0x0f); OP_ANDA(tmpv); break;
case 0x60: OP_CHECK32(OP_ORA32 ); tmpv = REG_READ(op & 0x0f); OP_ORA (tmpv); break;
case 0x70: OP_CHECK32(OP_EORA32); tmpv = REG_READ(op & 0x0f); OP_EORA(tmpv); break;
// OP a, (ri)
case 0x11: tmpv = ptr1_read(op); OP_SUBA(tmpv); break;
case 0x31: tmpv = ptr1_read(op); OP_CMPA(tmpv); break;
case 0x41: tmpv = ptr1_read(op); OP_ADDA(tmpv); break;
case 0x51: tmpv = ptr1_read(op); OP_ANDA(tmpv); break;
case 0x61: tmpv = ptr1_read(op); OP_ORA (tmpv); break;
case 0x71: tmpv = ptr1_read(op); OP_EORA(tmpv); break;
// OP a, adr
case 0x03: tmpv = ssp->RAM[op & 0x1ff]; OP_LDA (tmpv); break;
case 0x13: tmpv = ssp->RAM[op & 0x1ff]; OP_SUBA(tmpv); break;
case 0x33: tmpv = ssp->RAM[op & 0x1ff]; OP_CMPA(tmpv); break;
case 0x43: tmpv = ssp->RAM[op & 0x1ff]; OP_ADDA(tmpv); break;
case 0x53: tmpv = ssp->RAM[op & 0x1ff]; OP_ANDA(tmpv); break;
case 0x63: tmpv = ssp->RAM[op & 0x1ff]; OP_ORA (tmpv); break;
case 0x73: tmpv = ssp->RAM[op & 0x1ff]; OP_EORA(tmpv); break;
// OP a, imm
case 0x14: tmpv = *PC++; OP_SUBA(tmpv); break;
case 0x34: tmpv = *PC++; OP_CMPA(tmpv); break;
case 0x44: tmpv = *PC++; OP_ADDA(tmpv); break;
case 0x54: tmpv = *PC++; OP_ANDA(tmpv); break;
case 0x64: tmpv = *PC++; OP_ORA (tmpv); break;
case 0x74: tmpv = *PC++; OP_EORA(tmpv); break;
// OP a, ((ri))
case 0x15: tmpv = ptr2_read(op); OP_SUBA(tmpv); break;
case 0x35: tmpv = ptr2_read(op); OP_CMPA(tmpv); break;
case 0x45: tmpv = ptr2_read(op); OP_ADDA(tmpv); break;
case 0x55: tmpv = ptr2_read(op); OP_ANDA(tmpv); break;
case 0x65: tmpv = ptr2_read(op); OP_ORA (tmpv); break;
case 0x75: tmpv = ptr2_read(op); OP_EORA(tmpv); break;
// OP a, ri
case 0x19: tmpv = rIJ[IJind]; OP_SUBA(tmpv); break;
case 0x39: tmpv = rIJ[IJind]; OP_CMPA(tmpv); break;
case 0x49: tmpv = rIJ[IJind]; OP_ADDA(tmpv); break;
case 0x59: tmpv = rIJ[IJind]; OP_ANDA(tmpv); break;
case 0x69: tmpv = rIJ[IJind]; OP_ORA (tmpv); break;
case 0x79: tmpv = rIJ[IJind]; OP_EORA(tmpv); break;
// OP simm
case 0x1c:
OP_SUBA(op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
case 0x3c:
OP_CMPA(op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
case 0x4c:
OP_ADDA(op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
// MAME code only does LSB of top word, but this looks wrong to me.
case 0x5c:
OP_ANDA(op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
case 0x6c:
OP_ORA (op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
case 0x7c:
OP_EORA(op & 0xff);
#ifdef LOG_SVP
if (op&0x100) elprintf(EL_SVP|EL_ANOMALY, "FIXME: simm with upper bit set");
#endif
break;
default:
#ifdef LOG_SVP
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME unhandled op %04x @ %04x", op, GET_PPC_OFFS());
#endif
break;
}
g_cycles--;
}
read_P(); // update P
rPC = GET_PC();
#ifdef LOG_SVP
if (ssp->gr[SSP_GR0].v != 0xffff0000)
elprintf(EL_ANOMALY|EL_SVP, "ssp FIXME: REG 0 corruption! %08x", ssp->gr[SSP_GR0].v);
#endif
}
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