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mcd, fixes for cycle accounting

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This commit is contained in:
kub 2020-11-18 23:59:29 +01:00
parent 69b7b2641b
commit 9f01ce95ae
1 changed files with 12 additions and 5 deletions
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17
pico/cd/mcd.c
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@ -12,6 +12,7 @@
extern unsigned char formatted_bram[4*0x10]; extern unsigned char formatted_bram[4*0x10];
static unsigned int mcd_m68k_cycle_mult; static unsigned int mcd_m68k_cycle_mult;
static unsigned int mcd_s68k_cycle_mult;
static unsigned int mcd_m68k_cycle_base; static unsigned int mcd_m68k_cycle_base;
static unsigned int mcd_s68k_cycle_base; static unsigned int mcd_s68k_cycle_base;
@ -138,16 +139,22 @@ static void SekRunS68k(unsigned int to)
#elif defined(EMU_F68K) #elif defined(EMU_F68K)
SekCycleCntS68k += fm68k_emulate(&PicoCpuFS68k, cyc_do, 0) - cyc_do; SekCycleCntS68k += fm68k_emulate(&PicoCpuFS68k, cyc_do, 0) - cyc_do;
#endif #endif
SekCyclesLeftS68k = 0;
pprof_end(s68k); pprof_end(s68k);
} }
static void pcd_set_cycle_mult(void) static void pcd_set_cycle_mult(void)
{ {
// ~1.63 for NTSC, ~1.645 for PAL unsigned int div;
if (Pico.m.pal) if (Pico.m.pal)
mcd_m68k_cycle_mult = ((12500000ull << 16) / (50*313*488)); div = 50*313*488;
else else
mcd_m68k_cycle_mult = ((12500000ull << 16) / (60*262*488)) + 1; div = 60*262*488;
// ~1.63 for NTSC, ~1.645 for PAL; round to nearest, x/y+0.5 -> (x+y/2)/y
mcd_m68k_cycle_mult = ((12500000ull << 16) + div/2) / div;
mcd_s68k_cycle_mult = ((1ull*div << 16) + 6250000) / 12500000;
} }
unsigned int pcd_cycles_m68k_to_s68k(unsigned int c) unsigned int pcd_cycles_m68k_to_s68k(unsigned int c)
@ -287,7 +294,7 @@ int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
if (Pico_mcd->m.busreq != 1) { /* busreq/reset */ if (Pico_mcd->m.busreq != 1) { /* busreq/reset */
SekCycleCntS68k = SekCycleAimS68k = s68k_target; SekCycleCntS68k = SekCycleAimS68k = s68k_target;
pcd_run_events(m68k_target); pcd_run_events(s68k_target);
return 0; return 0;
} }
@ -326,7 +333,7 @@ void pcd_run_cpus_normal(int m68k_cycles)
Pico.t.m68c_cnt = Pico.t.m68c_aim; Pico.t.m68c_cnt = Pico.t.m68c_aim;
return; return;
} }
Pico.t.m68c_cnt = Pico.t.m68c_aim - (s68k_left * 40220 >> 16); Pico.t.m68c_cnt = Pico.t.m68c_aim - (s68k_left * mcd_s68k_cycle_mult >> 16);
} }
while (CYCLES_GT(Pico.t.m68c_aim, Pico.t.m68c_cnt)) { while (CYCLES_GT(Pico.t.m68c_aim, Pico.t.m68c_cnt)) {