From ba6e8bfd4b707aab042e47bc3e2a14f70be01075 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Wed, 28 Aug 2013 03:07:33 +0300
Subject: [PATCH] cd: clean up dmna handling, stuff
---
pico/cd/mcd.c | 17 +++++++++--
pico/cd/memory.c | 73 +++++++++++++++++++++++++-----------------------
pico/pico_int.h | 2 +-
3 files changed, 54 insertions(+), 38 deletions(-)
diff --git a/pico/cd/mcd.c b/pico/cd/mcd.c
index 539d157e..82ae1bc6 100644
--- a/pico/cd/mcd.c
+++ b/pico/cd/mcd.c
@@ -252,15 +252,18 @@ int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
#undef now
}
+#define pcd_run_cpus_normal pcd_run_cpus
+//#define pcd_run_cpus_lockstep pcd_run_cpus
+
static void SekSyncM68k(void);
-static void pcd_run_cpus(int m68k_cycles)
+static inline void pcd_run_cpus_normal(int m68k_cycles)
{
SekCycleAim += m68k_cycles;
if (Pico_mcd->m.m68k_poll_cnt >= 16 && !SekShouldInterrupt()) {
int s68k_left = pcd_sync_s68k(SekCycleAim, 1);
if (s68k_left <= 0) {
- elprintf(EL_CDPOLL, "m68k poll [%02x] %d @%06x",
+ elprintf(EL_CDPOLL, "m68k poll [%02x] x%d @%06x",
Pico_mcd->m.m68k_poll_a, Pico_mcd->m.m68k_poll_cnt, SekPc);
SekCycleCnt = SekCycleAim;
return;
@@ -271,6 +274,16 @@ static void pcd_run_cpus(int m68k_cycles)
SekSyncM68k();
}
+static inline void pcd_run_cpus_lockstep(int m68k_cycles)
+{
+ unsigned int target = SekCycleAim + m68k_cycles;
+ do {
+ SekCycleAim += 8;
+ SekSyncM68k();
+ pcd_sync_s68k(SekCycleAim, 0);
+ } while (CYCLES_GT(target, SekCycleAim));
+}
+
#define PICO_CD
#define CPUS_RUN(m68k_cycles) \
pcd_run_cpus(m68k_cycles)
diff --git a/pico/cd/memory.c b/pico/cd/memory.c
index 82e6d6dd..f8ffaeb0 100644
--- a/pico/cd/memory.c
+++ b/pico/cd/memory.c
@@ -184,24 +184,24 @@ void m68k_reg_write8(u32 a, u32 d)
case 3:
dold = Pico_mcd->s68k_regs[3];
elprintf(EL_CDREG3, "m68k_regs w3: %02x @%06x", (u8)d, SekPc);
- //if ((Pico_mcd->s68k_regs[3]&4) != (d&4)) dprintf("m68k: ram mode %i mbit", (d&4) ? 1 : 2);
- //if ((Pico_mcd->s68k_regs[3]&2) != (d&2)) dprintf("m68k: %s", (d&4) ? ((d&2) ? "word swap req" : "noop?") :
- // ((d&2) ? "word ram to s68k" : "word ram to m68k"));
- if (dold & 4) { // 1M mode
- d ^= 2; // writing 0 to DMNA actually sets it, 1 does nothing
- } else {
- if ((d ^ dold) & d & 2) { // DMNA is being set
- dold &= ~1; // return word RAM to s68k
- /* Silpheed hack: bset(w3), r3, btst, bne, r3 */
- SekEndRun(20+16+10+12+16);
- }
- }
- d = (d & 0xc2) | (dold & 0x1f);
if ((d ^ dold) & 0xc0) {
elprintf(EL_CDREGS, "m68k: prg bank: %i -> %i",
(Pico_mcd->s68k_regs[a]>>6), ((d>>6)&3));
remap_prg_window(d);
}
+
+ // 2M mode state is tracked regardless of current mode
+ if (d & 2) {
+ Pico_mcd->m.dmna_ret_2m |= 2;
+ Pico_mcd->m.dmna_ret_2m &= ~1;
+ }
+ if (dold & 4) { // 1M mode
+ d ^= 2; // 0 sets DMNA, 1 does nothing
+ d = (d & 0xc2) | (dold & 0x1f);
+ }
+ else
+ d = (d & 0xc0) | (dold & 0x1c) | Pico_mcd->m.dmna_ret_2m;
+
goto write_comm;
case 6:
Pico_mcd->bios[0x72 + 1] = d; // simple hint vector changer
@@ -343,35 +343,34 @@ void s68k_reg_write8(u32 a, u32 d)
elprintf(EL_CDREG3, "s68k_regs w3: %02x @%06x", (u8)d, SekPcS68k);
d &= 0x1d;
d |= dold & 0xc2;
+
+ // 2M mode state
+ if (d & 1) {
+ Pico_mcd->m.dmna_ret_2m |= 1;
+ Pico_mcd->m.dmna_ret_2m &= ~2; // DMNA clears
+ }
+
if (d & 4)
{
- if ((d ^ dold) & 0x1d) {
- d &= ~2; // in case of mode or bank change we clear DMNA (m68k req) bit
- remap_word_ram(d);
- }
if (!(dold & 4)) {
elprintf(EL_CDREG3, "wram mode 2M->1M");
wram_2M_to_1M(Pico_mcd->word_ram2M);
}
+
+ if ((d ^ dold) & 0x1d)
+ remap_word_ram(d);
+
+ if ((d ^ dold) & 0x05)
+ d &= ~2; // clear DMNA - swap complete
}
else
{
if (dold & 4) {
elprintf(EL_CDREG3, "wram mode 1M->2M");
- if (!(d&1)) { // it didn't set the ret bit, which means it doesn't want to give WRAM to m68k
- d &= ~3;
- d |= (dold&1) ? 2 : 1; // then give it to the one which had bank0 in 1M mode
- }
wram_1M_to_2M(Pico_mcd->word_ram2M);
remap_word_ram(d);
}
- // s68k can only set RET, writing 0 has no effect
- else if ((dold ^ d) & d & 1) { // RET being set
- SekEndRunS68k(20+16+10+12+16); // see DMNA case
- } else
- d |= dold & 1;
- if (d & 1)
- d &= ~2; // DMNA clears
+ d = (d & ~3) | Pico_mcd->m.dmna_ret_2m;
}
goto write_comm;
}
@@ -806,20 +805,22 @@ static u32 PicoReadS68k8_pr(u32 a)
// regs
if ((a & 0xfe00) == 0x8000) {
a &= 0x1ff;
- elprintf(EL_CDREGS, "s68k_regs r8: [%02x] @ %06x", a, SekPcS68k);
if (a >= 0x0e && a < 0x30) {
d = Pico_mcd->s68k_regs[a];
s68k_poll_detect(a, d);
- elprintf(EL_CDREGS, "ret = %02x", (u8)d);
- return d;
+ goto regs_done;
}
else if (a >= 0x58 && a < 0x68)
d = gfx_cd_read(a & ~1);
else d = s68k_reg_read16(a & ~1);
if (!(a & 1))
d >>= 8;
- elprintf(EL_CDREGS, "ret = %02x", (u8)d);
- return d & 0xff;
+
+regs_done:
+ d &= 0xff;
+ elprintf(EL_CDREGS, "s68k_regs r8: [%02x] %02x @ %06x",
+ a, d, SekPcS68k);
+ return d;
}
// PCM
@@ -847,11 +848,12 @@ static u32 PicoReadS68k16_pr(u32 a)
// regs
if ((a & 0xfe00) == 0x8000) {
a &= 0x1fe;
- elprintf(EL_CDREGS, "s68k_regs r16: [%02x] @ %06x", a, SekPcS68k);
if (0x58 <= a && a < 0x68)
d = gfx_cd_read(a);
else d = s68k_reg_read16(a);
- elprintf(EL_CDREGS, "ret = %04x", d);
+
+ elprintf(EL_CDREGS, "s68k_regs r16: [%02x] %04x @ %06x",
+ a, d, SekPcS68k);
return d;
}
@@ -1024,6 +1026,7 @@ void pcd_state_loaded_mem(void)
wram_2M_to_1M(Pico_mcd->word_ram2M);
remap_word_ram(r3);
remap_prg_window(r3);
+ Pico_mcd->m.dmna_ret_2m &= 3;
// restore hint vector
*(unsigned short *)(Pico_mcd->bios + 0x72) = Pico_mcd->m.hint_vector;
diff --git a/pico/pico_int.h b/pico/pico_int.h
index be56abd0..2053ac60 100644
--- a/pico/pico_int.h
+++ b/pico/pico_int.h
@@ -395,7 +395,7 @@ struct mcd_misc
unsigned short s68k_poll_cnt;
unsigned int s68k_poll_clk;
unsigned char bcram_reg; // 18: battery-backed RAM cart register
- unsigned char pad2;
+ unsigned char dmna_ret_2m;
unsigned short pad3;
int pad4[9];
};
--
2.39.5