Commit Graph

14 Commits

Author SHA1 Message Date
David Guillen Fandos c0d8ffaa38 Adding DMA transfer "Sleep" mode
This accounts for DMA stealing cycles from the CPU whenever the CPU
triggers a DMA (does not affect H/V blank or sound DMAs).
Works by moving the CPU to a PAUSED state where the cycles are accounted
for, reusing a similar mechanism for HALT/STOP.

Fixes a couple of games, notably GTA that has a DMA/IRQ race condition
(likely a bug really) if cycles are grossly miscalculated.
2023-09-08 19:44:13 +02:00
David Guillen Fandos 1d1c719372 Remove COMPLETED_FRAME flag to simplify things 2023-09-06 00:48:37 +02:00
David Guillen Fandos 5f3e0a88cf Remove alert_loop in favour of cpu_sleep_loop 2023-09-06 00:02:47 +02:00
David Guillen Fandos 8ae2234374 Fix delay slot issue on PSP/PS2 2023-09-04 23:44:28 +02:00
David Guillen Fandos 872a22ae51 [mips] Correct GP restore to a more accurate location 2023-04-24 20:52:14 +02:00
David Guillen Fandos eb50c15b1c Remove CHANGED_PC_STATUS, simplify update flow 2023-04-24 20:24:03 +02:00
David Guillen Fandos 11d87b89df Rewrite I/O side effects write and IRQ triggers
This rewrites the way that CPU alerts work, making them a bitmap (since
multiple alerts can happen simultaneously, like SMC and IRQ). This
doesn't really fix many games but improves accuracy overall and improves
performance on some I/O writes (the ones without side effects).
The IRQ raising is now decoupled and explicitely called via a new
function (check_and_raise_interrupts) to avoid issues such as invalid
CPSR values (doesn't seem to bother most games!). There's more side
effects missing, so this just lays the ground for more fixes.
2023-04-14 01:41:55 +02:00
David Guillen Fandos 4f3c9a5e58 [all] Fix CPSR and CPU modes
gpsp doesn't differentiate between USER and SYSTEM mode, most likely
cause it is not that important for most games. This implements the modes
correctly and adds checks for privileged operations. Still some
bugs/hacks but it mostly fixes CPSR/SPSR reads/writes.

To implement PSR writes we are using a more refined masks and force mode
bit num. 4 to always be one. Reserved bits are forced to zero (this
needs to be validated on a real device).
2023-01-11 21:26:32 +01:00
David Guillen Fandos b552d5eb7e Improve open bus reads on ARM/MIPS 2023-01-05 21:29:20 +01:00
David Guillen Fandos ef399b9315 [mips] Remove IWRAM stack optimization hack
Converted the hack into another... hopefully better hack.
Check for IW/EWRAM addr bit and handle accesses to EWRAM by correcting
the base addr and the mirroring range.
Assumes that iwram and ewram buffers are at a distance multiple of 64KB
for speed (so that lw/sw offsets can be shared).

This fixes a variety of games that should have been present in
game_config.txt such as Ninja Cop, Star Wars JPB, Medal of Honor,
Spongebob, etc. Some of them were just missing regional versions of the
cart. It also fixes newer games and homebrew such as GoodBoy Galaxy.
2021-12-30 23:39:09 +01:00
David Guillen Fandos 3a6ca8d941 Better cycle accounting, taking remainders partially into account 2021-12-21 19:59:33 +01:00
David Guillen Fandos 31451d16ff [mips] Fix CPSR store bug during IRQ
Similarly to 61ef776, this fixes the bug for MIPS.
2021-12-10 19:28:06 +01:00
David Guillen Fandos 3a7fedb8fb Simplify MMAP machinery for Win/Lin/Mac/Android
This gets rid of the bloated memmap_win32.c in favour of a much simpler
wrapper. This will be needed in the future since the wrapper does not
support MAP_FIXED maps (necessary for some platforms)
2021-11-05 18:23:05 +01:00
David Guillen Fandos 15cc02e03c [MIPS] Move and restructure mips backend 2021-10-30 22:59:33 +02:00
Renamed from psp/mips_stub.S (Browse further)