Sysreg (0xBC100000) gets the ME's reset bit (0x4C bit 2), the soft
interrupt (0x44, which interrupts the other CPU: the ME's controller from
the main CPU, PSP_MECODEC_INTR from the ME), the hardware mutex (0x48,
each CPU sets its own bit only while the other's is clear) and the clock
and config registers it writes. The ME's interrupt controller (0xBC300000,
write-1-to-clear, mask at 8) answers the ME only. All of it is the ME's
state and stays unhandled without an ME.
On the ME: interrupts to EBase with EPC and EXL, halt sleeping until an
unmasked interrupt, and Count, which doesn't run: it stays 0 across 10ms
with ERL set after reset and with Status cleared, and reads back what was
written. Reset keeps the GPRs and sets Status ERL/BEV/SR, which homebrew
relies on: mcidclan's samples run C on the stack Sony's ME code left. The
values are from a kernel probe on a PSP-1000 (sp 0x801FFFE0, COP0 22 = 1,
Status 0x20500404, mfic 0, which doesn't gate interrupts).
The main CPU runs base interrupt handlers the way interruptman calls them
(a0 intno, a1 arg, a2 interrupted pc; -2 disables), and interrupt 31 has
a stand-in for me_wrapper's handler, which homebrew releases first.
While the ME is emulated, any main CPU code may access hardware registers:
homebrew calls its own code in kernel mode through a kcall module. This
is a stopgap (g_kernelModeAnywhere, marked HACK): kernel mode should be
part of the CPU's state, switched on while a kernel module's export runs.
The memcpy/memmove replacements copy through MMIO when an end is a
register address, for code copied to the boot page.
mcidclan's me-soft-interrupt sample now runs, counting each interrupt in
both directions.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
HLEFunc and ReplaceFunc now take the MIPSState they run on. The dispatch
paths (both interpreters and every JIT backend) pass in the state they
belong to, and CallSyscall*, hleFinishSyscall and the HLE mips call
machinery use it instead of currentMIPS.
The wrappers in FunctionWrappers.h take the function as `auto` and call it
through HLECall, which also accepts an implementation with an extra leading
MIPSState * parameter and passes the state to it. Any other signature still
fails to compile, as before. PARAM/RETURN now refer to a local `mips`.
The HLE functions (and replacement functions) that used currentMIPS now take
the state that way. Callers outside a syscall's own frame - CoreTiming
events, the adhoc matching thread, dialogs, PPGe, the debugger UIs - pass
currentMIPS or &mipsr4k explicitly. The kernel's thread internals still use
currentMIPS.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
sceKernelRegisterIntrHandler, sceKernelReleaseIntrHandler,
sceKernelEnableIntr and sceKernelDisableIntr now keep a base handler per
interrupt, and return what tests/intr/kernel/intrhandler recorded on a PSP:
80020065 for an interrupt number out of range (or no handler), 80020067 for
a second handler, 80020068 for one that isn't there.
Faking success for these used to stall the VSH boot, which is why they were
left unresolved. It doesn't anymore: the firmware's drivers make the same 31
calls (interrupts 4, 12, 15-18, 20-24 and 31), and 6.61 reaches the XMB on the
JIT and the interpreter. Nothing raises those interrupts yet, so the handlers
are only kept, and saved in savestates (IntrHandler section version 2).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
An interrupt with no handler to run, a vblank with none registered for
example, switched the running thread off to idle and left it there until
some later event rescheduled: ~775us of every frame in a game that spins
without a vblank handler. It now reschedules at once. Taking an interrupt
also clears the ll bit directly, which that switch had been doing.
Interrupt handlers can now carry a cost before they run and after the
last queued one returns. Alarms use it: on hardware a thread that keeps
running loses ~70us to an alarm handler, and a thread the handler wakes
runs ~50us after it (pspautotests threads/scheduling/alarmcosts), so
17us in and 40us out. sceKernelSetAlarm's 40us is split evenly around the
deadline, keeping the handler ~1040us after a 1000us alarm.
A handler's return value re-arms its alarm counting from the previous
deadline, so a repeating alarm doesn't drift by those costs, unless
that's already past, as after interrupts were suspended for a while.
The vblank's own cost (~62us of CPU on hardware) isn't charged yet: with
it, a waiter ~90us after the vblank still reads hcount 1 on hardware, but
line 2 here. Hardware evidently raises the interrupt ~40us before the
line count wraps. That's noted where the waiters are released.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Reinitialize() wiped the 64 display lists but kept the queue of their ids.
Whatever the old executable still had queued came back as lists with no state
and a pc of 0, behind the first list of the new executable, where they
blocked everything. Crazy Taxi: Fare Wars is a launcher for its two games,
and stopped at a black screen that way. Fixes#19894.
This removes the workaround for it, which dropped such a list but returned
before currentList was cleared, and only worked as long as something else
happened to clear it later. A list with a bad pc is now dropped like one that
ran into an error, instead of sitting at the head of the queue for good.
Also narrows what sceGeBreak(1) throws away to interrupts that have actually
been raised, which is what gpu/ge/intrsuspend shows. The ones we haven't
raised yet are only late because we execute lists ahead of time: a game that
breaks right after its last list, and then waits for what the finish callback
signals, got that callback long ago on hardware.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
This is a bit strange, but tests seem to suggest this is correct.
A worse priority thread won't run before savedata shutdown hits 0, but the
thread that initiated shutdown runs before shutdown completes.
Fixes Freakout Extreme Freeride loading savedata.
Based on tests, vblank doesn't queue up (makes sense) while
interrupts are disabled.
I'm not 100% sure about the GPU stuff but it seems to only come
from HLE via sceGe, so this should fix those return values.
