We currently have two different code paths for initializing controllers:
Either the frontend (DolphinQt) can do it, or if the frontend doesn't do
it, the core will do it automatically when booting. Having these two
paths has caused problems in the past due to only one frontend being
tested (see de7ef47548). I would like to get rid of the latter path to
avoid further problems like this.
This also changes the behavior for the invalid gamma value, which was confirmed to behave the same as 2.2.
Note that currently, the gamma value is only used for XFB copies, even though hardware testing indicates it also works for EFB copies. This will be changed in a later commit.
Before, Free Look would accept background input by default, which means it was easy to accidentally move the camera while typing in another window. (This is because HotkeyScheduler::Run sets the input gate to `true` after it's copied the hotkey state, supposedly for other threads (though `SetInputGate` uses a `thread_local` variable so I'm not 100% sure that's correct) and for the GBA windows (which always accept unfocused input, presumably because they won't be focused normally).
This should reduce (but not completely eliminate) gradual audio desyncs in dumps. This also allows for accurate sample rates for the GameCube.
Completely eliminating gradual audio desyncs will require resampling to an integer sample rate, as nothing seems to support a non-integer sample rate.
These values were obtained by setting a breakpoint at a game's entry point, and then observing the register values with Dolphin's register widget.
There are other registers that aren't handled by this PR, including CR, XER, SRR0, SRR1, and "Int Mask" (as well as most of the GPRs). They could be added in a later PR if it turns out that their values matter, but probably most of them don't.
This fixes Datel titles booting with the IPL skipped (see https://bugs.dolphin-emu.org/issues/8223), though when booted this way they are currently missing textures. Due to somewhat janky code, Datel overwrites the syscall interrupt handler and then immediately triggers it (with the `sc` instruction) before they restore the correct one. This works on real hardware due to icache, and also works in Dolphin when the IPL runs due to icache, but prior to this change `HID0.ICE` defaulted to 0 so icache was not enabled when the IPL was skipped.
DSPHLE::Initialize sets the halt and init bits to true (i.e. m_dsp_control.Hex starts as 0x804), which is reasonable behavior (this is the state the DSP will be in when starting a game from the IPL, as after `__OSStopAudioSystem` the control register is 0x804).
However, CMailHandler::m_halted defaults to false, and we only call CMailHandler::SetHalted in DSPHLE::DSP_WriteControlRegister when m_dsp_control.DSPHalt changes, so since DSPHalt defaults to true, if the first thing that happens is writing true to DSPHalt, we won't properly halt the mail handler.
Now, we call CMailHandler::SetHalted on startup. This fixes Datel titles when the IPL is skipped with DSP HLE (though this configuration only works once https://bugs.dolphin-emu.org/issues/8223 is fixed).
This fixes booting Datel titles with DSPHLE (see https://bugs.dolphin-emu.org/issues/12943). Datel messed up their DSP initialization code, so it only works by receiving a mail later on, but if halting isn't implemented then it receives the mail too early and hangs.
It's cleared whenever the uCode changes, so there's no reason to clear it in a destructor or during initialization.
I've also renamed it to ClearPending.
