SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Instead of constructing IPCCommandResult with static member functions
in the Device class, we can just add the relevant constructors to the
reply struct itself. Makes more sense than putting it in Device
when the struct is used in the kernel code and doesn't use any Device
specific members...
This commit also changes the IPC command handlers to return an optional
IPCCommandResult rather than an IPCCommandResult. This removes the need
for a separate boolean that indicates whether the "result" is actually
a reply, and also avoids the need to set dummy result values and ticks.
It also makes it really obvious which commands can result in no reply
being generated.
Finally, this commit renames IPCCommandResult to IPCReply since the
struct is now only used for actual replies. This new name is less
verbose in my opinion.
The diff is quite large since this touches every command handler, but
the only functional change is that I fixed EnqueueIPCReply to
take a s64 for cycles_in_future to match IPCReply.
Some of the device names can be ambiguous and require fully or partly
qualifying the name (e.g. IOS::HLE::FS::) in a somewhat verbose way.
Additionally, insufficiently qualified names are prone to breaking.
Consider the example of IOS::HLE::FS:: (namespace) and
IOS::HLE::Device::FS (class). If we use FS::Foo in a file that doesn't
know about the class, everything will work fine. However, as soon as
Device::FS is declared via a header include or even just forward
declared, that code will cease to compile because FS:: now resolves
to Device::FS if FS::Foo was used in the Device namespace.
It also leads to having to write IOS::ES:: to access ES types and
utilities even for code that is already under the IOS namespace.
The fix for this is simple: rename the device classes and give them
a "device" suffix in their names if the existing ones may be ambiguous.
This makes it clear whether we're referring to the device class or to
something else.
This is not any longer to type, considering it lets us get rid of the
Device namespace, which is now wholly unnecessary.
There are no functional changes in this commit.
A future commit will fix unnecessarily qualified names.
Previously the logging was a in a little bit of a disarray. Some things
were in namespaces, and other things were not.
Given this code will feature a bit of restructuring during the
transition over to fmt, this is a good time to unify it under a single
namespace and also remove functions and types from the global namespace.
Now, all functions and types are under the Common::Log namespace. The
only outliers being, of course, the preprocessor macros.
Pretty much all of the source files contain the following:
namespace IOS
{
namespace HLE
{
namespace <name>
{
// actual code here
} // namespace <name>
} // namespace HLE
} // namespace IOS
which is really verbose boilerplate, because most of the files inside
of Core/IOS are for IOS HLE.
This commit replaces that with a more concise `namespace IOS::HLE`
or `namespace IOS::HLE::(name)`.
This adjusts IOS IPC timing to be closer to actual hardware:
* Emulate the IPC interrupt delay. On a real Wii, from the point of
view of the PPC, the IPC interrupt appears to fire about 100 TB ticks
after Y1/Y2 is seen.
* Fix the IPC acknowledgement delay. Dolphin was much, much too fast.
* Fix Device::GetDefaultReply to return more reasonable delays. Again,
Dolphin was way too fast. We now use a more realistic, average reply
time for most requests.
Note: the previous result from https://dolp.in/pr6374 is flawed.
GetTicketViews definitely takes more than 25µs to reply.
The reason the reply delay was so low is because an invalid
parameter was passed to the libogc wrapper, which causes it to
immediately return an error code (-4100).
* Fix the response delay for various replies that come from the kernel:
fd table full, unknown resource manager / device, invalid fd,
unknown IPC command.
Source: https://github.com/leoetlino/hwtests/blob/af320e4/iostest/ipc_timing.cpp
This commit changes devices to always return IPCCommandResult rather
than just a return code for Open() and Close() in order to be able
to better emulate reply timing.
In hindsight, I should have considered we would want to emulate
timing when I cleaned up the device interface, but alas.
This rectifies that mistake.
This changes the main IOS code (roughly the equivalent of the kernel)
to a class instead of being a set of free functions + tons of static
variables.
The reason for this change is that keeping tons of static variables
like that prevents us from making an IOS instance and reusing IOS
code easily.
Converting the IOS code to a class also allows us to mostly decouple
IOS from the PPC emulation.
The more interesting changes are in Core/IOS/IOS. Everything else is
mostly just boring stuff required by this change...
* Because the devices themselves call back to the main IOS code
for various things (getting the current version, replying to a
request, and other syscall-like functions), just like processes in
IOS call kernel syscalls, we have to pass a reference to the kernel
to anything that uses IOS syscalls.
* Change DoState to save device names instead of device IDs to simplify
AddDevice() and get rid of an ugly static count.
* Change ES_Launch's ack to be sent at IOS boot, now that we can do
this properly.
This changes the IOS code to handle ES contexts inside of ES, instead
of leaking out implementation details into the IPC request dispatcher.
The intent is to clarify what's shared between every single ES context,
and what is specific to an ES context. (Not much.) This should reduce
the number of static members in the ES class.
The other changes are there just because we now keep track of the
IPC FD inside of ES.
Future plans:
* After the WAD direct launch hack is dropped, the title context
will be made a class member.
* Have proper function prototypes, instead of having every single one
of them take ioctlv requests. This will allow reusing IOS code in
other parts of the Dolphin codebase without having to construct
ioctlv requests.
IPC_HLE is actually IOS HLE. The actual IPC emulation is not in
IPC_HLE, but in HW/WII_IPC.cpp. So calling IPC_HLE IOS is more
accurate. (If IOS LLE gets ever implemented, it'll likely be at
a lower level -- Starlet LLE.)
This also totally gets rid of the IPC_HLE prefix in file names, and
moves some source files to their own subdirectories to make the file
hierarchy cleaner.
We're going to get ~14 additional source files with the USB PR,
and this is really needed to keep things from becoming a total pain.
