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psx/hw/cop: Support cfc2 and ctc2 op codes to access GTE Control Registers #49

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psx/hw/cop: Support cfc2 and ctc2 op codes to access GTE Control Registers #49

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7199300
psx/hw/cop: Use .long to form unsupported cop2 opcodes
hornc Nov 18, 2025
84fa88e
Use $at to hold the value from asm! macro reg
hornc Nov 19, 2025
1ab40ed
psx/hw/gte: Add two more cop2 registers, nop delay for read from cop
hornc Nov 19, 2025
1c0507e
psx/hw/gte: Define intermediate GTE registers
hornc Nov 19, 2025
a0d06c2
psx/hw/cop: add cop_move! asm generating macro
hornc Nov 20, 2025
ff2d012
psx/hw/gte: Define remaining GTE registers
hornc Nov 21, 2025
eb3d107
Fix typo in register name
hornc Nov 21, 2025
df4c708
psx/hw/cop: 2 delay slots for GTE load and store
hornc Nov 25, 2025
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44 changes: 40 additions & 4 deletions psx/src/hw/cop.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -19,11 +19,47 @@ impl<T: Primitive, const COP: u32, const REG: u32> AsMut<T> for CopRegister<T, C
}
}

macro_rules! cop_move {
("m", from, $cop:expr, $reg:expr) => {
concat!(
"mfc", $cop, " {}, $", $reg, "\n",
"nop\n",
"nop", // 2 delay slots required to ensure value is in out(reg)
)
};
("m", to, $cop:expr, $reg:expr) => {
concat!("mtc", $cop, " {}, $", $reg, "\n",
"nop\n",
"nop"
)
};
("c", from, $cop:expr, $reg:expr) => {
//concat!("cfc", $cop, " {}, $", $reg) # Not currently supported by LLVM
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@ayrtonm ayrtonm Nov 30, 2025

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It's just cfc2/ctc2 instructions that aren't supported by LLVM right? I think this comment would be clearer if it just said that instead of having the commented out concat!....

concat!(
// cop n CF rt=$at rd=$reg - 32
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@ayrtonm ayrtonm Nov 30, 2025

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Can you expand on this comment? I understand what the .long directive is doing, but it'd be nice to have it spelled out like in the rust psp crate for the next person that stumbles on this code.

".long 1<<30 | ", $cop, "<<26 | 2<<21 | 1<<16 | (", $reg, "-32)<<11 # cfc", $cop, "\n",
"nop\n",
"nop\n",
"addiu {}, $at, 0"
)
};
("c", to, $cop:expr, $reg:expr) => {
//concat!("ctc", $cop, " {}, $", $reg) # Not currently supported by LLVM
concat!(
"addiu $at, {}, 0\n",
// cop n CT rt=$at rd=$reg - 32
".long 1<<30 | ", $cop, "<<26 | 6<<21 | 1<<16 | (", $reg, "-32)<<11 # ctc", $cop, "\n",
"nop\n",
"nop",
)
};
}

macro_rules! define_cop {
($(#[$($meta:meta)*])* $name:ident <$ty:ty>; COP: $cop:expr; R: $reg:expr $(,)?) => {
define_cop!($(#[$($meta)*])* $name<$ty>; COP: $cop; R: $reg; "m");
};
($(#[$($meta:meta)*])* $name:ident <$ty:ty>; COP: $cop:expr; R: $reg:expr; $cop_ty:literal $(,)?) => {
($(#[$($meta:meta)*])* $name:ident <$ty:ty>; COP: $cop:expr; R: $reg:expr; $cop_ty:tt $(,)?) => {
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@ayrtonm ayrtonm Nov 30, 2025

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$cop_ty:expr should also work since that's what cop_move! expects right? Might be somewhat clearer to use that instead of $cop_ty:tt.

$(#[$($meta)*])*
pub type $name = crate::hw::cop::CopRegister<$ty, $cop, $reg>;

Expand All @@ -35,7 +71,7 @@ macro_rules! define_cop {
unsafe {
core::arch::asm! {
".set noat",
concat!($cop_ty, "fc", $cop, " {}, $", $reg),
cop_move!($cop_ty, from, $cop, $reg),
".set at",
out(reg) self.value,
options(nomem, nostack)
Expand All @@ -48,7 +84,7 @@ macro_rules! define_cop {
unsafe {
core::arch::asm! {
".set noat",
concat!($cop_ty, "tc", $cop, " {}, $", $reg),
cop_move!($cop_ty, to, $cop, $reg),
".set at",
in(reg) self.value,
options(nomem, nostack)
Expand All @@ -58,7 +94,7 @@ macro_rules! define_cop {
}
}
};
($(#[$($meta:meta)*])* $name:ident <$ty:ty>; COP: $cop:expr; R: $reg:expr $(;$cop_ty:literal)?, $($others:tt)*) => {
($(#[$($meta:meta)*])* $name:ident <$ty:ty>; COP: $cop:expr; R: $reg:expr $(;$cop_ty:tt)?, $($others:tt)*) => {
define_cop!($(#[$($meta)*])* $name<$ty>; COP: $cop; R: $reg $(;$cop_ty)*);
define_cop!($($others)*);
};
Expand Down
118 changes: 100 additions & 18 deletions psx/src/hw/gte.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -17,10 +17,48 @@ define_cop! {
VXY2<u32>; COP: 2; R: 4,
/// The 16-bit VZ2 vector
VZ2<i16>; COP: 2; R: 5,

/// RGB value
RGB<u32>; COP: 2; R: 6,
/// Ordering table average Z value
OTZ<u16>; COP: 2; R: 7,

/// Intermediate value 0
IR0<u32>; COP: 2; R: 8,
/// Intermediate value 1
IR1<u32>; COP: 2; R: 9,
/// Intermediate value 2
IR2<u32>; COP: 2; R: 10,
/// Intermediate value 3
IR3<u32>; COP: 2; R: 11,

/// Screen XY coord FIFO 0
SXY0<u32>; COP: 2; R: 12,
/// Screen XY coord FIFO 1
SXY1<u32>; COP: 2; R: 13,
/// Screen XY coord FIFO 2
SXY2<u32>; COP: 2; R: 14,
/// Screen XY coord FIFO P
SXYP<u32>; COP: 2; R: 15,

/// Screen Z FIFO 0
SZ0<u16>; COP: 2; R: 16,
/// Screen Z FIFO 1
SZ1<u16>; COP: 2; R: 17,
/// Screen Z FIFO 2
SZ2<u16>; COP: 2; R: 18,
/// Screen Z FIFO 3
SZ3<u16>; COP: 2; R: 19,

/// Characteristic color FIFO 0
RGB0<u32>; COP: 2; R: 20,
/// Characteristic color FIFO 1
RGB1<u32>; COP: 2; R: 21,
/// Characteristic color FIFO 2
RGB2<u32>; COP: 2; R: 22,

/// Unused / Prohibited
RES1<u32>; COP: 2; R: 23,

/// Scalar math accumulator
MAC0<i32>; COP: 2; R: 24,

Expand All @@ -31,44 +69,88 @@ define_cop! {
/// The third component of the vector math accumulator
MAC3<i32>; COP: 2; R: 27,

/// IRGB
IRGB<u16>; COP: 2; R: 28,
/// ORGB
ORGB<u16>; COP: 2; R: 29,

/// Leading zeros count source
LZCS<u32>; COP: 2; R: 30,
/// Leading zeros count result
LZCR<u32>; COP: 2; R: 31,

/*
TODO: LLVM doesn't support these coprocessor instructions yet (#7).
/// Rotation matrix entries RT11 and RT12
RT11_12<u32>; COP: 2; R: 32; "c",

/// Rotation matrix entries RT13 and RT21
RT13_21<u32>; COP: 2; R: 33,
RT13_21<u32>; COP: 2; R: 33; "c",
/// Rotation matrix entries RT22 and RT23
RT22_23<u32>; COP: 2; R: 34,
RT22_23<u32>; COP: 2; R: 34; "c",
/// Rotation matrix entries RT31 and RT32
RT31_32<u32>; COP: 2; R: 35,
RT31_32<u32>; COP: 2; R: 35; "c",
/// Rotation matrix entry RT33
RT33<i16>; COP: 2; R: 36,
RT33<i16>; COP: 2; R: 36; "c",

/// Translation vector X
TRX<i32>; COP: 2; R: 37; "c",
/// Translation vector Y
TRY<i32>; COP: 2; R: 38; "c",
/// Translation vector Z
TRZ<i32>; COP: 2; R: 39; "c",

/// Light matrix entries L11 and L12
L11_12<u32>; COP: 2; R: 40,
L11_12<u32>; COP: 2; R: 40; "c",
/// Light matrix entries L13 and L21
L13_21<u32>; COP: 2; R: 41,
L13_21<u32>; COP: 2; R: 41; "c",
/// Light matrix entries L22 and L23
L22_23<u32>; COP: 2; R: 42,
L22_23<u32>; COP: 2; R: 42; "c",
/// Light matrix entries L31 and L32
L31_32<u32>; COP: 2; R: 43,
L31_32<u32>; COP: 2; R: 43; "c",
/// Light matrix entry L33
L33<i16>; COP: 2; R: 44,
L33<i16>; COP: 2; R: 44; "c",

/// Background color red component
RBK<u32>; COP: 2; R: 45; "c",
/// Background color green component
GBK<u32>; COP: 2; R: 46; "c",
/// Background color blue component
BBK<u32>; COP: 2; R: 47; "c",

/// Light color matrix entries LR11 and LR12
LR11_12<u32>; COP: 2; R: 48,
LR11_12<u32>; COP: 2; R: 48; "c",
/// Light color matrix entries LR13 and LR21
LR13_21<u32>; COP: 2; R: 49,
LR13_21<u32>; COP: 2; R: 49; "c",
/// Light color matrix entries LR22 and LR23
LR22_23<u32>; COP: 2; R: 50,
LR22_23<u32>; COP: 2; R: 50; "c",
/// Light color matrix entries LR31 and LR32
LR31_32<u32>; COP: 2; R: 51,
LR31_32<u32>; COP: 2; R: 51; "c",
/// Light color matrix entry LR33
LR33<i16>; COP: 2; R: 52,
*/
LR33<i16>; COP: 2; R: 52; "c",

/// Far color red component
RFC<u32>; COP: 2; R: 53; "c",
/// Far color green component
GFC<u32>; COP: 2; R: 54; "c",
/// Far color blue component
BFC<u32>; COP: 2; R: 55; "c",

/// Screen Offset and Distance X
OFX<u32>; COP: 2; R: 56; "c",
/// Screen Offset and Distance Y
OFY<u32>; COP: 2; R: 57; "c",
/// Projection plane distance
H<i16>; COP: 2; R: 58; "c",

/// Depth queuing parameter A. (coefficient)
DQA<u32>; COP: 2; R: 59; "c",
/// Depth queuing parameter B. (offset)
DQB<u32>; COP: 2; R: 60; "c",

/// Z3 average scale factor (normally 1/3)
ZSF3<u32>; COP: 2; R: 61; "c",
/// Z4 average scale factor (normally 1/4)
ZSF4<u32>; COP: 2; R: 62; "c",

/// Error code status
FLAG<u32>; COP: 2; R: 63; "c",
}