Move creating gpu blobs to m1n1.

Instead of doing gpu initialization partially in m1n1 and partially in
kernel, build all the blobs in m1n1 and put them in the device tree to be
picked up by the kernel. Most of the code here is copied and pasted kernel
code, with some fixups

Signed-off-by: Asahi Lina <[email protected]>
Co-authored-by: Sasha Finkelstein <[email protected]>
Signed-off-by: Sasha Finkelstein <[email protected]>

Author: hoshinolina

.gitignore

@@ -12,3 +12,5 @@ __pycache__
 /m1n1-*\.src\.rpm
 /m1n1-*\.tar\.gz
 /rust-fatfs-*\.tar\.gz
+target
+.idea

Makefile

@@ -171,7 +171,7 @@ FP_OBJECTS := \
 
 BUILD_OBJS := $(patsubst %,build/%,$(OBJECTS))
 BUILD_FP_OBJS := $(patsubst %,build/%,$(FP_OBJECTS))
-BUILD_ALL_OBJS := $(BUILD_OBJS) $(BUILD_FP_OBJS)
+BUILD_ALL_OBJS := $(BUILD_FP_OBJS) $(BUILD_OBJS)
 NAME := m1n1
 TARGET := m1n1.macho
 TARGET_RAW := m1n1.bin
@@ -191,7 +191,7 @@ rustfmt:
 rustfmt-check:
 	cd rust && cargo fmt --check
 
-build/$(RUST_LIB): rust/src/* rust/*
+build/$(RUST_LIB): rust/src/* rust/* rust/src/gpu/* rust/src/gpu/hw/*
 	$(QUIET)echo "  RS    $@"
 	$(QUIET)mkdir -p $(DEPDIR)
 	$(QUIET)mkdir -p "$(dir $@)"

rust/Cargo.lock

@@ -13,6 +13,7 @@ crate-type = [ "staticlib" ]
 [dependencies]
 fatfs = { path = "vendor/rust-fatfs", default-features = false, features = ["lfn", "alloc"] }
 uuid = { version = "1.7.0", default-features = false }
+versions = { path = "./versions" }
 
 [patch.crates-io]
 uuid = { path = "vendor/uuid" }

rust/Cargo.toml

@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+
+//! Basic soft floating-point support
+//!
+//! The GPU firmware requires a large number of power-related configuration values, many of which
+//! are IEEE 754 32-bit floating point values. These values change not only between GPU/SoC
+//! variants, but also between specific hardware platforms using these SoCs, so they must be
+//! derived from device tree properties. There are many redundant values computed from the same
+//! inputs with simple add/sub/mul/div calculations, plus a few values that are actually specific
+//! to each individual device depending on its binning and fused voltage configuration, so it
+//! doesn't make sense to store the final values to be passed to the firmware in the device tree.
+//!
+//! Therefore, we need a way to perform floating-point calculations in the kernel.
+//!
+//! Using the actual FPU from kernel mode is asking for trouble, since there is no way to bound
+//! the execution of FPU instructions to a controlled section of code without outright putting it
+//! in its own compilation unit, which is quite painful for Rust. Since these calculations only
+//! have to happen at initialization time and there is no need for performance, let's use a simple
+//! software float implementation instead.
+//!
+//! This implementation makes no attempt to be fully IEEE754 compliant, but it's good enough and
+//! gives bit-identical results to macOS in the vast majority of cases, with one or two exceptions
+//! related to slightly non-compliant rounding.
+
+use core::ops;
+
+/// An IEEE754-compatible floating point number implemented in software.
+#[derive(Default, Debug, Copy, Clone)]
+#[repr(transparent)]
+pub struct F32(u32);
+
+#[derive(Default, Debug, Copy, Clone)]
+struct F32U {
+    sign: bool,
+    exp: i32,
+    frac: i64,
+}
+
+impl F32 {
+    #[allow(dead_code)]
+    /// Convert a raw 32-bit representation into an F32
+    pub(crate) const fn from_bits(u: u32) -> F32 {
+        F32(u)
+    }
+
+    // Convert a `f32` value into an F32
+    //
+    // This must ONLY be used in const context. Use the `f32!{}` macro to do it safely.
+    #[doc(hidden)]
+    pub(crate) const fn from_f32(v: f32) -> F32 {
+        // Replace with to_bits() after kernel Rust minreq is >= 1.83.0
+        #[allow(clippy::transmute_float_to_int)]
+        // SAFETY: Transmuting f32 to u32 is always safe
+        F32(unsafe { core::mem::transmute::<f32, u32>(v) })
+    }
+
+    // Convert an F32 into a `f32` value
+    //
+    // For testing only.
+    #[doc(hidden)]
+    #[cfg(test)]
+    pub(crate) fn to_f32(self) -> f32 {
+        f32::from_bits(self.0)
+    }
+
+    const fn unpack(&self) -> F32U {
+        F32U {
+            sign: self.0 & (1 << 31) != 0,
+            exp: ((self.0 >> 23) & 0xff) as i32 - 127,
+            frac: (((self.0 & 0x7fffff) | 0x800000) as i64) << 9,
+        }
+        .norm()
+    }
+}
+
+/// Safely construct an `F32` out of a constant floating-point value.
+///
+/// This ensures that the conversion happens in const context, so no floating point operations are
+/// emitted.
+#[macro_export]
+macro_rules! f32 {
+    ([$($val:expr),*]) => {{
+        [$(f32!($val)),*]
+    }};
+    ($val:expr) => {{
+        const _K: $crate::float::F32 = $crate::float::F32::from_f32($val);
+        _K
+    }};
+}
+
+impl ops::Neg for F32 {
+    type Output = F32;
+
+    fn neg(self) -> F32 {
+        F32(self.0 ^ (1 << 31))
+    }
+}
+
+impl ops::Add<F32> for F32 {
+    type Output = F32;
+
+    fn add(self, rhs: F32) -> F32 {
+        self.unpack().add(rhs.unpack()).pack()
+    }
+}
+
+impl ops::Sub<F32> for F32 {
+    type Output = F32;
+
+    fn sub(self, rhs: F32) -> F32 {
+        self.unpack().add((-rhs).unpack()).pack()
+    }
+}
+
+impl ops::Mul<F32> for F32 {
+    type Output = F32;
+
+    fn mul(self, rhs: F32) -> F32 {
+        self.unpack().mul(rhs.unpack()).pack()
+    }
+}
+
+impl ops::Div<F32> for F32 {
+    type Output = F32;
+
+    fn div(self, rhs: F32) -> F32 {
+        self.unpack().div(rhs.unpack()).pack()
+    }
+}
+
+macro_rules! from_ints {
+    ($u:ty, $i:ty) => {
+        impl From<$i> for F32 {
+            fn from(v: $i) -> F32 {
+                F32U::from_i64(v as i64).pack()
+            }
+        }
+        impl From<$u> for F32 {
+            fn from(v: $u) -> F32 {
+                F32U::from_u64(v as u64).pack()
+            }
+        }
+    };
+}
+
+from_ints!(u8, i8);
+from_ints!(u16, i16);
+from_ints!(u32, i32);
+from_ints!(u64, i64);
+
+impl F32U {
+    const INFINITY: F32U = f32!(f32::INFINITY).unpack();
+    const NEG_INFINITY: F32U = f32!(f32::NEG_INFINITY).unpack();
+
+    fn from_i64(v: i64) -> F32U {
+        F32U {
+            sign: v < 0,
+            exp: 32,
+            frac: v.abs(),
+        }
+        .norm()
+    }
+
+    fn from_u64(mut v: u64) -> F32U {
+        let mut exp = 32;
+        if v >= (1 << 63) {
+            exp = 31;
+            v >>= 1;
+        }
+        F32U {
+            sign: false,
+            exp,
+            frac: v as i64,
+        }
+        .norm()
+    }
+
+    fn shr(&mut self, shift: i32) {
+        if shift > 63 {
+            self.exp = 0;
+            self.frac = 0;
+        } else {
+            self.frac >>= shift;
+        }
+    }
+
+    fn align(a: &mut F32U, b: &mut F32U) {
+        if a.exp > b.exp {
+            b.shr(a.exp - b.exp);
+            b.exp = a.exp;
+        } else {
+            a.shr(b.exp - a.exp);
+            a.exp = b.exp;
+        }
+    }
+
+    fn mul(self, other: F32U) -> F32U {
+        F32U {
+            sign: self.sign != other.sign,
+            exp: self.exp + other.exp,
+            frac: ((self.frac >> 8) * (other.frac >> 8)) >> 16,
+        }
+    }
+
+    fn div(self, other: F32U) -> F32U {
+        if other.frac == 0 || self.is_inf() {
+            if self.sign {
+                F32U::NEG_INFINITY
+            } else {
+                F32U::INFINITY
+            }
+        } else {
+            F32U {
+                sign: self.sign != other.sign,
+                exp: self.exp - other.exp,
+                frac: ((self.frac << 24) / (other.frac >> 8)),
+            }
+        }
+    }
+
+    fn add(mut self, mut other: F32U) -> F32U {
+        F32U::align(&mut self, &mut other);
+        if self.sign == other.sign {
+            self.frac += other.frac;
+        } else {
+            self.frac -= other.frac;
+        }
+        if self.frac < 0 {
+            self.sign = !self.sign;
+            self.frac = -self.frac;
+        }
+        self
+    }
+
+    const fn norm(mut self) -> F32U {
+        let lz = self.frac.leading_zeros() as i32;
+        if lz > 31 {
+            self.frac <<= lz - 31;
+            self.exp -= lz - 31;
+        } else if lz < 31 {
+            self.frac >>= 31 - lz;
+            self.exp += 31 - lz;
+        }
+
+        if self.is_zero() {
+            return F32U {
+                sign: self.sign,
+                frac: 0,
+                exp: 0,
+            };
+        }
+        self
+    }
+
+    const fn is_zero(&self) -> bool {
+        self.frac == 0 || self.exp < -126
+    }
+
+    const fn is_inf(&self) -> bool {
+        self.exp > 127
+    }
+
+    const fn pack(mut self) -> F32 {
+        self = self.norm();
+        if !self.is_zero() {
+            self.frac += 0x100;
+            self = self.norm();
+        }
+
+        if self.is_inf() {
+            if self.sign {
+                return f32!(f32::NEG_INFINITY);
+            } else {
+                return f32!(f32::INFINITY);
+            }
+        } else if self.is_zero() {
+            if self.sign {
+                return f32!(-0.0);
+            } else {
+                return f32!(0.0);
+            }
+        }
+
+        F32(if self.sign { 1u32 << 31 } else { 0u32 }
+            | ((self.exp + 127) as u32) << 23
+            | ((self.frac >> 9) & 0x7fffff) as u32)
+    }
+}
+
+// TODO: Fix failing cases
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_all() {
+        fn add(a: f32, b: f32) {
+            assert_eq!((F32::from_f32(a) + F32::from_f32(b)).to_f32(), a + b);
+        }
+        fn sub(a: f32, b: f32) {
+            assert_eq!((F32::from_f32(a) - F32::from_f32(b)).to_f32(), a - b);
+        }
+        fn mul(a: f32, b: f32) {
+            assert_eq!((F32::from_f32(a) * F32::from_f32(b)).to_f32(), a * b);
+        }
+        fn div(a: f32, b: f32) {
+            assert_eq!((F32::from_f32(a) / F32::from_f32(b)).to_f32(), a / b);
+        }
+
+        fn test(a: f32, b: f32) {
+            add(a, b);
+            sub(a, b);
+            mul(a, b);
+            div(a, b);
+        }
+
+        test(1.123, 7.567);
+        test(1.123, 1.456);
+        test(7.567, 1.123);
+        test(1.123, -7.567);
+        test(1.123, -1.456);
+        test(7.567, -1.123);
+        test(-1.123, -7.567);
+        test(-1.123, -1.456);
+        test(-7.567, -1.123);
+        test(1000.123, 0.001);
+        test(1000.123, 0.0000001);
+        test(0.0012, 1000.123);
+        test(0.0000001, 1000.123);
+        //test(0., 0.);
+        test(0., 1.);
+        test(1., 0.);
+        test(1., 1.);
+        test(2., f32::INFINITY);
+        test(2., f32::NEG_INFINITY);
+        test(f32::INFINITY, 2.);
+        test(f32::NEG_INFINITY, 2.);
+        test(f32::NEG_INFINITY, 2.);
+        test(f32::MAX, 2.);
+        test(f32::MIN, 2.);
+        //test(f32::MIN_POSITIVE, 2.);
+        //test(2., f32::MAX);
+        //test(2., f32::MIN);
+        test(2., f32::MIN_POSITIVE);
+    }
+}