Added basic rust library for testing

.cargo/config.toml

@@ -0,0 +1,5 @@
+[build]
+target = "riscv64gc-unknown-none-elf"
+
+[target.riscv64-unknown-elf]
+linker = "/opt/riscv/bin/riscv64-unknown-elf-gcc"

.rustfmt.toml

@@ -0,0 +1 @@
+hard_tabs = true

Makefile

@@ -1,5 +1,9 @@
 K=kernel
 U=user
+R=rust
+
+RTARGET = riscv64gc-unknown-none-elf
+RENV = debug
 
 OBJS = \
   $K/entry.o \
@@ -30,6 +34,9 @@ OBJS = \
   $K/plic.o \
   $K/virtio_disk.o
 
+RLIBS = \
+	$R/foo/target/$(RTARGET)/$(RENV)/libfoo.rlib
+
 # riscv64-unknown-elf- or riscv64-linux-gnu-
 # perhaps in /opt/riscv/bin
 #TOOLPREFIX = 
@@ -73,8 +80,8 @@ endif
 
 LDFLAGS = -z max-page-size=4096
 
-$K/kernel: $(OBJS) $K/kernel.ld $U/initcode
-	$(LD) $(LDFLAGS) -T $K/kernel.ld -o $K/kernel $(OBJS) 
+$K/kernel: $(OBJS) $K/kernel.ld $U/initcode rustlibs
+	$(LD) $(LDFLAGS) -T $K/kernel.ld -o $K/kernel $(OBJS) $(RLIBS)
 	$(OBJDUMP) -S $K/kernel > $K/kernel.asm
 	$(OBJDUMP) -t $K/kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $K/kernel.sym
 
@@ -138,6 +145,9 @@ fs.img: mkfs/mkfs README $(UPROGS)
 
 -include kernel/*.d user/*.d
 
+rustlibs:
+	cargo build --manifest-path $R/foo/Cargo.toml
+
 clean: 
 	rm -f *.tex *.dvi *.idx *.aux *.log *.ind *.ilg \
 	*/*.o */*.d */*.asm */*.sym \
@@ -145,6 +155,7 @@ clean:
 	mkfs/mkfs .gdbinit \
         $U/usys.S \
 	$(UPROGS)
+	cargo clean --manifest-path $R/foo/Cargo.toml
 
 # try to generate a unique GDB port
 GDBPORT = $(shell expr `id -u` % 5000 + 25000)

rust/foo/.gitignore

@@ -0,0 +1 @@
+/target

rust/foo/Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "foo"
+version = "0.1.0"

rust/foo/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "foo"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

rust/foo/src/lib.rs

@@ -0,0 +1,5 @@
+#![no_std]
+
+pub fn add(left: usize, right: usize) -> usize {
+	left + right + 5
+}