asset, kernel, toolchain: initial picolibc support

DragonMinded · Nov 29, 2024 · a166170 · a166170
1 parent ccfa43b
commit a166170
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Showing 7 changed files with 168 additions and 40 deletions.
diff --git a/src/asset.c b/src/asset.c
@@ -275,7 +275,13 @@ static fpos_t seekfn_none(void *c, fpos_t pos, int whence)
     return -1;
 }
 
+#if defined(__PICOLIBC__) && defined(TINY_STDIO)
+static int readfn_none(void *c, void *buf, size_t sz)
+#elif defined(__PICOLIBC__)
+static int readfn_none(void *c, char *buf, size_t sz)
+#else
 static int readfn_none(void *c, char *buf, int sz)
+#endif
 {
     cookie_none_t *cookie = c;
     assertf(!cookie->seeked, "Cannot seek in file opened via asset_fopen (it might be compressed)");
@@ -299,7 +305,13 @@ typedef struct  {
     uint8_t alignas(8) state[];
 } cookie_cmp_t;
 
+#if defined(__PICOLIBC__) && defined(TINY_STDIO)
+static int readfn_cmp(void *c, void *buf, size_t sz)
+#elif defined(__PICOLIBC__)
+static int readfn_cmp(void *c, char *buf, size_t sz)
+#else
 static int readfn_cmp(void *c, char *buf, int sz)
+#endif
 {
     cookie_cmp_t *cookie = (cookie_cmp_t*)c;
     assertf(!cookie->seeked, "Cannot seek in file opened via asset_fopen (it might be compressed)");

diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
@@ -326,7 +326,7 @@ reg_block_t* __kthread_syscall_schedule(reg_block_t *stack_state)
 
 	th_cur_tp = th_cur->tp_value;
 
-	#ifdef __NEWLIB__
+	#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 	_REENT = th_cur->tls.reent_ptr;
 	#endif
 
@@ -356,7 +356,7 @@ kthread_t* kernel_init(void)
 {
 	assertf(__tdata_align <= 8, "Unsupported TLS alignment of %d (Maximum 8)", __tdata_align);
 	assert(!__kernel);
-	#ifdef __NEWLIB__
+	#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 	// Check if __malloc_lock is a nop. This happens with old toolchains where
 	// newlib was compiled with --disable-threads.
 	extern void __malloc_lock(void);
@@ -383,7 +383,7 @@ kthread_t* kernel_init(void)
 	th_main.flags = TH_FLAG_DETACHED; // main thread cannot be joined
 	th_main.tp_value = __tls_base+TP_OFFSET;
 
-	#ifdef __NEWLIB__
+	#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 	th_main.tls.reent_ptr = _REENT;
 	#endif
 
@@ -450,7 +450,7 @@ kthread_t* __kthread_new_internal(const char *name, int stack_size, int8_t pri,
 	// make debugging more difficult and might even cause the kernel to crash.
 
 	int extra_size = TLS_SIZE;
-	#ifdef __NEWLIB__
+	#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 	extra_size += sizeof(struct _reent);
 	#endif
 	void *thmem = malloc(STACK_GUARD + stack_size + sizeof(kthread_t) + extra_size);
@@ -516,7 +516,7 @@ kthread_t* __kthread_new_internal(const char *name, int stack_size, int8_t pri,
 	th->tp_value = extra+TP_OFFSET;
 	extra += TLS_SIZE;
 	// TLS initial configuration
-	#ifdef __NEWLIB__
+	#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 	th->tls.reent_ptr = extra;
 	_REENT_INIT_PTR(th->tls.reent_ptr);
 	#endif

diff --git a/src/kernel/kernel_internal.h b/src/kernel/kernel_internal.h
@@ -7,7 +7,7 @@
 #define __LIBDRAGON_KERNEL_INTERNAL_H
 
 #include "kernel.h"
-#ifdef __NEWLIB__
+#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 #include <sys/reent.h>
 #endif
 
@@ -57,7 +57,7 @@ typedef struct __attribute__((aligned (8))) kthread_s
 		int interrupt_depth;
 		/** Mirror of __interrupt_sr  */
 		int interrupt_sr;
-		#ifdef __NEWLIB__
+		#if defined(__NEWLIB__) && !defined(__PICOLIBC__)
 		/** Newlib reentrancy */
 		struct _reent *reent_ptr;
 		#endif

diff --git a/src/system.c b/src/system.c
@@ -10,6 +10,7 @@
 #include <fcntl.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/time.h>
 #include <sys/times.h>
 #include <stdarg.h>
 #include <stdint.h>
@@ -35,6 +36,13 @@
 #define STDERR_FILENO   2
 /** @} */
 
+#if defined(__PICOLIBC__) && defined(TINY_STDIO)
+/* Force weakly referenced default stdin/stdout/stderr implementations to be linked. */
+__asm__(".equ stdin_reference, stdin");
+__asm__(".equ stdout_reference, stdout");
+__asm__(".equ stderr_reference, stderr");
+#endif
+
 /**
  * @brief Stack size
  *

diff --git a/src/system_newlib_locks.c b/src/system_newlib_locks.c
@@ -12,6 +12,7 @@
  */
 #include "kernel.h"
 #include <stdio.h>
+#include <sys/lock.h>
 
 // Toolchains since Sept 2024 build with threads and retargetable locks enabled,
 // both of which are required for libc to be thread safe and thus the kernel
@@ -118,4 +119,4 @@ void __retarget_lock_release_recursive (_LOCK_T lock) {
 
 ///@endcond
 
-#endif
+#endif
diff --git a/tools/build-toolchain.sh b/tools/build-toolchain.sh
@@ -22,6 +22,14 @@ N64_BUILD=${N64_BUILD:-""}
 N64_HOST=${N64_HOST:-""}
 N64_TARGET=${N64_TARGET:-mips64-elf}
 
+# Toolchain configuration options.
+N64_USE_PICOLIBC=${N64_USE_PICOLIBC:-"false"}
+N64_USE_PICOLIBC_TINYSTDIO=${N64_USE_PICOLIBC_TINYSTDIO:-"false"}
+N64_USE_PICOLIBC_LEGACY_STDIO=true
+if [ "$N64_USE_PICOLIBC_TINYSTDIO" == "true" ]; then
+    N64_USE_PICOLIBC_LEGACY_STDIO=false
+fi
+
 # Set N64_INST before calling the script to change the default installation directory path
 INSTALL_PATH="${N64_INST}"
 # Set PATH for newlib to compile using GCC for MIPS N64 (pass 1)
@@ -38,8 +46,9 @@ GCC_CONFIGURE_ARGS=()
 BINUTILS_V=2.43.1
 GCC_V=14.2.0
 NEWLIB_V=4.4.0.20231231
-GMP_V=6.3.0 
-MPC_V=1.3.1 
+PICOLIBC_V=e0a04fec075f5cb1ddb80ea8c359748ef72b9122
+GMP_V=6.3.0
+MPC_V=1.3.1
 MPFR_V=4.2.1
 MAKE_V=${MAKE_V:-""}
 
@@ -104,8 +113,13 @@ test -d "binutils-$BINUTILS_V"        || tar -xzf "binutils-$BINUTILS_V.tar.gz"
 test -f "gcc-$GCC_V.tar.gz"           || download "https://ftp.gnu.org/gnu/gcc/gcc-$GCC_V/gcc-$GCC_V.tar.gz"
 test -d "gcc-$GCC_V"                  || tar -xzf "gcc-$GCC_V.tar.gz"
 
-test -f "newlib-$NEWLIB_V.tar.gz"     || download "https://sourceware.org/pub/newlib/newlib-$NEWLIB_V.tar.gz"
-test -d "newlib-$NEWLIB_V"            || tar -xzf "newlib-$NEWLIB_V.tar.gz"
+if [ "$N64_USE_PICOLIBC" == "true" ]; then
+    test -f "picolibc-$PICOLIBC_V.zip"    || ( download "https://github.com/picolibc/picolibc/archive/$PICOLIBC_V.zip" && mv "$PICOLIBC_V.zip" "picolibc-$PICOLIBC_V.zip" )
+    test -d "picolibc-$PICOLIBC_V"        || unzip "picolibc-$PICOLIBC_V.zip"
+else
+    test -f "newlib-$NEWLIB_V.tar.gz"     || download "https://sourceware.org/pub/newlib/newlib-$NEWLIB_V.tar.gz"
+    test -d "newlib-$NEWLIB_V"            || tar -xzf "newlib-$NEWLIB_V.tar.gz"
+fi
 
 if [ "$GMP_V" != "" ]; then
     test -f "gmp-$GMP_V.tar.bz2"           || download "https://ftp.gnu.org/gnu/gmp/gmp-$GMP_V.tar.bz2"
@@ -220,20 +234,57 @@ make all-target-libgcc -j "$JOBS"
 make install-target-libgcc || sudo make install-target-libgcc || su -c "make install-target-libgcc"
 popd
 
-# Compile newlib for target.
-mkdir -p newlib_compile_target
-pushd newlib_compile_target
-CFLAGS_FOR_TARGET="-DHAVE_ASSERT_FUNC -O2 -fpermissive" ../"newlib-$NEWLIB_V"/configure \
-    --prefix="$CROSS_PREFIX" \
-    --target="$N64_TARGET" \
-    --with-cpu=mips64vr4300 \
-    --disable-libssp \
-    --disable-werror \
-    --enable-newlib-multithread \
-    --enable-newlib-retargetable-locking
-make -j "$JOBS"
-make install || sudo env PATH="$PATH" make install || su -c "env PATH=\"$PATH\" make install"
-popd
+if [ "$N64_USE_PICOLIBC" == "true" ]; then
+    # Compile picolibc for target.
+    mkdir -p picolibc_compile_target
+    pushd picolibc_compile_target
+    meson setup \
+        --cross-file=../../meson-cross.txt \
+        -Dmultilib=false \
+        -Dpicocrt=false \
+        -Dpicolib=false \
+        -Dsemihost=false \
+        -Dspecsdir=none \
+        -Dtests=false \
+        -Dtinystdio="$N64_USE_PICOLIBC_TINYSTDIO" \
+        -Dfast-bufio=true \
+        -Dio-long-long=true \
+        -Dio-pos-args="$N64_USE_PICOLIBC_TINYSTDIO" \
+        -Dio-percent-b=true \
+        -Dposix-console=true \
+        -Dformat-default=double \
+        -Dnewlib-fseek-optimization="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+        -Dnewlib-fvwrite-in-streamio="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+        -Dnewlib-io-float="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+        -Dnewlib-stdio64=false \
+        -Dnewlib-unbuf-stream-opt="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+        -Dnewlib-nano-malloc=false \
+        -Dnewlib-multithread=true \
+        -Dnewlib-retargetable-locking=true \
+        -Dthread-local-storage=true \
+        -Dprefix="$CROSS_PREFIX" \
+        -Dlibdir=mips64-elf/lib \
+        -Dincludedir=mips64-elf/include \
+        ../"picolibc-$PICOLIBC_V"
+    ninja -j "$JOBS"
+    ninja install || sudo env PATH="$PATH" ninja install || su -c "env PATH=\"$PATH\" ninja install"
+    popd
+else
+    # Compile newlib for target.
+    mkdir -p newlib_compile_target
+    pushd newlib_compile_target
+    CFLAGS_FOR_TARGET="-DHAVE_ASSERT_FUNC -O2 -fpermissive" ../"newlib-$NEWLIB_V"/configure \
+        --prefix="$CROSS_PREFIX" \
+        --target="$N64_TARGET" \
+        --with-cpu=mips64vr4300 \
+        --disable-libssp \
+        --disable-werror \
+        --enable-newlib-multithread \
+        --enable-newlib-retargetable-locking
+    make -j "$JOBS"
+    make install || sudo env PATH="$PATH" make install || su -c "env PATH=\"$PATH\" make install"
+    popd
+fi
 
 # For a standard cross-compiler, the only thing left is to finish compiling the target libraries
 # like libstd++. We can continue on the previous GCC build target.
@@ -286,20 +337,57 @@ else
     make install-target-libgcc || sudo make install-target-libgcc || su -c "make install-target-libgcc"
     popd
 
-    # Compile newlib for target.
-    mkdir -p newlib_compile
-    pushd newlib_compile
-    CFLAGS_FOR_TARGET="-DHAVE_ASSERT_FUNC -O2 -fpermissive" ../"newlib-$NEWLIB_V"/configure \
-        --prefix="$INSTALL_PATH" \
-        --target="$N64_TARGET" \
-        --with-cpu=mips64vr4300 \
-        --disable-libssp \
-        --disable-werror \
-        --enable-newlib-multithread \
-        --enable-newlib-retargetable-locking
-    make -j "$JOBS"
-    make install || sudo env PATH="$PATH" make install || su -c "env PATH=\"$PATH\" make install"
-    popd
+    if [ "$N64_USE_PICOLIBC" == "true" ]; then
+        # Compile picolibc for target.
+        mkdir -p picolibc_compile_target
+        pushd picolibc_compile_target
+        meson setup \
+            --cross-file=../../meson-cross.txt \
+            -Dmultilib=false \
+            -Dpicocrt=false \
+            -Dpicolib=false \
+            -Dsemihost=false \
+            -Dspecsdir=none \
+            -Dtests=false \
+            -Dtinystdio="$N64_USE_PICOLIBC_TINYSTDIO" \
+            -Dfast-bufio=true \
+            -Dio-long-long=true \
+            -Dio-pos-args="$N64_USE_PICOLIBC_TINYSTDIO" \
+            -Dio-percent-b=true \
+            -Dposix-console=true \
+            -Dformat-default=double \
+            -Dnewlib-fseek-optimization="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+            -Dnewlib-fvwrite-in-streamio="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+            -Dnewlib-io-float="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+            -Dnewlib-stdio64=false \
+            -Dnewlib-unbuf-stream-opt="$N64_USE_PICOLIBC_LEGACY_STDIO" \
+            -Dnewlib-nano-malloc=false \
+            -Dnewlib-multithread=true \
+            -Dnewlib-retargetable-locking=true \
+            -Dthread-local-storage=false \
+            -Dprefix="$INSTALL_PATH" \
+            -Dlibdir=mips64-elf/lib \
+            -Dincludedir=mips64-elf/include \
+            ../"picolibc-$PICOLIBC_V"
+        ninja -j "$JOBS"
+        ninja install || sudo env PATH="$PATH" ninja install || su -c "env PATH=\"$PATH\" ninja install"
+        popd
+    else
+        # Compile newlib for target.
+        mkdir -p newlib_compile_target
+        pushd newlib_compile_target
+        CFLAGS_FOR_TARGET="-DHAVE_ASSERT_FUNC -O2 -fpermissive" ../"newlib-$NEWLIB_V"/configure \
+            --prefix="$INSTALL_PATH" \
+            --target="$N64_TARGET" \
+            --with-cpu=mips64vr4300 \
+            --disable-libssp \
+            --disable-werror \
+            --enable-newlib-multithread \
+            --enable-newlib-retargetable-locking
+        make -j "$JOBS"
+        make install || sudo env PATH="$PATH" make install || su -c "env PATH=\"$PATH\" make install"
+        popd
+    fi
 
     # Finish compiling GCC
     mkdir -p gcc_compile

diff --git a/tools/meson-cross.txt b/tools/meson-cross.txt
@@ -0,0 +1,19 @@
+[binaries]
+# Meson 0.53.2 doesn't use any cflags when doing basic compiler tests,
+# so we have to add -nostdlib to the compiler configuration itself or
+# early compiler tests will fail. This can be removed when picolibc
+# requires at least version 0.54.2 of meson.
+c = ['mips64-elf-gcc', '-nostdlib']
+ar = 'mips64-elf-ar'
+as = 'mips64-elf-as'
+nm = 'mips64-elf-nm'
+strip = 'mips64-elf-strip'
+
+[host_machine]
+system = 'none'
+cpu_family = 'mips64'
+cpu = 'mips64vr4300'
+endian = 'big'
+
+[properties]
+skip_sanity_check = true