5 files changed, 221 insertions, 0 deletions

diff --git a/meta/recipes-core/picolibc/picolibc-helloworld_git.bb b/meta/recipes-core/picolibc/picolibc-helloworld_git.bb
new file mode 100644
index 0000000000..573a571c24
--- /dev/null
+++ b/meta/recipes-core/picolibc/picolibc-helloworld_git.bb
@@ -0,0 +1,40 @@
+require picolibc.inc
+
+# baremetal-image overrides
+BAREMETAL_BINNAME ?= "hello_picolibc_${MACHINE}"
+IMAGE_LINK_NAME ?= "baremetal-picolibc-image-${MACHINE}"
+IMAGE_NAME_SUFFIX ?= ""
+QB_DEFAULT_KERNEL ?= "${IMAGE_LINK_NAME}.elf"
+
+inherit baremetal-image
+
+COMPATIBLE_MACHINE = "qemuarm|qemuarm64|qemuriscv32|qemuriscv64"
+
+# Use semihosting to test via QEMU
+QB_OPT_APPEND:append = " -semihosting-config enable=on"
+
+# picolibc comes with a set of linker scripts, set the file
+# according to the architecture being built.
+PICOLIBC_LINKERSCRIPT:qemuarm64 = "aarch64.ld"
+PICOLIBC_LINKERSCRIPT:qemuarm = "arm.ld"
+PICOLIBC_LINKERSCRIPT:qemuriscv32 = "riscv.ld"
+PICOLIBC_LINKERSCRIPT:qemuriscv64 = "riscv.ld"
+
+# Simple compile function that manually exemplifies usage; as noted,
+# use a custom linker script, the GCC specs provided by picolibc
+# and semihost to be able to test via QEMU's monitor
+do_compile(){
+    ${CC} ${CFLAGS} ${LDFLAGS} --verbose -T${S}/hello-world/${PICOLIBC_LINKERSCRIPT} -specs=picolibc.specs --oslib=semihost -o ${BAREMETAL_BINNAME}.elf ${S}/hello-world/hello-world.c
+    ${OBJCOPY} -O binary ${BAREMETAL_BINNAME}.elf ${BAREMETAL_BINNAME}.bin
+}
+
+do_install(){
+    install -d ${D}/${base_libdir}/firmware
+    install -m 755 ${B}/${BAREMETAL_BINNAME}.elf ${D}/${base_libdir}/firmware/${BAREMETAL_BINNAME}.elf
+    install -m 755 ${B}/${BAREMETAL_BINNAME}.bin ${D}/${base_libdir}/firmware/${BAREMETAL_BINNAME}.bin
+}
+
+FILES:${PN} += " \
+    ${base_libdir}/firmware/${BAREMETAL_BINNAME}.elf \
+    ${base_libdir}/firmware/${BAREMETAL_BINNAME}.bin \
+"
diff --git a/meta/recipes-core/picolibc/picolibc.inc b/meta/recipes-core/picolibc/picolibc.inc
new file mode 100644
index 0000000000..3b380fe7af
--- /dev/null
+++ b/meta/recipes-core/picolibc/picolibc.inc
@@ -0,0 +1,21 @@
+SUMMARY = "C Libraries for Smaller Embedded Systems"
+HOMEPAGE = "https://keithp.com/picolibc"
+DESCRIPTION = "Picolibc is a set of standard C libraries, both libc and libm, designed for smaller embedded systems with limited ROM and RAM. Picolibc includes code from Newlib and AVR Libc."
+SECTION = "libs"
+
+# Newlib based code but GPL related bits removed, test/printf-tests.c and test/testcases.c
+# are GPLv2 and GeneratePicolibcCrossFile.sh is AGPL3 but not part of the artifacts.
+LICENSE = "BSD-2-Clause & BSD-3-Clause"
+LIC_FILES_CHKSUM = " \
+                file://COPYING.GPL2;md5=59530bdf33659b29e73d4adb9f9f6552 \
+                file://COPYING.NEWLIB;md5=08ae03456feb75b81cfdb359e0f1ef85 \
+                file://COPYING.picolibc;md5=e50fa9458a40929689861ed472d46bc7 \
+                "
+
+BASEVER = "1.8.6"
+PV = "${BASEVER}+git"
+SRC_URI = "git://github.com/picolibc/picolibc.git;protocol=https;branch=main"
+SRCREV="764ef4e401a8f4c6a86ab723533841f072885a5b"
+
+S = "${WORKDIR}/git"
+B = "${WORKDIR}/build"
diff --git a/meta/recipes-core/picolibc/picolibc/avoid_polluting_cross_directories.patch b/meta/recipes-core/picolibc/picolibc/avoid_polluting_cross_directories.patch
new file mode 100644
index 0000000000..da6460c95c
--- /dev/null
+++ b/meta/recipes-core/picolibc/picolibc/avoid_polluting_cross_directories.patch
@@ -0,0 +1,119 @@
+Upstream-Status: Pending
+
+Picolibc uses its own specs file: picolibc.specs to facilitate compilation, this
+needs to be passed down to GCC via the -specs argument.
+
+Using this specs file overrides some of the default options our toolchain was
+built with, in this case, they modify the include_dir and lib_dir paths used for
+compilation, their intention was to add support for -picolibc-prefix and
+-picolibc-buildtype arguments via the C preprocessor.
+
+-isystem %{-picolibc-prefix=*:%*/include/; -picolibc-buildtype=*:/usr/include/%*; :/usr/include} %(picolibc_cpp)
+
+This had the unwanted effect of defaulting to /usr/include for include_dir if
+those arguments are not being passed, this works fine for their flow but for us
+it pollutes the include directories with paths from the host. The same effect is
+applicable for lib_dir and for the c runtime file.
+
+Our toolchain relies on --sysroot to avoid using any paths from the host, here we
+manually add support for a third possible argument: -sysroot , if this is passed
+then the paths used by the compiler will be relative to the path passed by the
+--sysroot= cmdline argument, setting back the behavior that we intended in the
+first place.
+
+
+Signed-off-by: Alejandro Enedino Hernandez Samaniego <alejandro@enedino.org>
+
+Index: git/meson.build
+===================================================================
+--- git.orig/meson.build
++++ git/meson.build
+@@ -622,12 +622,13 @@ else
+ #
+ picolibc_prefix_format = '-picolibc-prefix=*:@0@'
+ picolibc_buildtype_format = '-picolibc-buildtype=*:@0@'
++sysroot_format = '-sysroot=*:@0@'
+ gen_format = '@0@'
+ 
+ #
+ # How to glue the three options together
+ #
+-specs_option_format = '%{@0@; @1@; :@2@}'
++specs_option_format = '%{@0@; @1@; @2@; :@3@}'
+ 
+ #
+ # Build the -isystem value
+@@ -639,10 +640,13 @@ isystem_prefix = picolibc_prefix_format.
+ buildtype_include_dir = specs_prefix_format.format(get_option('includedir') / '%*')
+ isystem_buildtype = picolibc_buildtype_format.format(buildtype_include_dir)
+ 
++sysroot_include_dir = '%*'
++isystem_sysroot = sysroot_format.format(sysroot_include_dir)
++
+ gen_include_dir = specs_prefix_format.format(get_option('includedir'))
+ isystem_gen = gen_format.format(gen_include_dir)
+ 
+-specs_isystem = '-isystem ' + specs_option_format.format(isystem_prefix, isystem_buildtype, isystem_gen)
++specs_isystem = '-isystem ' + specs_option_format.format(isystem_prefix, isystem_buildtype, isystem_sysroot, isystem_gen)
+ 
+ #
+ # Build the non-multilib -L value
+@@ -654,10 +658,13 @@ lib_prefix = picolibc_prefix_format.form
+ buildtype_lib_dir = specs_prefix_format.format(get_option('libdir') / '%*')
+ lib_buildtype = picolibc_buildtype_format.format(buildtype_lib_dir)
+ 
++sysroot_lib_dir = '%*'
++lib_sysroot = sysroot_format.format(sysroot_lib_dir)
++
+ gen_lib_dir = specs_prefix_format.format(get_option('libdir'))
+ lib_gen = gen_format.format(gen_lib_dir)
+ 
+-specs_libpath = '-L' + specs_option_format.format(lib_prefix, lib_buildtype, lib_gen)
++specs_libpath = '-L' + specs_option_format.format(lib_prefix, lib_buildtype, lib_sysroot, lib_gen)
+ 
+ #
+ # Build the non-multilib *startfile options
+@@ -669,6 +676,9 @@ crt0_prefix = picolibc_prefix_format.for
+ buildtype_crt0_path = specs_prefix_format.format(get_option('libdir') / '%*' / crt0_expr)
+ crt0_buildtype = picolibc_buildtype_format.format(buildtype_crt0_path)
+ 
++sysroot_crt0_path = '%*' + '/' + get_option('libdir') + '/' + '%*' + '/' + crt0_expr
++crt0_sysroot = picolibc_buildtype_format.format(sysroot_crt0_path)
++
+ gen_crt0_path = specs_prefix_format.format(get_option('libdir') / crt0_expr)
+ crt0_gen = gen_format.format(gen_crt0_path)
+ 
+@@ -686,10 +696,13 @@ if enable_multilib
+   buildtype_multilib_dir = specs_prefix_format.format(get_option('libdir') / '%*/%M')
+   multilib_buildtype = picolibc_buildtype_format.format(buildtype_multilib_dir)
+ 
++  sysroot_multilib_dir = '%*' + '/' + get_option('libdir') + '/' + '%*/%M'
++  multilib_sysroot = sysroot_format.format(sysroot_multilib_dir)
++  
+   gen_multilib_dir = specs_prefix_format.format(get_option('libdir') / '%M')
+   multilib_gen = gen_format.format(gen_multilib_dir)
+ 
+-  specs_multilibpath = '-L' + specs_option_format.format(multilib_prefix, multilib_buildtype, multilib_gen)
++  specs_multilibpath = '-L' + specs_option_format.format(multilib_prefix, multilib_buildtype, multilib_sysroot, multilib_gen)
+ 
+   #
+   # Prepend the multilib -L option to the non-multilib option
+@@ -705,6 +718,9 @@ if enable_multilib
+   buildtype_multilib_crt0_path = specs_prefix_format.format(get_option('libdir') / '%*/%M' / crt0_expr)
+   crt0_buildtype = picolibc_buildtype_format.format(buildtype_multilib_crt0_path)
+ 
++  sysroot_multilib_crt0_path = '%*' + prefix + '/' + get_option('libdir') + '/' + '/%M' + '/' + crt0_expr
++  crt0_sysroot = sysroot_format.format(sysroot_multilib_crt0_path)
++  
+   gen_multilib_crt0_path = specs_prefix_format.format(get_option('libdir') / '%M' / crt0_expr)
+   crt0_gen = gen_format.format(gen_multilib_crt0_path)
+ endif
+@@ -714,7 +730,7 @@ endif
+ # above. As there's only one value, it's either the
+ # multilib path or the non-multilib path
+ #
+-specs_startfile = specs_option_format.format(crt0_prefix, crt0_buildtype, crt0_gen)
++specs_startfile = specs_option_format.format(crt0_prefix, crt0_buildtype, crt0_sysroot, crt0_gen)
+ endif
+ 
+ specs_data = configuration_data()
diff --git a/meta/recipes-core/picolibc/picolibc/no-early-compiler-checks.cross b/meta/recipes-core/picolibc/picolibc/no-early-compiler-checks.cross
new file mode 100644
index 0000000000..87bfbad3c5
--- /dev/null
+++ b/meta/recipes-core/picolibc/picolibc/no-early-compiler-checks.cross
@@ -0,0 +1,6 @@
+# We need to explicitly bypass mesons sanity check to avoid early compiler errors
+# otherwise meson will try to compile AND run test applications:
+# ../git/meson.build:35:0: ERROR: Executables created by c compiler are not runnable...
+
+[properties]
+skip_sanity_check=true
\ No newline at end of file
diff --git a/meta/recipes-core/picolibc/picolibc_git.bb b/meta/recipes-core/picolibc/picolibc_git.bb
new file mode 100644
index 0000000000..fdb159328f
--- /dev/null
+++ b/meta/recipes-core/picolibc/picolibc_git.bb
@@ -0,0 +1,35 @@
+require picolibc.inc
+
+INHIBIT_DEFAULT_DEPS = "1"
+DEPENDS = "virtual/${TARGET_PREFIX}gcc"
+
+PROVIDES += "virtual/libc virtual/libiconv virtual/libintl"
+
+COMPATIBLE_HOST:libc-musl:class-target = "null"
+COMPATIBLE_HOST:libc-glibc:class-target = "null"
+COMPATIBLE_MACHINE = "qemuarm|qemuarm64|qemuriscv32|qemuriscv64"
+
+SRC_URI:append = " file://avoid_polluting_cross_directories.patch"
+SRC_URI:append = " file://no-early-compiler-checks.cross"
+
+# This is being added by picolibc meson files as well to avoid
+# early compiler tests from failing, cant remember why I added it
+# to the newlib recipe but I would assume it was for the same reason
+TARGET_CC_ARCH:append = " -nostdlib"
+
+# When using RISCV64 use medany for both C library and application recipes
+TARGET_CFLAGS:append:qemuriscv64 = " -mcmodel=medany"
+
+inherit meson
+
+MESON_CROSS_FILE:append = " --cross-file=${UNPACKDIR}/no-early-compiler-checks.cross"
+
+PACKAGECONFIG ??= " specsdir"
+# Install GCC specs on libdir
+PACKAGECONFIG[specsdir] = "-Dspecsdir=${libdir},-Dspecsdir=none"
+
+
+FILES:${PN}-dev:append = " ${libdir}/*.specs ${libdir}/*.ld"
+
+# No rpm package is actually created but -dev depends on it, avoid dnf error
+DEV_PKG_DEPENDENCY:libc-picolibc = ""