diff --git a/doc/building.html b/doc/building.html index e90669aa864..f1f9047808b 100644 --- a/doc/building.html +++ b/doc/building.html @@ -134,6 +134,8 @@ id="toc-cross-compiling-with-debian-sysroots">Cross compiling with Debian sysroots
  • Building for ARM/aarch64
    • +
  • Building +for RISC-V
  • Building for musl

  • Fortunately, you can create sysroots for foreign architectures with tools provided by your OS. On Debian/Ubuntu systems, one could use -qemu-deboostrap to create the target system -chroot, which would have the native libraries and headers specific to -that target system. After that, we can use the cross-compiler -on the build system, pointing into chroot to get the build +debootstrap to create the target system chroot, +which would have the native libraries and headers specific to that +target system. After that, we can use the cross-compiler on the +build system, pointing into chroot to get the build dependencies right. This allows building for foreign architectures with native compilation speed.

    For example, cross-compiling to AArch64 from x86_64 could be done @@ -1389,7 +1391,7 @@ like this:

    apt install g++-aarch64-linux-gnu gcc-aarch64-linux-gnu

  • Create chroot on the build system, configuring it for target system: -sudo qemu-debootstrap \ --arch=arm64 \ --verbose \ --include=fakeroot,symlinks,build-essential,libx11-dev,libxext-dev,libxrender-dev,libxrandr-dev,libxtst-dev,libxt-dev,libcups2-dev,libfontconfig1-dev,libasound2-dev,libfreetype6-dev,libpng-dev,libffi-dev \ --resolve-deps \ buster \ ~/sysroot-arm64 \ http://httpredir.debian.org/debian/

    • +sudo debootstrap \ --arch=arm64 \ --verbose \ --include=fakeroot,symlinks,build-essential,libx11-dev,libxext-dev,libxrender-dev,libxrandr-dev,libxtst-dev,libxt-dev,libcups2-dev,libfontconfig1-dev,libasound2-dev,libfreetype6-dev,libpng-dev,libffi-dev \ --resolve-deps \ buster \ ~/sysroot-arm64 \ http://httpredir.debian.org/debian/ # If the target architecture is `riscv64`, # the path should be `debian-ports` instead of `debian`.

  • Make sure the symlinks inside the newly created chroot point to proper locations: sudo chroot ~/sysroot-arm64 symlinks -cr .

    • @@ -1516,6 +1518,13 @@ are:

    sh4-linux-gnu zero + +riscv64 +sid +riscv64 +riscv64-linux-gnu +(all) +

    Building for ARM/aarch64

    @@ -1525,6 +1534,21 @@ profiles are available using --with-abi-profile: arm-vfp-sflt, arm-vfp-hflt, arm-sflt, armv5-vfp-sflt, armv6-vfp-hflt. Note that soft-float ABIs are no longer properly supported by the JDK.

    +

    Building for RISC-V

    +

    The RISC-V community provides a basic GNU compiler +toolchain, but the external +libraries required by OpenJDK complicate the building process. The +placeholder <toolchain-installed-path> shown below is +the path where you want to install the toolchain.

    +

    Building for musl

    Just like it's possible to cross-compile for a different CPU, it's possible to cross-compile for musl libc on a glibc-based build diff --git a/doc/building.md b/doc/building.md index 65ff7509a38..142ff7daf36 100644 --- a/doc/building.md +++ b/doc/building.md @@ -1147,7 +1147,7 @@ Note that X11 is needed even if you only want to build a headless JDK. ### Cross compiling with Debian sysroots Fortunately, you can create sysroots for foreign architectures with tools -provided by your OS. On Debian/Ubuntu systems, one could use `qemu-deboostrap` to +provided by your OS. On Debian/Ubuntu systems, one could use `debootstrap` to create the *target* system chroot, which would have the native libraries and headers specific to that *target* system. After that, we can use the cross-compiler on the *build* system, pointing into chroot to get the build dependencies right. This allows building @@ -1162,7 +1162,7 @@ For example, cross-compiling to AArch64 from x86_64 could be done like this: * Create chroot on the *build* system, configuring it for *target* system: ``` - sudo qemu-debootstrap \ + sudo debootstrap \ --arch=arm64 \ --verbose \ --include=fakeroot,symlinks,build-essential,libx11-dev,libxext-dev,libxrender-dev,libxrandr-dev,libxtst-dev,libxt-dev,libcups2-dev,libfontconfig1-dev,libasound2-dev,libfreetype6-dev,libpng-dev,libffi-dev \ @@ -1170,6 +1170,8 @@ For example, cross-compiling to AArch64 from x86_64 could be done like this: buster \ ~/sysroot-arm64 \ http://httpredir.debian.org/debian/ + # If the target architecture is `riscv64`, + # the path should be `debian-ports` instead of `debian`. ``` * Make sure the symlinks inside the newly created chroot point to proper locations: @@ -1217,6 +1219,7 @@ Architectures that are known to successfully cross-compile like this are: m68k sid m68k m68k-linux-gnu zero alpha sid alpha alpha-linux-gnu zero sh4 sid sh4 sh4-linux-gnu zero + riscv64 sid riscv64 riscv64-linux-gnu (all) ### Building for ARM/aarch64 @@ -1226,6 +1229,44 @@ available using `--with-abi-profile`: arm-vfp-sflt, arm-vfp-hflt, arm-sflt, armv5-vfp-sflt, armv6-vfp-hflt. Note that soft-float ABIs are no longer properly supported by the JDK. +### Building for RISC-V + +The RISC-V community provides a basic +[GNU compiler toolchain](https://github.com/riscv-collab/riscv-gnu-toolchain), +but the [external libraries](#External-Library-Requirements) required by OpenJDK +complicate the building process. The placeholder `` +shown below is the path where you want to install the toolchain. + + * Install the RISC-V GNU compiler toolchain: + ``` + git clone --recursive https://github.com/riscv-collab/riscv-gnu-toolchain + cd riscv-gnu-toolchain + ./configure --prefix= + make linux + export PATH=/bin:$PATH + ``` + + * Cross-compile all the required libraries: + ``` + # An example for libffi + git clone https://github.com/libffi/libffi + cd libffi + ./configure --host=riscv64-unknown-linux-gnu --prefix=/sysroot/usr + make + make install + ``` + + * Configure and build OpenJDK: + ``` + bash configure \ + --with-boot-jdk=$BOOT_JDK \ + --openjdk-target=riscv64-linux-gnu \ + --with-sysroot=/sysroot \ + --with-toolchain-path=/bin \ + --with-extra-path=/bin + make images + ``` + ### Building for musl Just like it's possible to cross-compile for a different CPU, it's possible to