From a0035578bd889c4e10c827a8cc329f170848e5c6 Mon Sep 17 00:00:00 2001
From: R Veera Kumar <vklr@vkten.in>
Date: Mon, 24 May 2021 13:52:12 +0530
Subject: [PATCH] Add pages for GHDL setup and use.

---
 HDL_workflow.mdwn      | 12 ++++++++
 HDL_workflow/ghdl.mdwn | 63 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 HDL_workflow/ghdl.mdwn

diff --git a/HDL_workflow.mdwn b/HDL_workflow.mdwn
index 92928bfdf..d3b2a5b72 100644
--- a/HDL_workflow.mdwn
+++ b/HDL_workflow.mdwn
@@ -546,6 +546,18 @@ Advise use only v4.106 at the moment.
 
 See [[HDL_workflow/verilator]] page for installation instructions.
 
+## GHDL
+
+GHDL is a shorthand for G Hardware Design Language. It is a VHDL analyzer, compiler, simulator and (experimental) synthesizer that can process (nearly) any VHDL design.
+
+VHDL is an acronym for Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (HDL), which is a programming language used to describe a logic circuit by function, data flow behavior, or structure.
+
+Unlike some other simulators, GHDL is a compiler: it directly translates a VHDL file to machine code, without using an intermediary language such as C or C++. Therefore, the compiled code should be faster and the analysis time should be shorter than with a compiler using an intermediary language.
+
+GHDL aims at implementing VHDL as defined by IEEE 1076. It supports the 1987, 1993 and 2002 revisions and, partially, 2008. PSL is also partially supported.
+
+See [[HDL_workflow/ghdl]] page for installation instructions.
+
 # Registering for git repository access
 
 After going through the onboarding process and having agreed to take
diff --git a/HDL_workflow/ghdl.mdwn b/HDL_workflow/ghdl.mdwn
new file mode 100644
index 000000000..f95f7aae6
--- /dev/null
+++ b/HDL_workflow/ghdl.mdwn
@@ -0,0 +1,63 @@
+# Installation instructions for GHDL
+
+## Setting up new debootstrap and chroot into it
+
+Run the following if you wish to isolate the ghdl build
+from other software (reproducible builds) or use the schroot
+auto-preparation script here:
+<https://git.libre-soc.org/?p=dev-env-setup.git;a=blob;f=mk-deb-chroot;hb=HEAD>
+
+    export MY_CHROOT=/stable-chroot
+    mkdir $MY_CHROOT
+    debootstrap stable $MY_CHROOT http://deb.debian.org/debian/
+    mount -t proc proc $MY_CHROOT/proc
+    mount -t sysfs sysfs $MY_CHROOT/sys
+    mount -t devpts devpts $MY_CHROOT/dev/pts/
+    chroot $MY_CHROOT /bin/bash
+
+## Steps to compile GHDL
+
+### Necessary software to install
+
+    apt-get install git gnat gcc make g++ file texinfo zlib1g-dev
+
+    git clone https://github.com/ghdl/ghdl.git
+    wget https://ftp.gnu.org/gnu/gmp/gmp-6.2.1.tar.xz
+    wget https://ftp.gnu.org/gnu/mpc/mpc-1.2.1.tar.gz
+    wget https://www.mpfr.org/mpfr-4.1.0/mpfr-4.1.0.tar.xz
+    wget https://gcc.gnu.org/pub/gcc/infrastructure/isl-0.18.tar.bz2
+    wget https://ftp.gnu.org/gnu/gcc/gcc-10.3.0/gcc-10.3.0.tar.xz
+
+### Build GHDL
+
+    tar -xf gcc-10.3.0.tar.xz
+    cd gcc-10.3.0
+    tar -xf ../gmp-6.2.1.tar.xz
+    mv gmp-6.2.1 gmp
+    tar -xf ../mpc-1.2.1.tar.gz
+    mv mpc-1.2.1 mpc
+    tar -xf ../mpfr-4.1.0.tar.xz
+    mv mpfr-4.1.0 mpfr
+    tar -xf ../isl-0.18.tar.bz2
+    mv isl-0.18 isl
+    cd ..
+
+    cd ghdl
+    git checkout v1.0.0
+    mkdir build
+    cd build
+    ../configure --with-gcc=../../gcc-10.3.0 --prefix=/usr/local/ghdl
+    make copy-sources
+    mkdir gcc-objs; cd gcc-objs
+    ../../../gcc-10.3.0/configure --prefix=/usr/local/ghdl \
+    --enable-languages=c,vhdl --disable-bootstrap --disable-lto \
+    --disable-multilib --disable-libssp --disable-libgomp \
+    --disable-libquadmath --enable-default-pie
+    make -j$(nproc)
+    make install
+    cd ..
+    make ghdllib
+    make install
+
+Please adjust the install paths for ghdl.
+
-- 
2.30.2