[PATCH] doc: build: update description of build dependencies for Alpine Linux

[Milan P. Stanić]

---
 doc/build/gcc.rst | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/doc/build/gcc.rst b/doc/build/gcc.rst
index a0650a51db..e73f24a304 100644
--- a/doc/build/gcc.rst
+++ b/doc/build/gcc.rst
@@ -60,8 +60,28 @@ For building U-Boot on Alpine Linux at least the following packages are needed:
 
 .. code-block:: bash
 
-    apk add alpine-sdk bc bison dtc flex linux-headers ncurses-dev \
-      openssl-dev perl python3 py3-setuptools python3-dev sdl2-dev
+    apk add alpine-sdk bc bison dtc flex gnutls-dev linux-headers \
+      openssl-dev py3-elftools py3-setuptools python3-dev swig util-linux-dev
+
+Dependeing on the build target further packages may be needed
+
+For build sandbox with lcd
+
+.. code-block:: bash
+
+    apk add sdl2-dev
+
+For build riscv64 targets
+
+.. code-block:: bash
+
+    apk add opensbi
+
+For build some arm64 targets
+
+.. code-block:: bash
+
+    apk add arm-trusted-firmware
 
 Prerequisites
 -------------
-- 
2.42.0