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@@ -112,3 +112,59 @@ Shell> FS0:\Image root=/dev/sda<X> rw console=ttyAMA0,115200n8
 References:
 1) https://www.kernel.org/doc/Documentation/efi-stub.txt
 2) http://www.uefi.org/specifications
+
+III. How to Run 32-bit Applications on aarch64
+==============================================
+
+Since multilib is not yet available for aarch64, this BSP offers some alternatives
+in order to run 32-bit legacy applications on an aarch64.
+
+Each method that helps to setup the environment to run 32-bit applications requires
+a few extra tools. Two of those metods are described in this section, one requiring
+chroot and another one qemu installation.
+
+meta-seattle BSP includes two scripts that help you to setup environment for 32bit
+applications that can be found under following path meta-seattle/recipes-support/32b-env/
+
+III.1 Using chroot tool to run 32-bit applications on aarch64
+=============================================================
+
+This solution requires the chroot tool on the target, a 32b-built rootfs, and
+a build for the seattle machine.
+
+root@seattle:~# scp <user>@<host_ip>:/homes/rootfs32b.tar.gz ./
+
+root@seattle:~# tar -zxf rootfs32.tar.gz
+
+root@seattle:~# set_32b_env_chroot.sh -r ./rootfs32
+
+# 32b environment started
+@seattle:~# ./hello32d
+
+Starting from this point, any 32-bit application can be executed, but not 64-bit
+applications which will fail due to wrong path to 32-bit libraries. To run a 64-bit
+application, chroot mode must be quit by using the "exit" command.
+
+III.2 Using qemu to run 32-bit applications on aarch64
+======================================================
+
+This example requires an existing 32b-built rootfs and a build for the seattle machine.
+It is also expected that qemu-arm is already installed!!!
+
+root@seattle:~# scp <user>@<host_ip>:/homes/rootfs32b.tar.gz ./
+
+root@seattle:~# source /usr/bin/set_32b_env_qemu.sh -r ./rootfs32
+
+Starting from this point, any 32-bit or 64-bit application can be executed.
+
+IV. Limitations
+===============
+In order to enable 32-bit support in the aarch64 kernel, COMPAT mode is enabled
+(CONFIG_COMPAT=y), page size set to 4K, and VirtualAddress set to 48-bit.
+
+It might be possible to use 64K page sizes and 42-bit VirtualAddress if it is possible
+to rebuild the 32-bit application using binutils version 2.25.
+
+If 32-bit support is not required, COMPAT mode can be disabled (CONFIG_COMPAT=n) and
+page sizes set to 64K and VirtualAddress to 42-bit. Any change of the kernel
+confguration requires of course a kernel rebuild.