diff --git a/doc/FU540-C000-v1.0.pdf b/doc/FU540-C000-v1.0.pdf deleted file mode 100644 index 1a8cc69..0000000 Binary files a/doc/FU540-C000-v1.0.pdf and /dev/null differ diff --git a/doc/riscv-calling.pdf b/doc/riscv-calling.pdf deleted file mode 100644 index a3351b1..0000000 Binary files a/doc/riscv-calling.pdf and /dev/null differ diff --git a/doc/riscv-privileged-20190608-1.pdf b/doc/riscv-privileged-20190608-1.pdf deleted file mode 100644 index 2303a01..0000000 Binary files a/doc/riscv-privileged-20190608-1.pdf and /dev/null differ diff --git a/doc/riscv-spec-20191213.pdf b/doc/riscv-spec-20191213.pdf deleted file mode 100644 index 533c1cb..0000000 Binary files a/doc/riscv-spec-20191213.pdf and /dev/null differ diff --git a/doc/virtio-v1.1-csprd01.pdf b/doc/virtio-v1.1-csprd01.pdf deleted file mode 100644 index c7be62b..0000000 Binary files a/doc/virtio-v1.1-csprd01.pdf and /dev/null differ