SDL: Add documentation for KMSDRM on *BSDs

From 350e0ae1fd2ee54a3549ddf57833993d106a75f6 Mon Sep 17 00:00:00 2001
From: Cacodemon345 <[EMAIL REDACTED]>
Date: Mon, 15 Feb 2021 23:49:57 +0600
Subject: [PATCH] Add documentation for KMSDRM on *BSDs

---
 docs/README-kmsbsd.md | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 docs/README-kmsbsd.md

diff --git a/docs/README-kmsbsd.md b/docs/README-kmsbsd.md
new file mode 100644
index 000000000..54bb785b2
--- /dev/null
+++ b/docs/README-kmsbsd.md
@@ -0,0 +1,30 @@
+KMSDRM on *BSD
+==================================================
+
+KMSDRM is supported on FreeBSD and OpenBSD. DragonFlyBSD is not tested yet, but should work. NetBSD isn't supported yet because the application will crash when creating the KMSDRM screen.
+
+WSCONS support has been brought back, but only as an input backend. It will not be brought back as a video backend to ease maintenance.
+
+OpenBSD note: Note that the video backend assumes that the user has read/write permissions to the /dev/drm* devices.
+
+
+===================================================
+SDL2 WSCONS input backend features
+===================================================
+1. It is keymap-aware; it will work properly with different keymaps.
+2. It has mouse support.
+3. Accent input is supported.
+4. Compose keys are supported.
+5. AltGr and Meta Shift keys work as intended.
+
+==================================================
+Partially working or no input on OpenBSD/NetBSD.
+==================================================
+
+The WSCONS input backend needs read/write access to the /dev/wskbd* devices, without which it will not work properly. /dev/wsmouse must also be read/write accessible, otherwise mouse input will not work.
+
+==================================================
+Partially working or no input on FreeBSD.
+==================================================
+
+The evdev devices are only accessible to the root user by default. Edit devfs rules to allow access to such devices. The /dev/kbd* devices are also only accessible to the root user by default. Edit devfs rules to allow access to such devices.