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README.md

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+grub2-bhyve
+===========
+
+The following packages are required to build:
+* gcc (installs gcc48)
+* flex
+* bison
+* gmake
+
+Optionally:
+* gdb78 (for debugging)
+
+The configure command line is:
+
+    ./configure --with-platform=emu CC=gcc48 LEX=/usr/local/bin/flex \
+        --enable-grub-mount=no --enable-grub-mkfont=no \
+	--enable-grub-emu-sdl=no --disable-nls --disable-werror
+
+Running gmake will create a binary, grub-emu, in the grub-core directory.
+
+The command syntax is
+
+    grub-emu -r <root-dev> -m <device.map file> [-n] -M <guest-mem> <vmname>
+
+The device.map file is a text file that describes the mappings between
+grub device names and the filesystem images on the host e.g.
+
+    (cd0)  /images/centos.iso
+    (hd1)  /images/ubuntu-disk.img
+
+There is an additional device, "(host)", that is always available and
+allows the host filesystem to be accessed.
+
+The -r parameter takes a device name from the device.map file which
+will be used as the device for pathnames without a device specifier.
+
+The -M parameter specifies the amount of bhyve guest memory in MBytes.
+
+The -n parameter disables auto-insertion of "console=ttyS0" to the
+ start of the Linux kernel command-line.
+
+To boot a linux kernel, the 'linux' command is used to load the kernel
+and specify command-line options, while the 'initrd' command is used
+to load the initrd. The 'boot' command is then issued to finalize 
+loading, set bhyve register state, and exit grub-emu.
+grub-emu will auto-insert a "console=ttyS0" line if there isn't one
+present in the command line. This can be disabled by passing the
+'-n' option to grub-emu.
+
+    linux  /isolinux/vmlinuz text earlyprintk=serial debug
+    initrd /isolinux/initrd.img
+    boot
+
+For OpenBSD i386/amd64, the command to load the kernel is 'kopenbsd'. The
+"-h com0" option forces the use of the serial console - this should always
+be used with bhyve. The root device is specified with the "-r <sdX|wdX>"
+parameter.
+
+    kopenbsd -h com0 -r sd0a /bsd
+    boot
+
+NetBSD/amd64 is booted with the 'knetbsd' command. Similar to OpenBSD,
+the "-h" and "-r" parameters should be used to specify a serial console
+and the root device.
+
+    knetbsd -h -r cd0a /netbsd
+    boot 
+
+FreeBSD/amd64 can be booted using the kfreebsd command. Note that
+grub will not automatically source any of the FreeBSD loader variable
+files, or interpret these as the FreeBSD loader does. The boot process
+will have to be manual unless a grub.cfg file has been created.
+
+    kfreebsd -h /boot/kernel/kernel
+    kfreebsd_loadenv /boot/device.hints
+    boot
+