[PATCH 5/5] bsp/xen: Update README

[Jeff Kubascik]

Add some background information on the BSP and instructions on how to
run the ticker application.
---
 bsps/arm/xen/README | 130 ++++++++++++++++++++++----------------------
 1 file changed, 64 insertions(+), 66 deletions(-)

diff --git a/bsps/arm/xen/README b/bsps/arm/xen/README
index 1b24d84c9a..2ae2f2170d 100644
--- a/bsps/arm/xen/README
+++ b/bsps/arm/xen/README
@@ -1,66 +1,64 @@
-#  This is a sample hardware description file for a BSP.  This comment
-#  block does not have to appear in a real one.  The intention of this
-#  file is to provide a central place to look when searching for
-#  information about a board when starting a new BSP.  For example,
-#  you may want to find an existing timer driver for the chip you are
-#  using on your board.  It is easier to grep for the chip name in
-#  all of the HARDWARE files than to peruse the source tree.  Hopefully,
-#  making the HARDDWARE files accurate will also alleviate the common
-#  problem of not knowing anything about a board based on its BSP
-#  name.
-#
-#  NOTE:  If you have a class of peripheral chip on board which
-#         is not in this list please add it to this file so
-#         others will also use the same name.
-#
-#         Timer resolution is the way it is configured in this BSP.
-#         On a counting timer, this is the length of time which
-#         corresponds to 1 count.
-#
-
-BSP NAME:           fastsbc1
-BOARD:              Fasssst Computers, Fast SBC-1
-BUS:                SchoolBus
-CPU FAMILY:         i386
-CPU:                Intel Hexium
-COPROCESSORS:       Witch Hex87
-MODE:               32 bit mode
-
-DEBUG MONITOR:      HexBug
-
-PERIPHERALS
-===========
-TIMERS:             Intel i8254
-  RESOLUTION:         .0001 microseconds
-SERIAL PORTS:       Zilog Z8530 (with 2 ports)
-REAL-TIME CLOCK:    RTC-4
-DMA:                Intel i8259
-VIDEO:              none
-SCSI:               none
-NETWORKING:         none
-
-DRIVER INFORMATION
-==================
-CLOCK DRIVER:       RTC-4
-IOSUPP DRIVER:      Zilog Z8530 port A
-SHMSUPP:            polled and interrupts
-TIMER DRIVER:       Intel i8254
-TTY DRIVER:         stub only
-
-STDIO
-=====
-PORT:               Console port 0
-ELECTRICAL:         RS-232
-BAUD:               9600
-BITS PER CHARACTER: 8
-PARITY:             None
-STOP BITS:          1
-
-NOTES
-=====
-
-(1) 900 Mhz and 950 Mhz versions.
-
-(2) 1 Gb or 2 Gb RAM.
-
-(3) PC compatible if HexBug not enabled.
+BSP for Xen on ARM
+
+Overview
+--------
+
+This BSP enables RTEMS to run as a guest virtual machine in AArch32 mode on the
+Xen hypervisor for ARMv8 platforms.
+
+Drivers:
+- Clock: ARMv7-AR Generic Timer
+- Console: Virtual PL011 device
+- Interrupt: GICv2
+
+BSP variants:
+- xen_virtual: completely virtualized guest with no dependence on underlying
+  hardware
+
+The xen_virtual BSP variant relies on standard Xen features, so it should be
+able to run on any ARMv8 platform.
+
+Xen allows for the passthrough of hardware peripherals to guest virtual
+machines. BSPs could be added in the future targeting specific hardware
+platforms and include the appropriate drivers.
+
+This BSP was tested with Xen running on the Xilinx Zynq UltraScale+ MPSoC using
+the Virtuosity distribution maintained by DornerWorks.
+
+Execution
+---------
+
+This procedure describes how to run the ticker sample application that should
+already be built with the BSP.
+
+The `ticker.exe` file can be found in the BSP build tree at:
+
+  arm-rtems5/c/xen_virtual/testsuites/samples/ticker.exe
+
+The `ticker.exe` elf file must be translated to a binary format.
+
+  arm-rtems5-objcopy -O binary ticker.exe ticker.bin
+
+Then place the `ticker.bin` file on the dom0 filesystem.
+
+From the dom0 console, create a configuration file `ticker.cfg` with the
+following contents.
+
+  name = "ticker"
+  kernel = "ticker.bin"
+  memory = 8
+  vcpus = 1
+  gic_version = "v2"
+  vuart = "sbsa_uart"
+
+Create the virtual machine and attach to the virtual vpl011 console.
+
+  xl create ticker.cfg && xl console -t vuart ticker
+
+To return back to the dom0 console, press both `Ctrl` and `]` on your keyboard.
+
+Additional information
+----------------------
+
+The Virtuosity distribution can be found at
+  https://dornerworks.com/xen/virtuosity
-- 
2.17.1