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+/*
+ * (C) Copyright 2000
+ * Dave Ellis, SIXNET, dge@sixnetio.com
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+Using the Motorola MPC8XXFADS development board
+===============================================
+
+CONFIGURATIONS
+--------------
+
+There are ready-to-use default configurations available for the
+FADS823, FADS850SAR and FADS860T. The FADS860T configuration also
+works for the 855T processor.
+
+LOADING U-Boot INTO FADS FLASH MEMORY
+--------------------------------------
+
+MPC8BUG can load U-Boot into the FLASH memory using LOADF.
+
+ loadf u-boot.srec 100000
+
+
+STARTING U-Boot FROM MPC8BUG
+-----------------------------
+
+To start U-Boot from MPC8BUG:
+
+1. Reset the board:
+ reset :h
+
+2. Change BR0 and OR0 back to their values at reset:
+ rms memc br0 00000001
+ rms memc or0 00000d34
+
+3. Modify DER so MPC8BUG gets control only when it should:
+ rms der 2002000f
+
+4. Start as if from reset:
+ go 100
+
+This is NOT exactly the same as starting U-Boot without
+MPC8BUG. MPC8BUG turns off the watchdog as part of the hard reset.
+After it does the reset it writes SYPCR (to disable the watchdog)
+and sets BR0 and OR0 to map the FLASH at 0x02800000 (and does lots
+of other initialization). That is why it is necessary to set BR0
+and OR0 to map the FLASH everywhere. U-Boot can't turn on the
+watchdog after that, since MPC8BUG has used the only chance to write
+to SYPCR.
+
+Here is a bizarre sequence of MPC8BUG and U-Boot commands that lets
+U-Boot write to SYPCR. It works with MPC8BUG 1.5 and an 855T
+processor (your mileage may vary). It is probably better (and a lot
+easier) just to accept having the watchdog disabled when the debug
+cable is connected.
+
+in MPC8BUG:
+ reset :h
+ rms memc br0 00000001
+ rms memc or0 00000d34
+ rms der 2000f
+ go 100
+
+Now U-Boot is running with the MPC8BUG value for SYPCR. Use the
+U-Boot 'reset' command to reset the board.
+ =>reset
+Next, in MPC8BUG:
+ rms der 2000f
+ go
+
+Now U-Boot is running with the U-Boot value for SYPCR.