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+This directory contains board specific code for a generic MPC860T based
+embedded computer, called 'GEN860T'.  The design is generic in the sense that
+common, readily available components are used and that the architecture of the
+system is relatively straightforward:
+
+	One eight bit wide boot (FLASH) memory
+	32 bit main memory using SDRAM
+	DOC 2000+
+	Ethernet PHY
+	Some I2C peripheral devices: Atmel AT24C256 EEPROM, Maxim DS1337 RTC.
+	Some other miscellaneous peripherals
+
+NOTE: There are references to a XIlinx FPGA and Mil-Std 1553 databus in this
+port.  I guess the computer is not as generic as I first said 8)  However,
+these extras can be safely ignored.
+
+Given the GEN860T files, it should be pretty easy to reverse engineer the
+hardware configuration, if that's useful to you.  Hopefully, this code will
+be useful to someone as a basis for a port to a new system or as a head start
+on a custom design.  If you end up using any of this, I would appreciate
+hearing from you, especially if you discover bugs or find ways to improve the
+quality of this U-Boot port.
+
+Here are the salient features of the system:
+Clock						:	33.3 Mhz oscillator
+Processor core frequency	:	66.6 Mhz  if in 1:2:1 mode; can also run 1:1
+Bus frequency				:	33.3 Mhz
+
+Main memory:
+	Type	: SDRAM
+	Width	: 32 bits
+	Size	: 64 mibibytes
+	Chip	: Two Micron MT48LC16M16A2TG-7E
+	CS		: MPC860T CS1*/UPMA
+	UPMA CONNECTIONS:
+		SDRAM A10	: GPLA0*
+		SDRAM CAS*	: GPLA2*
+		SDRAM WE*	: GPLA3*
+		SDRAM RAS*	: GPLA4*
+
+Boot memory:
+	Type	: FLASH
+	Width	: 8 bits
+	Size	: 16 mibibytes
+	Chip	: One Intel 28F128J3A (StrataFlash)
+	CS		: MPC860T CS0*/GPCM (this is the "boot" chip select)
+
+EEPROM memory:
+	Type	: Serial I2C EEPROM
+	Width	: 8 bits
+	Size	: 32 kibibytes
+	Chip	: One Atmel AT25C256
+	CS		: 0x50 (external I2C address pins on device are tied to GND)
+
+Filesystem memory:
+	Type	: NAND FLASH (Toshiba)
+	Width	: 8 bits (i.e. interface to DOC is 8 bits)
+	Size	: 32 mibibytes
+	Chip	: One DiskOnCHip Millenium Plus (DOC 2000+)
+	CS		: MPC860T CS2*/GPCM
+
+Network support:
+	MAC		: MPC86OT FEC (Fast Ethernet Controller)
+	PHY		: Intel LXT971A
+	MII Addr: 0x0 (hardwired on the board)
+	MII IRQ	:
+
+Console:
+	RS-232 on SMC1 (Maxim MAX3232 LVCMOS-RS232 level shifter)
+
+Real Time Clock:
+	Type	: Low power, I2C interface
+	Chip	: Maxim DS1337
+	CS		: Address 0x68 on I2C bus
+
+	The MPC860T's internal RTC has a defect in Mask rev D that increases
+	the current drain on the KAPWR line to 10 mA.  Since this is an
+	unreasonable amount of current draw for a RTC, and Motorola does not
+	plan to fix this in future mask revisions, a serial (I2C) RTC that
+	works has been included instead.  NOTE that the DS1337 can be
+	configured to output a 32768 Hz clock while the main power is on.
+	This clock output has been routed to the MPC860T's EXTAL pin to allow
+	the internal RTC to be used.  NOTE also that due to yet another
+	defect in the rev D mask, the RTC does not operate reliably when the
+	internal RTC divisor is set to use a 32768 Hz reference.  So just use
+	the I2C RTC.
+
+Miscellaneous:
+	Xilinx Virtex FPGA on CS3*/GPCM.
+	Virtex FPGA slave SelectMap interface on cs4*/UPMB.
+	Mil-Std 1553 databus interface on CS5*/GPCM.
+	Audio sounder (beeper) with digital volume control connected to SPKROUT.
+
+SC variant:
+	A reduced-feature version of the GEN860T port is also supported: GEN860T_SC.
+	The 'SC' variant only provides support for the Virtex FPGA, SDRAM main
+	memory, EEPROM and flash memory.  The system clock frequency is reduced
+	to 24 MHz.
+
+Issues:
+	The DOC 2000+ returns 0x40 as its device ID when probed using the method
+	desxribed in the DOC datasheet.  Unfortunately, the U-Boot DOC driver
+	does not recognize this device.  As of this writing, it seems that MTD
+	does not support the DOC 2000+ either.
+
+Status:
+	Everything appears to work except DOC support. As of this writing,
+	David Woodhouse has stated on the MTD mailing list that he has no
+	knowledge of the DOC Millineum Plus and therfore there is no support
+	in MTD for this device.  I wish I had known this sooner :(
+
+The GEN860T board specific files and configuration is based on the work
+of others who have contributed to U-Boot. The copyright and license notices
+of these authors have been retained wherever their code has been reused.
+All new code to support the GEN860T board is:
+
+	(C) Copyright 2001-2003
+	Keith Outwater (keith_outwater@mvis.com)
+
+and the following license applies:
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of
+the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+MA 02111-1307 USA
+
+Thanks to Wolfgang Denk for a great software package and to everyone
+who contributed to its development.
+
+Keith Outwater
+Sr. Staff Engineer
+Microvision, Inc.
+<keith_outwater@mvis.com>
+<outwater@eskimo.com>
+
+vim: set ts=4 sw=4 tw=78: