readme

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

#
#  $Id: README,v 1.3 2000/08/25 17:24:49 joel Exp $
#

This is a README file for the MBX860/MBX821 port of RTEMS 4.5.0

Please send any comments, improvements, or bug reports to:

Charles-Antoine Gauthier
[e-mail]

or

Darlene Stewart
[e-mail]
  
Software Engineering Group
Institute for Information Technology
National Research Council of Canada
Ottawa, ON, K1A 0R6
Canada  


Disclaimer
----------

The National Research Council of Canada is distributing this RTEMS
board support package for the Motorola MBX860 and MBX821 as free
software; you can redistribute it and/or modify it under terms of
the GNU General Public License as published by the Free Software
Foundation; either version 2, or (at your option) any later version.
This software is distributed in the hope that it will be useful, but
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 RTEMS; see file
COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,
Cambridge, MA 02139, USA.

Under no circumstances will the National Research Council of Canada
nor Her Majesty the Queen in right of Canada assume any liablility
for the use this software, nor any responsibility for its quality or
its support.


Summary
-------

BSP NAME:           mbx8xx
BOARD:              Motorola MBX860 and MBX821 Embedded Controllers
BUS:                No backplane. On-board ISA, PCI, PC/104 and PCMCIA.
CPU FAMILY:         PowerPC
CPU:                PowerPC MPC860 or MPC821
COPROCESSORS:       Built-in Motorola QUICC
MODE:               32 bit mode

DEBUG MONITOR:      EPPC-Bug

PERIPHERALS
===========
TIMERS:             PIT / Timebase
  RESOLUTION:       1 microsecond / frequency = clock-speed / 16
SERIAL PORTS:       2 or 4 SCCs (SCC1 is hardwired for Ethernet)
                    2 SMC
                    1 SIO
REAL-TIME CLOCK:    Many. Look at documentation.
DMA:                Each SCC and SMC.
VIDEO:              None on-board. MPC821 has a built-in LCD panel driver.
SCSI:               None on-board.
NETWORKING:         Ethernet (10 Mbps) on SCC1
		   

DRIVER INFORMATION
==================
CLOCK DRIVER:       yes
CONSOLE DRIVER:     yes
SHMSUPP:            N/A
TIMER DRIVER:       yes
NETWORK DRIVER:	    yes

NOTES
=====
On-chip resources:
	SCC1		network or console
	SCC2		serial port
	SMC1		gdb debug console/application console
	SMC2		application console
	CLK1		network
	CLK2		network
	CLK3
	CLK4
	CLK5
	CLK6
	CLK7
	CLK8
	BRG1		console
	BRG2		console
	BRG3		console
	BRG4		console
	RTC
	PIT		clock
	TB
	DEC
	SWT	
	*CS0		FLASH
	*CS1		DRAM bank (onboard)
	*CS2		DRAM bank 0 (1st half of DIMM)
	*CS3		DRAM bank 1 (2nd half of DIMM)
	*CS4		Battery-Backed SRAM
	*CS5		QSPAN PCI
	*CS6		QSPAN
	*CS7		Boot ROM
	UPMA
	UPMB
	IRQ0
	IRQ1
	IRQ2		
	IRQ3		
	IRQ4		
	IRQ5	
	IRQ6
	IRQ7
	IRQ_LVL0	
	IRQ_LVL1
	IRQ_LVL2
	IRQ_LVL3
	IRQ_LVL4
	IRQ_LVL5
	IRQ_LVL6
	IRQ_LVL7
	

Board description
-----------------
Clock rate:     50MHz Entry level boards, 40 MHz others.
Bus width:      8/32 bit Flash, 32 bit DRAM
FLASH:	        2-4MB, 120ns
RAM:            4-16MB EDO, 60ns DRAM DIMM


Installation
------------

All MBX821/MBX860 ports share the same source code base. The MPC821 does
not have SCC3 and SCC4. Instead, it has an LCD panel driver. Otherwise,
the MBX821 and MBX860 boards are essentially identical. Entry level boards
do not have all connectors and peripheral devices present. This has no
impact on the source code base; it merely means that some functionality
is not available on these entry level boards. For the most part, the port
uses the standard build process for powerpc targets. However, you must
specify the EXACT model of MBX board that you are building for as the
argument to the RTEMS_BSP make variable. If you do not, the build process
will build for a MBX860-002. Look at rtems/make/custom/mbx8xx.cfg for the
specific list of boards supported and their corresponding names. An
example build command is:

	make RTEMS_BSP=mbx821_001 VARIANT=DEBUG

This will build the debug version of all RTEMS libraries, samples and tests
(if the latter are enabled).

The Software Engineering Group of the Institute for Information Technology
only owns an MBX821-001 and MBX86-002. The only provided config files are
mbx821_001.cfg and mbx860_002.cfg. A SPECIFIC CONFIG FILE IS REQUIRED. Use
one of the provided files as a template to create a specific config file for
another model.
 
We rely on EPPC-BUG to download to the targets. We use the "PLH" command.
We enabled a TFTP deamon on our development host.


Port Description
Console driver
---------------

This BSP includes an termios-capable asynchronous serial line driver that
supports SMC1, SMC2, SCC2, and SCC3 and SCC4 if present. The RTEMS console is
selected in rtems/make/custom/mbx8xx.cfg with the CONSOLE_MINOR variable, or
in NVRAM if that option is enabled in the rtems/make/custom/mbx8xx.cfg file.
We normally run with the RTEMS application console on SMC2. SMC1 is used by
the debugger.

Support is provided for five different modes of operation:

  1. polled I/O done by EPPC-Bug with termios support,
  2. polled I/O done by EPPC-Bug without termios support,
  3. polled I/O done by the supplied device driver with termios support,
  4. polled I/O done by the supplied device driver without termios support,
  5. interrupt-driven I/O done by the supplied device driver with termios
     support.
     
If NVRAM_CONFIGURE is set to 1 in rtems/make/custom/mbx8xx.cfg, the mode of
operation of the driver is determined at boot time from the values stored
in the user area in NVRAM. See the Configuration Parameters section below for
instructions on setting up NVRAM. Otherwise, the mode of operation of the
serial driver is determined at build time in part by the value of the
UARTS_IO_MODE constant in rtems/make/custom/mbx8xx.cfg. Edit the file to select
the type of I/O desired before building RTEMS. The choices are:

  0 - polled I/O done by the supplied device driver,
  1 - interrupt-driven I/O done by the supplied device driver,
  2 - polled I/O done by EPPC-Bug.
  
Also, if NVRAM_CONFIGURE is not set to 1 in rtems/make/custom/mbx8xx.cfg, set
the value of UARTS_USE_TERMIOS to select whether termios should be used to
perform buffering and input/output processing. Without termios support, input
processing is limited to the substitution of LF for a received CR, and output
processing is limited to the transmission of a CR following the transmission of
a LF. The choices for UARTS_USE_TERMIOS are:

  0 - do not use termios
  1 - use termios

In most real-time applications, the driver should be configured to use
termios and interrupt-driven I/O. Special requirements may dictate otherwise.

Polled I/O must be used when running the timing tests. It must also be used
to run some other tests and some samples, such as the cdtest. Some tests
change the interrupt mask and will hang interrupt-driven I/O indefinitely.
Others, such as cdtest, perform console output from the static constructors
before the console is opened, causing the test to hang. Still other tests
produce output that is supposed to be in some specific order. For these
tests, termios should not be used, as termios buffers output and the
transmission of the buffers occur at somewhat unpredictable times.

The real solution is to fix the tests so that they work with interrupt-driven
I/O and termios.


printk() and debug output
-----------------------

The implementation of printk() in RTEMS is mostly independent of most system
services. The printk() function can therefore be used to print messages to a
debug console, particularly when debugging startup code or device drivers,
i.e. code that runs before the console driver is opened or that runs with
interrupts disabled.

Support is provided to send printk output to any port. Specify the desired
port at build time in rtems/make/custom/mbx8xx.cfg by setting the value
of PRINTK_MINOR to one of SMC1_MINOR, SMC2_MINOR, SCC2_MINOR, SCC3_MINOR,
or SCC4_MINOR. Alternatively, if NVRAM_CONFIGURE is set to 1 in
rtems/make/custom/mbx8xx.cfg, the printk port is selected based on data that
is stored in the user area in NVRAM. See the Configuration Parameters section
below for instructions on setting up NVRAM. 

Select the type of output desired for printk() by setting the value of
PRINTK_IO_MODE in rtems/make/custom/mbx8xx.cfg. The choices are:

  0 - polled I/O done by the supplied device driver,
  1 - polled I/O done by the supplied device driver,
  2 - polled I/O done by EPPC-Bug.
  
printk() does not use termios.

If the printk() port is opened by RTEMS, then PRINK_IO_MODE mode must have
the same value as UARTS_IO_MODE, otherwise the I/O functions will be in
conflict. Interrupt-driven printk() output did not work, although we think
that it should have. It would have been of dubious value anyways. If
interrupt-driven I/O is selected (value of 1), the driver defaults to using
polled I/O through the RTEMS driver.

IMPORTANT: Polled I/O through the RTEMS driver requires that the driver be