

Board Overview
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This is an early release of the Linux port to the ADI BRH platform

The BRH is an evaluation platform for ADI Engineering's 80200BECC
(Big-Endian Companion Chip) chipset for the Intel 80200 XScale CPU.
The 80200BECC is a follow on product to the 80200FCC and provides a
functioning PCI unit, high performance memory controller, DMA units,
and two timers.

Port Status
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Supported:

 - Little and Big Endian operation
 - Dual Ethernets 
 - Both serial ports
 - Flash access to MTD
 - On board PCI slot

Unsupported:

 - XScale PMU as it is being used for the timer source
 - On Board DMA

Building the Kernel
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  make distclean
  make brh_be_config oldconfig dep
  make zImage

If running in little endian mode, replace brh_be_config with brh_config.

When done, the new zImage will be in arch/arm/boot/zImage

Loading Linux
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Configure your com program to 57600, N81

I'm assuming that you are using RedBoot as your bootloader, and not 
anything else. Once redboot is started:

   RedBoot> load -r -b 0xc1008000 -m y

Now start a y-modem transfer of the zImage file in your com program.

Once completed:

   RedBoot> go 0xc1008000
   Uncompressing Linux.......booting kernel
   Linux version 2.4.18-rmk6 (dsaxena@xanadu.az.mvista.com) (gcc version 2. 95.3 20010315 (release/MontaVista)) #8 Thu May 23 10:24:49 MST 2002             
    CPU: Intel XScale-80200 revision 1                                
    Machine: ADI BRH                                                    
    On node 0 totalpages: 8192                                             
    zone(0): 8192 pages.                                                      
    zone(1): 0 pages.                                                         
    zone(2): 0 pages.  
    ...

Notes/Issues
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PCI Windows and available RAM

  The current port only allows linux to use 32 out of the 128MB 
  available on the board.  The reason for this is that the inbound
  PCI windows on the BECC only allow for 2 separate 32MB windows,
  not a single 128MB window.  This put several limitations on
  the way drivers can allocate buffers for use by PCI, so it is
  much easier to limit linux than to hack all the drivers.  It may
  be possible to use the higmem stuff to use the upper 96MB of memory
  only for user and vmalloc space, but I haven't had a chance to look
  at that yet.

MTD on the BRH board

  There are several different ways to use MTD on the BRH board.
  If you turn on CONFIG_MTD_CONCAT (off in the default config),
  the driver will concatanate all available flash banks into a
  single contigous regions and create two partitions (firmware,
  and user access).  You can change the partioning scheme if you 
  wish by editing the file drivers/mtd/maps/brh.c.

  If you do not turn on MTD concatanation support, the driver will
  split the boot flash device into two regions (firmware & user)
  and then create a single partition on each user flash device.

