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Tsi620 Evaluation Board User Manual
60D7000_MA001_03
Intergrated Device Technology
www.idt.com
The RapidIO device access driver (rio-dev.ko) is another kernel module that allows for user space
applications to communicate with RapidIO devices. This driver allows special device files (in the /dev
directory of the system) to be created and used to access RapidIO devices as if they were simply a file.
The driver works with any RapidIO host that implements a specific set of kernel interfaces; however,
the only known driver that implements these interfaces is the Tsi620 driver. For example, the RapidIO
port built into the Freescale 8548 could potentially be accessed through this driver, however the
Freescale driver would have to be modified to support the device access routines. Because the driver
depends on the RapidIO system being enumerated, this driver must be loaded after the RapidIO
hardware driver. As the Tsi620 driver may only be loaded from a binary module after boot, the device
access driver should also be compiled as a binary module and loaded after the Tsi620 driver. This
driver may be released under the GPL, and the source code is included with the Linux kernel code on
the companion CD for Tsi620 evaluation board.
The user space applications demonstrate access of RapidIO devices using the device access driver
described above. The applications communicate with the DSP (or FPGA) to demonstrate correct
operation of the Tsi620 driver. There are two included applications:
•
memdump – This accesses the memory of an endpoint and displays its memory contents
•
askdsp – This communicates with a program executing on a DSP to perform a calculation
Although both applications are relatively simple, they demonstrate that the RapidIO devices are
accessible and useful from user space. This means that much more complex applications may be built
using RapidIO resources to extend and enhance the system’s capabilities. The user space applications
are provided in pre-compiled binary form on the EP8343 ramdisk image, or in both pre-compiled and
source code form on the EP8343 NFS image (both which can be found on the companion CD for the
Tsi620 evaluation board).
2.1.1
Running the Software Using Ramdisk
1. Ensure the serial cable is connected to the PMC’s RS-232 port using an RJ-45 cable and an RJ-45
to DB9 adapter.
2. Start the terminal program of your choice.
IDT has had success using the TeraTerm software although other terminal emulation programs can
be used (for information about the TeraTerm software, see hp.vector.co.jp/authors/VA002416/
teraterm.html). The terminal program should be configured to communicate 115200 bps with 8
data bits, 1 stop bit, and no parity bits.
3. Power up the Tsi620 evaluation board by connecting the power adapter, and setting the toggle
switch to the “on” position.
The U-Boot boot loader software should start and a prompt should appear on the terminal program.
4. Enter the command
run rd
.
This command boots the Linux kernel stored in flash. The Linux kernel uses a ramdisk stored in
flash as the file system.
5. Log in to the system as “root”; no password is required.
From the shell prompt you are presented with, enter the command
cd /root
to get to the root
user's home directory.