Skip to content
Projects
Groups
Snippets
Help
Loading...
Sign in
Toggle navigation
S
SDB - Self-describing Bus
Project
Project
Details
Activity
Cycle Analytics
Repository
Repository
Files
Commits
Branches
Tags
Contributors
Graph
Compare
Charts
Issues
0
Issues
0
List
Board
Labels
Milestones
Merge Requests
0
Merge Requests
0
Wiki
Wiki
image/svg+xml
Discourse
Discourse
Members
Members
Collapse sidebar
Close sidebar
Activity
Graph
Charts
Create a new issue
Commits
Issue Boards
Open sidebar
Projects
SDB - Self-describing Bus
Commits
3fb49318
Commit
3fb49318
authored
Jul 19, 2012
by
Alessandro Rubini
Browse files
Options
Browse Files
Download
Email Patches
Plain Diff
docs: added a more complete example (thanks Wesley)
parent
fc21ca3a
Show whitespace changes
Inline
Side-by-side
Showing
1 changed file
with
42 additions
and
6 deletions
+42
-6
sdb.tex
docs/specification/sdb.tex
+42
-6
No files found.
docs/specification/sdb.tex
View file @
3fb49318
...
...
@@ -852,18 +852,19 @@ The value \textbf{must} point to an SDB array that begins with an \textit{interc
An embedded component info structure, where the type is 0x01 See Table
\ref
{
sdb
_
component
}
.
\end{description}
\section
{
A Simple Real-World Example
}
\section
{
Simple Real-World Examples
}
This section shows the simplest real-world example of an SDB array.
The FPGA binary used as an example is the
\textit
{
boot
}
image to be
This section shows the details of the simplest real-world example of an SDB array,
and an overlook of a more structured device.
\subsection
{
Simple Binary Data
}
The FPGA binary used as the simplest example is the
\textit
{
boot
}
image to be
programmed in the SPEC cards
(
\texttt
{
http://www.ohwr.org/projects/spec
}
); it only includes the
\textit
{
syscon
}
device, which allows generic access to the FMC
mezzanine card.
\subsection
{
Binary Data
}
The following binary dump appears at offset 0x100 of the memory window
that maps to the programmable device:
...
...
@@ -931,6 +932,35 @@ The previous dump shows how the vendor identifiers in this case have
been allocated in the globally-assigned space, while device identifiers
are pseudo-random numbers, in charge of the respective vendor.
\subsection
{
A More Structured Device
}
The following is the output of
\texttt
{
eb-ls
}
, and
\textit
{
Etherbone
}
tool, when run over a complex White Rabbit device. This output
comes from scanning the SDB structures:
\footnotesize
\begin{verbatim}
root@scul007:~# eb-ls dev/pcie
_
wb0
BusPath VendorID Product Base(Hex) Description
1 000000000000ce42:66cfeb52 0 WB4-BlockRAM
2 0000000000000651:eef0b198 100000 WB4-Bridge-GSI
2.1 0000000000000651:35aa6b95 100000 GSI
_
GPIO
_
32
2.2 0000000000000651:8752bf44 140000 GSI
_
ECA
_
UNIT
2.3 0000000000000651:10051981 180000 GSI
_
TM
_
LATCH
3 0000000000000651:eef0b198 200000 WB4-Bridge-GSI
3.1 000000000000ce42:66cfeb52 200000 WB4-BlockRAM
3.2 0000000000000651:eef0b198 220000 WB4-Bridge-GSI
3.2.1 000000000000ce42:ab28633a 220000 WR-Mini-NIC
3.2.2 000000000000ce42:650c2d4f 220100 WR-Endpoint
3.2.3 000000000000ce42:65158dc0 220200 WR-Soft-PLL
3.2.4 000000000000ce42:de0d8ced 220300 WR-PPS-Generator
3.2.5 000000000000ce42:ff07fc47 220400 WR-Periph-Syscon
3.2.6 000000000000ce42:e2d13d04 220500 WR-Periph-UART
3.2.7 000000000000ce42:779c5443 220600 WR-Periph-1Wire
3.2.8 000000000000ce42:779c5443 220700 WR-Periph-1Wire
\end{verbatim}
\normalsize
\subsection
{
Endianness Problems
}
Please note that the host may have some issue reading the binary
...
...
@@ -958,5 +988,11 @@ byte-swap each 32-bit word before using the structure in a
little-endian host. After such swapping, the usual rules for
multi-byte values apply.
\subsection
{
Existing Tools
}
As part of the
\textit
{
Etherbone
}
project, you already find a number
of tools that work with SDB structures (including
\texttt
{
eb-ls
}
that
printed the table of devices shown above). The project is at
\texttt
{
http://www.ohwr.org/projects/etherbone-core
}
.
\end{document}
Write
Preview
Markdown
is supported
0%
Try again
or
attach a new file
Attach a file
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Cancel
Please
register
or
sign in
to comment