index: tabs -> spaces
Tabs were causing formatting issues with <code> blocks, so just set the entire file to indent using spaces. Signed-off-by: Sean Cross <sean@xobs.io>
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<head>
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<meta charset="utf-8">
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<meta charset="utf-8">
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<title>Paying It Forward: Documenting your Hardware</title>
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<title>Paying It Forward: Documenting your Hardware</title>
|
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|
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<meta name="description" content="A framework for easily creating beautiful presentations using HTML">
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<meta name="author" content="Sean "xobs" Cross">
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<meta name="description" content="A framework for easily creating beautiful presentations using HTML">
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<meta name="author" content="Sean "xobs" Cross">
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/*********************************************
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* ZOOM REVERSE TRANSITION (i.e. zoom out)
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</style>
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</head>
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<body>
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||||
|
||||
<!-- Start of main presentation -->
|
||||
<div class="reveal">
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<div class="footer">
|
||||
<a class="url" href="https://p.xobs.io/lca20-pif/">p.xobs.io/lca20-pif</a>
|
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<span class="theme">The Linux of Things</span><span class="hashtag"> | #LCA2020</span><span class="twitter"> |
|
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@linuxconfau</span>
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</div>
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<div class="slides">
|
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<section data-background-image="css/theme/lca2019-title-bg-transparent.svg">
|
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<h1>Paying it Forward: Documenting Your Hardware Project</h1>
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<h4>Approaches to documenting a hardware description language using lxsocdoc</h4>
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<p align="right">
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<small>Sean Cross - <a href="https://xobs.io/">https://xobs.io/</a> - @xobs</small>
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</p>
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</section>
|
||||
<!-- Start of main presentation -->
|
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<div class="reveal">
|
||||
<div class="footer">
|
||||
<a class="url" href="https://p.xobs.io/lca20-pif/">p.xobs.io/lca20-pif</a>
|
||||
<span class="theme">The Linux of Things</span><span class="hashtag"> | #LCA2020</span><span class="twitter"> |
|
||||
@linuxconfau</span>
|
||||
</div>
|
||||
<div class="slides">
|
||||
<section data-background-image="css/theme/lca2019-title-bg-transparent.svg">
|
||||
<h1>Paying it Forward: Documenting Your Hardware Project</h1>
|
||||
<h4>Approaches to documenting a hardware description language using lxsocdoc</h4>
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||||
<p align="right">
|
||||
<small>Sean Cross - <a href="https://xobs.io/">https://xobs.io/</a> - @xobs</small>
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</p>
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</section>
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<section>
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||||
<h2>Introduction</h2>
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<aside class="notes">
|
||||
This is the Open ISA miniconf, which today tends to mean FPGAs. This means that
|
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hardware and software are both extensible, and developers will be able to extend
|
||||
the hardware in addition to making modifications to your software package.
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||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Introduction</h2>
|
||||
<aside class="notes">
|
||||
This is the Open ISA miniconf, which today tends to mean FPGAs. This means that
|
||||
hardware and software are both extensible, and developers will be able to extend
|
||||
the hardware in addition to making modifications to your software package.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>About Me</h2>
|
||||
<aside class="notes">
|
||||
My name is Sean Cross, also known as "xobs". I will be speaking later this week
|
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on the Betrusted project, but many know me as the main developer behind the Fomu
|
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project. Fomu is an FPGA that fits in your USB port. One of my goals with the
|
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Fomu project was to allow people to treat it as just a RISC-V CPU in their USB
|
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port, which means now we need to make documentation. This talk covers some of
|
||||
the problems I ran into while working on this project, and the solutions I came
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up with.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>About Me</h2>
|
||||
<aside class="notes">
|
||||
My name is Sean Cross, also known as "xobs". I will be speaking later this week
|
||||
on the Betrusted project, but many know me as the main developer behind the Fomu
|
||||
project. Fomu is an FPGA that fits in your USB port. One of my goals with the
|
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Fomu project was to allow people to treat it as just a RISC-V CPU in their USB
|
||||
port, which means now we need to make documentation. This talk covers some of
|
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the problems I ran into while working on this project, and the solutions I came
|
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up with.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Undocumented Hardware = Bad</h2>
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<h4>(But so easy to do!)</h4>
|
||||
<aside class="notes">
|
||||
Undocumented hardware is bad. There are all sorts of quirks, and even if you have
|
||||
the source code, it can be very difficult to read. I'm the primary developer for
|
||||
the Fomu project, and this talk will cover some of the issues I've run into with
|
||||
respect to documentation. It is most directly related to the LiteX and Migen
|
||||
projects, but the concepts will carry over into any other Hardware Description
|
||||
Language you may use.
|
||||
<section>
|
||||
<h2>Undocumented Hardware = Bad</h2>
|
||||
<h4>(But so easy to do!)</h4>
|
||||
<aside class="notes">
|
||||
Undocumented hardware is bad. There are all sorts of quirks, and even if you have
|
||||
the source code, it can be very difficult to read. I'm the primary developer for
|
||||
the Fomu project, and this talk will cover some of the issues I've run into with
|
||||
respect to documentation. It is most directly related to the LiteX and Migen
|
||||
projects, but the concepts will carry over into any other Hardware Description
|
||||
Language you may use.
|
||||
|
||||
The goal of this talk is to show how it's easy to document hardware with
|
||||
the right framework, and how it's easier to have a project that's documented
|
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than one that isn't.
|
||||
</aside>
|
||||
</section>
|
||||
The goal of this talk is to show how it's easy to document hardware with
|
||||
the right framework, and how it's easier to have a project that's documented
|
||||
than one that isn't.
|
||||
</aside>
|
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</section>
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<section>
|
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<h2>Talk Outline</h2>
|
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<ol>
|
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<li>How to write HDL Code</li>
|
||||
<li>Rationale behind <tt>lxsocdoc</tt></li>
|
||||
<li>Examples of <tt>lxsocdoc</tt></li>
|
||||
<li>Benefits of this approach</li>
|
||||
</ol>
|
||||
<aside class="notes">
|
||||
I'll briefly cover various methods of writing HDL code, then cover the rationale
|
||||
behind the approach we take with lxsocdoc, then give an example of how to use
|
||||
lxsocdoc and how you might apply it to your language. Finally, I'll cover the
|
||||
implications of having documented hardware and how this will help you pay it forward.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Talk Outline</h2>
|
||||
<ol>
|
||||
<li>How to write HDL Code</li>
|
||||
<li>Rationale behind <tt>lxsocdoc</tt></li>
|
||||
<li>Examples of <tt>lxsocdoc</tt></li>
|
||||
<li>Benefits of this approach</li>
|
||||
</ol>
|
||||
<aside class="notes">
|
||||
I'll briefly cover various methods of writing HDL code, then cover the rationale
|
||||
behind the approach we take with lxsocdoc, then give an example of how to use
|
||||
lxsocdoc and how you might apply it to your language. Finally, I'll cover the
|
||||
implications of having documented hardware and how this will help you pay it forward.
|
||||
</aside>
|
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</section>
|
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|
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<section>
|
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<h2>Motivation</h2>
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<pre><code class="hljs cpp">// Hardware definitions of the SoC. Also is the main repo of
|
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<section>
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<h2>Motivation</h2>
|
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<pre><code class="hljs cpp">// Hardware definitions of the SoC. Also is the main repo of
|
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// documentation for the programmer-centric view
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// of the hardware.
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/* Start of memory range for the UART peripheral */
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@ -165,46 +165,55 @@
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The debug UART is always configured as 8N1. */
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#define UART_DATA_REG 0x00</code></pre>
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<p><tt>mach_defines.h</tt>, Hackaday 2019 Con Badge</p>
|
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<aside class="notes">
|
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Verilog and VHDL are kind of the C or assembly of the FPGA world. They're universal,
|
||||
but somewhat unwieldy to use. You need to manually set up your address decoders,
|
||||
and documentation is very free-form. Common approaches today involve comments in
|
||||
the HDL and/or C header files. This works, but we can do better. We just need to
|
||||
describe the hardware better.
|
||||
</aside>
|
||||
</section>
|
||||
<aside class="notes">
|
||||
Verilog and VHDL are kind of the C or assembly of the FPGA world. They're universal,
|
||||
but somewhat unwieldy to use. You need to manually set up your address decoders,
|
||||
and documentation is very free-form. Common approaches today involve comments in
|
||||
the HDL and/or C header files. This works, but we can do better. We just need to
|
||||
describe the hardware better.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>About LiteX and lxsocdoc</h2>
|
||||
<aside class="notes">
|
||||
Fomu uses LiteX, which is related to Migen. This is a hardware description language
|
||||
written in Python. You write Python code and run the program, and it generates
|
||||
a design file -- either Verilog code, or a Yosys netlist. There are many other
|
||||
alternatives such as SpinalHDL or Chisel. By writing in Python as opposed to
|
||||
direct Verilog, we get a lot of nice primitives. The examples from this talk
|
||||
are taken from lxsocdoc and LiteX, but most higher-level hardware description
|
||||
languages can take similar approaches to documentation.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>About LiteX</h2>
|
||||
<ol>
|
||||
<li>Hardware Description Language embedded in Python</li>
|
||||
<ol>
|
||||
<li>Doesn't run Python in hardware!</li>
|
||||
</ol>
|
||||
<li>Emits Verilog (or Yosys netlists)</li>
|
||||
<li>Makes it easy to create a SoC</li>
|
||||
<li>Powers the LCA2020 video production setup</li>
|
||||
</ol>
|
||||
<aside class="notes">
|
||||
Fomu uses LiteX, which is related to Migen. This is a hardware description language
|
||||
written in Python. You write Python code and run the program, and it generates
|
||||
a design file -- either Verilog code, or a Yosys netlist. There are many other
|
||||
alternatives such as SpinalHDL or Chisel. By writing in Python as opposed to
|
||||
direct Verilog, we get a lot of nice primitives. The examples from this talk
|
||||
are taken from lxsocdoc and LiteX, but most higher-level hardware description
|
||||
languages can take similar approaches to documentation.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<section>
|
||||
<h2>LiteX Primitives</h2>
|
||||
<pre><code class="python" data-trim>class GPIOOut(Module, AutoCSR):
|
||||
def __init__(self, signal):
|
||||
self._out = CSRStorage(len(signal))
|
||||
self.comb += signal.eq(self._out.storage)</code></pre>
|
||||
<aside class="notes">
|
||||
In LiteX, two of the primitives used to expose hardware registers to the CPU softcore
|
||||
are CSRStorage and CSRStatus. Instead of manually wiring up a crossbar and decoding
|
||||
the addresses ourselves, we just need to write `self.regname = CSRStatus(8)`,
|
||||
and the build system will wire up 8 bits of read-only memory to the target CPU.
|
||||
Similarly, `self.othername = CSRStorage(8)` will give 8-bits of write-only memory.
|
||||
</aside>
|
||||
</section>
|
||||
<aside class="notes">
|
||||
In LiteX, two of the primitives used to expose hardware registers to the CPU softcore
|
||||
are CSRStorage and CSRStatus. Instead of manually wiring up a crossbar and decoding
|
||||
the addresses ourselves, we just need to write `self.regname = CSRStatus(8)`,
|
||||
and the build system will wire up 8 bits of read-only memory to the target CPU.
|
||||
Similarly, `self.othername = CSRStorage(8)` will give 8-bits of write-only memory.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h4>SPI Bitbang Module</h4>
|
||||
<pre><code class="python" data-trim>self.bitbang = CSRStorage(4)
|
||||
<section>
|
||||
<h4>Case Study: SPI Bitbang Module</h4>
|
||||
<pre><code class="python" data-trim>self.bitbang = CSRStorage(4)
|
||||
If(self.bitbang.storage[3],
|
||||
dq.oe.eq(0)
|
||||
).Else(
|
||||
@ -217,33 +226,47 @@ If(self.bitbang.storage[1],
|
||||
dq.o.eq(
|
||||
Cat(self.bitbang.storage[0], Replicate(1, spi_width-1))
|
||||
)</code></pre>
|
||||
<aside class="notes">
|
||||
This works well, but exposes a new problem: Documentation. As an example, I was
|
||||
working with the SPI Flash block in litex, and wanted to know how the bitbang
|
||||
driver worked. There wasn't any documentation except the source, which looked
|
||||
like this.
|
||||
<aside class="notes">
|
||||
This works well, but exposes a new problem: Documentation. As an example, I was
|
||||
working with the SPI Flash block in litex, and wanted to know how the bitbang
|
||||
driver worked. There wasn't any documentation except the source, which looked
|
||||
like this.
|
||||
|
||||
You can kind of understand it, but it does take a lot of mental power to
|
||||
work through it. I started by creating aliases for the various elements
|
||||
in the storage array, but then I thought: There has to be a better way!
|
||||
</aside>
|
||||
</section>
|
||||
You can kind of understand it, but it does take a lot of mental power to
|
||||
work through it. I started by creating aliases for the various elements
|
||||
in the storage array, but then I thought: There has to be a better way!
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Aside: Python Docstrings</h2>
|
||||
<aside class="notes">
|
||||
As an aside, Python has something called Pydoc and Docstrings. These are
|
||||
comments that go at the top of functions and classes that let you describe
|
||||
what a Python object is and how to use it. This is almost what we want,
|
||||
except once the final SoC is generated we don't really care so much about
|
||||
things like constructor arguments or method properties. Documentation for
|
||||
the end user is different from documentation for the module developer.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Aside: Python Docstrings</h2>
|
||||
<pre><code class="python" data-trim>def _format_cmd(cmd, spi_width):
|
||||
"""
|
||||
`cmd` is the read instruction. Since everything is
|
||||
transmitted on all dq lines (cmd, adr and data), extend/
|
||||
interleave cmd to full pads.dq width even if dq1-dq3 are
|
||||
don't care during the command phase: For example, for
|
||||
N25Q128, 0xeb is the quad i/o fast read, and extended
|
||||
to 4 bits (dq1,dq2,dq3 high) is: 0xfffefeff
|
||||
"""
|
||||
c = 2**(8*spi_width)-1
|
||||
for b in range(8):
|
||||
if not (cmd>>b)%2:
|
||||
c &= ~(1<<(b*spi_width))
|
||||
return c</code></pre>
|
||||
<aside class="notes">
|
||||
As an aside, Python has something called Pydoc and Docstrings. These are
|
||||
comments that go at the top of functions and classes that let you describe
|
||||
what a Python object is and how to use it. This is almost what we want,
|
||||
except once the final SoC is generated we don't really care so much about
|
||||
things like constructor arguments or method properties. Documentation for
|
||||
the end user is different from documentation for the module developer.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h4>New Register Definition</h4>
|
||||
<pre><code class="python" data-trim>self.bitbang = CSRStorage(4, fields=[
|
||||
<section>
|
||||
<h2>New Register Definition</h2>
|
||||
<pre><code class="python" data-trim>self.bitbang = CSRStorage(4, fields=[
|
||||
CSRField("mosi", description="Output value for MOSI..."
|
||||
CSRField("clk", description="Output value for SPI CLK..."
|
||||
CSRField("cs_n", description="Output value for SPI C..."
|
||||
@ -252,22 +275,22 @@ dq.o.eq(
|
||||
("1", "IN", "SPI pins are all input"),
|
||||
])
|
||||
], description="""Bitbang controls for SPI output. Only
|
||||
standard 1x SPI is supported, and as a result all
|
||||
four wires are ganged together. This means that it
|
||||
is only possible to perform half-duplex operations,
|
||||
using this SPI core.""")</code></pre>
|
||||
<aside class="notes">
|
||||
This is when I hit upon the idea of `lxsocdoc`. The basic idea is that
|
||||
Python is really good at introspecting Python, so let's add a little bit
|
||||
more information to the CSR objects to make our life easier. And so, after
|
||||
working with the LiteX creator Florent, we refactored the bitbang
|
||||
definition to this.
|
||||
</aside>
|
||||
</section>
|
||||
standard 1x SPI is supported, and as a result all
|
||||
four wires are ganged together. This means that it
|
||||
is only possible to perform half-duplex operations,
|
||||
using this SPI core.""")</code></pre>
|
||||
<aside class="notes">
|
||||
This is when I hit upon the idea of `lxsocdoc`. The basic idea is that
|
||||
Python is really good at introspecting Python, so let's add a little bit
|
||||
more information to the CSR objects to make our life easier. And so, after
|
||||
working with the LiteX creator Florent, we refactored the bitbang
|
||||
definition to this.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h4>Refactored SPI Bitbang</h4>
|
||||
<pre><code class="python" data-trim>If(self.bitbang.fields.dir,
|
||||
<section>
|
||||
<h2>Refactored SPI Bitbang</h2>
|
||||
<pre><code class="python" data-trim>If(self.bitbang.fields.dir,
|
||||
dq.oe.eq(0)
|
||||
).Else(
|
||||
dq.oe.eq(1)
|
||||
@ -279,198 +302,198 @@ If(self.bitbang.fields.clk,
|
||||
dq.o.eq(
|
||||
Cat(self.bitbang.fields.mosi, Replicate(1, spi_width-1))
|
||||
)</code></pre>
|
||||
<aside class="notes">
|
||||
Now the actual bitbang logic looks like this.
|
||||
<aside class="notes">
|
||||
Now the actual bitbang logic looks like this.
|
||||
|
||||
This is a little bit easier to understand -- no longer are we looking at indices
|
||||
in an array to determine what field does what. Instead we get actual named fields.
|
||||
But because Python can introspect Python very easily, this is just the beginning.
|
||||
</aside>
|
||||
</section>
|
||||
This is a little bit easier to understand -- no longer are we looking at indices
|
||||
in an array to determine what field does what. Instead we get actual named fields.
|
||||
But because Python can introspect Python very easily, this is just the beginning.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<section>
|
||||
<h2>Generating a Manual</h2>
|
||||
<img data-src="img/lxspi_bitbang.png">
|
||||
<aside class="notes">
|
||||
After the design is elaborated and the output file is generated, we can iterate
|
||||
through the resulting tree and pick out any CSR objects and using any additional
|
||||
information. We can actually generate a full reference manual, just like one you
|
||||
would receive from a SoC Vendor.
|
||||
<aside class="notes">
|
||||
After the design is elaborated and the output file is generated, we can iterate
|
||||
through the resulting tree and pick out any CSR objects and using any additional
|
||||
information. We can actually generate a full reference manual, just like one you
|
||||
would receive from a SoC Vendor.
|
||||
|
||||
For example, this is what the start of the Fomu SPI Flash documentation looks like:
|
||||
[Register Listing for LXSPI]
|
||||
For example, this is what the start of the Fomu SPI Flash documentation looks like:
|
||||
[Register Listing for LXSPI]
|
||||
|
||||
This is already pretty useful. You can hand this file to someone and show them
|
||||
how your design works. But the title of this talk is called "Paying it Forward",
|
||||
and I can tell you from experience that having such a reference manual for yourself
|
||||
while developing software for your own hardware is still invaluable. Hardware
|
||||
designs are complex things, and not having to decode bitfield offsets in your
|
||||
head or constantly referring to various sections of code to see how it's implemented
|
||||
saves valuable time.
|
||||
</aside>
|
||||
</section>
|
||||
This is already pretty useful. You can hand this file to someone and show them
|
||||
how your design works. But the title of this talk is called "Paying it Forward",
|
||||
and I can tell you from experience that having such a reference manual for yourself
|
||||
while developing software for your own hardware is still invaluable. Hardware
|
||||
designs are complex things, and not having to decode bitfield offsets in your
|
||||
head or constantly referring to various sections of code to see how it's implemented
|
||||
saves valuable time.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Undocumented Fields</h2>
|
||||
<aside class="notes">
|
||||
It turns out that there is enough information that we can extract that
|
||||
even undocumented fields are somewhat useful.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Undocumented Fields</h2>
|
||||
<aside class="notes">
|
||||
It turns out that there is enough information that we can extract that
|
||||
even undocumented fields are somewhat useful.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Interrupts</h2>
|
||||
<section>
|
||||
<h2>Interrupts</h2>
|
||||
<img data-src="img/interrupts.png">
|
||||
<aside class="notes">
|
||||
We can even extract interrupt information, including which bits inside an
|
||||
interrupt register map to which event, and which interrupt number is assigned
|
||||
to a given module.
|
||||
</aside>
|
||||
</section>
|
||||
<aside class="notes">
|
||||
We can even extract interrupt information, including which bits inside an
|
||||
interrupt register map to which event, and which interrupt number is assigned
|
||||
to a given module.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>More Documentation: ModuleDoc</h2>
|
||||
<section>
|
||||
<h2>More Documentation: ModuleDoc</h2>
|
||||
<img data-src="img/timer0-doc.png">
|
||||
<aside class="notes">
|
||||
So now we have register documentation. Can we do better? Of course we can.
|
||||
SoC reference manuals are more than just register definitions. They also include
|
||||
background information on protocols, as well as more elaboration on how the block
|
||||
works. We can take a cue from CSRs themselves, and add module documentation
|
||||
in a similar fashion.
|
||||
</aside>
|
||||
</section>
|
||||
<aside class="notes">
|
||||
So now we have register documentation. Can we do better? Of course we can.
|
||||
SoC reference manuals are more than just register definitions. They also include
|
||||
background information on protocols, as well as more elaboration on how the block
|
||||
works. We can take a cue from CSRs themselves, and add module documentation
|
||||
in a similar fashion.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Protocol Documentation</h2>
|
||||
<section>
|
||||
<h2>Protocol Documentation</h2>
|
||||
<img data-src="img/usb-wishbone.png">
|
||||
<aside class="notes">
|
||||
We can add additional documentation such as protocol waveforms. Here
|
||||
we use WaveDrom to define the protocol of Wishbone-over-SPI. There
|
||||
are multiple formats of the protocol depending on which version is
|
||||
instantiated.
|
||||
</aside>
|
||||
</section>
|
||||
<aside class="notes">
|
||||
We can add additional documentation such as protocol waveforms. Here
|
||||
we use WaveDrom to define the protocol of Wishbone-over-SPI. There
|
||||
are multiple formats of the protocol depending on which version is
|
||||
instantiated.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>SVD: Documentation for Machines</h2>
|
||||
<aside class="notes">
|
||||
Having documentation for humans is great, but we can go one step further and
|
||||
make documentation for computers. SVD is an XML format defined by ARM that
|
||||
defines various aspects about a chip, including memory layout, interrupt map,
|
||||
and register sets. SVD includes information such as default values and field
|
||||
bits, all information we have thanks to the introspectability of Python.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>SVD: Documentation for Machines</h2>
|
||||
<aside class="notes">
|
||||
Having documentation for humans is great, but we can go one step further and
|
||||
make documentation for computers. SVD is an XML format defined by ARM that
|
||||
defines various aspects about a chip, including memory layout, interrupt map,
|
||||
and register sets. SVD includes information such as default values and field
|
||||
bits, all information we have thanks to the introspectability of Python.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>SVD2Rust: Generating Safe Accessors</h2>
|
||||
<aside class="notes">
|
||||
In addition to generating a reference manual for humans, we can generate an SVD
|
||||
file that's usable in a wide variety of areas. For example, we can turn an SVD
|
||||
file into a Rust Peripheral Access Crate (PAC) using `SVD2Rust`, giving us an
|
||||
easy way to safely access all peripherals on a device.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>SVD2Rust: Generating Safe Accessors</h2>
|
||||
<aside class="notes">
|
||||
In addition to generating a reference manual for humans, we can generate an SVD
|
||||
file that's usable in a wide variety of areas. For example, we can turn an SVD
|
||||
file into a Rust Peripheral Access Crate (PAC) using `SVD2Rust`, giving us an
|
||||
easy way to safely access all peripherals on a device.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Renode: Fancy Register Logging</h2>
|
||||
<aside class="notes">
|
||||
We can also import this SVD file into an emulator such as Renode, which will
|
||||
print out fields and flags that get accessed, giving us greater visibility into
|
||||
what a program is doing.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Renode: Fancy Register Logging</h2>
|
||||
<aside class="notes">
|
||||
We can also import this SVD file into an emulator such as Renode, which will
|
||||
print out fields and flags that get accessed, giving us greater visibility into
|
||||
what a program is doing.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Benefits of Higher Level Languages</h2>
|
||||
<aside class="notes">
|
||||
By using a higher level language, we are able to describe the hardware
|
||||
in greater detail than if we used Verilog or VHDL. We can add additional
|
||||
fields to our register definition fields to provide nice, human-readable
|
||||
documentation. This also allows us to generate machine-readable formats
|
||||
such as SVD, which opens up a whole world of software.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Benefits of Higher Level Languages</h2>
|
||||
<aside class="notes">
|
||||
By using a higher level language, we are able to describe the hardware
|
||||
in greater detail than if we used Verilog or VHDL. We can add additional
|
||||
fields to our register definition fields to provide nice, human-readable
|
||||
documentation. This also allows us to generate machine-readable formats
|
||||
such as SVD, which opens up a whole world of software.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Documentation helps you</h2>
|
||||
<h2>Documentation helps others</h2>
|
||||
<aside class="notes">
|
||||
Documenting your hardware is important because it is necessary for you to
|
||||
write software that interfaces with it today, and it helps you work with
|
||||
others when it comes time to share your design with the world. By
|
||||
properly documenting various fields within your module, you make it easier
|
||||
on yourself to interact with today, and you make it easier to let others
|
||||
get up to speed in the future. By documenting your hardware, you're helping
|
||||
to pay it forward.
|
||||
</aside>
|
||||
</section>
|
||||
<section>
|
||||
<h2>Documentation helps you</h2>
|
||||
<h2>Documentation helps others</h2>
|
||||
<aside class="notes">
|
||||
Documenting your hardware is important because it is necessary for you to
|
||||
write software that interfaces with it today, and it helps you work with
|
||||
others when it comes time to share your design with the world. By
|
||||
properly documenting various fields within your module, you make it easier
|
||||
on yourself to interact with today, and you make it easier to let others
|
||||
get up to speed in the future. By documenting your hardware, you're helping
|
||||
to pay it forward.
|
||||
</aside>
|
||||
</section>
|
||||
|
||||
<section>
|
||||
<h2>Thank you</h2>
|
||||
<h3>Questions</h3>
|
||||
</section>
|
||||
</div>
|
||||
</div> <!-- class="reveal" -->
|
||||
<!-- End of main presentation -->
|
||||
<section>
|
||||
<h2>Thank you</h2>
|
||||
<h3>Questions</h3>
|
||||
</section>
|
||||
</div>
|
||||
</div> <!-- class="reveal" -->
|
||||
<!-- End of main presentation -->
|
||||
|
||||
<!-- Start of configuration section -->
|
||||
<script src="lib/js/head.min.js"></script>
|
||||
<script src="js/reveal.js"></script>
|
||||
<!-- Start of configuration section -->
|
||||
<script src="lib/js/head.min.js"></script>
|
||||
<script src="js/reveal.js"></script>
|
||||
|
||||
<script>
|
||||
var presenter = !!Reveal.getQueryHash().s;
|
||||
<script>
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||||
var presenter = !!Reveal.getQueryHash().s;
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|
||||
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||||
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||||
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||||
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||||
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|
||||
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||||
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||||
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|
||||
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</html>
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Reference in New Issue
Block a user