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<p>On 14/02/2020 15:45, Joel Sherrill wrote:<br>
</p>
<blockquote type="cite"
cite="mid:CAF9ehCV8c9_pcmpbAqeoWVr362CXe76cjAqskaeTXgZSSWJfgA@mail.gmail.com">
<div dir="ltr" class="gmail_attr">On Fri, Feb 14, 2020 at 7:08 AM
Sebastian Huber <<a
href="mailto:sebastian.huber@embedded-brains.de"
moz-do-not-send="true">sebastian.huber@embedded-brains.de</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On
14/02/2020 13:57, Joel Sherrill wrote:<br>
<br>
> Hi<br>
><br>
> I haven't investigated or checked on other bsps but the
xilinx qemu <br>
> bsp has no output with the hello world in examples. It uses
the devfs. <br>
> Changing it to the default filesystem results in it
working.<br>
><br>
> I am suspicious of something with all the termios and new
console <br>
> changes breaking it.<br>
The devfs works only with legacy IO drivers. The Termios drivers
depend <br>
on IMFS. I would like to remove the devfs in the future. The
IMFS is <br>
highly configurable, there is no need for an additional
in-memory file <br>
system.<br>
</blockquote>
<div><br>
</div>
<div>Do not remove it. Please fix it.</div>
</blockquote>
<p>The IMFS should be improved, so that we can remove the devfs. We
already have a bunch of configuration options to customize it:</p>
<p><a class="moz-txt-link-freetext" href="https://docs.rtems.org/branches/master/c-user/configuring_a_system.html#file-system-configuration-parameters">https://docs.rtems.org/branches/master/c-user/configuring_a_system.html#file-system-configuration-parameters</a><br>
</p>
<blockquote type="cite"
cite="mid:CAF9ehCV8c9_pcmpbAqeoWVr362CXe76cjAqskaeTXgZSSWJfgA@mail.gmail.com">
<div><br>
</div>
<div>This filesystem is needed because some applications want no
filesystem but</div>
<div>you require one for device nodes. Even the IMFS is subject to
mallocs which</div>
<div>are undesired in the applications that this was supporting.</div>
</blockquote>
<p>Termios uses malloc(), so I don't think this filesystem makes
sense for console drivers. I changed the clock driver to use a
simple system initialization handler. Some time ago I refactored
the IMFS mount operation to use statically allocated data:</p>
<p><a class="moz-txt-link-freetext" href="https://git.rtems.org/rtems/commit/?id=a9df9169882c564af6714bbf121c278092d3c51c">https://git.rtems.org/rtems/commit/?id=a9df9169882c564af6714bbf121c278092d3c51c</a></p>
<p>With a bit of work the IMFS_make_generic_node() can be changed to
not allocate memory and instead use memory provided by the caller.
I spend a considerable amount of time to make it possible that
some time in the future we can have applications with purely
statically allocated resources.<br>
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