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<b>GXemul documentation:</b></font> |
<b>Gavare's eXperimental Emulator:</b></font><br> |
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<font color="#000000" size="6"><b>Introduction</b> |
<font color="#000000" size="6"><b>Introduction</b> |
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$Id: intro.html,v 1.46 2005/06/04 12:02:17 debug Exp $ |
$Id: intro.html,v 1.106 2007/02/18 09:19:47 debug Exp $ |
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Copyright (C) 2003-2005 Anders Gavare. All rights reserved. |
Copyright (C) 2003-2007 Anders Gavare. All rights reserved. |
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Redistribution and use in source and binary forms, with or without |
Redistribution and use in source and binary forms, with or without |
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modification, are permitted provided that the following conditions are met: |
modification, are permitted provided that the following conditions are met: |
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<h2>Introduction</h2> |
<h2>Introduction</h2> |
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<p> |
<p> |
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<table border="0" width="99%"><tr><td valign="top" align="left"> |
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<ul> |
<ul> |
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<li><a href="#overview">Overview</a> |
<li><a href="#overview">Overview</a> |
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<li><a href="#free">Is GXemul Free software?</a> |
<li><a href="#free">Is GXemul Free software?</a> |
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<li><a href="#build">How to compile/build the emulator</a> |
<li><a href="#build">How to compile/build the emulator</a> |
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<li><a href="#run">How to run the emulator</a> |
<li><a href="#run">How to run the emulator</a> |
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<li><a href="#cpus">Which CPU types does GXemul emulate?</a> |
<li><a href="#cpus">Which processor architectures does GXemul emulate?</a> |
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<li><a href="#hosts">Which host architectures are supported?</a> |
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<li><a href="#translation">What kind of translation does GXemul use?</a> |
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<li><a href="#accuracy">Emulation accuracy</a> |
<li><a href="#accuracy">Emulation accuracy</a> |
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<li><a href="#emulmodes">Which machines does GXemul emulate?</a> |
<li><a href="#emulmodes">Which machines does GXemul emulate?</a> |
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<li><a href="#guestos">Which guest OSes are possible to run?</a> |
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</ul> |
</ul> |
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</td><td valign="center" align="center"> |
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<a href="20050317-example.png"><img src="20050317-example_small.png"></a> |
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<p>NetBSD/pmax 1.6.2 with X11<br>running in GXemul</td></tr></table> |
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<a name="overview"></a> |
<a name="overview"></a> |
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<h3>Overview:</h3> |
<h3>Overview:</h3> |
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GXemul is a machine emulator, which can be used to experiment with |
GXemul is an experimental instruction-level machine emulator. Several |
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binary code for (among others) MIPS-based machines. Several emulation |
emulation modes are available. In some modes, processors and surrounding |
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modes are available. For some emulation modes, processors and surrounding |
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hardware components are emulated well enough to let unmodified operating |
hardware components are emulated well enough to let unmodified operating |
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systems run as if they were running on a real machine. |
systems (e.g. NetBSD) run as if they were running on a real machine. |
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<p> |
<p>Devices and processors are not simulated with 100% accuracy. They are |
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Devices and CPUs are not simulated with 100% accuracy. They are only |
only ``faked'' well enough to allow guest operating systems to run without |
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"faked" well enough to make operating systems (eg NetBSD) run without |
complaining too much. Still, the emulator could be of interest for |
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complaining too much. Still, the emulator could be of interest for |
academic research and experiments, such as when learning how to write |
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academic research and experiments, such as when learning how to write |
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operating system code. |
operating system code. |
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<p> |
<p>The emulator is written in C, does not depend on third-party libraries, |
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The emulator is written in C, does not depend on external libraries (except |
and should compile and run on most 64-bit and 32-bit Unix-like systems. |
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X11, but that is optional), and should compile and run on most Unix-like |
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systems. If it doesn't, then that is a bug. |
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(You do not need any MIPS compiler toolchain to build or use GXemul. |
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If you need to compile MIPS binaries from sources, then of course you need |
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such a toolchain, but that is completely separate from GXemul.) |
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<p> |
<p>The emulator contains code which tries to emulate the workings of CPUs |
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The emulator contains code which tries to emulate the workings of CPUs and |
and surrounding hardware found in real machines, but it does not contain |
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surrounding hardware found in real machines, but it does not contain any |
any ROM code. You will need some form of program (in binary form) to run |
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ROM code. You will need some form of program (in binary form) to run in |
in the emulator. For many emulation modes, PROM calls are handled by the |
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the emulator. For many emulation modes, PROM calls are handled by the |
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emulator itself, so you do not need to use any ROM image at all. |
emulator itself, so you do not need to use any ROM image at all. |
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<p> |
<p>You can use pre-compiled kernels (for example NetBSD kernels, or |
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You can use pre-compiled kernels (for example NetBSD kernels, or Linux), |
Linux), or other programs that are in binary format, and in some cases |
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or other programs that are in binary format, and in some cases even actual |
even actual ROM images. A couple of different file formats are supported |
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ROM images. A couple of different file formats are supported (ELF, a.out, |
(ELF, a.out, ECOFF, SREC, and raw binaries). |
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ECOFF, SREC, and raw binaries). |
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<p> |
<p>If you do not have a kernel as a separate file, but you have a bootable |
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If you do not have a kernel as a separate file, but you have a bootable |
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disk image, then it is sometimes possible to boot directly from that |
disk image, then it is sometimes possible to boot directly from that |
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image. (This works for example with DECstation emulation, or when booting |
image. (This works for example with DECstation emulation, Dreamcast |
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from ISO9660 CDROM images.) |
emulation, or when booting from generic ISO9660 CDROM images if the |
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kernel is included in the image as a plain file.) |
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<p>Thanks to (in no specific order) Joachim Buss, Olivier Houchard, Juli |
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Mallett, Juan Romero Pardines, Alec Voropay, Göran Weinholt, Alexander |
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Yurchenko, and everyone else who has provided me with feedback. |
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four freedoms associated with Free software, <a |
four freedoms associated with Free software, <a |
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href="http://www.gnu.org/philosophy/free-sw.html">http://www.gnu.org/philosophy/free-sw.html</a>.) |
href="http://www.gnu.org/philosophy/free-sw.html">http://www.gnu.org/philosophy/free-sw.html</a>.) |
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<p> |
<p>The code I have written is released under a 3-clause BSD-style license |
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The code I have written is released under a 3-clause BSD-style license |
(or "revised BSD-style" if one wants to use <a |
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(or "revised BSD-style" if one wants to use |
href="http://www.gnu.org/philosophy/bsd.html">GNU jargon</a>). Apart from |
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<a href="http://www.gnu.org/philosophy/bsd.html">GNU jargon</a>). |
the code I have written, some files are copied from other sources such as |
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Apart from the code I have written, some files are copied from other sources |
NetBSD, for example header files containing symbolic names of bitfields in |
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such as NetBSD, for example header files containing symbolic names of |
device registers. They are also covered by similar licenses, but with some |
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bitfields in device registers. They are also covered by similar licenses, |
additional clauses. The main point, however, is that the licenses require |
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but with some additional clauses. If you plan to redistribute GXemul |
that the original Copyright and license terms are included when you make a |
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(for example as a binary package), or reuse code from GXemul, |
copy or modification. |
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then you should check those files for their license terms. |
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<p>If you plan to redistribute GXemul <i>without</i> supplying the source |
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<p> |
code, then you need to comply with each individual source file some other |
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(The licenses usually require that the original Copyright and license |
way, for example by writing additional documentation containing copyright |
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terms are included when you make a copy or modification. The "easiest way |
notes. I have not done this, since I do not plan on making distributions |
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out" if you plan to redistribute code from GXemul is to simply supply |
without source code. You need to check all individual files for details. |
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the source code. You should however check individual files for details.) |
The "easiest way out" if you plan to redistribute code from GXemul is, of |
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course, to let it remain open source and simply supply the source code. |
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<p>In case you want to reuse parts of GXemul, but you need to do that |
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under a different license (e.g. the GPL), then contact me and I might |
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re-license/dual-license files on a case-by-case basis. |
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$ <b>make</b> |
$ <b>make</b> |
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</pre> |
</pre> |
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<p> |
<p>This should work on most Unix-like systems. GXemul does not require any |
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This should work on most Unix-like systems. If it doesn't, then |
specific libraries to build, however, if you build on a system which does |
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mail me a bug report. |
not have X11 libraries installed, some functionality will be lost. |
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<p> |
<p>The emulator's performance is highly dependent on both runtime settings |
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(Note for Windows users: there is a possibility that some releases |
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and/or snapshots will also work with Cygwin, but I can't promise that.) |
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<p> |
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The emulator's performance is highly dependent on both runtime settings |
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and on compiler settings, so you might want to experiment with different |
and on compiler settings, so you might want to experiment with different |
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CC and CFLAGS environment variable values. For example, on a modern PC, |
CC and CFLAGS environment variable values. For example, on an AMD Athlon |
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you could try the following: |
host, you might want to try setting <tt>CFLAGS</tt> to <tt>-march=athlon</tt> |
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<p> |
before running <tt>configure</tt>. |
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$ <b>CFLAGS="-mcpu=pentium4 -O3" ./configure</b> |
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$ <b>make</b> |
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</pre> |
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<p> |
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Run <b><tt>./configure --help</tt></b> to get a list of configure options. (The |
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possible options differ between different releases and snapshots.) |
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<p><br> |
<p><br> |
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<a name="cpus"></a> |
<a name="cpus"></a> |
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<h3>Which CPU types does GXemul emulate?</h3> |
<h3>Which processor architectures does GXemul emulate?</h3> |
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The architectures that are emulated well enough to let at least one |
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guest operating system run (per architecture) are ARM, MIPS, PowerPC, |
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and SuperH. |
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<p>Please read the page about <a href="guestoses.html">guest operating |
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systems</a> for more information about the machines and operating systems |
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that can be considered "working" in the emulator. |
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<p><br> |
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<a name="hosts"></a> |
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<h3>Which host architectures are supported?</h3> |
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GXemul should compile and run on any modern host architecture (64-bit or |
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32-bit word-length). |
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<p>Note: The dynamic translation engine does <i>not</i> require backends |
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for native code generation to be written for each individual host |
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architecture; the "intermediate representation" that the dyntrans system |
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uses can be executed on any host architecture. |
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<h4>MIPS:</h4> |
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Emulation of R4000, which is a 64-bit CPU, was my initial goal. |
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R2000/R3000-like CPUs (32-bit), R1x000, and generic MIPS32/MIPS64-style |
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CPUs are also emulated, and are hopefully almost as stable as the R4000 |
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emulation. |
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<p> |
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I have written an experimental dynamic binary translation subsystem. |
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This gives higher total performance than interpreting one instruction at a |
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time and executing it. (If you wish to enable bintrans, add <b>-b</b> to |
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the command line, but keep in mind that it is still experimental.) |
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<h4>URISC:</h4> |
<p><br> |
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<a name="translation"></a> |
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<h3>What kind of translation does GXemul use?</h3> |
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<b>Static vs. dynamic:</b> |
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I have implemented an <a href="http://en.wikipedia.org/wiki/URISC">URISC</a> |
<p>In order to support guest operating systems, which can overwrite old |
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emulation mode, just for fun. The only instruction available in an URISC |
code pages in memory with new code, it is necessary to translate code |
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machine is "reverse subtract and skip on borrow". (It is probably not |
dynamically. It is not possible to do a "one-pass" (static) translation. |
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worth trying to do bintrans with URISC, because any reasonable URISC |
Self-modifying code and Just-in-Time compilers running inside |
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program relies on self-modifying code, which is bad for bintrans |
the emulator are other things that would not work with a static |
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performance.) |
translator. GXemul is a dynamic translator. However, it does not |
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necessarily translate into native code, like many other emulators. |
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<p><b>"Runnable" Intermediate Representation:</b> |
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<p>Dynamic translators usually translate from the emulated architecture |
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(e.g. MIPS) into a kind of <i>intermediate representation</i> (IR), and then |
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to native code (e.g. AMD64 or x86 code). Since one of my main goals for |
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GXemul is to keep everything as portable as possible, I have tried to make |
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sure that the IR is something which can be executed regardless of whether |
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the final step (translation from IR to native code) has been implemented |
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or not. |
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<p>The IR in GXemul consists of arrays of pointers to functions, and a few |
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arguments which are passed along to those functions. The functions are |
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implemented in either manually hand-coded C, or automatically generated C. |
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In any case, this is all statically linked into the GXemul binary at link |
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time. |
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<p>Here is a simplified diagram of how these arrays work. |
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<p><center><img src="simplified_dyntrans.png"></center> |
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<p>There is one instruction call slot for every possible program counter |
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location. In the MIPS case, instruction words are 32 bits in length, |
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and pages are (usually) 4 KB large, resulting in 1024 instruction call |
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slots. After the last of these instruction calls, there is an additional |
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call to a special "end of page" function (which doesn't count as an executed |
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instruction). This function switches to the first instruction |
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on the next virtual page (which might cause exceptions, etc). |
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<p>The complexity of individual instructions vary. A simple example of |
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what an instruction can look like is the MIPS <tt>addiu</tt> instruction: |
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<pre> |
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X(addiu) |
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{ |
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reg(ic->arg[1]) = (int32_t) |
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((int32_t)reg(ic->arg[0]) + (int32_t)ic->arg[2]); |
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} |
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</pre> |
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<h4>POWER/PowerPC</h4> |
<p>It stores the result of a 32-bit addition of the register at arg[0] |
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with the immediate value arg[2] (treating both as signed 32-bit |
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integers) into register arg[1]. If the emulated CPU is a 64-bit CPU, |
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then this will store a correctly sign-extended value into arg[1]. |
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If it is a 32-bit CPU, then only the lowest 32 bits will be stored, |
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and the high part ignored. <tt>X(addiu)</tt> is expanded to |
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<tt>mips_instr_addiu</tt> in the 64-bit case, and <tt>mips32_instr_addiu</tt> |
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in the 32-bit case. Both are compiled into the GXemul executable; no code |
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is created during run-time. |
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<p>Here are examples of what the <tt>addiu</tt> instruction actually |
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looks like when it is compiled, on various host architectures: |
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<p><center><table border="0"> |
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<tr><td><b>GCC 4.0.1 on Alpha:</b></td> |
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<td width="35"></td><td></td> |
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<tr> |
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<td valign="top"> |
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<pre>mips_instr_addiu: |
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ldq t1,8(a1) |
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ldq t2,24(a1) |
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ldq t3,16(a1) |
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ldq t0,0(t1) |
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addl t0,t2,t0 |
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stq t0,0(t3) |
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ret</pre> |
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</td> |
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<td></td> |
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<td valign="top"> |
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<pre>mips32_instr_addiu: |
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ldq t2,8(a1) |
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ldq t0,24(a1) |
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ldq t3,16(a1) |
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ldl t1,0(t2) |
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addq t0,t1,t0 |
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stl t0,0(t3) |
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ret</pre> |
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</td> |
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</tr> |
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<tr><td><b><br>GCC 3.4.4 on AMD64:</b></td> |
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<tr> |
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<td valign="top"> |
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<pre>mips_instr_addiu: |
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mov 0x8(%rsi),%rdx |
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mov 0x18(%rsi),%rax |
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mov 0x10(%rsi),%rcx |
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add (%rdx),%eax |
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cltq |
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mov %rax,(%rcx) |
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retq</pre> |
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</td> |
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<td></td> |
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<td valign="top"> |
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<pre>mips32_instr_addiu: |
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mov 0x8(%rsi),%rcx |
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mov 0x10(%rsi),%rdx |
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mov (%rcx),%eax |
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add 0x18(%rsi),%eax |
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mov %eax,(%rdx) |
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retq</pre> |
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</td> |
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</tr> |
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<tr><td><b><br>GCC 4.0.1 on i386:</b></td> |
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<tr> |
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<td valign="top"> |
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<pre>mips_instr_addiu: |
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mov 0x8(%esp),%eax |
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mov 0x8(%eax),%ecx |
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mov 0x4(%eax),%edx |
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mov 0xc(%eax),%eax |
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add (%edx),%eax |
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mov %eax,(%ecx) |
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cltd |
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mov %edx,0x4(%ecx) |
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ret</pre> |
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</td> |
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<td></td> |
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<td valign="top"> |
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<pre>mips32_instr_addiu: |
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mov 0x8(%esp),%eax |
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mov 0x8(%eax),%ecx |
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mov 0x4(%eax),%edx |
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mov 0xc(%eax),%eax |
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add (%edx),%eax |
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mov %eax,(%ecx) |
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ret</pre> |
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</td> |
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</tr> |
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</table></center> |
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There is some code for 64-bit (and 32-bit) POWER/PowerPC emulation, enough |
<p>On 64-bit hosts, there is not much difference, but on 32-bit hosts (and |
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to run "Hello World", but not enough to run complete operating systems. |
to some extent on AMD64), the difference is enough to make it worthwhile. |
|
This mode isn't really working yet. |
|
394 |
|
|
395 |
|
|
396 |
<h4>Other CPU types:</h4> |
<p><b>Performance:</b> |
397 |
|
|
398 |
|
<p>The performance of using this kind of runnable IR is obviously lower |
399 |
|
than what can be achieved by emulators using native code generation, but |
400 |
|
can be significantly higher than using a naive fetch-decode-execute |
401 |
|
interpretation loop. In my opinion, using a runnable IR is an interesting |
402 |
|
compromise. |
403 |
|
|
404 |
|
<p>The overhead per emulated instruction is usually around or below |
405 |
|
approximately 10 host instructions. This is very much dependent on your |
406 |
|
host architecture and what compiler and compiler switches you are using. |
407 |
|
Added to this instruction count is (of course) also the C code used to |
408 |
|
implement each specific instruction. |
409 |
|
|
410 |
|
<p><b>Instruction Combinations:</b> |
411 |
|
|
412 |
|
<p>Short, common instruction sequences can sometimes be replaced by a |
413 |
|
"compound" instruction. An example could be a compare instruction followed |
414 |
|
by a conditional branch instruction. The advantages of instruction |
415 |
|
combinations are that |
416 |
|
<ul> |
417 |
|
<li>the amortized overhead per instruction is slightly reduced, and |
418 |
|
<p> |
419 |
|
<li>the host's compiler can make a good job at optimizing the common |
420 |
|
instruction sequence. |
421 |
|
</ul> |
422 |
|
|
423 |
|
<p>The special cases where instruction combinations give the most gain |
424 |
|
are in the cores of string/memory manipulation functions such as |
425 |
|
<tt>memset()</tt> or <tt>strlen()</tt>. The core loop can then (at least |
426 |
|
to some extent) be replaced by a native call to the equivalent function. |
427 |
|
|
428 |
|
<p>The implementations of compound instructions still keep track of the |
429 |
|
number of executed instructions, etc. When single-stepping, these |
430 |
|
translations are invalidated, and replaced by normal instruction calls |
431 |
|
(one per emulated instruction). |
432 |
|
|
433 |
|
<p><b>Native Code Back-ends:</b> |
434 |
|
|
435 |
|
<p>In theory, it will be possible to implement native code generation, |
436 |
|
similar to what is used in high-performance emulators such as QEMU, |
437 |
|
as long as that generated code abides to the C ABI on the host. |
438 |
|
|
439 |
|
<p>However, since I wanted to make sure that GXemul works without such |
440 |
|
native code back-ends, there are no implemented backends in this release. |
441 |
|
|
442 |
|
<p>(There is a place-holder in the source code for native code generation, |
443 |
|
which can be used for experiments, but it does not contain any working |
444 |
|
code at the moment.) |
445 |
|
|
|
Some other CPU architectures (such as x86) can also be partially emulated. |
|
|
These are not enabled by default though, because of their unstable-ness. |
|
446 |
|
|
447 |
|
|
448 |
|
|
453 |
<h3>Emulation accuracy:</h3> |
<h3>Emulation accuracy:</h3> |
454 |
|
|
455 |
GXemul is an instruction-level emulator; things that would happen in |
GXemul is an instruction-level emulator; things that would happen in |
456 |
several steps within a real CPU are not taken into account (eg. pipe-line |
several steps within a real CPU are not taken into account (e.g. pipe-line |
457 |
stalls or out-of-order execution). Still, instruction-level accuracy seems |
stalls or out-of-order execution). Still, instruction-level accuracy seems |
458 |
to be enough to be able to run complete guest operating systems inside the |
to be enough to be able to run complete guest operating systems inside the |
459 |
emulator. |
emulator. |
460 |
|
|
461 |
<p> |
<p>The existance of instruction and data caches is "faked" to let |
462 |
Caches are by default not emulated. In some cases, the existance of caches |
operating systems think that they are there, but for all practical |
463 |
is "faked" to let operating systems think that they are there. (There is |
purposes, these caches are non-working. |
464 |
some old code for R2000/R3000 caches, but it has probably suffered from |
|
465 |
bitrot by now.) |
<p>The emulator is in general <i>not</i> timing-accurate, neither at the |
466 |
|
instruction level nor on any higher level. An attempt is made to let |
467 |
|
emulated clocks run at the same speed as the host (i.e. an emulated timer |
468 |
|
running at 100 Hz will interrupt around 100 times per real second), but |
469 |
|
since the host speed may vary, e.g. because of other running processes, |
470 |
|
there is no guarantee as to how many instructions will be executed in |
471 |
|
each of these 100 Hz cycles. |
472 |
|
|
473 |
|
<p>If the host is very slow, the emulated clocks might even lag behind |
474 |
|
the real-world clock. |
475 |
|
|
|
<p> |
|
|
The emulator is <i>not</i> timing-accurate. It can be run in a |
|
|
"deterministic" mode, <tt><b>-D</b></tt>. The meaning of deterministic is |
|
|
simply that running two emulations with the same settings will result in |
|
|
identical runs. Obviously, this requires that no user interaction is |
|
|
taking place, and that clock speeds are fixed with the <tt><b>-I</b></tt> |
|
|
option. (Deterministic in this case does <i>not</i> mean that the emulation |
|
|
will be identical to some actual real-world machine.) |
|
476 |
|
|
477 |
|
|
478 |
|
|
487 |
|
|
488 |
<p> |
<p> |
489 |
<ul> |
<ul> |
490 |
<li><b>DECstation 5000/200</b> ("3max") |
<li><b><u>ARM</u></b> |
491 |
<br>Serial controller (including keyboard and mouse), ethernet, |
<ul> |
492 |
SCSI, and graphical framebuffers. |
<li><b>CATS</b> (<a href="guestoses.html#netbsdcatsinstall">NetBSD/cats</a>, |
493 |
|
<a href="guestoses.html#openbsdcatsinstall">OpenBSD/cats</a>) |
494 |
|
<li><b>IQ80321</b> (<a href="guestoses.html#netbsdevbarminstall">NetBSD/evbarm</a>) |
495 |
|
<li><b>NetWinder</b> (<a href="guestoses.html#netbsdnetwinderinstall">NetBSD/netwinder</a>) |
496 |
|
</ul> |
497 |
<p> |
<p> |
498 |
<li><b>Acer Pica-61</b> (an ARC machine) |
<li><b><u>MIPS</u></b> |
499 |
<br>Serial controller, "VGA" text console, and SCSI. |
<ul> |
500 |
|
<li><b>DECstation 5000/200</b> (<a href="guestoses.html#netbsdpmaxinstall">NetBSD/pmax</a>, |
501 |
|
<a href="guestoses.html#openbsdpmaxinstall">OpenBSD/pmax</a>, |
502 |
|
<a href="guestoses.html#ultrixinstall">Ultrix</a>, |
503 |
|
<a href="guestoses.html#declinux">Linux/DECstation</a>, |
504 |
|
<a href="guestoses.html#sprite">Sprite</a>) |
505 |
|
<li><b>Acer Pica-61</b> (<a href="guestoses.html#netbsdarcinstall">NetBSD/arc</a>) |
506 |
|
<li><b>NEC MobilePro 770, 780, 800, 880</b> (<a href="guestoses.html#netbsdhpcmipsinstall">NetBSD/hpcmips</a>) |
507 |
|
<li><b>Cobalt</b> (<a href="guestoses.html#netbsdcobaltinstall">NetBSD/cobalt</a>) |
508 |
|
<li><b>Malta</b> (<a href="guestoses.html#netbsdevbmipsinstall">NetBSD/evbmips</a>, Linux/Malta <font color="#0000e0">(<super>*1</super>)</font>) |
509 |
|
<li><b>Algorithmics P5064</b> (<a href="guestoses.html#netbsdalgorinstall">NetBSD/algor</a>) |
510 |
|
<li><b>SGI O2 (aka IP32)</b> <font color="#0000e0">(<super>*2</super>)</font> |
511 |
|
(<a href="guestoses.html#netbsdsgimips">NetBSD/sgi</a>) |
512 |
|
</ul> |
513 |
<p> |
<p> |
514 |
<li><b>NEC MobilePro 770, 780, 800, and 880</b> (HPCmips machines) |
<li><b><u>PowerPC</u></b> |
515 |
<br>Framebuffer, keyboard, and a PCMCIA IDE controller. |
<ul> |
516 |
|
<li><b>IBM 6050/6070 (PReP, PowerPC Reference Platform)</b> (<a href="guestoses.html#netbsdprepinstall">NetBSD/prep</a>) |
517 |
|
<li><b>MacPPC (generic "G4" Macintosh)</b> (<a href="guestoses.html#netbsdmacppcinstall">NetBSD/macppc</a>) |
518 |
|
</ul> |
519 |
<p> |
<p> |
520 |
<li><b>Cobalt</b> |
<li><b><u>SuperH</u></b> |
521 |
<br>Serial controller and PCI IDE. |
<ul> |
522 |
|
<li><b>Sega Dreamcast</b> (<a href="dreamcast.html#netbsd_generic_md">NetBSD/dreamcast</a>) |
523 |
|
</ul> |
524 |
</ul> |
</ul> |
525 |
|
|
526 |
<p> |
<p> |
527 |
There is code in GXemul for emulation of many other machine types; |
<small><font color="#0000e0">(<super>*1</super>)</font> = |
528 |
the degree to which these work range from "almost" being able to run |
Linux/Malta may be run as a guest OS, however I have not yet found any stable |
529 |
a complete OS, to almost completely unsupported (perhaps just enough |
URL to pre-compiled Linux/Malta kernels. Thus, Linux/Malta emulation is not |
530 |
support to output a few boot messages via serial console). |
tested for every release of the emulator; sometimes it works, sometimes |
531 |
|
it doesn't.</small> |
532 |
<p> |
|
533 |
In addition to emulating real machines, there is also a "test-machine". |
<br><small><font color="#0000e0">(<super>*2</super>)</font> = |
534 |
A test-machine consists of one or more CPUs and a few experimental |
SGI O2 emulation is enough for root-on-nfs, but not for disk boot.</small> |
535 |
devices such as: |
|
536 |
|
|
537 |
|
<p>There is code in GXemul for emulation of many other machine types; the |
538 |
|
degree to which these work range from almost being able to run a complete |
539 |
|
OS, to almost completely unsupported (perhaps just enough support to |
540 |
|
output a few boot messages via serial console). |
541 |
|
|
542 |
|
<p>In addition to emulating real machines, there is also a "test-machine". |
543 |
|
A test-machine consists of one or more CPUs and a few experimental devices |
544 |
|
such as: |
545 |
|
|
546 |
<p> |
<p> |
547 |
<ul> |
<ul> |
548 |
<li>a console I/O device (putchar() and getchar()...) |
<li>a console I/O device (putchar() and getchar()...) |
549 |
<li>an inter-processor communication device, for SMP experiments |
<li>an inter-processor communication device, for SMP experiments |
550 |
<li>a very simple linear framebuffer device (for graphics output) |
<li>a very simple linear framebuffer device (for graphics output) |
551 |
|
<li>a simple disk controller |
552 |
|
<li>a simple ethernet controller |
553 |
|
<li>a real-time clock device |
554 |
</ul> |
</ul> |
555 |
|
|
556 |
<p> |
<p>This mode is useful if you wish to run experimental code, but do not |
|
This mode is useful if you wish to run experimental code, but do not |
|
557 |
wish to target any specific real-world machine type, for example for |
wish to target any specific real-world machine type, for example for |
558 |
educational purposes. |
educational purposes. |
559 |
|
|
560 |
<p> |
<p>You can read more about these experimental devices <a |
561 |
You can read more about these experimental devices |
href="experiments.html#expdevices">here</a>. |
|
<a href="experiments.html#expdevices">here</a>. |
|
|
|
|
|
|
|
562 |
|
|
563 |
|
|
564 |
|
|
565 |
|
|
566 |
|
|
|
<p><br> |
|
|
<a name="guestos"></a> |
|
|
<h3>Which guest OSes are possible to run?</h3> |
|
|
|
|
|
This table lists the guest OSes that run well enough to be considered |
|
|
working in the emulator. They can boot from a harddisk image and be |
|
|
interacted with similar to a real machine. |
|
|
|
|
|
<p> |
|
|
<center><table border="0"> |
|
|
<tr> |
|
|
<td width="10"></td> |
|
|
<td align="center"><a href="20050317-example.png"><img src="20050317-example_small.png"></a></td> |
|
|
<td width="15"></td> |
|
|
<td><a href="http://www.netbsd.org/Ports/pmax/">NetBSD/pmax</a> |
|
|
<br>DECstation 5000/200</td> |
|
|
<td width="30"></td> |
|
|
<td align="center"><a href="20041024-netbsd-arc-installed.gif"><img src="20041024-netbsd-arc-installed_small.gif"></a></td> |
|
|
<td width="15"></td> |
|
|
<td><a href="http://www.netbsd.org/Ports/arc/">NetBSD/arc</a> |
|
|
<br>Acer Pica-61</td> |
|
|
|
|
|
</tr> |
|
|
|
|
|
<tr><td height="10"></td></tr> |
|
|
|
|
|
<tr> |
|
|
<td></td> |
|
|
<td align="center"><a href="openbsd-pmax-20040710.png"><img src="openbsd-pmax-20040710_small.png"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.openbsd.org/pmax.html">OpenBSD/pmax</a> |
|
|
<br>DECstation 5000/200</td> |
|
|
<td></td> |
|
|
<td align="center"><a href="20041024-openbsd-arc-installed.gif"><img src="20041024-openbsd-arc-installed_small.gif"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.openbsd.org/arc.html">OpenBSD/arc</a> |
|
|
<br>Acer Pica-61</td> |
|
|
</tr> |
|
|
|
|
|
<tr><td height="10"></td></tr> |
|
|
|
|
|
<tr> |
|
|
<td></td> |
|
|
<td align="center"><a href="ultrix4.5-20040706.png"><img src="ultrix4.5-20040706_small.gif"></a></td> |
|
|
<td></td> |
|
|
<td>Ultrix/RISC<br>DECstation 5000/200</td> |
|
|
<td></td> |
|
|
<td align="center"><a href="20041213-debian_4.png"><img src="20041213-debian_4_small.gif"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.debian.org/">Debian GNU/Linux</a> <super>*</super> |
|
|
<br>DECstation 5000/200</td> |
|
|
</tr> |
|
|
|
|
|
<tr><td height="10"></td></tr> |
|
|
|
|
|
<tr> |
|
|
<td></td> |
|
|
<td align="center"><a href="sprite-20040711.png"><img src="sprite-20040711_small.png"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.cs.berkeley.edu/projects/sprite/retrospective.html">Sprite</a> |
|
|
<br>DECstation 5000/200</td> |
|
|
<td></td> |
|
|
<td align="center"><a href="20041129-redhat_mips.png"><img src="20041129-redhat_mips_small.png"></a></td> |
|
|
<td></td> |
|
|
<td>Redhat Linux <super>*</super> |
|
|
<br>DECstation 5000/200</td> |
|
|
</tr> |
|
|
|
|
|
<tr><td height="10"></td></tr> |
|
|
|
|
|
<tr> |
|
|
<td></td> |
|
|
<td align="center"><a href="20050427-netbsd-hpcmips-2.png"><img src="20050427-netbsd-hpcmips-2_small.png"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.netbsd.org/Ports/hpcmips/">NetBSD/hpcmips</a> |
|
|
<br>NEC MobilePro 770, 780, 800, 880</td> |
|
|
<td></td> |
|
|
<td align="center"><a href="20050413-netbsd-cobalt.png"><img src="20050413-netbsd-cobalt_small.png"></a></td> |
|
|
<td></td> |
|
|
<td><a href="http://www.netbsd.org/Ports/cobalt/">NetBSD/cobalt</a> |
|
|
<br>Cobalt</td> |
|
|
</tr> |
|
|
|
|
|
</table></center> |
|
|
|
|
|
|
|
|
<p><br> |
|
|
|
|
|
<super>*</super> Although Linux runs under DECstation emulation, the |
|
|
default 2.4.27 kernel in Debian GNU/Linux does not support keyboards on |
|
|
the 5000/200 (the specific DECstation model being emulated), so when the |
|
|
login prompt is reached you cannot interact with the system. Kaj-Michael |
|
|
Lang has compiled and made available a newer kernel from the current |
|
|
mips-linux development tree. You can find it here: <a |
|
|
href="http://home.tal.org/~milang/o2/kernels/">http://home.tal.org/~milang/o2/kernels</a>/<a |
|
|
href="http://home.tal.org/~milang/o2/kernels/vmlinux-2.4.29-rc2-r3k-mipsel-decstation">vmlinux-2.4.29-rc2-r3k-mipsel-decstation</a> |
|
|
This newer kernel supports keyboard input, but it does not have Debian's |
|
|
ethernet patches, so you will not be able to use keyboard/framebuffer |
|
|
<i>and</i> networking at the same time. |
|
|
|
|
567 |
|
|
568 |
</body> |
</body> |
569 |
</html> |
</html> |