/[gxemul]/trunk/doc/intro.html
This is repository of my old source code which isn't updated any more. Go to git.rot13.org for current projects!
ViewVC logotype

Diff of /trunk/doc/intro.html

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 32 by dpavlin, Mon Oct 8 16:20:58 2007 UTC revision 44 by dpavlin, Mon Oct 8 16:22:56 2007 UTC
# Line 4  Line 4 
4  <table border=0 width=100% bgcolor="#d0d0d0"><tr>  <table border=0 width=100% bgcolor="#d0d0d0"><tr>
5  <td width=100% align=center valign=center><table border=0 width=100%><tr>  <td width=100% align=center valign=center><table border=0 width=100%><tr>
6  <td align="left" valign=center bgcolor="#d0efff"><font color="#6060e0" size="6">  <td align="left" valign=center bgcolor="#d0efff"><font color="#6060e0" size="6">
7  <b>Gavare's eXperimental Emulator:</b></font><br>  <b>GXemul:</b></font>&nbsp;&nbsp;
8  <font color="#000000" size="6"><b>Introduction</b>  <font color="#000000" size="6"><b>Introduction</b>
9  </font></td></tr></table></td></tr></table><p>  </font></td></tr></table></td></tr></table><p>
10    
11  <!--  <!--
12    
13  $Id: intro.html,v 1.100 2006/11/04 06:40:20 debug Exp $  $Id: intro.html,v 1.125 2007/06/30 14:02:02 debug Exp $
14    
15  Copyright (C) 2003-2006  Anders Gavare.  All rights reserved.  Copyright (C) 2003-2007  Anders Gavare.  All rights reserved.
16    
17  Redistribution and use in source and binary forms, with or without  Redistribution and use in source and binary forms, with or without
18  modification, are permitted provided that the following conditions are met:  modification, are permitted provided that the following conditions are met:
# Line 52  SUCH DAMAGE. Line 52  SUCH DAMAGE.
52    <li><a href="#build">How to compile/build the emulator</a>    <li><a href="#build">How to compile/build the emulator</a>
53    <li><a href="#run">How to run the emulator</a>    <li><a href="#run">How to run the emulator</a>
54    <li><a href="#cpus">Which processor architectures does GXemul emulate?</a>    <li><a href="#cpus">Which processor architectures does GXemul emulate?</a>
55    <li><a href="#hosts">Which host architectures are supported?</a>    <li><a href="#hosts">Which host architectures/platforms are supported?</a>
   <li><a href="#translation">What kind of translation does GXemul use?</a>  
56    <li><a href="#accuracy">Emulation accuracy</a>    <li><a href="#accuracy">Emulation accuracy</a>
57    <li><a href="#emulmodes">Which machines does GXemul emulate?</a>    <li><a href="#emulmodes">Which machines does GXemul emulate?</a>
58  </ul>  </ul>
# Line 68  SUCH DAMAGE. Line 67  SUCH DAMAGE.
67  <a name="overview"></a>  <a name="overview"></a>
68  <h3>Overview:</h3>  <h3>Overview:</h3>
69    
70  GXemul is an experimental instruction-level machine emulator. Several  GXemul is a framework for full-system computer architecture emulation.
71  emulation modes are available. In some modes, processors and surrounding  Several processor architectures and machine types have been implemented.
72  hardware components are emulated well enough to let unmodified operating  It is working well enough to allow <a href="#emulmodes">unmodified
73  systems (e.g. NetBSD) run as if they were running on a real machine.  "guest" operating systems to run inside the emulator</a>, as if they were
74    running on real hardware.
75    
76    <p>The emulator emulates (networks of) real machines. The machines may
77    consist of <a
78    href="http://en.wikipedia.org/wiki/ARM_architecture">ARM</a>, <a
79    href="http://en.wikipedia.org/wiki/MIPS_architecture">MIPS</a>, <a
80    href="http://en.wikipedia.org/wiki/Powerpc">PowerPC</a>, and <a
81    href="http://en.wikipedia.org/wiki/SuperH">SuperH</a> processors, and
82    various surrounding hardware components such as framebuffers, busses,
83    interrupt controllers, ethernet controllers, disk controllers, and serial
84    port controllers.
85    
86    <p>GXemul, including the dynamic translation system, is implemented in
87    portable
88    <a href="http://en.wikipedia.org/wiki/C_(programming_language)">C</a>,
89    which means that the emulator will run on practically any 64-bit or 32-bit
90    <a href="http://en.wikipedia.org/wiki/Unix-like">Unix-like</a> systems,
91    with few or no modifications.
92    
93  <p>Devices and processors are not simulated with 100% accuracy. They are  <p>Devices and processors are not simulated with 100% accuracy. They are
94  only ``faked'' well enough to allow guest operating systems to run without  only "faked" well enough to allow guest operating systems to run without
95  complaining too much. Still, the emulator could be of interest for  complaining too much. Still, the emulator could be of interest for
96  academic research and experiments, such as when learning how to write  academic research and experiments, such as when learning how to write
97  operating system code.  operating system code.
98    
 <p>The emulator is written in C, does not depend on third-party libraries,  
 and should compile and run on most 64-bit and 32-bit Unix-like systems.  
   
99  <p>The emulator contains code which tries to emulate the workings of CPUs  <p>The emulator contains code which tries to emulate the workings of CPUs
100  and surrounding hardware found in real machines, but it does not contain  and surrounding hardware found in real machines, but it does not contain
101  any ROM code. You will need some form of program (in binary form) to run  any ROM code. You will need some form of program (in binary form) to run
102  in the emulator. For many emulation modes, PROM calls are handled by the  in the emulator. For some emulation modes, PROM calls are handled by the
103  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.
104    
105  <p>You can use pre-compiled kernels (for example NetBSD kernels, or  <p>You can use pre-compiled kernels (for example <a href="http://www.netbsd.org/">NetBSD</a>
106  Linux), or other programs that are in binary format, and in some cases  kernels, or Linux), or other programs that are in binary format, and in some cases
107  even actual ROM images. A couple of different file formats are supported  even actual ROM images. A couple of different file formats are supported:
108  (ELF, a.out, ECOFF, SREC, and raw binaries).  <a href="http://en.wikipedia.org/wiki/Executable_and_Linkable_Format">ELF</a>,
109    <a href="http://en.wikipedia.org/wiki/A.out">a.out</a>,
110    <a href="http://en.wikipedia.org/wiki/COFF">COFF</a>/<a href="http://en.wikipedia.org/wiki/ECOFF">ECOFF</a>,
111    <a href="http://en.wikipedia.org/wiki/SREC_%28file_format%29">SREC</a>, and raw binaries.
112    
113  <p>If you do not have a kernel as a separate file, but you have a bootable  <p>If you do not have a kernel as a separate file, but you have a bootable
114  disk image, then it is sometimes possible to boot directly from that  disk image, then it is sometimes possible to boot directly from that
115  image. (This works for example with DECstation emulation, or when booting  image. This works for example with DECstation emulation, <a href="dreamcast.html">Dreamcast
116  from ISO9660 CDROM images.)  emulation</a>, or when booting from generic <a href="http://en.wikipedia.org/wiki/ISO9660">ISO9660</a>
117    CDROM images if the kernel is included in the image as a plain file.
118    
119  <p>Thanks to (in no specific order) Joachim Buss, Olivier Houchard, Juli  <p>Thanks to (in no specific order) Joachim Buss, Olivier Houchard, Juli
120  Mallett, Juan Romero Pardines, Alec Voropay, Göran Weinholt, Alexander  Mallett, Juan Romero Pardines, Carl van Schaik, Miod Vallat, Alec Voropay,
121  Yurchenko, and everyone else who has provided me with feedback.  Göran Weinholt, Alexander Yurchenko, and everyone else who has provided me
122    with feedback.
123    
124    
125    
# Line 134  way, for example by writing additional d Line 153  way, for example by writing additional d
153  notes. I have not done this, since I do not plan on making distributions  notes. I have not done this, since I do not plan on making distributions
154  without source code. You need to check all individual files for details.  without source code. You need to check all individual files for details.
155  The "easiest way out" if you plan to redistribute code from GXemul is, of  The "easiest way out" if you plan to redistribute code from GXemul is, of
156  course, to let it remain open source and simply supply the source code.  course, to let it remain Free Software and simply include the source code.
157    
158  <p>In case you want to reuse parts of GXemul, but you need to do that  <p>In case you want to reuse parts of GXemul, but you need to do that
159  under a different license (e.g. the GPL), then contact me and I might  under a different license (e.g. the
160  re-license/dual-license files on a case-by-case basis.  <a href="http://www.gnu.org/licenses/gpl.html">GPL</a>), then contact me and
161    I can probably re-license/dual-license files on a case-by-case basis.
162    
163    
164    
# Line 158  Uncompress the .tar.gz distribution file Line 178  Uncompress the .tar.gz distribution file
178  specific libraries to build, however, if you build on a system which does  specific libraries to build, however, if you build on a system which does
179  not have X11 libraries installed, some functionality will be lost.  not have X11 libraries installed, some functionality will be lost.
180    
181  <p>The emulator's performance is highly dependent on both runtime settings  <p>The emulator's performance is highly dependent on both runtime settings
182  and on compiler settings, so you might want to experiment with different  and on compiler settings, so you might want to experiment with using
183  CC and CFLAGS environment variable values. For example, on an AMD Athlon  different <tt>CC</tt> and <tt>CFLAGS</tt> environment variable values when
184  host, you might want to try setting <tt>CFLAGS</tt> to <tt>-march=athlon</tt>  running the <tt>configure</tt> script.
185  before running <tt>configure</tt>.  
186    <p>On some platforms, it is possible that building GXemul will fail
187    because of too high optimization. When using GCC (the GNU compiler),
188    <tt>-O3</tt> is the default optimization level. This works fine on e.g.
189    amd64 and i386 systems, but on some more uncommon platforms, <tt>-O3</tt>
190    might trigger internal bugs in GCC itself. If this happens, try setting
191    <tt>CFLAGS</tt> to <tt>-O2</tt> before running <tt>./configure</tt>, and
192    try again,
193    
194    <p>Note that there is no <tt>make install</tt> functionality; package
195    maintainers for individual operating systems solve this for their
196    corresponding OSes.
197    
198    
199    
# Line 179  Running <tt><b>gxemul</b></tt> without a Line 210  Running <tt><b>gxemul</b></tt> without a
210  <b><tt>-h</tt></b> or <b><tt>-H</tt></b> command line options) will  <b><tt>-h</tt></b> or <b><tt>-H</tt></b> command line options) will
211  display a help message.  display a help message.
212    
213  <p>  <p>To get some ideas about what is possible to run in the emulator, please
 To get some ideas about what is possible to run in the emulator, please  
214  read the section about <a href="guestoses.html">installing "guest"  read the section about <a href="guestoses.html">installing "guest"
215  operating systems</a>. If you are interested in using the emulator to  operating systems</a>. The most straight forward guest operating to
216  develop code on your own, then you should also read the section about  install is NetBSD/pmax; the instructions provided <a
217  <a href="experiments.html#hello">Hello World</a>.  href="guestoses.html#netbsdpmaxinstall">here</a> should let you install
218    NetBSD/pmax in a way very similar to how it is done on a real DECstation.
219    
220    <p>If you are interested in using the emulator to develop code on your
221    own, then you should also read the section about <a
222    href="experiments.html#hello">Hello World</a>.
223    
224  <p>  <p>To exit the emulator, type CTRL-C to enter the
 To exit the emulator, type CTRL-C to enter the  
225  single-step debugger, and then type <tt><b>quit</b></tt>.  single-step debugger, and then type <tt><b>quit</b></tt>.
226    
227  <p>  <p>If you are starting an emulation by entering settings directly on the
228  If you are starting an emulation by entering settings directly on the  command line, and you are not using the <tt><b>-x</b></tt> option, then
229  command line, and you are not using the <tt><b>-x</b></tt> option, then all  all terminal input and output will go to the main controlling terminal.
 terminal input and output will go to the main controlling terminal.  
230  CTRL-C is used to break into the debugger, so in order to send CTRL-C to  CTRL-C is used to break into the debugger, so in order to send CTRL-C to
231  the running (emulated) program, you may use CTRL-B.  the running (emulated) program, you may use CTRL-B. (This should be a
232  (This should be a reasonable compromise to allow the emulator to be usable  reasonable compromise to allow the emulator to be usable even on systems
233  even on systems without X Windows.)  without X Windows.)
234    
235  <p>  <p>There is no way to send an actual CTRL-B to the emulated program, when
236  There is no way to send an actual CTRL-B to the emulated program, when  typing in the main controlling terminal window. The solution is to either
237  typing in the main controlling terminal window. The solution is to either  use <a href="configfiles.html">configuration files</a>, or use
 use <a href="configfiles.html">configuration files</a>, or use  
238  <tt><b>-x</b></tt>. Both these solutions cause new xterms to be opened for  <tt><b>-x</b></tt>. Both these solutions cause new xterms to be opened for
239  each emulated serial port that is written to. CTRL-B and CTRL-C both have  each emulated serial port that is written to. CTRL-B and CTRL-C both have
240  their original meaning in those xterm windows.  their original meaning in those xterm windows.
# Line 216  their original meaning in those xterm wi Line 248  their original meaning in those xterm wi
248  <h3>Which processor architectures does GXemul emulate?</h3>  <h3>Which processor architectures does GXemul emulate?</h3>
249    
250  The architectures that are emulated well enough to let at least one  The architectures that are emulated well enough to let at least one
251  guest operating system run (per architecture) are ARM, MIPS, PowerPC,  guest operating system run (per architecture) are
252  and SuperH.  <a href="http://en.wikipedia.org/wiki/ARM_architecture">ARM</a>,  
253    <a href="http://en.wikipedia.org/wiki/MIPS_architecture">MIPS</a>,  
254    <a href="http://en.wikipedia.org/wiki/Powerpc">PowerPC</a>, and  
255    <a href="http://en.wikipedia.org/wiki/SuperH">SuperH</a>.
256    
257    <p>Please read the sections about <a href="#emulmodes">emulation
258    modes</a> and <a href="guestoses.html">guest operating
259    systems</a> for more information about the machines and operating systems,
260    respectively, that can be considered "working" in the emulator.
261    
262    <p>(There is some code in GXemul for emulation of other architectures, but
263    they are not stable or complete enough to be listed among the "working"
264    architectures.)
265    
266    
267    
# Line 226  and SuperH. Line 270  and SuperH.
270    
271  <p><br>  <p><br>
272  <a name="hosts"></a>  <a name="hosts"></a>
273  <h3>Which host architectures are supported?</h3>  <h3>Which host architectures/platforms are supported?</h3>
274    
275  GXemul should compile and run on any modern host architecture (64-bit or  GXemul should compile and run on any modern host architecture (64-bit or
276  32-bit word-length).  32-bit word-length). I generally test it on
277    <a href="http://www.freebsd.org/platforms/amd64.html">FreeBSD/amd64</a> 6.x,
278    <a href="http://www.freebsd.org/platforms/alpha.html">FreeBSD/alpha</a> 4.x,
279    sometimes also on Linux (various platforms), and every
280    now and then also on <a href="http://www.netbsd.org/">NetBSD</a> or
281    <a href="http://www.openbsd.org/">OpenBSD</a> inside the emulator itself
282    (various platforms).
283    
284    <p>Note 1: The <a href="translation.html">dynamic translation</a> engine
285    does <i>not</i> require backends for native code generation to be written
286    for each individual host architecture; the intermediate representation
287    that the dyntrans system uses can be executed on any host architecture.
288    
289    <p>Note 2: Although GXemul may build and run on non-Unix-like platforms,
290    such as <a href="http://www.cygwin.com/">Cygwin</a>, Unix-like systems are
291    the primary platform. Some functionality may be lost when running on Cygwin.
292    
 <p>(The dynamic translation engine translates into an intermediate  
 representation, but not currently into native code. This means that there  
 is no need for per-host architecture backend code.)  
293    
294    
295    
296    
297    
 <p><br>  
 <a name="translation"></a>  
 <h3>What kind of translation does GXemul use?</h3>  
   
 <b>Static vs. dynamic:</b>  
   
 <p>In order to support guest operating systems, which can overwrite old  
 code pages in memory with new code, it is necessary to translate code  
 dynamically. It is not possible to do a "one-pass" (static) translation.  
 Self-modifying code and Just-in-Time compilers running inside  
 the emulator are other things that would not work with a static  
 translator. GXemul is a dynamic translator. However, it does not  
 necessarily translate into native code, like many other emulators.  
   
 <p><b>"Runnable" Intermediate Representation:</b>  
   
 <p>Dynamic translators usually translate from the emulated architecture  
 (e.g. MIPS) into a kind of <i>intermediate representation</i> (IR), and then  
 to native code (e.g. AMD64 or x86 code). Since one of my main goals for  
 GXemul is to keep everything as portable as possible, I have tried to make  
 sure that the IR is something which can be executed regardless of whether  
 the final step (translation from IR to native code) has been implemented  
 or not.  
   
 <p>The IR in GXemul consists of arrays of pointers to functions, and a few  
 arguments which are passed along to those functions. The functions are  
 implemented in either manually hand-coded C, or automatically generated C.  
 In any case, this is all statically linked into the GXemul binary at link  
 time.  
   
 <p>Here is a simplified diagram of how these arrays work.  
   
 <p><center><img src="simplified_dyntrans.png"></center>  
   
 <p>There is one instruction call slot for every possible program counter  
 location. In the MIPS case, instruction words are 32 bits in length,  
 and pages are (usually) 4 KB large, resulting in 1024 instruction call  
 slots. After the last of these instruction calls, there is an additional  
 call to a special "end of page" function (which doesn't count as an executed  
 instruction). This function switches to the first instruction  
 on the next virtual page (which might cause exceptions, etc).  
   
 <p>The complexity of individual instructions vary. A simple example of  
 what an instruction can look like is the MIPS <tt>addiu</tt> instruction:  
 <pre>  
         X(addiu)  
         {  
                 reg(ic->arg[1]) = (int32_t)  
                     ((int32_t)reg(ic->arg[0]) + (int32_t)ic->arg[2]);  
         }  
 </pre>  
   
 <p>It stores the result of a 32-bit addition of the register at arg[0]  
 with the immediate value arg[2] (treating both as signed 32-bit  
 integers) into register arg[1]. If the emulated CPU is a 64-bit CPU,  
 then this will store a correctly sign-extended value into arg[1].  
 If it is a 32-bit CPU, then only the lowest 32 bits will be stored,  
 and the high part ignored. <tt>X(addiu)</tt> is expanded to  
 <tt>mips_instr_addiu</tt> in the 64-bit case, and <tt>mips32_instr_addiu</tt>  
 in the 32-bit case. Both are compiled into the GXemul executable; no code  
 is created during run-time.  
   
 <p>Here are examples of what the <tt>addiu</tt> instruction actually  
 looks like when it is compiled, on various host architectures:  
   
 <p><center><table border="0">  
     <tr><td><b>GCC 4.0.1 on Alpha:</b></td>  
         <td width="35"></td><td></td>  
     <tr>  
         <td valign="top">  
 <pre>mips_instr_addiu:  
      ldq     t1,8(a1)  
      ldq     t2,24(a1)  
      ldq     t3,16(a1)  
      ldq     t0,0(t1)  
      addl    t0,t2,t0  
      stq     t0,0(t3)  
      ret</pre>  
         </td>  
         <td></td>  
         <td valign="top">  
 <pre>mips32_instr_addiu:  
      ldq     t2,8(a1)  
      ldq     t0,24(a1)  
      ldq     t3,16(a1)  
      ldl     t1,0(t2)  
      addq    t0,t1,t0  
      stl     t0,0(t3)  
      ret</pre>  
         </td>  
     </tr>  
   
     <tr><td><b><br>GCC 3.4.4 on AMD64:</b></td>  
     <tr>  
         <td valign="top">  
 <pre>mips_instr_addiu:  
      mov    0x8(%rsi),%rdx  
      mov    0x18(%rsi),%rax  
      mov    0x10(%rsi),%rcx  
      add    (%rdx),%eax  
      cltq  
      mov    %rax,(%rcx)  
      retq</pre>  
         </td>  
         <td></td>  
         <td valign="top">  
 <pre>mips32_instr_addiu:  
      mov    0x8(%rsi),%rcx  
      mov    0x10(%rsi),%rdx  
      mov    (%rcx),%eax  
      add    0x18(%rsi),%eax  
      mov    %eax,(%rdx)  
      retq</pre>  
         </td>  
     </tr>  
   
     <tr><td><b><br>GCC 4.0.1 on i386:</b></td>  
     <tr>  
         <td valign="top">  
 <pre>mips_instr_addiu:  
      mov    0x8(%esp),%eax  
      mov    0x8(%eax),%ecx  
      mov    0x4(%eax),%edx  
      mov    0xc(%eax),%eax  
      add    (%edx),%eax  
      mov    %eax,(%ecx)  
      cltd  
      mov    %edx,0x4(%ecx)  
      ret</pre>  
         </td>  
         <td></td>  
         <td valign="top">  
 <pre>mips32_instr_addiu:  
      mov    0x8(%esp),%eax  
      mov    0x8(%eax),%ecx  
      mov    0x4(%eax),%edx  
      mov    0xc(%eax),%eax  
      add    (%edx),%eax  
      mov    %eax,(%ecx)  
      ret</pre>  
         </td>  
     </tr>  
 </table></center>  
   
 <p>On 64-bit hosts, there is not much difference, but on 32-bit hosts (and  
 to some extent on AMD64), the difference is enough to make it worthwhile.  
   
   
 <p><b>Performance:</b>  
   
 <p>The performance of using this kind of runnable IR is obviously lower  
 than what can be achieved by emulators using native code generation, but  
 can be significantly higher than using a naive fetch-decode-execute  
 interpretation loop. In my opinion, using a runnable IR is an interesting  
 compromise.  
   
 <p>The overhead per emulated instruction is usually around or below  
 approximately 10 host instructions. This is very much dependent on your  
 host architecture and what compiler and compiler switches you are using.  
 Added to this instruction count is (of course) also the C code used to  
 implement each specific instruction.  
   
 <p><b>Instruction Combinations:</b>  
   
 <p>Short, common instruction sequences can sometimes be replaced by a  
 "compound" instruction. An example could be a compare instruction followed  
 by a conditional branch instruction. The advantages of instruction  
 combinations are that  
 <ul>  
   <li>the amortized overhead per instruction is slightly reduced, and  
   <p>  
   <li>the host's compiler can make a good job at optimizing the common  
         instruction sequence.  
 </ul>  
   
 <p>The special cases where instruction combinations give the most gain  
 are in the cores of string/memory manipulation functions such as  
 <tt>memset()</tt> or <tt>strlen()</tt>. The core loop can then (at least  
 to some extent) be replaced by a native call to the equivalent function.  
   
 <p>The implementations of compound instructions still keep track of the  
 number of executed instructions, etc. When single-stepping, these  
 translations are invalidated, and replaced by normal instruction calls  
 (one per emulated instruction).  
   
 <p><b>Native Code Back-ends: (not in this release)</b>  
   
 <p>In theory, it will be possible to implement native code generation  
 (similar to what is used in high-performance emulators such as QEMU),  
 as long as that generated code abides to the C ABI on the host, but  
 for now I wanted to make sure that GXemul works without such native  
 code back-ends. For this reason, since release 0.4.0, GXemul is  
 completely free of native code back-ends.  
   
   
   
   
298    
299    
300  <p><br>  <p><br>
# Line 495  are emulated well enough to run at least Line 354  are emulated well enough to run at least
354      <li><b>Acer Pica-61</b> (<a href="guestoses.html#netbsdarcinstall">NetBSD/arc</a>)      <li><b>Acer Pica-61</b> (<a href="guestoses.html#netbsdarcinstall">NetBSD/arc</a>)
355      <li><b>NEC MobilePro 770, 780, 800, 880</b> (<a href="guestoses.html#netbsdhpcmipsinstall">NetBSD/hpcmips</a>)      <li><b>NEC MobilePro 770, 780, 800, 880</b> (<a href="guestoses.html#netbsdhpcmipsinstall">NetBSD/hpcmips</a>)
356      <li><b>Cobalt</b> (<a href="guestoses.html#netbsdcobaltinstall">NetBSD/cobalt</a>)      <li><b>Cobalt</b> (<a href="guestoses.html#netbsdcobaltinstall">NetBSD/cobalt</a>)
357      <li><b>Malta</b> (<a href="guestoses.html#netbsdevbmipsinstall">NetBSD/evbmips</a>)      <li><b>Malta</b> (<a href="guestoses.html#netbsdevbmipsinstall">NetBSD/evbmips</a>, Linux/Malta <font color="#0000e0">(<super>*1</super>)</font>)
358      <li><b>Algorithmics P5064</b> (<a href="guestoses.html#netbsdalgorinstall">NetBSD/algor</a>)      <li><b>Algorithmics P5064</b> (<a href="guestoses.html#netbsdalgorinstall">NetBSD/algor</a>)
359      <li><b>SGI O2 (aka IP32)</b> <font color="#0000e0">(<super>*1</super>)</font>      <li><b>SGI O2 (aka IP32)</b> <font color="#0000e0">(<super>*2</super>)</font>
360          (<a href="guestoses.html#netbsdsgimips">NetBSD/sgi</a>)          (<a href="guestoses.html#netbsdsgimips">NetBSD/sgi</a>)
361    </ul>    </ul>
362    <p>    <p>
363    <li><b><u>PowerPC</u></b>    <li><b><u>PowerPC</u></b>
364    <ul>    <ul>
365      <li><b>IBM 6050/6070 (PReP, PowerPC Reference Platform)</b> (<a href="guestoses.html#netbsdprepinstall">NetBSD/prep</a>)      <li><b>IBM 6050/6070 (PReP, PowerPC Reference Platform)</b> (<a href="guestoses.html#netbsdprepinstall">NetBSD/prep</a>)
366        <li><b>MacPPC (generic "G4" Macintosh)</b> (<a href="guestoses.html#netbsdmacppcinstall">NetBSD/macppc</a>)
367        <li><b>Artesyn PM/PPC</b> <font color="#0000e0">(<super>*2</super>)</font>
368            (<a href="guestoses.html#netbsdpmppc">NetBSD/pmppc</a>)
369    </ul>    </ul>
370    <p>    <p>
371    <li><b><u>SuperH</u></b>    <li><b><u>SuperH</u></b>
372    <ul>    <ul>
373      <li><b>Sega Dreamcast</b>      <li><b>Sega Dreamcast</b> (<a href="dreamcast.html#netbsd_generic_md">NetBSD/dreamcast</a>, <a href="dreamcast.html#linux_live_cd">Linux/dreamcast</a>)
374          <font color="#0000e0">(<super>*2</super>)</font>      <li><b>Landisk I-O DATA USL-5P</b> (<a href="guestoses.html#openbsdlandiskinstall">OpenBSD/landisk</a>)
         (<a href="guestoses.html#netbsddreamcast">NetBSD/dreamcast</a>)  
375    </ul>    </ul>
376  </ul>  </ul>
377    
378  <p>  <p>
379  <small><font color="#0000e0">(<super>*1</super>)</font> =  <small><font color="#0000e0">(<super>*1</super>)</font> =
380  Enough for root-on-nfs, but not for disk boot.</small>  Linux/Malta may be run as a guest OS, however I have not yet found any stable
381    URL to pre-compiled Linux/Malta kernels. Thus, Linux/Malta emulation is not
382    tested for every release of the emulator; sometimes it works, sometimes
383    it doesn't.</small>
384    
385  <br><small><font color="#0000e0">(<super>*2</super>)</font> =  <br><small><font color="#0000e0">(<super>*2</super>)</font> =
386  Only enough to reach ramdisk userland; no root-on-nfs yet.</small>  The emulation is enough for root-on-nfs, but no disk controller (SCSI nor
387    IDE) is emulated yet for this machine type.</small>
388    
389    <p>Note that of all of the machines above, none of them is emulated to
390    100%. The most complete emulation mode is probably the DECstation
391    5000/200. Things that will most likely <b>not</b> work include running
392    raw PROM images for most machines, SGI IRIX, MacOS X or Darwin, Windows
393    NT, or Dreamcast games.
394    
395  <p>There is code in GXemul for emulation of many other machine types; the  <p>There is code in GXemul for emulation of several other machine types; the
396  degree to which these work range from almost being able to run a complete  degree to which these work range from almost being able to run a complete
397  OS, to almost completely unsupported (perhaps just enough support to  OS, to almost completely unsupported, perhaps just enough support to
398  output a few boot messages via serial console).  output a few boot messages via serial console. (See the end of
399    <a href="guestoses.html#generalnotes">this section</a> on the Guest OSes
400    page for some examples, but remember that these do not necessarily work.)
401    
402  <p>In addition to emulating real machines, there is also a "test-machine".  <p>In addition to emulating real machines, there is also a "test-machine".
403  A test-machine consists of one or more CPUs and a few experimental devices  A test-machine consists of one or more CPUs and a few experimental devices
# Line 536  such as: Line 410  such as:
410    <li>a very simple linear framebuffer device (for graphics output)    <li>a very simple linear framebuffer device (for graphics output)
411    <li>a simple disk controller    <li>a simple disk controller
412    <li>a simple ethernet controller    <li>a simple ethernet controller
413      <li>a simple interrupt controller
414    <li>a real-time clock device    <li>a real-time clock device
415  </ul>  </ul>
416    

Legend:
Removed from v.32  
changed lines
  Added in v.44

  ViewVC Help
Powered by ViewVC 1.1.26