/[gxemul]/trunk/TODO
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/TODO

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

revision 14 by dpavlin, Mon Oct 8 16:18:51 2007 UTC revision 34 by dpavlin, Mon Oct 8 16:21:17 2007 UTC
# Line 1  Line 1 
1  $Id: TODO,v 1.173 2005/09/17 17:14:25 debug Exp $  $Id: TODO,v 1.453 2007/02/19 01:34:42 debug Exp $
2    
3  ===============================================================================  -------------------------------------------------------------------------------
4    
5  High priority stuff:  Fix after the 0.4.4 release:
6            Fix the PowerPC DECR interrupt speed!
7    
8    -------------------------------------------------------------------------------
9    
10  Old MIPS bintrans:  Possible (relatively large) work packages to concentrate on in the future:
11    
12          x)  call/return address cache?    x)  SMP:
13            Get SMP working again. It is pretty much broken since I started
14            the conversion from the old bintrans system to the new dyntrans system.
15            Add better Test machine demos for SMP in the demos directory.
16    
17          x)  Turn the MIPS cpu family stuff into dyntrans.    x)  Network:
18            Redesign of the networking subsystem, at least the NAT translation
19            part. The current way of allowing raw ethernet frames to be
20            transfered to/from the emulator via UDP should probably be extended
21            to allow the frames to be transmitted other ways as well.
22            Also adding support for connecting ttys (either to xterms, or to
23            pipes/sockets etc, or even to PPP->NAT or SLIP->NAT :-).
24    
25      x)  PCI:
26            Pretty much everything related to runtime configuration, device
27            slots, interrupts, whatever. The current code is very hardcoded
28            and ugly.
29    
30  Dyntrans:    x)  Debugging:
31            Think more about SMP debugging, etc. Right now, the
32          x)  Lots of stuff: see src/cpus/README_DYNTRANS          debugger is a mess. Also, a better connection to GDB would be
33            very nice to have.
34    
35      x)  Userland emulation:
36            Primary goals would be NetBSD and Linux syscall emulation.
37    
38  Userland emulation:  And of course, there are _LOTS_ of minor TODOs spread out throughout
39    the source code, which must be fixed sooner or later.
40    
41          x)  Lots of stuff.  -------------------------------------------------------------------------------
42    
43          x)  Dynamic linking? Hm.  Some other things, in random order, that I'd like to fix: (Some items in
44    this list are probably out-to-date by now.)
45    
46  ===============================================================================  Dyntrans:
47            x)  Instruction combination collisions? How to avoid easily...
48            x)  Think about how to do both SHmedia and SHcompact in a reasonable
49                way! (Or AMD64 long/protected/real, for that matter.)
50            x)  68K emulation; think about how to do variable instruction
51                lengths across page boundaries.
52            x)  Dyntrans with valgrind-inspired memory checker. (In memory_rw,
53                it would be reasonably simple to add; in each individual fast
54                load/store routine = a lot more work, and it would become
55                kludgy very fast.)
56            x)  Dyntrans with SMP... lots of work to be done here.
57            x)  Dyntrans with cache emulation... lots of work here as well.
58            o)  dev_mp doesn't work well with dyntrans yet
59            o)  In general, IPIs, CAS, LL/SC etc must be made to work with dyntrans
60            x)  Redesign/rethink the delay slot mechanism used for e.g. MIPS,
61                    so that it caches a translation (that is, an instruction
62                    word and the instr_call it was translated to the last
63                    time), so that it doesn't need to do slow
64                    to_be_translated for each end of page?
65            x)  Program Counter statistics:
66                    Per machine? What about SMP? All data to the same file?
67                    A debugger command should be possible to use to enable/
68                    disable statistics gathering.
69                    Configuration file option!
70            x)  Breakpoints:
71                    o) Physical vs virtual addresses!
72                    o) 32-bit vs 64-bit sign extension for MIPS, and others?
73            x)  INVALIDATION should cause translations in _all_ cpus to be
74                invalidated, e.g. on a write to a write-protected page
75                (containing code)
76            x)  16-bit encodings? (MIPS16, ARM Thumb, 32-bit SH on SH64)
77            x)  Lots of other stuff: see src/cpus/README_DYNTRANS
78            x)  true recompilation backend? think carefully about this.
79                    o)  abstract syntax for emitting opcopdes
80                    o)  convert into native code only after an entire
81                            block has been translated? probably best.
82                    o)  x86/amd64 code generator can be very similar... perhaps
83                    o)  branches to already translated code blocks can
84                            link the blocks together
85                    o)  load/store are the most important.
86    
87    Simple Valgrind-like checks?
88            o)  Mark every address with bits which tell whether or not the address
89                has been written to.
90            o)  What should happen when programs are loaded?  Text/data, bss (zero
91                filled). But stack space and heap is uninitialized.
92            o)  Uninitialized local variables:
93                    A load from a place on the stack which has not previously
94                    been stored to => warning. Increasing the stack pointer using
95                    any available means should reset the memory to uninitialized.
96            o)  If calls to malloc() and free() can be intercepted:
97                    o)  Access to a memory area after free() => warning.
98                    o)  Memory returned by malloc() is marked as not-initialized.
99                    o)  Non-passive, but good to have: Change the argument
100                        given to malloc, to return a slightly larger memory
101                        area, i.e.  margin_before + size + margin_after,
102                        and return the pointer  + margin_before.
103                        Any access to the margin_before or _after space results
104                        in warnings. (free() must be modified to free the
105                        actually allocated address.)
106    
107    MIPS:
108            o)  Nicer MIPS status bits in register dumps.
109            o)  Alignment exceptions.
110            o)  Floating point exception correctness.
111            o)  Fix this? Triggered by NetBSD/sgimips? Hm:
112                    to_be_translated(): TODO: unimplemented instruction:
113                    000000000065102c: 00200800 (d)  rot_00  at,zr,0
114            o)  Some more work on opcodes.
115                    x) MIPS64 revision 2.
116                            o)  Find out which actual CPUs implement the rev2 ISA!
117                            o)  DROTR32 and similar MIPS64 rev 2 instructions,
118                                which have a rotation bit which differs from
119                                previous ISAs.
120                            o)  EI and DI instructions for MIPS64/32 rev 2.
121                                NOTE: These are _NOT_ the same as for R5900!
122                    x) _MAYBE_ TX79 and R5900 actually differ in their
123                       opcodes? Check this carefully!
124            o)  Dyntrans: Count register updates are probably not 100% correct yet.
125            o)  Refactor code for performance and readability/maintainability.
126            o)  (Re)implement 128-bit loads/stores for R5900.
127            o)  R4000 and others:
128                    x)  watchhi/watchlo exceptions, and other exception
129                        handling details
130            o)  R10000 and others:  (R12000, R14000 ?)
131                    x)  The code before the line
132                            /*  reg[COP0_PAGEMASK] = cpu->cd.mips.coproc[0]->tlbs[0].mask & PAGEMASK_MASK;  */
133                        in cpu_mips.c is not correct for R10000 according to
134                        Lemote's Godson patches for GXemul. TODO: Go through all
135                        register definitions according to http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi/hdwr/bks/SGI_Developer/books/R10K_UM/sgi_html/t5.Ver.2.0.book_263.html#HEADING334
136                        and make sure everything works with R10000.
137                        Then test with OpenBSD/sgi?
138                    x)  memory space, exceptions, ...
139                    x)  use cop0 framemask for tlb lookups
140                        (http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi/hdwr/bks/SGI_Developer/books/R10K_UM/sgi_html/t5.Ver.2.0.book_284.html)
141    
142    SuperH:
143            x)  SH4 interrupt controller:
144                    x)  Implement correct priorities of interrupts
145            x)  SH4 DMA (0xffa00000)
146            x)  SH4 UBC (0xff200000)
147            x)  Store queues can copy 32 bytes at a time, there's no need to
148                copy individual 32-bit words. (Performance improvement.)
149            x)  SH4 BSC (Bus State Controller)
150            x)  SH4 RTC: Read the host's clock.
151            x)  SH4 SCIF: Serial _interrupts_
152            x)  Instruction tracing should include symbols for branch targets,
153                and so on, to make the output more human readable.
154            x)  NetBSD/evbsh3, dreamcast, mmeye, hpcsh! Linux?
155            x)  Replace pc-relative loads with immediate load, if within the
156                same page. (Similar to the same optimization for ARM.)
157            x)  Floating point speed!
158            x)  Floating point exception correctness.
159            x)  Think carefully about how to implement SH5/SH64 (for evbsh5).
160    
161    Dreamcast:
162            x)  G2 DMA
163            x)  LAN adapter (dev_mb8696x.c).  NetBSD root-on-nfs.
164            x)  PVR:  Lots of stuff. See dev_pvr.c.
165            x)  GDROM
166            x)  Modem
167            x)  PCI bridge/bus?
168            x)  Maple bus:
169                    x)  Correct controller input
170                    x)  Mouse input
171            x)  Software emulation of BIOS calls:
172                    x)  GD-ROM emulation: Use the GDROM device.
173                    x)  Use the VGA font as a fake ROM font. (Better than
174                        nothing.)
175            x)  Linux/dreamcast? (The gentoo kernel currently crashes.)
176            x)  Make as many as possible of the KOS examples run!
177            x)  More homebrew demos/games.
178            x)  SPU: Sound emulation (ARM cpu).
179            x)  VME processor emulation? "(Sanyo LC8670 "Potato")" according to
180                Wikipedia, LC86K87 according to Comstedt's page. See
181                http://www.maushammer.com/vmu.html for a good description of
182                the differences between LC86104C and the one used in the VME.
183    
184    Transputer:
185            x)  Implement support for Helios binaries.
186            x)  Stack and register contents at startup?
187            x)  Figure out how to boot an entire Helios distribution.
188            x)  Implement all instructions. :)
189    
190    RCA1802/RCA1805, CHIP8:
191            x)  CHIP8 -> RCA180x conversion
192                    x)  Think about how to do dual-mode, variable-instr-length
193                        ISAs, and switch between modes.
194                    x)  1805 "extended" opcode -> trigger CHIP8 emulation?
195                            That is, all calls 0NNN could point to 0x68 opcodes,
196                            which, if running on a 1802 in CHIP8-emulation-mode,
197                            would be manually interpreted.
198                    x)  Better solution:
199                            CHIP8 calls to 00xx => handle at high level,
200                                  calls to 0xxx in general = call 180X machine code
201                                    (0000 = reboot?)
202            x)  1802 info: http://www.nyx.net/~lturner/public_html/Cosmac.html
203                and:  http://www.elf-emulation.com/1802.html
204            x)  1805 extended opcodes: Implement at least disassembly support!
205            x)  Keyboard input.
206            x)  Sound (beep only).
207            x)  Slow-down to correct speed? Wikipedia: "it was usually operated
208                at 3.58 MHz/2 to suit the requirements of the 1861 chip which
209                gave a speed of a little over 100,000 instructions per second"
210                (Note that _CHIP8_ emulation would then be even slower.)
211            x)  SCHIP48 (Super) emulation:
212                    Some more opcodes, 128x64 framebuffer, larger
213                    sprites and fonts.
214    
215    Alpha:
216            x)  OSF1 PALcode, Virtual memory support.
217            x)  PALcode replacement! PAL1E etc opcodes...?
218            x)  Interrupt/exception/trap handling.
219            x)  Floating point exception correctness.
220            x)  More work on bootup memory and register contents.
221            x)  More Alpha machine types, so it could work with
222                OpenBSD, FreeBSD, and Linux too?
223    
224    SPARC:
225            o)  Implement Adress space identifiers; load/stores etc.
226            o)  Save/restore register windows etc! Both v9 and pre-v9!
227            o)  Finish the subcc and addcc flag computation code.
228            o)  Add more registers (floating point, control regs etc)
229            o)  Exception/trap handling.
230            o)  Disassemly of some more instructions?
231            o)  Are sll etc 32-bit sign-extending or zero-extending?
232            o)  Finish the GDB register stuff.
233            x)  Floating point exception correctness.
234            o)  SPARC v8, v7 etc?
235    
236    Debugger:
237            o)  How does SMP debugging work? Does it simply use "threads"?
238                    What if the guest OS (running on an emulated SMP machine)
239                    has a usertask running, with userland threads?
240            o)  Try to make the debugger more modular and, if possible, reentrant!
241            o)  Remove the emul command? (But show network info if showing
242                    machines?)
243            o)  Evaluate expressions within []? That would allow stuff like
244                    cpu[x] where x is an expression.
245            o)  Settings:
246                    x)  Special handlers for Write!
247                            +)  MIPS coproc regs
248                            +)  Alpha/MIPS/SPARC zero registers
249                            +)  x86 64/32/16-bit registers
250                    x)  Value formatter for resulting output.
251            o)  see src/debugger.c for more
252    
253    POWER/PowerPC:
254            x)  Fix DECR timer speed, so it matches the host.
255            x)  NetBSD/prep 3.x triggers a possible bug in the emulator:
256                <wdc_exec_command(0xd005e514,0xd60cdd30,0,8,..)>
257                  <ata_get_xfer(0,0xd60cdd30,0,8,..)>
258                    <0x26c550(&ata_xfer_pool,2,0,8,..)>
259                    <0x35c71c(0x3f27000,0,52,8,..)>
260                  <ata_exec_xfer(0xd005e4c8,0x3f27000,0,13,..)>
261                    <atastart(0xd005e4c8,0x3f27000,0,13,..)>
262                      <__wdccommand_start(0xd005e4c8,0x3f27000,0,13,..)>
263                        <bsw1(&prep_isa_io_space_tag,0x800001f6,0,176,..)>
264                    [ wdc: write to SDH: 0xb0 (sectorsize 2, lba=1, drive 1, head 0) ]
265                        <wdcwait(0xd005e4c8,72,64,0xbb8,..)>
266                          <0x198120(0xd005e4c8,72,64,0xbb8,..)>
267                            <bsr1(&prep_isa_io_space_tag,0,0,0xbb8,..)>
268                            <delay(100,0,0,0xbb8,..)>
269                Note: <bsr1(&prep_isa_io_space_tag,0,0,0xbb8,..)>
270            x)  PPC optimizations; instr combs
271            x)  64-bit stuff: either Linux on G5, or perhaps some hobbyist
272                    version of AIX? (if there exists such a thing)
273            x)  macppc: adb controller; keyboard (for framebuffer mode)
274            x)  make OpenBSD/macppc work (PCI controller stuff)
275            x)  Floating point exception correctness.
276            x)  Alignment exceptions.
277    
278    PReP:
279            Clock time! ("Bad battery blah blah")
280    
281    Algor:
282            o)  Other models than the P5064?
283            o)  PCI interrupts... needed for stuff like the tlp NIC?
284    
285    BeBox:
286            o)  Interrupts. There seems to be a problem with WDC interrupts
287                "after a short while", although a few interrupts get through?
288            o)  Perhaps find a copy of BeOS and try it?
289    
290    HPCmips:
291            x)  Mouse/pad support! :)
292            x)  A NIC? (As a PCMCIA device?)
293    
294    AVR:
295            o)  Everything.
296    
297    ARM:
298            o)  See netwinder_reset() in NetBSD; the current "an internal error
299                occured" message after reboot/halt is too ugly.
300            o)  ARM "wait"-like instruction?
301            o)  try to get netbsd/evbarm 3.x or 4.x running (iq80321)
302            o)  make the xscale counter registers (ccnt) work
303            o)  make the ata controller usable for FreeBSD!
304            o)  Zaurus emulation, for e.g. OpenBSD/zaurus
305            o)  Debian/cats crashes because of unimplemented coproc stuff.
306                fix this?
307    
308    Test machines:
309            o)  dev_fb block fill and copy
310            o)  dev_fb draw characters (from the built-in font)?
311            o)  dev_fb input device? mouse pointer coordinates and buttons
312                    (allow changes in these to cause interrupts as well?)
313            o)  Redefine the halt() function so that it stops "sometimes
314                soon", i.e. usage in demo code should be:
315                    for (;;) {
316                            halt();
317                    }
318    
319    Better CD Image file support:
320            x)  Support CD formats that contain more than 1 track, e.g.
321                CDI files (?). These can then contain a mixture of e.g. sound
322                and data tracks, and booting from an ISO filesystem path
323                would boot from [by default] the first data track.
324                (This would make sense for e.g. Dreamcast CD images, or
325                possibly other live-CD formats.)
326    
327    Networking:
328            x)  Fix performance problems caused by only allowing a
329                single TCP packet to be unacked.
330            x)  Don't hardcode offsets into packets!
331            x)  Test with lower than 100 max tcp/udp connections,
332                to make sure that reuse works!
333            x)  Make OpenBSD work better as a guest OS!
334            x)  DHCP? Debian doesn't actually send DHCP packets, even
335                    though it claims to? So it is hard to test.
336            x)  Multiple networks per emulation, and let different
337                NICs in machines connect to different networks.
338            x)  Support VDE (vde.sf.net)? Easiest/cleanest (before a
339                redesign of the network framework has been done) is
340                probably to connect it using the current (udp) solution.
341            x)  Allow SLIP connections, possibly PPP, in addition to
342                ethernet?
343    
344    Cache simulation:
345            o)  Command line flags for:
346                    o)  CPU endianness?
347                    o)  Cache sizes? (multiple levels)
348            o)  Separate from the CPU concept, so that multi-core CPUs sharing
349                e.g. a L2 cache can be simulated (?)
350            o)  Instruction cache emulation is easiest (if separate from the
351                data cache); similar hack as the S;I; hack in cpu_dyntrans.c.
352                NOTE: if the architecture has a delay slot, then an instruction
353                slot can actually be executed as 2 instructions.
354            o)  Data cache emulation = harder; each arch's load/store routines
355                must include support? running one instruction at a time and
356                having a cpu-dependant lookup function for each instruction
357                is another option (easier to implement, but very very slow).
358    
359    Documentation:
360            x)  Note about sandboxing/security:
361                    Not all emulated instructions fail in the way they would
362                    do on real hardware (e.g. a userspace program writing to
363                    a system register might work in GXemul, but it would
364                    fail on real hardware).  Sandbox = contain from the
365                    host OS. But the emulated programs will run "less
366                    securely".
367            x)  Try NetBSD/arc 4.x! (It seems to work with disk images!)
368            x)  NetBSD/pmax 4 install instructions: xterm instead of vt100!
369            x)  BETTER DEVICE EXAMPLES!
370                    o)  Move away from technical.html to somewhere new.
371                    o)  DEVICE_TICK
372                    o)  Implement example devices using interrupts, dyntrans
373                        memory access, etc.?
374            x)  Document the dyntrans core?
375            x)  Rewrite the section about experimental devices, after the
376                framebuffer acceleration has been implemented, and demos
377                written. (Symbolic names instead of numbers; example
378                use cases, etc. Mention demo files that use the various
379                features?)
380            x)  "a very simple linear framebuffer device (for graphics output)"
381                under "which machines does gxemul emulate" ==> better
382                description?
383            x)  Better description on how to set up a cross compiler?
384                Example for MIPS64.
385            o)  Automagic documentation generation?
386                    x)  machines, cpus, devices.
387                    x)  REMEMBER that several machines/devices can be in
388                            the same source file!
389            o)  Try to rewrite the install instructions for those machines
390                that use 3MAX into using CATS or hpcmips? (To remove the need
391                to use a raw ffs partition, using up all of the disk image.)
392    
393    More generic out_of_memory error reporting, and check everywhere!
394            Causes: OpenBSD has low default limits for normal users.
395                    Host is 32-bit? (32-bit hosts are limited to 4 GB or less
396                    of userspace memory.)
397                    You are actually low on RAM. (As trivial as this might sound,
398                    Unix systems usually allow processes to allocate virtual
399                    memory beyond the amount of RAM in the machine.)
400    
401    The Device subsystem:
402            x)  allow devices to be moved and/or changed in size (down to a
403                minimum size, etc, or up to a max size); if there is a collision,
404                return false. It is up to the caller to handle this situation!
405            x)  NOTE: Translations must be invalidated, both for
406                registering new devices, and for moving existing ones.
407                cpu->invalidate translation caches, for all CPUs that
408                are connected to a specific memory.
409            x)  keep track of interrupts and busses? actually, allowing any device
410                to be a bus might be a nice idea.
411            x)  turn interrupt controllers into devices? :-)
412            x)  refactor various clocks/nvram/cmos into one device?
413    
414    PCI:
415            x)  last write was ffffffff ==> fix this, it should be used
416                together with a mask to get the correct bits. also, not ALL
417                bits are size bits! (lowest 4 vs lowest 2?)
418            x)  add support for address fixups
419            x)  generalize the interrupt routing stuff (lines etc)
420    
421    Clocks and timers:
422            x)  DON'T HARDCODE 100 HZ IN cpu_mips_coproc.c!
423            x)  Test the 8253? Right now it doesn't seem to be used?
424            x)  NetWinder timeofday is incorrect!
425            x)  Cobalt TOD is incorrect!
426            x)  Go through all other machines, one by one, and fix them.
427    
428    Config file parser:
429            o)  Rewrite it from scratch!
430            o)  Usage of any expression available through the debugger
431            o)  Allow interrupt controllers to be added! and interrupts
432                to be used in more ways than before
433            o)  Support for running debugger commands (like the -c
434                command line option)
435    
436    Floating point layer:
437            o)  make it common enough to be used by _all_ emulation modes
438            o)  implement correct error/exception handling and rounding modes
439            o)  implement more helper functions (i.e. add, sub, mul...)
440            o)  non-IEEE modes (i.e. x86)?
441    
442  Lower priority, but still important:  Userland emulation:
443            x)  Lots of stuff; freebsd and netbsd (and linux?) syscalls.
444            x)  Dynamic linking? Hm.
445    
446          Redesign the entire "mainbus" concept:  Sound:
447                  o)  Easily configurable interrupt routing in SMP systems.          x)  generic sound framework
448                  o)  Specific clock/bus speeds, cpu speeds etc.          x)  add one or more sound cards as devices; add a testmachine
449                  o)  Synchronization over network?              sound card first?
450            x)  Dreamcast sound? Generic PCI sound cards?
451          Caches / memory hierarchies: (this is mostly MIPS-specific)  
452                  o)  MIPS coproc.c: bits in config registers should reflect  ASC SCSI controller:
453                      correct cache sizes for _all_ CPU types. (currently only          x)  NetBSD/arc 2.0 uses the ASC controller in a way which GXemul
454                      implemented for R4000, R1x000, and a few others)              cannot yet handle. (NetBSD 1.6.2 works ok.) (Possibly a problem
455                  o)  src/memory*.c: Implement correct cache emulation for              in NetBSD itself, http://mail-index.netbsd.org/source-changes/
456                      all CPU types. (currently only R2000/R3000 is implemented)              2005/11/06/0024.html suggests that.)
457                      (per CPU, multiple levels should be possible,              NetBSD 4.x seems to work? :)
458                      associativity etc!)  
459                  o)  R2000/R3000 isn't _100%_ correct, just almost correct :)  Caches / memory hierarchies: (this is mostly MIPS-specific)
460                  o)  Move the -S (fill mem with random) functionality into the          o)  src/memory*.c: Implement correct cache emulation for
461                      memory.c subsystem, not machine.c or wherever it is now              all CPU types. (currently only R2000/R3000 is implemented)
462                  o)  ECC stuff, simulation of memory errors?  (Machine dependant)              (per CPU, multiple levels should be possible, associativity etc!)
463                  o)  More than 4GB of emulated RAM, when run on a 32-bit host?          o)  R2000/R3000 isn't _100%_ correct, just almost correct :)
464                      (using manual swap-out of blocks to disk, ugly)          o)  Move the -S (fill mem with random) functionality into the
465                  o)  A global command line option should be used to turn              memory.c subsystem, not machine.c or wherever it is now
466                      cache emulation on or off. When off, caches should be          o)  ECC stuff, simulation of memory errors?  (Machine dependent)
467                      faked like they are right now. When on, caches and          o)  More than 4GB of emulated RAM, when run on a 32-bit host?
468                      memory latencies should be emulated as correctly as              (using manual swap-out of blocks to disk, ugly)
469                      possible.          o)  A global command line option should be used to turn
470                cache emulation on or off. When off, caches should be
471          Network layer:              faked like they are right now. When on, caches and
472                  o)  Multiple networks per emulation, and let different              memory latencies should be emulated as correctly as
473                      NICs in machines connect to different networks.              possible.
474                  o)  many other issues: see src/net.c  
475    File/disk/symbol handling:
476          MIPS CPU emulation:          o)  Make sure that disks can be added/removed during runtime!
477                  o)  i386 bintrans backend: movn etc, slt[u] for              (Perhaps this needs a reasonably large re-write.)
478                          64-bit mode, 64-bit shifts etc          o)  Remove some of the complexity in file format guessing, for
479                  o)  Instructions:                  Ultrix kernels that are actually disk images?
480                          o)  All ISAs:          o)  Better handling of tape files      
481                                  o)  Floating point exception handling, and          o)  Read function argument count and types from binaries? (ELF?)
482                                          add more instructions.          o)  Better demangling of C++ names. Note: GNU's C++ differs from e.g.
483                                  o)  Finish the MIPS16 translator, and test it!              Microsoft's C++, so multiple schemes must be possible. See
484                                  o)  MIPS ISA I, II, III, IV              URL at top of src/symbol_demangle.c for more info.
485                                  o)  MIPS V (SIMD vector stuff?)  
486                                  o)  MDMX  (MIPS Digital Media Extension)  Userland ABI emulation:
487                                  o)  MIPS 3D          o)  see src/useremul.c
488                                  o)  MIPS MT (Multi-thread stuff) (What's this?)  
489                          o)  Warn about mis-used bit fields (ie bits that  Better framebuffer and X-windows functionality:
490                              should be all zeroes, warn about if they are not)!          o)  Generalize the update_x1y1x2y2 stuff to an extend-region()
491                              Both for coprocessor registers and for instruction              function...
492                              opcodes.          o)  -Yx sometimes causes crashes.
493                          o)  the special2 stuff is a mess right now          o)  Simple device access to framebuffer_blockcopyfill() etc,
494                          o)  warn and/or cause exceptions for unimplemented              and text output (using the built-in fonts), for dev_fb.
495                              instructions (depending on CPU type)          o)  CLEAN UP the ugly event code
496                  o)  R2000/R3000:          o)  Mouse clicks can be "missed" in the current system; this is
497                          x)  R3000 "tri-byte stores". (What's this?)              not good. They should be put on a stack of some kind.
498                  o)  R4000 and others:          o)  More 2D and 3D framebuffer acceleration.
499                          x)  watchhi/watchlo exceptions, and other exception          o)  Non-resizable windows?  Or choose scaledown depending
500                              handling details                  on size (and center the image, with a black border).
501                  o)  R10000 and others:  (R12000, R14000 ?)          o)  Different scaledown on different windows?
502                          x)  memory space, exceptions, ...          o)  Non-integral scale-up? (E.g. 640x480 -> 1024x768)
503                          x)  use cop0 framemask for tlb lookups          o)  Switch scaledown during runtime? (Ala CTRL-ALT-plus/minus)
504                              (http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi/hdwr/bks/SGI_Developer/books/R10K_UM/sgi_html/t5.Ver.2.0.book_284.html)          o)  Bug reported by Elijah Rutschman on MacOS with weird
505                  o)  Implement load delays?  Warnings on interlocks.              keys (F5 = cursor down?).
506                  o)  Implement all coprocessor 0 bits / functions.          o)  Keyboard and mouse events:
507                          x)  coproc 0 selectors! (R4000 ?)                  x)  Do this for more machines than just DECstation
508                  o)  R4300 (nintendo64, no mmu?), R5900 (playstation2, weird                  x)  more X11 cursor keycodes
509                          TLB/cache? 128-bit GPRs, new instructions),                  x)  Keys like CTRL, ALT, SHIFT do not get through
510                          4K (note: NOT R4000), 5K (note: NOT R5000),                      by themselves (these are necessary for example
511                          R6000 (ISA II), R8000                      to change the font of an xterm in X in the
512                  o)  Multi-cpu stuff:                      emulator)
513                          +)  Interrupt routing (ie devices vs mainbus, or          o)  Generalize the framebuffer stuff by moving _ALL_ X11
514                              connect each device to a fixed cpu)                  specific code to src/x11.c!
                         +)  SGI's NUMA architecture. Study  
                                 x)  Linux sources  
                                 x)  SGI's specs on NUMA address space  
                         +)  Ultrix?  NetBSD doesn't do SMP on MIPS yet :-(  
                         +)  Own experiments with ycx2.  
   
         File/disk handling:  
                 o)  Better handling of tape files  
   
         Debugger:  
                 o)  Read function argument count and types from binaries? (ELF?)  
                 o)  Demangle C++ names.  
                 o)  see src/debugger.c for more stuff  
   
         Userland ABI emulation:  
                 o)  see src/useremul.c  
   
         Terminal/console stuff:  
                 o)  allow emulated serial ports to be connected to the outside  
                     world in a more generic way, or even to other emulated  
                     machines(!)  
   
         Regression tests.  (Needs to be totally rewritten, the old framework  
                 was removed because it was useless.)  
   
         Save state of the whole emulated machine, to be able to load it back  
                 in later?  (Memory, all device's states, all registers and  
                 so on.  Like taking a snapshot. (SimOS seems to do this,  
                 according to its website.))  
   
         Better X-windows functionality:  
                 o)  CLEAN UP the ugly event code  
                 o)  Mouse clicks can be "missed" in the current system; this is  
                     not good. They should be put on a stack of some kind.  
                 o)  More 2D and 3D framebuffer acceleration.  
                 o)  Non-resizable windows?  Or choose scaledown depending  
                         on size (and center the image, with a black border).  
                 o)  Different scaledown on different windows?  
                 o)  Switch scaledown during runtime? (Ala CTRL-ALT-plus/minus)  
                 o)  Keyboard and mouse events:  
                         x)  Do this for more machines than just DECstation  
                         x)  more X11 cursor keycodes  
                         x)  Keys like CTRL, ALT, SHIFT do not get through  
                             by themselves (these are necessary for example  
                             to change the font of an xterm in X in the  
                             emulator)  
                 o)  Generalize the framebuffer stuff by moving _ALL_ X11  
                         specific code to src/x11.c!  
   
         Statistics:  (this could be interesting)  
                 o)  Save to file and show graphics. It should be possible to  
                     run gxemul after a simulation to just show the graphics,  
                     or convert to a .ppm or .tga or similar.  
                 o)  memory accesses (to measure cache efficiency and  
                         page coloring efficiency)  
                 o)  nr of simultaneous ASIDs in use in the TLB, for MIPS  
                 o)  percentage of time spent in different "states", such as  
                     running userland code, kernel code, or idling (for CPUs  
                     that have such an instruction, or whenever the PC is  
                     inside a specific idle-function (address range)).  
                     Possible additional state (for example on R3000): caches  
                     disabled.  
                 o)  position of read/write on (SCSI) disks  
515    

Legend:
Removed from v.14  
changed lines
  Added in v.34

  ViewVC Help
Powered by ViewVC 1.1.26