Re: some docs needed
like system for 286. For this I would need some doc on very accurate doc on programming i286 in pmode and some doc on MinixFS (ok, I know almost The Minix book covers the minixfs a bit. The 286 stuff I dont know good docs on - they all seem to be discontinued. The pII downloadable manuals are very patchy on 16bit protected mode
Re: A question
From what I understand, using the task struct to keep track of sleeping processes, limits the number of processes the kernel can handle. If you In a sense since wakeup is O(N) by number of processes processes, you can increase functionality. If the number of sleeping processes is more then a certain number, you can activate the pointer and the kernel can follow the pointer like in a linked list. So you don't really use a linked list like linux does, but you use an array and when it's full, you can point to another array. For ELKS it isnt worth it. For real Linux it would be (and in fact it does it all with lists)
Re: A question
various extended features (which few use) can then be easily added on a personal basis. I doubt that ELKS has ever run more than 15 processes, for instance. For reference the standard V7 builds were for about 30-60 processes (60 being a big box).
Re: Definitive tree
and the source is now stored under CVS at sourceforge: http://sourceforge.net/project/?group_id=3232 I'll grab the sourceforget copy and probably send you diffs. (I dont have the local bandwidth to fight cvs) Is this in some way related to your idea of moving the structure required from the kernel stack to the task structure? Yes Alan
Surgery On Linux 8086
We have far too much ifdef crap. We appear to have more build options than users. I've stripped out some of them in my tree (NOFS, SUID, CORE DUMP) and I'll clean up more as I go so we actually have one OS not one OS each. I've rewritten the wait queue code. We now do it sort of V7 style. You can wait on one thing only (except for select see later) current-waitpt is the object you are waiting on (a waitqueue is now a char but could be removed as a concept eventually). The kernel loops through each task (hell we only have 30 or so ;)) and wakes those with matching ptr If the pointer is to the select wait then we instead check if the object we are waiting hashed into 16 buckets lands in a marked bucket. If so we wake the task (and if the hashing is wrong it will sleep again). 16 may be too low but 32 or 64 should work nicely The kernel got smaller in the process and you no longer need a good computing head to understand kernel/sleepwake.c Alan
Re: Definitive tree
I've gotten pretty familiar with the linker, let me know if you need a hack. Otherwise, my memory says that we've got enough info in the current header to put the stack below the data, providing the linker will change the beginning data offset to the max stack size. We can already build binaries for this format. What we cant do is build ones you can chmem. I now have an ELKS that is a bit cleaner (not a lot), has my new wait queue code working and I've written but not tested the back end for the swapper. It needs someone strategy code and syscalls. Right now only the bios driver will get swapping right since I had to add req-rq_seg so I can swap stuff without going via buffer cache - also means I guess we can write directly from the L2 buffer cache. Alan
Todays hacks
[The full patch is 80K - who wants to check it in ?] --- elks/CHANGELOG Fri Mar 3 11:42:19 2000 +++ elks-ac/CHANGELOG Mon Jun 19 23:52:08 2000 @@ -6,6 +6,31 @@ Al -- +Mon Jun 19 29:39 GMT 2000 Alan Cox [EMAIL PROTECTED] + + * Abolished the suid config option + * Merged stuff to reduce the ifdef clutter a bit + * Removed the nonexistant ip socket stuff. Its confusing having + all this old nonentity crap in it + * Buffer cache and request queue now have segment data + * Implemented segment stuff in the bios driver + * Added the back end code (untested so far) for swapping + * Replaced the wait queues with a V7 like wakeup mechanism + with a bit of auditing we should be ready to page kernel stacks + of sleeping processes that will free a fair bit of the data + segment at the same time as upping the task limit + - still need to get stacks smaller than 1K/task. + * Made select work using a crude hash and the V7 like wakeups. May + need a bigger hash + * Removed CONFIG_NOFS - just too ugly right now + * key_asm.S was dos line endings - fixed + * Cleaned up random #if 0 stuff + * Reformatted xt_key.c since it had bad tab/space damage + * Fixed incorrect comment about irqs + * Killed bh-b_prev for good + * Killed inode hash for good + * Make off_t signed as required by Unix and Posix + Fri Mar 03 11:44 GMT 2000 Alistair Riddoch [EMAIL PROTECTED] * Final changes for 0.0.83
Re: A question
Could anyone explain me what is a V7 like wakeup mechanism? Old old unix systems took the address of the thing they wanted to wait on and placed it in the task structure. Since the number of processes is pretty low its easy for the CPU to walk the process table on a wakeup checking if the 'wakeup' for this process matches the value it is given to wake. Its low on memory usage, its simple and it works low end. Later Unixes apparently started hashing them as the process sets got bigger, and Linux uses linked lists of tasks waiting on an event - relatively memory expensive but very clean and scalable - a good tradeoff for Linux a bad one for ELKS
Re: Definitive tree
: I think I've figured how to : sort some of the stack handling stuff out and get some of our data space : back. You're not thinking of backtracing stack addresses, are you? No. Something much simpler. The idea being to get into a state where there is nothing on the kernel stack needed when a task is not in RUN state.. ie replacing the wait queue/select stuff with a V7 like setup. User space Im very tempted to rebuild the system with the stack at the base of the data segment, although that would prevent chmem working without relocation maps on load. It trades it for the ability to truely grow process space once you have swap Alan
Re: ELKS to do?
for(i=0; i6; ++i) ; nosound(); } which is way too long (5 seconds) for any 8086 I've ever used (or my Tandy's V-20). Is there something akin to bogomips that is tested by ELKS that can be used to set the loop to some processor speed dependent value? Use the bogomips value for the loop should be about right IMHO
Re: Market space for a 16-bit linux product?
After all, there exists MINIX and open-source 11Kb kernels for microcontrollers with TCP/IP stack and all... 11K with tcp/ip - I've not seen that. 11K core oh and its 30K for TCP minimum but we didnt tell you until you asked I have seen ;)
Re: palmtop OS
Anyone know if I can a get a UNIX-like OS on my PSION 5, does it require a flash card for extra storage space? (8meg...) Linux is running on the 5 but not 5MX. You want a flash card for it. You also want to think what your intended use is - the speed on those kind of devices is not going to lend itself to compiling for example. or, is there a palmtop I can invest in that is beter for UNIX?? I ended up with a small PC. The old IBM PC110 was the smallest but as its 486 era it outlived its usefulness. I now have a palmax which is a bit bigger but just about fits in a coat pocket. Others like the old Librettos
Re: Re[2]: palmtop OS
actually, I am intending to use it for C programming (on the move...) from CLI, cos its got a HUGE battery life and Im learning C. Common misconception. It is designed to operate on a very low power level. When you start needing high power levels its battery life is poor. Alan
Re: ELKS and TCP/IP
is out there and ported to a micro or two. Only does PPP though. It appears to be derived from KA9Q, BSD and Linux code. I think the site is http://www.ucos-ii.com/ KA9Q is $50 a copy of non education/non amateur radio users Alan
Re: elks
Then I am missing quite a bit of recognition of the early work in porting UNIX in the form of Minix by the group of Andy Tanenbaum. We still have the minix format around, but Andy was one of the first the throw open the full source code for Minix in his book: Operating Systems, Design Implementation, PH, long before Linus Torwalds made it into a full, viable system. And both Dave Braun and Steve Hosgood before him - and we keep finding more of these. Its a good demo that the net wasnt good enough to support such probjects (UZI btw will run on a CP/M Z80 box)
Re: Location of ELKS Archive?
Looking at the state of the project it is no longer obvious to me which way to proceed. It essentially runs pretty stably on all my test platforms, and I have reached the point where it is no longer obvious to me what to do next. Any ideas anyone? Call it 0.99 announce it and go on holiday is I believe Linus approach 8) Basically it works. Alan
Re: Location of ELKS Archive?
Does this mean ELKS has TCP/IP networking with PPP and/or SLIP? Nope. Thats a totally seperate project
Re: Is ELKS a good idea for teaching O.S.
dosemu is enough for Elks. I did not try yet but it must be light and fast. If someone want to run Elks on non x86, then she need Bochs Also there is alternative of VMware is under development with GPL... http://www.plex86.org/ (it was called FreeMWare). I am expecting this... Also usermode linux may be of interest once its a bit more stable Alan
Re: ELKS for ARM
I have started porting ELKS for ARM. Is is somebody working similar project? I believe there is a ucLinux ARM project for the 7500T. (ucLinux is full Linux without an MMU) Alan
Re: 8086/88 80286 ||| 80386 80486 Pentium ...
I have a 386 AND a 486 that I am unable to bring up on Linux because the current version requires more than 8 MB ram. The setup that I want requires No. The current Linux is fine in 4Mb. The distribution installers with all their GUI garbage frequently require more. If you are trying to build a distribution on a small box I'd suggest you borrow a Debian CD from someone. Right now its the only major dist I know that will install sensibly in 4/8Mb
Re: 8086/88 80286 ||| 80386 80486 Pentium ...
Do any one had a linux ported to Hitachi processor.can elks can be used for embedded systems is there any one who is intrested for a linux kernel development. There is a standard linux port for SH3 Alan
Re: Interesting
1) Is ELKS qualified for Safety applications (Eg: Plant Temperature Control system, and is the Kernel development controlled by some body of members) Right now ELKS is a 'hey it sort of works' piece of fun 2) I have a 8088 based Industrial PC\XT board and is it possible to run Linux on it. Maybe 4) Is this ELKS formally distributed like RedHat Linux, SuSe Linux as a product or is it a free product. Its just a couple of disks of free toys Electronics Instrumentation Division Indira Gandhi Centre for Atomic Research, Kalpakkam. Please dont run any atomic power stations on it just yet 8)
Re: KA9Q
that might be useable as a user-mode ELKS implmentation of IP, UDP and TCP. And it supports alot of different cards Not directly tho as well as serial. KA9Q net was the earlier package, it ran on CP/M once so may fit
Re: May be mistake?
if (irq 8) {
cache_21 |= 1 irq;
outb(0x21,cache_21); --- outb(cache_21,0x21);
} else {
cache_A1 |= 1 (irq-8);
outb(0xA1,cache_A1); --- outb(cache_A1,0xA1);
Linux outb() macros are data, port
Re: self-compile bcc?
I fully support that idea. I've also got versions of libc-8086 and the minix libraries cross compiled, but the libc.a is too large for the ELKS file system, since ELKS has a filesystem implementation problem for any file 512k Just fix the triple indirection and you can have 2Gig files I think 8)
Re: Microwindows/Nano-X version 0.87pre1 released
at extremely high speed. Unlike the Xlib implementation, Nano-X still runs synchronously per client, meaning that once a client request packet is sent, the server waits until the whole packet has arrived until servicing another client. This keeps the server code immensely simpler, while still running very quickly. That kills you on a network or a client hang at the wrong moment. Reblocking the data isnt hard but it can be sorted later. The big thing with reblocking in nanogui will be keeping the max command length low to avoid large buffers
Re: Some questions, esp. for Alan
need to be done once, and it would not be necessary to increment the refcount artificially. Could anyone with a good understanding of the fs code comment on this? I would particularly like to here what Alan thinks. The refcount is bumped otherwise you may get a race when an inode is freed by another user. Secondly there are many places in the code where pointers are checked to see if they are NULL. Frequently the result is not fatal, but by inspecting On the bigger kernel NULL is a valid getblk return for a block I/O error.
Re: Redhat Linux6.o for athlon
The Athlon should run Linux fine. It doesn't have any optimizations from a kernel standpoint, but that'll come in time. They are in 2.3.x. I have 2.2.x patches but they arent generally available. If you get an athlon, you're going to be paying for floating point performance, and not neccessarily everyday speed. You can save yourself a tremendous amount of money by purchasing a Celeron 550, that'll whoop a p3 550, sans coppermine. The Athlon is faster on both integer, memory bandwidth and fpu, but a celeron isnt that much slower and is a lot cheaper.
Re: Intro
development environment with an embedded OS. In order to do this I must add SLIP PLIP to ELKS, I would like to get in contact with the relevant ppl to find out what is being done, and what needs to be done on the networking layer. We dont really have a networking layer. I don't that is in itself a problem since you can prove you send/receive frames correctly and the rest is someone elses problem. There are some ideas for the stack kicking around. One thing for sure. The stack will be a userspace app. Also if anyone has any ideas on getting an EEPROM to boot on an old 8086 laptop, I would be greatfull :) Develop using DOSemu on Linux. It saves that annoying reboot cycle, and you can use the DOSemu ioport logging to debug it ;)
Re: Linux on 486 without fdd/hdd
In my proposed setup I don't have hdd/fdd. I am just having CDROM drive and 16MB RAM, 486 PC. I am interested in booting linux from CDROM and run a browser like Netscape from the same CD. Wrong list. This list is for Linux on 286 or lower CPU machines Alan
Re: ELKS - init
one more thing: the `date.c' does nothing about setting the date. can we use anything else than BIOS calls to do that? If the machine has a CMOS clock (note XT's dont generally have this) you can do it in userspace by hitting the I/O ports. Its not really worth putting in kernel on such a small box. Alan
Re: Linux 8086 TCP/IP stack options - anyone for 6502-C
I might be able to take a look, it has been a while since I did any 6502 assembly, but ... BTW is their any reason why we don't do a full re-implementation. It can't be that bad. If you want to write one from scratch sure go ahead and do it. Alan
Re: Stability
The only reason I suggested using 0.1 as the stable tree is because we are currently heading towards making 0.1.0 a stable version. Well we've never applied any idea of stable/not before 1.0 to mainstream Linux. I think tradition is 0.x = unfinished Alan
Re: Getting ELKS
drive. The processor is a NEC V20. I would like to use the machine for something other than a oversized door-stop. You could saw it in half and use it as too suitable size doorstops ? 1) Will ELKS work on this machine? It tends to use the BIOS so probably 2) What do I need to download to get the entire ELKS package (including an Xwindow environment package)? You are unlikely to ever see X on a machine that prehistoric. THere is a gui in early development. 4) What, if any, documentation is available? Very little. This is at the "my god I installed to hard disk and its still there" stage system. 5) What is the current state of interconnectivity in ELKS (ie: ppp, terminal emulator, TCP/IP, etc...) terminal emulation should work. No ppp or tcp/ip Alan
Linux 8086 TCP/IP stack options - anyone for 6502-C
Also, on another note, in catching signals in Linux from the terminal emulator, I attempt to send them to the process group with killpg(). This routine under ELKS causes an undefined symbol getgpid() when linking. It appears there's an error in linux-8086 libc. That should be getpgrp() I think I've been rummaging around following some leads from from Kira on Linuxnet and now we need to find someone who wants to do 6502-C conversions or Z80-C conversions (the 6502 one looks the best) Phil Blundells 6502 TCP/IP stack - http://www.tazenda.demon.co.uk/phil/iprom.S On the Z80 side there is http://www.altsoft.demon.co.uk/cpcip/ which seems to have a long way to goon TCP (the hard bit) The 6502 one is interesting cos Phil Blundell appears to be the same one as the Linux guy so hopefully we can get it GPL'd Alan
Re: Licensing summary
I disagree. If a vendor can take the proprietary route, he probably will. That doesnt back up experience. The only vendor who wants to take a proprietary route is one for whom this is 'core technology'. To everyone else its overhead and overheads want reducing so you make more profit on the product. BTW, the MPL has a serious flaw in that you can avoid contributing stuff back to the project just by putting it in a separate file. Same with the LGPL, you just put it inside or outside the library.
Re: Request for comments - Microwindows
Actually, the BSD and X licenses best reflect the needs of embedded developers. The X one does. The BSD original format doesnt. The advertising clause got a netbsd router project by a very large networking company canned
Re: Request for comments - Microwindows
So even though David Bell said "Permission is granted to use, distribute, or modify this source, provided that this copyright notice remain intact" we can say that now his code is subject to another agreement, the LGPL? Doesn't the LGPL restrict more than the above? Yes. But that is allowed. You can take his work and use it as allowed by his license to create a derivative work - his license allows this. What you cannot do is stop someone taking David Bell's original work and using it under David Bell's license alone. The derivative work (the combination) is differently licensed to the original code he wrote. Also, can we have a GPL license on the server and an LGPL license on the applications? Can we have both even if we allow linked-in apps and client/server apps? It gets complicated in the linked in case. Alan
Re: Request for comments - Microwindows
people will be able to hide drivers from us, as I think this has the potential to seriously injure Micro*'s open-source value. So has the lack of support for on devices where specs simply aren't openly available. In the longer term XFree86 has gained by the fact vendors wont ship binary only kit. Its now at the point that 'Linux' is a question big vendors ask and that 'no' costs you bulk sales
Re: Request for comments - Microwindows
In the longer term XFree86 has gained by the fact vendors wont ship binary only kit. Its now at the point that 'Linux' is a question big vendors ask and that 'no' costs you bulk sales I don't understand. What do you mean? "I want to make Linux support an XYZ card" "Im sorry we only allow binary drivers" "oh goodbye" [nowdays] "Hi majorvendor foo purchasing here we want to source 50,000 XYZ cards" "Oh great yes, expenses paid lunch coming right up" "We do want Linux support as we may be certifying our stuff for Linux" "Oh.. umm. I need to talk to the boss" And vendors are changing policy for these kind of reasons
Re: Stupid licensing thread (Was: Request for comments - Microwindows)
As long as the API and/or messaging protocol are open spec, then anyone can write their own library. X is an example, XFree uses opensource license, metrox and accelx used closed. Same function, same result, but they had to write their own library. [Equally a server] Actually they wouldn't have had to if they didn't want to. The XFree license permits closed source use. Indeed. And while LGPL might be better in some ways than the BSD license X wouldnt be where it is today had it had a GPL library
Re: Another ELKS idea for shared libraries
: for task switching), can bcc handle that? Or create something like an : indirect jump and glue code in the library. The indirect jump and glue code is exactly what is needed out of bcc. currently, it doesn't generate any of that kind of code. It also cant do that on an 8086 without ruining swapping/defrag
Re: Another ELKS idea for shared libraries
As I mentioned before, if this were performed with code segments only, then they could still be shared with the resulting memory decrease benefit. But is outweighed by the cost of no swapping or defragmentation In fact, with a ridiculous increase in code size, all absolute locations could use a [bx] register offset to get to a small table of hard adresses, just like the ELF .got section is implemented. I'm not recommending this, though, since we're already short on cseg space. You need to cover call/ret sequences. It is doable but hard
Re: there's still life in the Z80
http://www.zilog.com/ez80/ Someone now design a cool linux box with the ez80. Would it be possible as it has a MMU and supports 16mb of memory ? You'd need to get the compiler kit working first, but I guess so
Re: get compile error compiling objdump85
Basically, the time-honored FILE * constants stdin, stdout, and stderr are no longer constant. The offending line is: They've never been constants in all cases. done this? It's going to screw up alot of old programs. only broken ones as far as standards believe
Re: [fs/select] problem with get_user()
What is needed is a similar function, perhaps peekd() which
would return a long. Then we could define a macro get_user_long()
You mean
unsigned long peekd(unsigned short *x)
{
return peekw(x)(peekw(x+1)8);
}
Re: 8051 or Z80 Can run ELKS
Does this include the 8051 8031 8751 etc?? Are there other linux or otherwise UNIX compatible embedded system OS that works in Z80 an 8051? UZI runs on a Z80
Re: SIBO/Psion Elks
1). Reduced character size to 8x8 to increase screen size and save memory (the font is held in Data segment) Can you not find the Psion font in rom ? Also you could push the font into its own segment and 'borrow' ES momentarily with a cli around a single char render. 1). The current version of Init (in elkscmd) seems to need /var/utcp to be exist, what does this do and should this file be writable (which won't be possible with a read only file system!)? Eventually you are going to need a ram disk. 2). PS requires '/proc', but I can't see any code where this 'created'. The mainstream Linux has a /proc we don't. The intention is to make /proc dig around in /dev/kmem 1). I still can't get Config #DEF's to link through to .S files for parsing. Is this working on other people's machines? (this is making life kind of difficult). .S files should go via the C pre processor. .s files dont 2). The build tree doesn't fully work with all the options. For example if you don't have loadable modules, 'sys_dlload' is not defined and causes a build error (have to then change the auto generated arch/xxx/kernel/entry.c file). Yep. I noticed this. Thats a case of clean them up as you find them If someone could summarise what needs to be where and why (for a minimum system, remember I'm working with a 128K disk for the time being) it would Absolute minimum you probably want init (hacked without /var/utmp if need be) although this is optional. You want ash the shell (which can be your init) and a few basic binaries.
Re: SIBO/Psion Elks
exist, what does this do and should this file be writable (which won't be possible with a read only file system!)? Eventually you are going to need a ram disk. [Simon Wood] Why ??? I agree that in a 'PC' type environment you will need disk storage, but there are many applications for ELKS that will not... In this specific case 'init' would need to create a RAM disk for /var before it continued booting - seems a suspect way of doing it to me. Then you will need to do hacking otherwise - unix tools tend to assume disk scratch space exists. And on this line in whinging 'clock' talks directly to hardware (which in my case doesn't exist!) - it should be through a clock driver! No. The clock driver itself would take up valuable permanent space in the kernel. It means you need the right clock binary for the hardware but it saves you kernel space. Linux 386 is a bit different but on an 8086 its best in luser space .S files should go via the C pre processor. .s files dont [Simon Wood] Yep I get the concept, but I can't get it to work :-(, how are the config #DEF's passed through Makefile to gcc?? (they certainly don't appear if you do 'gcc -dD'). It should be including the config header file.
Re: 8086 = 8057?
Are the 8086 instructions compatible with any intel microcontrollers such as the 8051, 8057 80257 MC80257 etc? If so, very Not to my knowledge. cool linux machines with LCD displays and cheap MCUs can be build for the third world :) . Any ideas anyone?? Low end ARM chips like the 7110 have all the glue on board for LCD, ram decode etc and are pretty cheap. They even have an MMU and run 'real' Linux
Re: cheep linux machines
...away from the rest of the process, the bottleneck seems to be the machine layout... not the OS. I just cant seem to find a good list of all available mcus that run linux. the ARM website says nothing of the OLD ARMs like arm2/3, it starts with ARM6 which could be too much and too ARM2/3 arent available any more. They haven't been for years. They need a ton of glue logic. Age != pricing (in EU/US anyway) expensive. There has to be a website on the CHIPS not boards or machines that can run linux.. and the addition of (appx) pricing would be appreciated. Also does anyone know of intel MCUs like 8057 able to run 8086 code?? That would bring the cost down to like 2.5$ :) . The ones I know about Running ELKS - so unfinished kernel as yet, but getting there, no networking no MMU, small apps 801EC86 etc Embedded 8086 chips (Intel/AMD/...) Some of these are very cheap. Psion sell a box using an embedded x86 variant to end users for UKP100 (US$160) or so (the sienna) running their own OS (not linux) Running UC/Linux - no MMU, strange libc 68451 "Dragonball" CPU - Motorola - as used in the palmpilot heavily designed for low chip count PDA's Running Real Linux Cirrus ARM 7110 - 19MHz ARM7 CPU, on board lcd driver, gpio, ram decode etc etc. Aimed at PDA's (used on Psion 5) Motorola PPC - assorted chips mostly oriented to low chip count communications tasks. ie CPU + 4xSCC + other logic Mips- various chips but most vendors sell MIPS as a VLSI cell - ie you do the chip design they integrate all the bits you want - high volume option only. One of the real big issues with this is all the modern chips tend to use advanced packaging techniques making them hard to build onto boards without fancy tools. Alan
Re: doa.org administrivia
Hi all, At 10:32am GMT, 18th July 1999, a host on the domain shared by doa.org was entered into the ORBS database. As a result, some users have had mail bounce from the developers mailing list. Any mail address which bounces to this list with an error such as the ORBS error, or a 'user does not exist' error will be removed from the mailing list. This is what happens when you use automatic mail rejection, it saves you 1 spam a day and sends me 10 bounces a day. It saves me 40 spams a day. It also encourages the admin of sites that are a problem to fix them. Also orbs blocks specific hosts only. They dont block a domain because of a single host
Re: Microwindows for Hercules
No need. MicroWindows handles the Bresenham algorithm in the mid level code in devdraw.c. It uses successive calls to drawpixel to make it work. In this way, people like you and me don't have to rewrite bresenham for every card someone wants The code in devdraw.c is very naiive. It assumes pixel plotting is the underlyin op. On many cards line slices are the underlying operation, horizontal or vertical. What you probably want to do is generate a series of draw_horizontal(x,y,l) or draw_vertical(x,y,l) calls for most things This might be useful when bitblt is implemented though... Having 32K of offscreen memory is always useful. Alan
Re: doa.org
The web message is not very friendly though! *shocked amusement* WEB PAGE CONTENT: GO AWAY, Your bugging me. Indeed - terrible grammar ;)
Re: SV: herc microwin support
The source code for GEM desktop is AVAILABLE?! I've always wanted it! Where!!?!?! Caldera released it , CP/M and some other oddments from the DR-DOS pile under a no commercial use license. CP/M is elegant code. CP/M 68K is really nice. GEM is just plain ick
Re: Psion ELKS Memory Mangament and Protection.
Your summary seems pretty good. So its 384K base 64K window 64K window (junk) The segment switching for ramdisks is a non issue. We are either writing to the code or data segment, so you an do large I/O's to the window boundary using one segment for the target and one for the source. That only gets vaguely hairy when you want to allow a smaller program to be running across a 64K boundary. The mm handling for that kind of 'aligned as we need within any 64K block' is fun stuff. Another amusement here is that if you are prepared to accept 56K as the maximum size for data, you can pull some very interesting stunts with the kernel stacks, allowing for many more processes - and getting it to scale per bank. Basically you put kernel DS at 0x5000+8K so it ends at 0x5FFF+8K Now you put the kernel stacks at DS:E000 and you have 16 kernel stacks per bank. As your banks grow your number of stacks and thus processes go- indeed most of the task struct can go here too with a bit of care. This is how V7 works on a PDP11 using the 8K segments they had. The so called 'u area' is all the crap a process needs that isnt needed when it isnt running. You'd need to change the wait queue code a little to handle this but not much. The memory protection is crude, but will catch accidental errors easily. You can't catch deliberate attacks on such a box so why try. Now how do the SSD's work 8) Alan
Re: z80 *ix...
Hey, recently a friend of mine mentioned something called UZI to me, which supposedly was/is a *ix for the z80, and ported to the z280. Anyone else more familiar on it? oak.oakland.edu:/pub/cpm/uzi
Re: Capabilities
A reloc table in the binary (like DOS EXE files) could work for code at
least (as long as the binaries are immutable while a process is using
them, and the programs are careful about self-modifying code).
No it doesnt
extern int foo1();
int foo2()
{
x=foo1;
x();
}
You need 32bit pointers and until you are in 286 mode you also need to do
basically impossible fixups
Re: Capabilities
Good points. If we stayed restricted to large code segments only, however, then we could run much larger programs (like the bcc compiler, for one), if we restricted ourselves to the following: bcc fitted in 64K on Minix built with ack so thats a BCC problem ... o Dont' swap code that has the multi-code segment bit set in the exe hdr. (This isn't that big a deal, especially if it lets us run real programs...) Its a very big deal o Fork isn't a problem if we use shared code segments, and don't have far data pointers. Thats the only bit I suspect is true
Re: Capabilities
: You then need a 386. 64K is the limit. The original work I did was designed : to be easy to run in 286 protected mode once you got rid of any BIOS interfaces. : Remind me - what then is the benefit of protected mode? Merely separate address spaces? You get two things in 286 protected mode 1. You take exceptions if you try and go out of your segments 2. You get 16Mbytes of addressable ram
Re: Capabilities
I was wondering if KA9Q NOS might be used as a basis for ELKS TCP/IP, rather than starting again from scratch... $50 a copy to non education or amateur radio users. Unless that is Phil is willing to change his licensing policy
Re: Capabilities
This brings up my wishlist again, that we should have bcc compiler support for medium and large models for x86. Al Ridoch doesn't want to move to supporting the _far keyword. I think that it would buy us alot, especially if we're going to stick with old outdated processors like the 8086. Al is right however. Going to far screws you up totally on things like swapping and makes fork truely horrible. Don't go that way except on a 286
Re: SV: Editor
'vi' is powerful? I think it looks kind of like EDLIN. Must scare a lot of people off, considering EDLIN's capabilities. I prefer editors like edit vi is powerful. Powerful and usable are two often non-intersecting fields. How is the ELKS API accessed in assembly? I think I'll need that if I'm going to code one of those editors. Its calls via int 0x80. Take a look at the C library source. You shouldnt need any asm. BTW if you want edlin there is a unix clone called 'deadlin' or 'dedlin' somewhere
Re: ELKS video drivers...
On Mon, 17 May 1999, Greg Haerr wrote: 1. IBM MDA. no graphics support... Umm, are you sure? We used to run windows 3.0 on amber monochrome monitors at college. I am also unsure. Can someone with a clue speak up? MDA is text only, Hercules is the mono graphics display
Re: nanoGui development
Why is that? to keep the kernel smaller? My initial idea matched with Yes. And also because you may be restoring to another graphical app..
Re: GEM (WAS Re: vgalib)
The GEM code is neat, and it *is* GPL'd, so maybe we can play with it, but it's always more fun to write our own code than port. =) Sure, it's more fun, but if you port code, then you can actually get some sort of relatively fast turnover of applications. GEM is btw pretty limited. You can't for example draw except to the top window in most versions of GEM
Re: some questions
There is an ELKS port to the Z80 ? That sounds nice. Can you tell me more about it ? Would be great to run Linux on my beloved Z80 machines in my "Museum". Why is ist stopped ? ELKS is too big for this - look at UZI (ftp://oak.oakland.edu/CPM) and OMU (http://tallyho.bc.nu/~steve) Alan
Re: 32 bit OS for ARM
The linux kernel is too large for embedded system. We may no want a file system at all. One way to do this is to implement the application as the init program called by the kernel after booting, or just find the place that opens and executes init and change it to run the application actually linked with the kernel. Thats relatively easy to do with linux 2.2, You just call kernel_thread() to run a linked in task instead of mounting an fs and loading fs code. Alan
Re: ELKS development ideas
Also, your point about using bios to get memory from pmode would allow us to use a fancier scheme (like the existing linux kernel's) On a 286 or higher the right answer is quite simply to run in 286 protected mode - its not _that_ hard to do. in order to get other memory? Or is that what the EMM specs are for? EMM is what you need for 8086 - paged memory banks. Generally people used loadable DOS drivers so you'd need to dismember those to see what they used for bank switches (or run them in DOSemu and log port accesses). EMM as a banked disk cache, ram disk, swap is perfectly sensible Alan
Re: [linuxce-devel] Re: Web browser ported to Microwindows
I have heard a lot of things about konqueror, and much of it is not really good. I really cant tell, I haven't seen anything of it. Is it as good as the developers say it is ? Not in my opinion, but its also not as bad as some of the people who complain about it make out either
Re: [linuxce-devel] Re: Web browser ported to Microwindows
Yes, I suppose it would be good news also, if only their browser was GPL (or some other genuinely free open-source license). However, AFAICT it is thoroughly proprietary. Maybe they will choose to contribute back to Microwindows. However, since Microwindows isn't GPL (it's MPL) they have no obligation to do so. For a small browser the new gtkhtml work is looking very promising as a core. Its actually the KDE khtmlw widget (that nice fast but not full of js/java/.. kfm viewer) aka 'konqueror' redone into C with a lot more gui independance. Once its stable as a gtk widget it seems a good basis for an html viewer for Nanogui/microwindows.
Re: My embedded linux project
Chipsets? I'm building custom hardware because I want to get away from chipsets. completely unnecessary for my task. Plus, I'd have to go thru the expense of developing a custom bios and its not worth it. How much CPU power do you actually need. If you can lay your own high speed boards out the Cyrix MediaGX is basically a two chip set (socket 7 cpu with extras) and a 5520. You could then leave most of the peripheral intefaces you don't care about (audio/video ...) unattached Alan
Re: bcc under ELKS?
Yes, I know that IBM-PC is not a Mac and does not have all many registers but ELKS does not use all of them anyway! IIRC the ES register is not used and thus can be used in much the same way. Also, PC code is usually riddled with Int calls so why not use something like this... Once you implement memory defragmentation and swapping you can't just do intersegment calls on an 8086, you can on 286 protected mode. Since playing with per task LDT stuff on 286 pm is seriously unfunny the first time you try it I'd strongly suggest getting the 64/64k limited stuff working on an 80286 pm first
