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Manpages svgalib.mach32Section: Svgalib User Manual (7)Updated: 1 August 1997 Index Return to Main Contents NAMEsvgalib.mach32 - Information on the Mach32 chipset driverTABLE OF CONTENTS0. Introduction1. Specifying pixel clocks 2. Copyrights 3. The mach32info utility 4. Third party cards 5. Logical linewidth 6. Noisy video signals 7. The configuration EEPROM 8. EEPROM woes 9. The Mach32Eeprom command 10. Setup of the memory aperture (linear framebuffer) 11. Accelerator support and other weird features 12. Ramdacs 13. Meaning of the detection message from svgalib 14. Conclusions 0. INTRODUCTIONThe driver should allow you to use any of the graph-modes your Mach32 card supports. Note that there is no support for <8bpp modes and that I won't ever implement that because I don't see any reason for doing so. All standard VGA-modes are supported, of course (by using the standard VGA driver routines).If you configured your Mach32 for a memory aperture and it is at least as big as the memory of your card (that is, not a 1MB memory aperture for a 2MB card) support for linear frame buffer access of svgalib is given. Auto detection of the Mach32 seems not to work on all cards. That's really strange since I got the code from the X people. It should be OK regardless of my docs. Well, I fixed that (hopefully). Actually the bug was found by Daniel Lee Jackson (djackson@ichips.intel.com). (Thanks again.. It was so silly... I would have never found it) If you still have problems just put a chipset Mach32 in your config file. 1. SPECIFYING PIXEL CLOCKSWARNING! The Mach32 driver needs to know correct clock frequencies for graceful DAC configuration. Wrong clocks may damage your card! However, this version contains code for automatic clock detection. Since clock detection is time critical, please do it on a completely idle system. Then put the printed out clocks line in your libvga.config(5) file.The driver tries to do this for you. After that, you can restart whatever svgalib program you used and you are set. If you already put a clocks line in your config by hand, comment it out to have the driver check your clocks. Since clock probing is time critical, values differ from time to time, you may try it multiple times and see which values seem to be most exact. You can also compare them with the standard clock chips for Mach32 cards in libvga.config(5)). The clock probing relies on the 7th clock being 44.9MHz as this is what Xfree does. If this is not true (and it is not always), probing is hosed. See libvga.config(5) for a list of the clocks used by common svgalib cards. 2. COPYRIGHTSSome tiny routines are copied from Xfree86. The clock detection code is almost just copied. So I repeat the copyright statements for these parts here:
Copyright 1992 by Orest Zborowski <obz@Kodak.com>
Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the names of Orest Zborowski and David Wexelblat not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. Orest Zborowski and David Wexelblat make no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. Orest Zborowski and David Wexelblat disclaim all warranties with regard to this software, including all implied warranties of merchantability and fitness, in no event shall Orest Zborowski or David Wexelblat be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of this software.
Copyright 1990,91 by Thomas Roell, Dinkelscherben, Germany.
Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of Thomas Roell not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. Thomas Roell makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. Thomas Roell, Kevin E. Martin, and Rickard E. Faith disclaim all warranties with regard to this software, including all implied warranties of merchantability and fitness, in no event shall the authors be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of this software. Author: Thomas Roell, roell@informatik.tu-muenchen.de
Rewritten for the 8514/A by Kevin E. Martin (martin@cs.unc.edu)
And here is my own copyright: This driver is free software; you can redistribute it and/or modify it without any restrictions. This library is distributed in the hope that it will be useful, but without any warranty. Copyright 1994 by Michael Weller Email addresses as of this writing: eowmob@exp-math.uni-essen.de mat42b@spi.power.uni-essen.de Michael Weller disclaims all warranties with regard to this software, including all implied warranties of merchantability and fitness, in no event shall Michael Weller be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of this software. 3. THE MACH32INFO UTILITYThe mach32info(6) utility or demo reads out all configuration registers and the configuration EEPROM of your Mach32 card. If there is a problem with the particular card you have, compile and run the utility in the mach32/ directory of the svgalib distribution and send it's stdout to me This might also be useful if you need a lot of options (e.g. clocks on new models?) to get it to work so that this can be done automatically in future versions.4. THIRD PARTY CARDSI got a few reports about AST systems with onboard Mach32. They do feature an incompatible EEPROM setup, but I think I got around that. Nevertheless the Mach32 chipset driver doesn't work out of the box on any AST system I heard of.Since original ATI Mach32 demos and tools don't work as well, I've to claim that the Mach32 on these AST systems does not conform to ATI's Mach32 docs. Fortunately, Vernon C. Hoxie <vern@zebra.alphacdc.com> found a work around after years (really!) of investigating. AST Mach32 seems to work now. The work around was also submitted to Xfree and will be incorporated to allow running it on the AST hardware too in recent versions. Please read on the misc_ctl command below. Dell users should have a look at the vendor, ramdac, and svgaclocks commands below (if they have problems with the default settings). Commands to support third party cardsI had to learn that those cards seem to use not only non standard clocks for the Mach32, but also for the included SVGA. However, since people often like to use proprietary, non standard VGA (read 80x25) textmodes, the Mach32 driver has to set the included SVGA to a VGA compatible clock frequency. Otherwise svgalib has problems using plain VGA modes. This screws VGA modes up if these clocks have different values on third party Mach32 cards.
As I mentioned already, Vernon C. Hoxie <vern@zebra.alphacdc.com> really seems to have located the reason for the Mach32 AST problems. Any access to MISC_CTL locks up the card & system. Fortunately MISC_CTL is only used for some DAC fine tuning (actually the setting you can fine tune with the blank command) which is only of barely noticable effect to the screen. The following configuration commands exist to support AST cards:
Finally, for your convenience there exist:
Note that the type of the ramdac can be set more conveniently with the ramdac command. 5. LOGICAL LINEWIDTHAt least my VRAM card seems to be very peculiar about logical linewidths. From my experience a multiple of 64 pels is needed. Your mileage may vary. Use the config file options to adjust it and tell me if your card needs a different value. Include the name and model number of the card and what the correct numbers should be. This is so that I can correct the auto configuration of the driver.If some svgalib application has problems, note that you can force the logical linewidth to the default value from the configfile. Probably this will lead to glitches in some 800x600 resolutions. You can inhibit these resolutions from the configfile as well. Apropos glitches, I found no guidelines as to what clockrates to use due to memory restrictions. I adjusted the driver, such that I get a stable pic in all resolutions. However sometimes the screen is disturbed by heavy video memory accesses. If you don't like that, reduce the clocks used with the maxclock16 or maxclock24 command, resp. This may of course lead to none of the predefined modes being used. Then you can try to define your own mode via the define command. 6. NOISY VIDEO SIGNALSIf you get some flicker or heavy noise on your screen, some fine tuning may be needed. My docs didn't give me hints as to what each card can stand. Especially DRAM cards may give problems (I've VRAM). In that case, use the fine tuning config commands and send me your results along with the output of mach32info(6). Then I can include them in my next release.Fine-tuning configuration commandsFirst you should think about the maxclock* configuration commands to reduce pixel clocks used for each color depth. Especially important for DRAM cards is the video FIFO depth used to queue memory values for writing to the screen. Here is a command to set this value for the 8bpp modes:
vfifo16 number
Note that these commands may vanish again once they are no longer needed for debugging purposes. There is no 320x200 mode in the EEPROM of the Mach32 at all, however I defined one in the default configuration file for you. This is the best thing I could get up on my card/screen. Note that it will probably have big borders on your screen, and black lines in between the pixel lines. This is because of the lack of low clocks < 16MHz on the Mach32 and the lack of a line doubling mode as VGA has. The Mach32 is not intended for such low resolutions. If you find a better mode or have an idea, please let me know. You can also just remove my timings from the default configuration file. 7. THE CONFIGURATION EEPROMAh yes, about the EEPROM, I figured out how to read out the Mach32 EEPROM. I did it by disassembling the BIOS routine mentioned in the docs. I then redid it in C. The driver will use everything it finds there.Use the Mach32 install tools (they should have reached you together with your Mach32 VGA card) to setup your card/monitor combo correctly. The monitors setting from the config file (or default of 35kHz or something) will be obeyed by the driver nevertheless (for safety!). As you probably know already, accessing the EEPROM causes some screen flickering. If this annoys you (or even worse your monitor) have a look at the mach32eeprom command described below. This allows you to put the data from the EEPROM into a file and which can be read whenever it is required. Don't even think about changing the contents of the file. (There is an easily faked checksum in it.). Anyway the driver ensures (hopefully) that no damage can be caused. Also, if some mode is not well aligned on your screen or you don't like it's sync frequency, consider using the Mach32 install utility (setup for custom monitor) and set one up interactively. If there is no valid faster (higher VSYNC) standard mode given in the EEPROM the driver will use that mode. You will find that this is fun compared with calculating video timings for /etc/XF86Config or /etc/vga/libvga.config. However the install utility does restrict the maximum pixel depth for custom modes sometimes unneeded hard and the driver obeys that. (Hmm.. actually it should be smart enough to decide itself which pixel depth it can use in that mode.) Since the standard modes are usually only slightly shifted to one side a file with the configuration commands representing the standard modes is given in mach32/mach32.std-modes in the svgalib distribution. You can use these as a starting point. But here are some real problems: 8. EEPROM WOESI got 2 reports of people having problems with incorrect EEPROM checksums. Both had motherboards with onboard Mach32 VGA's from AST. I guessed a checksum algorithm from those reports and put this in the code in addition to the standard ATI style. Still I got a report of someone whose EEPROM was completely empty. If you have problems with checksums send me the output of mach32info(6) and I'll see what I can do.By default svgalib writes a complaining message and ignores the contents. You can have svgalib ignore the checksum and contents with the configuration command mach32eeprom ignore Then you can decide to use the partial info that is still in it. Use mach32eeprom ignore usetimings to use the videomodes that are defined in the EEPROM (if no better modes are known by the driver). This is usually safe, because the driver knows which modes are safe for your hardware (if clocks, monitor and ramdac are configured correctly). You can also allow the driver to use the configuration for the linear frame buffer in the EEPROM: mach32eeprom ignore useaperture or mach32eeprom ignore usetimings useaperture However I discourage this because the driver will just enable what the EEPROM says about the aperture. Use mach32info(6) to check the address it will choose is safe. It might be better to use setuplinear to set up a 4MB aperture at a free address range. 9. THE MACH32EEPROM COMMANDThe mach32eeprom allows to work around these problems. Here is the complete description for this configuration command.
Due to problems with some boards this command got heavily expanded:
10. SETUP OF THE MEMORY APERTURE (LINEAR FRAMEBUFFER)Due to poor design, Xfree86 insists on setting up the aperture itself. It doesn't reset the original settings at a VC switch once it runs. You should not start X for the first time after a boot as long as an svgalib application is running. This will result in pre X values being restored at a VC switch by svgalib. If you use svgalib and XF86_Mach32 together, run X first or at least do not start it while any svgalib appl. is still running. After X was started once you can use svgalib and X in all combinations w/o any problems. Xfree uses whatever address is given in the MEM_CFG Mach32 register for a 4MB aperture, even if the aperture is not already enabled and the value in this register is pointless garbage. This is IMHO a dangerous bug as some systems may work only with a 1MB aperture. However, usage of a correct EEPROM circumvents any such problems. If you cannot use that, use mach32info (6) to find the address in MEM_CFG. Then, if it is a senseable setting for your system, enable a 4MB aperture at that address with setuplinear. Ensure that no other card or memory uses the address range you choose. 11. ACCELERATOR SUPPORT AND OTHER WEIRD FEATURESThis version now has support for all accelerator functions of svgalib. However they were intended for use with the cirrus chips. It may happen that at runtime they find they cannot emulate the function actually requested. Then you should disable the corresponding blit function (at least for that application) with the blit config command.Data transfer between the host and the Mach32 is normally via I/O. This proved to be pretty slow. If a big enough aperture is available, a simple memory copy is used instead. This is usually much faster. You can change which method is used with the blit command. This I/O option affects only vga_imageblt(3). The other functions are incredible fast. For type 2 DACS, there is support for 8 bit per color (instead of the normal 6) in the RGB triple in the color lookup table of the 256 color modes. This can be enabled by an application, if it supports it. The testaccel(6) demo uses it if supported by your hardware. You can use vga_ext_set(3) to use it from your programs. 12. RAMDACSMach32 Ramdacs are specified by a type in range 1 .. 5. This type can be queried from the Mach32 and then specifies how to set up the ramdac. A list of actual hardware chips used for each type exists, but is not of much use. The Mach32 will return a type and the ramdac will be completely hardware compatible to one of the given type.Type 1 and 4 Dacs need different clock frequencies for high colormodes. For 32K/64K colormodes the frequencies have to be doubled and for 16M colors (type 4 only) they have to be tripled. I followed the ATI scheme and did this internally. However this means that for 32K/64K you can use only clocks for which the doubled frequencies can be generated as well. This is no hard restriction as the 16 clocks of the Mach32 can be divided by 2. Thus if you setup some mode yourself try to use one of the divided clocks in your timings and I can use the undivided clocks internally. It is a real restriction for 16M colors. ATI themself only supports 25MHz (640x480) here by use of a 75MHz clock. Depending on your clock chip other values may be usable as well. Even the doubled/tripled clocks have to be less than the magic 80 MHz. However the driver does all this itself. It may just happen that some of the predefined or one of your handmade mode-timings can't be used because the clock that is used cannot be doubled/tripled. Even though there is already some tolerance in the driver you may fix that by slighty changing the clock values that you set with the clocks command. But note that this will as well affect the ability of the driver to calculate video timings and thus it ability to check the monitor and DAC safety restrictions. In addition (in complete contrast to my original ATI docs) RAMDAC 4 does not support RGB with blue byte first but only with red first. This required special handling and me adding a bunch of functions to all modules of svgalib and vgagl. The added functions are of lower performance than the usual functions. However most data has to be completely mangled, so I doubt that it can be done much faster. Sorry. Of course, I might have forgotten to port some parts or even confused things. About bugs in the gl and drawing libs, please ask Harm. But then, I'm able to emulate a BGR ramdac on my card, so I should even be able to reproduce your problems. Recently I hear often about type 6 ramdacs in non ATI Mach32 cards. There exists no info about these dacs, thus I cannot support them. The driver assumes unknown DACs can stand up to 80MHz in 256 color clut modes and does not touch the ramdac (that is, assumes it is in the 256 color mode already) To get rid of the warning message you can use the
13. MEANING OF THE DETECTION MESSAGE FROM SVGALIBSome programs (which do not switch it off) will show aUsing Mach32 version (sizeM at adrM (how), memK mem, DAC dactype) line. This will show up in testlinear(6) etc but will probably scroll away when you use vgatest(6). In this line:
If mem, dactype and/or the chipset were enforced with chipset from the configuration file or vga_setchipsetandfeatures(3) a forced will be appended to the line. 14. CONCLUSIONSA final word: I have an ATI ULTRA PRO/2MB/EISA with a Type 2 DAC. My monitor is an EIZO F550i-M. Everything I tried works on it like a charm. However, I couldn't try it with other machines myself and esp. other DAC's. Fortunately the Type 2 DAC is the worst to code. So I will probably have gotten the other DAC's right. But please be warned!I did my very best to code the driver to support the other DAC's by just reading the docs. But i can't give any definitive guarantee for it to work or even not damaging your hardware. So please be careful! Note that you will have to set the environment variable SVGALIB_MACH32 to ILLTRYIT if your DAC is not type 0, 2, 3 or 4. This will of course change if no one with a DAC equal to 1 or 5 has serious problems. If you have a different DAC, making patches to support your card will be much more helpful instead of just complaining. If you have a different DAC that works well tell me as well such that I can remove the need for SVGALIB_MACH32 in the next release. Still, even now, after years, I got no reports of a Mach32 card with a type 1 or 5 ramdac. Go figure.
Thank you for your audience and wishes you will enjoy this driver,
FILES/etc/vga/libvga.config/etc/vga/mach32.eeprom SEE ALSOsvgalib(7), libvga.config(5), mach32info(6).AUTHORThe Mach32 driver and this documentation was written by Michael Weller <eowmob@exp-math.uni-essen.de>.
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