Jeff Garzik wrote:
quoted text
> James Richard Tyrer wrote:
>> Intel claims that they provide complete documentation.  VIA isn't that 
> 
> Intel has certainly -not- provided full docs.
> 
An open source X driver with 3D acceleration exists.  How was that 
developed without documentation?
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> 
>> clear about releasing a data sheet.  They seem to want an NDA which I 
>> have no problem with since I have no interest in reverse engineering 
>> their chips.
> 
> VIA does indeed provide GPU docs under NDA.
> 
> 
>> open source driver for Intel.  The VIA driver is only for a frame buffer.
> 
> False.  Trivial inspection shows a full, open source, 2D/3D accelerated 
> driver for VIA is available.  Taking two seconds to do "ls 
> drivers/char/drm" in the kernel source tree would have shown you reality.
> 
Is that for the UniChorme chip?  The dox says that it is for the 
MVP3/Apollo chip set.

The driver which VIA supplies for the UniChrome chip (FBDev_Lite) is a 
frame buffer
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> 
>> The Linux market isn't asking them for an investment.  What we have 
>> been asking for is the full documentation of the chips.  Note that 
>> graphics 
> 
> False.  Full documentation is an investment that requires legal $$$, 
> plus opportunity cost, plus potential cost of your company's primary 
> product being supported at a sub-standard level.
> 
> 
>> chips are an anomaly here.  All other chips I know of have full 
>> documentation available.
> 
> Ok that is just laughable.  There are so many counter-examples its not 
> even funny.  Easy examples:  Ethernet, SATA (areas I deal with every day 
> in the Linux kernel)

Say WHAT?  How do they sell chips if they won't supply documentation?

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> and winmodems 

A winmodem is not a chip, it is a board or module.  Some may have custom 
chips, but they started out as a DAC and an ADC -- better ones also have 
a DSP or controller chip.  What they won't give out is the driver for 
the board, but then some of the manufacturers started giving out a 
driver for Linux.  This is a situation similar to the graphics drivers. 
  The driver is proprietary, but there is stuff in it that can't be 
patented.

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> all have hardware vendors that refuse to give out docs.
> 
I have not looked at SATA chips, but all the NIC chips I have looked at 
are documented.  Perhaps you are using the word "documentation" in some 
different sense.  If they tell you what all the registers are for, that 
is full documentation.
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> 
>>> The law guarantees that they cannot go into the open source market in
>>> a big way.
>>
>> Explain this please!
>>
>> I suspect that the problem is that they don't have a patent.  They can 
> 
> <blink>  Um...  ATI and NV have bunches of patents.  Search the patent 
> database.  Graphics is a patent minefield.  

But, there is OpenGL which stands as prior art.  Unfortunately, 
companies patent everything that they can knowing full well that 90% or 
more of it won't stand up if challenged.

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> Have you been reading this thread at all?

Perhaps a few more words would have made this clearer.  They are 
obviously trying to protect something which is not patented.
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> 
If everything were protected by valid patents, then it has all been 
publicly disclosed and there is no reason not to provide documentation.
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> 
>> copyright the drivers and copyright the chip, but that doesn't prevent 
>> reverse engineering of the chip, or making a clean room clone.
> 
> Without a patent grant, you would be infringing if you distributed the 
> RE work product.

This issue is currently an area of contention.  ARM has managed to get 
all of the clones taken off the market.  But, that is a processor, not 
an ASIC.  OTOH, clean room RE of the IBM-PC BIOS was determined not to 
be a copyright infringement.  If they tell me what all the registers are 
for and what the commands do, and I independently design a chip that 
does exactly the same thing -- produces exactly the same output -- with 
NO knowledge of the inner workings of their chip, have I violated a 
patent.  I doubt it.  You can't patent a register layout.  You can't 
patent an instruction set (specifically you can't patent a programing 
language).  The patents would be on the methods that the internals of 
the chip are implemented with and if I do a clean room clone, I 
deliberately don't know anything about that.

-- 
JRT
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