MPC8272ADS and frame buffer

MPC8272ADS and frame buffer

[Federico Lucifredi]

Hello Federico,
    It turns out you can solve your problem by using the Epson SD13806 
evaluation board (s5u13806b00c). It comes with drivers distributed, 
inanely enough, as a patch for a specific kernel, so prepare for some 
hand-patching. Other than that, it works.

    Love answering myself :)  -Federico

>Hello Linux-PPCers,
>    I have a quick one: I am looking at the Arabella kernel on the 
>MPC8272ADS, which I am planning to use as a prototyping platform while 
>we get to figure out a BSP for our custom board.
>
>    Now, I have an Epson card on hand (13806) which I know to be working 
>on ppc, and which has drivers as a kernel patch for 2.4.21, and I have a 
>radeon card on hand which I used to like because of its vesa 2.0 
>compliance.  The first brings up the problem of porting the patch to the 
>2.4.26 kernel, which Arabella/Yuli Barcohen customized to the 
>MPC8272ADS. The latter, according to Yuli himself, won't work because of 
>BIOS initialization issues.
>
>    I do not mind buying another card if necessary (time is at a greater 
>premium), but I would like to know that there is a 2.4.6 driver for it 
>or that it is supported by Arabella's kernel.
>
>Anyone here using the Arabella BSP on the 8272ADS with a frame buffer on 
>it ? What setup are you using?
>
>-Federico
>  
>

-- 
_________________________________________
-- "'Problem' is a bleak word for challenge" - Richard Fish

Muad'Dib of Caladan (Federico L. Lucifredi)- Harvard University & BU
http://metcs.bu.edu/~lucifred

Re: MPC8272ADS and frame buffer

[Federico Lucifredi]

Bora Þahin wrote:

>But S1D13806 is showed in the web site as legacy. Instead of it S1D13506 is suggested, which seems
>it has the same properties with 13806... Do you know anything about it?
>
>  
>
hehe - I know, it is an oldie now. I used it because my company had one 
around, and it was a cheap approach to try what we had on hand first =)

A good thing for you is that the Linux driver is one for most of the 
Epson chips (download the file, you will see this sd1d1xxxfb.c (or 
something like it) file, it depends on different includes for different 
chips, but other than that it is always the same driver.

>Has it got X-Window driver[s] or only frame-buffer support? If only framebuffer, then it means frame
>buffer X-window server. And this one is a bit slow AFAIK...
>  
>
The driver is fb only - I agree with you, if you are going to use X, you 
dont want to go with that. On the other hand, unlsee you want a lot of 
applications on the desk, ditching X would help you in maximizing CPU 
usage as you request below. Qt-E by Trolltech (Disclaimer: I am a 
fanatical Qt user) supports Fb graphics, so if you do not need anything 
besides a browser (Opera can also use Qt-E, and Konqueror can also link 
agains it, although I would not recommend that one yet), you can well do 
without X.

>FL> I believe the card is enough for browser operation, yes. I am not sure
>FL> about playing video beacuse I have not performance-checked it , and as 
>FL> you pointed out, it is unaccelerated.  It should be able to display 
>FL> whatever you throw at it though, so if you can do the MPEG decoding 
>FL> completely in software on the MPC side, you should be fine.
>
>Thanks for these invaluable insights...
>  
>
My pleasure to be of help =)

>FL> Do you work at Turk Telecom or are you just a customer ?
>
>Yeah, I am just a customer. I dont like using company e-mail. Because it is read by third party
>products :-)
>  
>
>If possible, we want to decrease microprocessor clock. Normally we
>do it in VIA Epia-500MHz and thinking in parallel with, it should be done under 533, or perhaps
>[..] 466, 400. I dont know. We will test it. Do you know anything about it?
>  
>
Hmm - testing is the only way you can come up with a figure. But 
removing X from the equation will certinly gain you some % of CPU 
availability, which you will need for the soft mpeg decoder. You also 
want to test that the buffer setup of the whole thing is designed 
correctly for the kind of response and thruput you will need... I have 
seen reports on the mailing list of people having trouble b/c of some 
crippleware used in bus implementations.

-Federico


-- 
_________________________________________
-- "'Problem' is a bleak word for challenge" - Richard Fish

Muad'Dib of Caladan (Federico L. Lucifredi)- Harvard University & BU
http://metcs.bu.edu/~lucifred

Re: MPC8272ADS and frame buffer

[Federico Lucifredi]

Bora Þahin wrote:

>Hello Federico,
>
>Thanks for the infos...
>
>FL> You also 
>FL> want to test that the buffer setup of the whole thing is designed 
>FL> correctly for the kind of response and thruput you will need... I have 
>FL> seen reports on the mailing list of people having trouble b/c of some 
>FL> crippleware used in bus implementations.
>
>I dont understand it exactly. May you able to explain it a bit clearly?
>
>Thanks for the infos...
>  
>
I meant that you have to stress-test the bus connection that you are 
going to use to whatever graphic hardware you
select - you cannot count on embedded hardware being bleeding-edge 
performance, and you are going to play 25 or 30 frames a second over 
that bus -- it is a lot of data, and you have bandwidth (hopefully not a 
problem with pci) and jitter (delay variance) constraints.

    -Federico

-- 
_________________________________________
-- "'Problem' is a bleak word for challenge" - Richard Fish

Muad'Dib of Caladan (Federico L. Lucifredi)- Harvard University & BU
http://metcs.bu.edu/~lucifred

Re: MPC8272ADS and frame buffer

[Federico Lucifredi]

Bora Þahin wrote:

>Hi Federico,
>
>FL> I meant that you have to stress-test the bus connection that you are
>FL> going to use to whatever graphic hardware you
>FL> select - you cannot count on embedded hardware being bleeding-edge 
>FL> performance, and you are going to play 25 or 30 frames a second over 
>FL> that bus -- it is a lot of data, and you have bandwidth (hopefully not a 
>FL> problem with pci) and jitter (delay variance) constraints.
>
>Sory for the late answer...
>
>I see you. In fact I know it but some blurry situations is matter. We use IBM-PPC. It has
>CoreConnect bus. I dont know implementation details of it but it has three different buses. One is
>PLB. This is for speedy ones. PCI bridge is in this bus also. AFAIK, data and addres bus of it is
>decoupled. Clock speed is also high. I think it also support burst mode. So in the light of these
>infos it seems enough. So PCI is enough, this one sholud be enough also.
>
>But as you said, we should take into consideration that these cpus and buses are embedded and at
>some points, may have clipped version of desktop brothers.
>
>  
>
Exactly. And even when the cpu is not clipped, the board might be (I am 
handling right now a fully complete Motorola MPC8272 based design, the 
chip supports PCI burst, the board design, however, does not).

-Federico

-- 
_________________________________________
-- "'Problem' is a bleak word for challenge" - Richard Fish

Muad'Dib of Caladan (Federico L. Lucifredi)- Harvard University & BU
http://metcs.bu.edu/~lucifred

Re: MPC8272ADS and frame buffer

[Federico Lucifredi]

Hello Bora,
 

> FL>     It turns out you can solve your problem by using the Epson 
> SD13806
> FL> evaluation board (s5u13806b00c).
>
> Has this evaboard got PCI interface?
>  
>
It is a PCI card form factor. The epson chip does NOT have a PCI 
interface on board, so a PCI bridge chip is there to support PCI 
operation -- In short, if you want to use PCI, it is available by 
activating it with a DIP switch.  I did use it, and it works.

> FL> It comes with drivers distributed, FL> inanely enough, as a patch 
> for a specific kernel, so prepare for some FL> hand-patching. Other 
> than that, it works.
>  
>

> We would like to use it with two purposes. One is to display 
> browser(Opera, Mozilla, Firefox or what
> it is) and second one is to play films encoded by mpeg. AFAIK, this 
> card is framebuffer style. It
> has some 2D acceleration mainly for blitting operations. I think films 
> are not drawing thing. Color
> space conversion, scaling are discussed. But others are drawing thing.
>
> Do you think this card is enought for them?
>  
>
I believe the card is enough for browser operation, yes. I am not sure 
about playing video beacuse I have not performance-checked it , and as 
you pointed out, it is unaccelerated.  It should be able to display 
whatever you throw at it though, so if you can do the MPEG decoding 
completely in software on the MPC side, you should be fine.

Do you work at Turk Telecom or are you just a customer ? What is your 
project, if I may ask ?

   -Federico

-- 
_________________________________________
-- "'Problem' is a bleak word for challenge" - Richard Fish

Muad'Dib of Caladan (Federico L. Lucifredi)- Harvard University & BU
http://metcs.bu.edu/~lucifred

MPC8272ADS and frame buffer

[Federico Lucifredi]

Hello Linux-PPCers,
    I have a quick one: I am looking at the Arabella kernel on the 
MPC8272ADS, which I am planning to use as a prototyping platform while 
we get to figure out a BSP for our custom board.

    Now, I have an Epson card on hand (13806) which I know to be working 
on ppc, and which has drivers as a kernel patch for 2.4.21, and I have a 
radeon card on hand which I used to like because of its vesa 2.0 
compliance.  The first brings up the problem of porting the patch to the 
2.4.26 kernel, which Arabella/Yuli Barcohen customized to the 
MPC8272ADS. The latter, according to Yuli himself, won't work because of 
BIOS initialization issues.

    I do not mind buying another card if necessary (time is at a greater 
premium), but I would like to know that there is a 2.4.6 driver for it 
or that it is supported by Arabella's kernel.

Anyone here using the Arabella BSP on the 8272ADS with a frame buffer on 
it ? What setup are you using?

-Federico