[Arm-netbook] AMD APU's in EOMA and ARM SOC's with PCIe

[lkcl luke]

On Sun, Jan 22, 2012 at 5:10 PM, Bari Ari <bari at onelabs.com> wrote:
> Since we can fit a dual core AMD APU + LPDDR3 + HUB into the EOMA68
> footprint what do we do with card edge pinouts? The EOMA68 can have the
> two extra power pins to support 10W but now we have the new options of
> PCIe, GB-Ethernet, HDMI, Displayport, DVI or VGA, HD audio, SPI and SATA.

 i've just gone and bloody well reorganised EOMA68 to cope with
gigabit ethernet argh! :)
 http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-68#Pinouts_.28Version_1.0.29

 argh, i wasn't anticipating to deal with this for another couple of
years, ah well.

 ok, SATA can still go on EOMA.  i've just updated to include gigabit
ethernet.  HDMI is DVI: both are 19 pins, that's too much - they can
go on the edge-connector.  VGA is irrelevant.  that leaves
displayport, PCIe, SPI and HD audio.

 SPI is 5 pins, that's manageable.  HD audio is 9??? ok, 8 if you
exclude the GND.  that's... a hell of a lot to dedicate to something
as "stoopid" as audio.  ok, you know what i mean: it's not a
general-purpose bus.

 right.

 i don't actually have enough experience with x86 CPUs to know what's
common across all the various chipsets.  is it normal for them to all
have displayport?  or, are the chipsets all different?  last time i
looked at intel atom - when i could find anything at all - they had
LVDS outputs.

 the important thing is that the EOMA-68 be for the *internal*
connectors.  anything that's normally an external connector, it should
stay that way.

> Do we make EOMA68 typeII 5mm cards for ARM only and have x86 be typeIII
> 10.5mm only with a new pinout?

 i'd kinda like them to be backwards-compatible.  why force
manufacturers to make 2 different types of chassis?

 or... hmmm... is it going to be pretty much impossible? i don't know.

> How about newer ARM SOC's with PCIe and HDMI and displayport,
> GB-Ethernet etc? Do we make them typeIII or?


 yeah.... nuts.  i'm coming round to the idea of having a 2nd
(incompatible) standard, for the faster interfaces.... wait....

 http://en.wikipedia.org/wiki/DisplayPort

 that's an _external_ interface.  and, come to think of it, so is HD audio.

 so those are out.

 that just leaves SPI, PCIe and something-to-connect-a-screen-to.
dual-LVDS?  single-lane MIPI?  is MIPI the same as DisplayPort?
http://en.wikipedia.org/wiki/Display_Serial_Interface doesn't look
like it.

 what's common across x86 and ARM SoCs for video out?  the exynos4210
has MIPI or RGB/TTL 24-pin: it *doesn't* have LVDS or DisplayPort.

 how many pins are needed for PCIe x1?
http://pinouts.ru/Slots/pci_express_pinout.shtml  i make it... 8.
2xtx, 2xrx, 2xclk, TRST# and WAKE# .  SMBus is effectively I2C, and
that's already being passed through.

l.