On 01/25/2013 01:49 PM, Simon Glass wrote:
Hi Lucas,
On Sat, Jan 26, 2013 at 10:38 AM, Lucas Stach dev@lynxeye.de wrote:
Hello Simon,
Am Samstag, den 26.01.2013, 10:20 +1300 schrieb Simon Glass:
Hi Lucas,
On Fri, Jan 25, 2013 at 7:22 AM, Lucas Stach dev@lynxeye.de wrote:
Am Freitag, den 25.01.2013, 06:54 +1300 schrieb Simon Glass:
Hi Lucas,
On Fri, Jan 25, 2013 at 5:48 AM, Lucas Stach dev@lynxeye.de wrote:
Init pinmux in one shot, in order to avoid any conflicts.
Signed-off-by: Lucas Stach dev@lynxeye.de
board/nvidia/seaboard/seaboard.c | 133 +++++++++++++++++++++++++++++++++------ include/configs/seaboard.h | 3 + include/configs/ventana.h | 3 + 3 files changed, 121 insertions(+), 18 deletions(-)
This seems like a lot of code and presumably quite a bit of duplication between boards. What sort of conflicts does this avoid, and is it the only way of avoiding them?
I don't see it as duplication, but as explicitly spelling out how the pinmux configuration should be set up on a certain board.
I mean that the table is very similar for different boards, so looks like duplicated coded (133 very similar lines for each board).
Also, this seems to break FDT use. At present it is possible (I think) to boot the same U-Boot on any board, with the device tree specifying the config. With your change that is no longer possible, I think?
Looking ahead to T114 I see a similar problem. The funcmux approach was a compromise in that we could just select appropriate values for each function - there was no agreement on how to put this in the FDT though (my intention was that it would depend on the kernel binding, but that is now defined, so what excuse do we have for not implementing it in U-Boot?).
That Tegra30 doesn't do so either. ;) But I agree, that's no valid excuse and we should resolve this before Tegra114 introduces more of this stuff. See below.
Before this change we would leave some pads uninitialised in their (random) reset configuration. For example on the Colibri this leads to NAND not working as it's wired up to the KBC pads. If we only configure those, ATC will remain in it's reset state and would be also configured to the NAND function, which leads to fail. Having an explicit, known to be conflict free configuration for all pads avoids all those unpleasant surprises.
Well yes, but we seem to be right back to where we started, with the FDT unable to describe a key feature of the boards (pinmux).
I see your point now. The obvious answer for now is: it's not regressing functionality, as we were never able to boot the same U-Boot image by just changing the DT.
Well, kind of. In fact we were able to boot at 3 different T20 boards just by adding a 'funcmux' property to the device's node to select the required mux option for that driver. This code is no use on T30/T114, and was only a stop-gap anyway.
??? I don't believe U-Boot supports any "funcmux" property in the device tree. Are you referring to some downstream U-Boot? Such a branch wouldn't be relevant to a patch for upstream U-Boot.