[U-Boot] [PATCH] tegra30: fix UART2 pinmux table entry

[Stephen Warren]

On 01/09/2013 10:58 AM, Allen Martin wrote:
> On Tue, Jan 08, 2013 at 07:46:03PM -0800, Stephen Warren wrote:
>> On 01/08/2013 06:23 PM, Allen Martin wrote:
>>> UART2_TXD and UART2_RXD mux 0 SFIO entries should be IRDA not UARTB.
>>
>> IRDA is just a needlessly different synonym for UARTB; there shouldn't
>> be any mention of IRDA in the pinmux code anywhere, or any users of the
>> pinmux code.
> 
> Oh suck, I didn't realize we had synonyms in the pinmux tables, that
> seems like a really bad idea.  Unfortunately it looks like this
> particular synonym is widespread.  I see it used in the pinmux
> spreadsheets, the downstream Android kernel source, and gfshell code.

It will disappear from the downstream kernels once they've picked up the
upstream pinctrl driver; I spent a fair bit of time correlating all the
various documentation sources and eliminating duplicate names for the
upstream kernel pinctrl driver.

> The bug I was trying to fix here is that IRDA is referenced in the
> u-boot cardhu pinmux table.

Oh, I didn't notice that the second time round; I'm pretty sure I
pointed it out in the very first review. Maybe that was just of the
U-Boot pinmux driver and not the Cardhu file.

> I guess the fix is to change that to
> UARTB, but it sounds like maybe a larger synonym cleanup is needed
> everywhere, do you know of any others? 

I can't recall for sure; I think there were some. I'd suggest comparing
upstream U-Boot's pinmux driver with the upstream kernel's pinctrl
driver, treating the kernel as canonical now.

> I'm thinking there needs to be some better run time error checking in
> the u-boot pinmux code too.  There are some debug asserts in there
> now, but because I didn't have debug turned on this particular bug
> lead to silent corruption of the pinmux registers which was a PITA to
> track down.  Thoughts on turning those asserts into always on error
> checking code?  Not sure how much it will slow down pinmux programming.

I doubt the speed would be significantly affected, unless an error
triggers and the printf/... actually happens, but you don't really care
about speed then.