[U-Boot] [PATCH 0/4 V2] Add basic NVIDIA Tegra2 SoC support

[Tom Warren]

Wolfgang,

On Mon, Jan 17, 2011 at 4:27 PM, Wolfgang Denk <wd at denx.de> wrote:
> Dear Tom Warren,
>
> In message <AANLkTi=f-14JNam_DY5c1sGTT0nMqM-pNOk6gDg4d80d at mail.gmail.com> you wrote:
>>
>> 1) IO access functions - I pre-reviewed my patch series with Wolfgang
>> (to hopefully catch any blatant errors and smooth
>> the process) and he indicated that C structs and I/O accessor funcs or
>> macros were preferred to my base+offset original code.
>
> I don't think I said "preferred".
>
> I apologize if I really should have been unclear. Fact is, the use of
> I/O accessors is mandatory for any new code going in.
>
Sorry, I misunderstood what really constituted I/O accessors. Fixed in
V3 (coming soon).

>> Since the ARM is 32-bit, and all of our registers are I/O mapped, it
>> made sense just to cast the necessary HW mem-mapped
>> regs as volatile structs and access the members directly. Works well,
>> is easy to read & understand, etc. Let me know (with
>> examples, if possible) how I can make it better.
>
> It does NOT make sense. Please read the
> linux/Documentation/volatile-considered-harmful.txt document, and see
> recent dicussion in the "ARM: Avoid compiler optimization for usages
> of readb, writeb and friends." thread about what happens when you use
> just volatile pointers.
>
>> 2) Compiling out support for UARTA or UARTD - didn't seem necessary -
>> size isn't an issue at this point with Tegra2 U-Boot,
>
> Maybe you don't care, but we do.
>
> Please see http://www.denx.de/wiki/U-Boot/DesignPrinciples, item 5
>
Done in V3 patch.

>> I was going to respond to your review w/a direct, inline reply, but I
>> thought it better to get the V2 patch out there before the
>> weekend (we're off for MLK, as well). I'm under some pressure to get a
>> baseline Tegra2 patchset in before the merge window
>> closes.  I'll be sure to respond to each issue directly on the list in
>> the future, though.
>
> Please also make sure to maintain a changelog of in each of your
> patches (see second bullet in
> http://www.denx.de/wiki/view/U-Boot/Patches#Sending_updated_patch_versions).
>
OK. I added a V2/V3 changelog to each patch. Hope I got it right. New
patchset incoming.

>
>
>
> Best regards,
>
> Wolfgang Denk
Thanks for your patience,

Tom
>
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