[U-Boot] When to create a SoC directory for ARM

[Scott Wood]

On Thu, 2013-09-26 at 13:46 -0700, York Sun wrote:
> On 09/26/2013 01:44 PM, Scott Wood wrote:
> > On Thu, 2013-09-26 at 12:57 -0700, York Sun wrote:
> >> On 09/26/2013 12:55 PM, Scott Wood wrote:
> >>> On Thu, 2013-09-26 at 12:48 -0700, York Sun wrote:
> >>>> On 09/26/2013 12:46 PM, Sharma Bhupesh-B45370 wrote:
> >>>>>
> >>>>>> -----Original Message-----
> >>>>>> From: u-boot-bounces at lists.denx.de [mailto:u-boot-bounces at lists.denx.de]
> >>>>>> On Behalf Of Scott Wood
> >>>>>> Sent: Friday, September 27, 2013 12:53 AM
> >>>>>> To: FengHua
> >>>>>> Cc: trini; sun york-R58495; u-boot
> >>>>>> Subject: Re: [U-Boot] When to create a SoC directory for ARM
> >>>>>>
> >>>>>> On Thu, 2013-09-26 at 13:23 +0800, FengHua wrote:
> >>>>>>> all SOC specific include file should be in
> >>>>>>> arch/arm/include/asm/arch-SOC/ or some common directory(like
> >>>>>>> include/asm/imx-common). Currently, u-boot only link SOC
> >>>>>>> specific(arch-SOC) include directory.
> >>>>>>> You could touch a mmu.h file in arch/arm/include/asm/arch-ls2/ and
> >>>>>>> include arch/arm/include/asm/arch-armv8/mmu.h.
> >>>>>>> or move arch-armv8/mmu.h to arch/arm/include/asm/ to make it as a
> >>>>>>> generic file.
> >>>>>>> Maybe we should distinguish architecture specific include directory
> >>>>>>> and SOC  specific include directory.
> >>>>>>
> >>>>>> Is the XXX arch-XXX supposed to be an SoC family or a CPU
> >>>>>> family/architectutre?
> >>>>>>
> >>>>>
> >>>>> Usually in 'arch/arm/include/asm' we have both:
> >>>>> - arch-armv7 (Arch specific. Houses stuff common to ARMv7 CPU, e.g. Global timer, SP805 WDT..)
> >>>>> - arch-mx6 (SoC family specific. Houses stuff like SoC specific IOMUX pads..)
> >>>
> >>> Which one does "#inculde <asm/arch/foo.h>" refer to?
> >>>
> >>
> >> arm/arch is a symbolic link created at compiling time. It points to
> >> arm/arch-$(soc), if $(soc) is not defined, then it points to
> >> asm/arch-$(arch). That's my understanding.
> > 
> > How is that supposed to work when both arch-$(soc) and arch-$(arch) are
> > present?  Why are SoC and CPU arch confused in this way?
> > 
> 
> It can't. That's why I am struggling. My temporary workaround is to
> include those headers in sub-arch headers.

My question is, more specifically, what is happening today on armv7
relative to this problem?

-Scott