Messages in this thread | | | Date | Sun, 9 Oct 2011 14:21:35 +0800 | Subject | Re: [PATCH 17/26] ARM: pxa: pxa95x is incompatible with earlier pxa | From | Haojian Zhuang <> |
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On Sat, Oct 8, 2011 at 9:24 PM, Arnd Bergmann <arnd@arndb.de> wrote: > On Saturday 08 October 2011 11:32:14 Haojian Zhuang wrote: >> >> Eric, >> >> At first, a new macro (ARCH_PXA_V7) is defined in >> arch/arm/mach-pxa/Kconfig in this patch. >> I prefer to move this macro to arch/arm/Kconfig. > > If we move it to arch/arm/Kconfig, I would prefer making it a global option, > not a pxa specific one. If we introduce a top-level CONFIG_CPU_V6PLUS > option, we can make a number of decisions inside of Kconfig depend on that, > especially as we move to allow building multiple v6/v7 platforms together, > or multiple v5 platforms for that matter. I believe we don't need to > worry about v5+v7 at this point and can instead assume that won't ever > happen. > Nobody is using PJ4 as v6 architecture now. CPUv6 is used in old stepping of Dove and MMP2. CPU_PJ4 only enables CPU_v7 in the mainline code.
If we used ARCH_PXA_V7 in arch/arm/Kconfig, we would have two ARCH for pxa. One is ARCH_PXA, and the other is ARCH_PXA_V7. Those v5 machine should be based on ARCH_PXA. And the saarb, tavorevb3 should be based on ARCH_PXA_V7. So we can avoid to define PXA_V7_MACH_AUTO. I think the logic of Kconfig could be easier.
>> Secondly, pxa95x is both used in saarb and tavorevb3. > > The patch makes that very explicit, doesn't it? > +config PXA_V7_MACH_AUTO + def_bool y + depends on ARCH_PXA_V7 + depends on !MACH_SAARB + select MACH_TAVOREVB3 +
Please check this. In your patch, SAARB and TAVOREVB3 is a mutex.
>> Thirdly, PXA_V7_MACH_AUTO is unnecessary. We just need to select those >> machines in defconfig or define a new DT machine type to select all >> machines. > > Enabling them in defconfig will not help here, it still allows creating > an invalid configuration by disabling both saarb and tavorevb3. > I agree that it would be best to have a single DT machine type that can > handle both saarb and tavorevb3 as well as any future pxa95x based machines, > but nobody has implemented that yet. In the meantime, I think we should > have the PXA_V7_MACH_AUTO or an equivalent mechanism to enforce that at > least one of the two board files gets built into any kernel. This is mostly > important to help the 'make randconfig' builds succeed, not for actual > users getting it wrong accidentally. > > Arnd >
Exactly we need to define a single DT machine type in both arch-pxa and arch-mmp. I'll register it first.
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