Re: [PATCH 4/9] ARM: add CONFIG_PHYS_OFFSET default values

[Arnd Bergmann]

On Thursday 18 February 2016 11:02:33 Nicolas Pitre wrote:
> 
> Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>
> 
> Is there a way to provide a default for defaults?

We could have something like

config PHYS_OFFSET_0
	bool

config PHYS_OFFSET_1
	bool

config PHYS_OFFSET_2
	bool

... (we need 8 of the 16 possible addresses)


config PHYS_OFFSET
	hex "Physical address of main memory" if MMU
	default DRAM_BASE if !MMU
	default 0x00000000 if PHYS_OFFSET_0
	default 0x10000000 if PHYS_OFFSET_1
	default 0x20000000 if PHYS_OFFSET_2
	default 0x30000000 if PHYS_OFFSET_3
	default 0x70000000 if PHYS_OFFSET_7
	default 0x80000000 if PHYS_OFFSET_8
	default 0xa0000000 if PHYS_OFFSET_A
	default 0xc0000000 if PHYS_OFFSET_C


and then select one of the bool symbols from each platform.
Would that address your question?

FWIW, that would also let us do:

config XIP_KERNEL
	bool "Kernel Execute-In-Place from ROM"
	depends on PHYS_OFFSET_0 || PHYS_OFFSET_1 || PHYS_OFFSET_2 ||
		   PHYS_OFFSET_3 || PHYS_OFFSET_7 || PHYS_OFFSET_8 ||
		   PHYS_OFFSET_A || PHYS_OFFSET_C

We can probably come up with a more elaborate way to prevent configurations
that have more than one of these set.

	Arnd