Re: [PATCH 3/6] arm64: tegra: Add Tegra210 support

[Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>]

On Fri, May 22, 2015 at 05:05:16PM +0200, Thierry Reding wrote:
> On Fri, May 22, 2015 at 02:38:00PM +0100, Catalin Marinas wrote:
> > So if you do it properly from the beginning with per-driver Kconfig
> > entry, I no longer see the point of an ARCH_TEGRA_*_SOC option. It may
> > be more convenient for people building end products but they should know
> > better what components are required, defconfig is rarely meant for them.
> 
> Your proposal also means that we'll have to go and add separate Kconfig
> entries for each SoC generation that a driver supports so that the SoC
> specific bits can be disabled.
> 
> So in order to get rid of one per-SoC Kconfig entry you'd prefer us to
> add per-SoC options per driver? Don't you think that's going to make
> things worse rather than improve them?
> 
> There are currently three drivers (off the top of my head) where we do
> this and each of them supports five existing generations plus the new
> Tegra210. So rather than having six symbols to select SoC generation
> support we'd be needing 18, and that's only counting existing drivers.

That's not what I meant. For example, you have a clk-tegra124.c file
built for two SoCs already and there may be more coming. Instead of
multiple obj-y of the same file, just add the entry below to
drivers/clk/tegra/Kconfig:

config CLK_TEGRA124
	bool "NVIDIA Tegra 124 clock"
	depends on ARCH_TEGRA_124_SOC || (ARM64 && ARCH_TEGRA)
	default y
	help
	  Used on Tegra 124, 132 etc.
	  ...

Note that I preserved the 124_SOC dependency for the 32-bit arm case.
But for arm64, just make it dependent on ARCH_TEGRA.

Once done, the Makefile only needs a single entry:

obj-$(CONFIG_TEGRA124) += clk-tegra124.o

-- 
Catalin