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

[Catalin Marinas]

On Fri, May 15, 2015 at 12:19:16PM +0200, Thierry Reding wrote:
> On Wed, May 13, 2015 at 06:11:15PM +0100, Catalin Marinas wrote:
> > On Wed, May 13, 2015 at 04:57:42PM +0200, Thierry Reding wrote:
> > > From: Thierry Reding <treding at nvidia.com>
> > > 
> > > NVIDIA Tegra210 (also known as Tegra X1) has four Cortex-A57 and four
> > > Cortex-A53 CPUs. Compared to Tegra124 and Tegra132 it comes with a 256-
> > > core Maxwell GPU. It supports processing videos of up to 4K resolutions
> > > at 60 fps (H.265, VP9, H.264).
> > > 
> > > Signed-off-by: Thierry Reding <treding at nvidia.com>
> > > ---
> > >  arch/arm64/Kconfig                       |   9 +
> > >  arch/arm64/boot/dts/nvidia/tegra210.dtsi | 998 +++++++++++++++++++++++++++++++
> > >  2 files changed, 1007 insertions(+)
> > >  create mode 100644 arch/arm64/boot/dts/nvidia/tegra210.dtsi
> > > 
> > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > > index 7796af4b1d6f..bfdf064ada66 100644
> > > --- a/arch/arm64/Kconfig
> > > +++ b/arch/arm64/Kconfig
> > > @@ -225,6 +225,15 @@ config ARCH_TEGRA_132_SOC
> > >  	  but contains an NVIDIA Denver CPU complex in place of
> > >  	  Tegra124's "4+1" Cortex-A15 CPU complex.
> > >  
> > > +config ARCH_TEGRA_210_SOC
> > > +	bool "NVIDIA Tegra210 SoC"
> > > +	depends on ARCH_TEGRA
> > > +	select PINCTRL_TEGRA210
> > > +	select USB_ULPI if USB_PHY
> > > +	select USB_ULPI_VIEWPORT if USB_PHY
> > > +	help
> > > +	  Enable support for the NVIDIA Tegra210 SoC.
> > > +
> > 
> > The previous ARCH_TEGRA_132_SOC escaped me. Do we need all these
> > ARCH_TEGRA_*_SOC entries? Can we not have per-driver Kconfig options?
> > For example, ARCH_TEGRA_132_SOC seems to be only used in
> > drivers/clk/tegra, a specific Kconfig entry in there would suffice.
> 
> There are actually a couple of other places where this will be used in
> subsequent patches (e.g. memory controller driver). The idea behind
> having these is that each one of them is used to enable the essentials
> out of the box, so that people don't have to go and enable a bunch of
> driver-specific Kconfig options just to get a kernel configuration that
> can actually boot.

We debated whether to have ARCH_* options at all on arm64 and we settled
for the middle ground - only add them for SoC families, not individual
SoCs. As for the kernel configuration that actually boots, we want the
arm64 defconfig to include all the supported SoCs and drivers (though
longer term I'd like to see more drivers built as modules by default).

> This is also useful for integrators since they can simply omit all SoC
> generations that they're not interested in. Having a per-SoC option
> provides an easy way of doing so.

The integrators could just select a SoC family and trim down unwanted
options, I don't think they rely on the kernel defconfig for a final
product. If this becomes an issue, I would rather have per-SoC
defconfigs than lots of Kconfig entries.

-- 
Catalin