Re: [PATCH 1/2] ARM: EXYNOS: Map SYSRAM through generic SRAM bindings

["Heiko Stübner" <heiko@sntech.de>]

Hi Sachin,

Am Donnerstag, 1. Mai 2014, 16:14:44 schrieb Sachin Kamat:
> Instead of hardcoding the SYSRAM details for each SoC,
> pass this information through device tree (DT) and make
> the code SoC agnostic. Generic SRAM bindings are used
> for achieving this.
> 
> Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
> Cc: Heiko Stuebner <heiko@sntech.de>
> Cc: Arnd Bergmann <arnd@arndb.de>

very cool :-).

I've found one little thing I do not understand, which I describe below. 
Otherwise
Acked-by: Heiko Stuebner <heiko@sntech.de>

> ---
> This patch is based on linux next (next-20140501) on top of
> my Kconfig consolidation patch
> http://comments.gmane.org/gmane.linux.kernel.samsung-soc/28642
> 
> Tested on 4210/4412 Origen, 5250/5420 Arndale and SMDK5420 boards.
> ---
>  arch/arm/Kconfig                                |    1 +
>  arch/arm/boot/dts/exynos4210-universal_c210.dts |   17 ++++++
>  arch/arm/boot/dts/exynos4210.dtsi               |   18 +++++++
>  arch/arm/boot/dts/exynos4x12.dtsi               |   18 +++++++
>  arch/arm/boot/dts/exynos5250.dtsi               |   18 +++++++
>  arch/arm/boot/dts/exynos5420.dtsi               |   18 +++++++
>  arch/arm/mach-exynos/common.h                   |    1 +
>  arch/arm/mach-exynos/exynos.c                   |   64
> ----------------------- arch/arm/mach-exynos/firmware.c                 |  
>  5 +-
>  arch/arm/mach-exynos/include/mach/map.h         |    7 ---
>  arch/arm/mach-exynos/platsmp.c                  |   39 +++++++++++++-
>  11 files changed, 133 insertions(+), 73 deletions(-)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index a6aaaad19b1a..f66ea9453df9 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -855,6 +855,7 @@ config ARCH_EXYNOS
>  	select S5P_DEV_MFC
>  	select SAMSUNG_DMADEV
>  	select SPARSE_IRQ
> +	select SRAM
>  	select USE_OF
>  	help
>  	  Support for SAMSUNG's EXYNOS SoCs (EXYNOS4/5)
> diff --git a/arch/arm/boot/dts/exynos4210-universal_c210.dts
> b/arch/arm/boot/dts/exynos4210-universal_c210.dts index
> 63e34b24b04f..8d4de5c0d0c7 100644
> --- a/arch/arm/boot/dts/exynos4210-universal_c210.dts
> +++ b/arch/arm/boot/dts/exynos4210-universal_c210.dts
> @@ -28,6 +28,23 @@
>  		bootargs = "console=ttySAC2,115200N8 root=/dev/mmcblk0p5 rw rootwait
> earlyprintk panic=5 maxcpus=1"; };
> 
> +	sram@02020000 {
> +		status = "disabled";
> +	};
> +
> +	sram@02025000 {
> +		compatible = "mmio-sram";
> +		reg = <0x02025000 0x1000>;
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		ranges = <0 0x02025000 0x1000>;
> +
> +		smp-sram@0 {
> +			compatible = "samsung,exynos4210-sram";
> +			reg = <0x0 0x1000>;
> +		};
> +	};

exynos_smp_prepare_sram returns -ENODEV if it can't find
samsung,exynos4210-sram-ns, so are you sure your universal_c210 will run 
without it? I didn't dig to deep into this, so it can also simply be something 
I overlooked :-)


Heiko