Re: [PATCH] misc: sram: extend usage of reserved partitions

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Aug 10, 2015 at 12:40:02AM +0300, Vladimir Zapolskiy wrote:
> This change adds functionality to operate on reserved SRAM partitions
> described in device tree file. Two partition properties are added,
> "pool" and "export", the first one allows to share a specific partition
> for usage by a kernel consumer in the same manner as it is done for
> the whole SRAM device, and "export" property provides access to some
> SRAM area from userspace over sysfs interface. Practically it is
> possible to specify both properties for an SRAM partition, however
> simultaneous access from a kernel consumer and from userspace is not
> serialized, but still the combination may be useful for debugging
> purpose.
> 
> Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
> ---
> To test SRAM partition export to userspace it might be sufficient
> to add an exported subnode, write data to created binary attribute file,
> do soft reboot and read the contents of the same binary attribute
> file. Aware of any potential use of SRAM by a bootloader etc.
> 
> To give an idea how to use "pool" partition feature here is an example
> for Freescale iMX6Q SabreAuto with CODA driver as a user:
> 
> arch/arm/boot/dts/imx6q.dtsi @@ -82,6 +82,10 @@
>  			compatible = "mmio-sram";
>  			reg = <0x00900000 0x40000>;
>  			clocks = <&clks IMX6QDL_CLK_OCRAM>;
> +
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			ranges = <0 0x00900000 0x40000>;
>  		};
>  
>  		aips-bus@02000000 { /* AIPS1 */
> arch/arm/boot/dts/imx6qdl-sabreauto.dtsi @@ -490,3 +490,18 @@
>  				0x0000c000 0x1404a38e 0x00000000>;
>  	};
>  };
> +
> +&ocram {
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +
> +	vpu_iram: vpu_iram {
> +		reg = <0x00008000 0x00021000>;
> +		pool;
> +	};
> +};
> +
> +&vpu {
> +	iram = <&vpu_iram>;
> +};
> 

Putting a diff in a patch changelog is tricky, do you really need it?

And why send 2 copies of this patch, what changed?

confused,

greg k-h