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 <[email protected]> > --- > 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
