[PATCH V2 2/7] arm/imx6: add imx6q sabrelite board support

[richard.zhao@linaro.org (Richard Zhao)]

Hi Shawn,
On Tue, Dec 13, 2011 at 07:56:55PM +0800, Shawn Guo wrote:
> On Tue, Dec 13, 2011 at 02:25:25PM +0800, Richard Zhao wrote:
> > - Add basic board dts file
> > - Add board compatible string to mach-imx6q.
> > 
> > Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
> > ---
> >  arch/arm/boot/dts/imx6q-sabrelite.dts |   55 +++++++++++++++++++++++++++++++++
> >  arch/arm/mach-imx/mach-imx6q.c        |    1 +
> >  2 files changed, 56 insertions(+), 0 deletions(-)
> >  create mode 100644 arch/arm/boot/dts/imx6q-sabrelite.dts
> > 
> 
> Documentation/devicetree/bindings/arm/fsl.txt needs to be updated to
> include compatible string for this sabrelite board.
ah, thanks.
> 
> > diff --git a/arch/arm/boot/dts/imx6q-sabrelite.dts b/arch/arm/boot/dts/imx6q-sabrelite.dts
> > new file mode 100644
> > index 0000000..381f030
> > --- /dev/null
> > +++ b/arch/arm/boot/dts/imx6q-sabrelite.dts
> > @@ -0,0 +1,55 @@
> > +/*
> > + * Copyright 2011 Freescale Semiconductor, Inc.
> > + * Copyright 2011 Linaro Ltd.
> > + *
> > + * The code contained herein is licensed under the GNU General Public
> > + * License. You may obtain a copy of the GNU General Public License
> > + * Version 2 or later at the following locations:
> > + *
> > + * http://www.opensource.org/licenses/gpl-license.html
> > + * http://www.gnu.org/copyleft/gpl.html
> > + */
> > +
> > +/dts-v1/;
> > +/include/ "imx6q.dtsi"
> > +
> > +/ {
> > +	model = "Freescale i.MX6 Quad SABRE Lite Board";
> > +	compatible = "fsl,imx6q-sabrelite", "fsl,imx6q";
> > +
> > +	cpus {
> > +		cpu at 0 {
> > +			clock-frequency = <996000000>;
> > +		};
> 
> I do not follow why we need to have cpu frequency encoded in board
> level dts.  To me, what frequency the cpu is capable of running at
> is really soc specific thing.  So putting this data in
> imx6q-sabrelite.dts is kinda suggesting that imx6q soc on this
> sabrelite board can run at 996000000, while on other boards like
> sabreauto/arm2 can only run at other frequency.  This is seems different
> from what I heard from Freescale internal development team.
1G operation needs a certain external voltage condition, though we have
internal regulater. Boards that don't meet the condition have to fall back
to lower frequency.
>From software side view, I refer to Freescale software release. please see
http://opensource.freescale.com/git?p=imx/linux-2.6-imx.git;a=blob;f=arch/arm/mach-mx6/cpu_op-mx6.c;h=30a4346282ea5c332b4c48bf6a2d644abd9f31db;hb=imx_2.6.38_11.11.01

and for imx53, there' also different max freq board:
http://opensource.freescale.com/git?p=imx/linux-2.6-imx.git;a=blob;f=arch/arm/mach-mx5/mx53_wp.c;h=a63bae42fb661c161cab99d61f4a3108305b0f55;hb=refs/heads/imx_2.6.35_11.09.01

IMHO, even the board has limitations, we'd better give an option to support
it if it's possible.

Thanks
Richard

> 
> -- 
> Regards,
> Shawn
> 
> > +	};
> > +
> > +	memory {
> > +		reg = <0x10000000 0x40000000>;
> > +	};
> > +
> > +	soc {
> > +		aips-bus at 02100000 { /* AIPS2 */
> > +			enet at 02188000 {
> > +				phy-mode = "rgmii";
> > +				phy-reset-gpios = <&gpio3 23 0>;
> > +				status = "okay";
> > +			};
> > +
> > +			usdhc at 02198000 { /* uSDHC3 */
> > +				cd-gpios = <&gpio7 0 0>;
> > +				wp-gpios = <&gpio7 1 0>;
> > +				status = "okay";
> > +			};
> > +
> > +			usdhc at 0219c000 { /* uSDHC4 */
> > +				cd-gpios = <&gpio2 6 0>;
> > +				wp-gpios = <&gpio2 7 0>;
> > +				status = "okay";
> > +			};
> > +
> > +			uart1: uart at 021e8000 { /* UART2 */
> > +				status = "okay";
> > +			};
> > +		};
> > +	};
> > +};
> > diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
> > index 8deb012..d24d6c4 100644
> > --- a/arch/arm/mach-imx/mach-imx6q.c
> > +++ b/arch/arm/mach-imx/mach-imx6q.c
> > @@ -73,6 +73,7 @@ static struct sys_timer imx6q_timer = {
> >  
> >  static const char *imx6q_dt_compat[] __initdata = {
> >  	"fsl,imx6q-sabreauto",
> > +	"fsl,imx6q-sabrelite",
> >  	NULL,
> >  };
> >  
> > -- 
> > 1.7.5.4
>