| Message ID | 1323757530-19402-3-git-send-email-richard.zhao@linaro.org |
|---|---|
| State | New |
| Headers | show |
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. > 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@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.
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@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@02100000 { /* AIPS2 */ > > + enet@02188000 { > > + phy-mode = "rgmii"; > > + phy-reset-gpios = <&gpio3 23 0>; > > + status = "okay"; > > + }; > > + > > + usdhc@02198000 { /* uSDHC3 */ > > + cd-gpios = <&gpio7 0 0>; > > + wp-gpios = <&gpio7 1 0>; > > + status = "okay"; > > + }; > > + > > + usdhc@0219c000 { /* uSDHC4 */ > > + cd-gpios = <&gpio2 6 0>; > > + wp-gpios = <&gpio2 7 0>; > > + status = "okay"; > > + }; > > + > > + uart1: uart@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 >
On Tue, Dec 13, 2011 at 08:54:01PM +0800, Richard Zhao wrote: > > > + cpus { > > > + cpu@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. > I understand all these things. What I was suggesting is this option should not be provided by the dts at all. For example, you have one sabrelite that can provide voltage for imx6q to run at 1GHz, while I have another sabrelite board which can only provide voltage for imx6q to run at 800MHz. With your patches accepted, the same mainline kernel/dtb will work on your sabrelite board while will not on mine. Since both of us are running sabrelite board, how do I should know I need to change the clock-frequency in imx6q-sabreauto.dts for my sabrelite board?
On Tue, Dec 13, 2011 at 09:33:50PM +0800, Shawn Guo wrote: > On Tue, Dec 13, 2011 at 08:54:01PM +0800, Richard Zhao wrote: > > > > + cpus { > > > > + cpu@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. > > > I understand all these things. What I was suggesting is this option > should not be provided by the dts at all. Yes. If it's not provided the cpufreq layer should either assume 800MHz is the highest value which is safe on all boards or it could read the current frequency from the hardware. If this is 1GHz this value is obviously safe. Sascha
On Wed, Dec 14, 2011 at 12:05:58PM +0100, Sascha Hauer wrote: > On Tue, Dec 13, 2011 at 09:33:50PM +0800, Shawn Guo wrote: > > On Tue, Dec 13, 2011 at 08:54:01PM +0800, Richard Zhao wrote: > > > > > + cpus { > > > > > + cpu@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. > > > > > I understand all these things. What I was suggesting is this option > > should not be provided by the dts at all. > > Yes. If it's not provided the cpufreq layer should either assume 800MHz > is the highest value which is safe on all boards or it could read the > current frequency from the hardware. If this is 1GHz this value is > obviously safe. Actually, you'd better not depend on uboot to setting the highest cpu freq. At least current freescale internel uboot don't set 1G. Thanks Richard > > Sascha > > > -- > Pengutronix e.K. | | > Industrial Linux Solutions | http://www.pengutronix.de/ | > Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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@0 { + clock-frequency = <996000000>; + }; + }; + + memory { + reg = <0x10000000 0x40000000>; + }; + + soc { + aips-bus@02100000 { /* AIPS2 */ + enet@02188000 { + phy-mode = "rgmii"; + phy-reset-gpios = <&gpio3 23 0>; + status = "okay"; + }; + + usdhc@02198000 { /* uSDHC3 */ + cd-gpios = <&gpio7 0 0>; + wp-gpios = <&gpio7 1 0>; + status = "okay"; + }; + + usdhc@0219c000 { /* uSDHC4 */ + cd-gpios = <&gpio2 6 0>; + wp-gpios = <&gpio2 7 0>; + status = "okay"; + }; + + uart1: uart@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, };
- 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