Regarding irq_of_parse_and_map

Regarding irq_of_parse_and_map

[Vijay Nikam]

Hello All,

I have mpc8313erdb evaluation board and writing GPIO driver for it. I
know that it is not possible to use directly hardware_irq_number given
from the processor manual. In my case hardware _irq_number is 74 (for
GPIO). As request_irq uses the virtual irq.

So to know or determine what virtual irq it gives I tried with
irq_create_mapping and passed host = NULL and hwirq = 74.

virt_irq = irq_create_mapping (NULL, 74);

the value it gives me is the same as hwirq no. i.e. 74. also the
module is inserted properly and the GPIO is toggling.

1. Here I would like to ask is the way I have done is right ? ? ?
especially the host parameter I have set to NULL; as in this case it
uses default controller, so I chose to use NULL.

2. Also I would like to ask how I can determine the virtual irq using
irq_of_parse_and_map (struct device_node *dev, int index)  ? ? ?

here I am not getting what I should pass *dev and index ? ? ? as in my
mpc8313erdb.dts I could not find any node name 'gpio' so I do not know
what I can use ...

Kindly please acknowledge ... thank you ...

Following is the content of mpc8313erdb.dts
###################### Start #############################
/*
 * MPC8313E RDB Device Tree Source  */
/ {
	model = "MPC8313ERDB";
	compatible = "mpc83xx";
	#address-cells = <1>;
	#size-cells = <1>;

	cpus {
		#cpus = <1>;
		#address-cells = <1>;
		#size-cells = <0>;

		PowerPC,8313@0 {
			device_type = "cpu";
			reg = <0>;
			d-cache-line-size = <20>;	// 32 bytes
			i-cache-line-size = <20>;	// 32 bytes
			d-cache-size = <4000>;		// L1, 16K
			i-cache-size = <4000>;		// L1, 16K
			timebase-frequency = <0>;	// from bootloader
			bus-frequency = <0>;		// from bootloader
			clock-frequency = <0>;		// from bootloader
			32-bit;
		};
	};

	memory {
		device_type = "memory";
		reg = <00000000 08000000>;	// 128MB at 0
	};

	nand0 {
		device_type = "nand";
		compatible = "fsl-nand";
		linux,phandle = <301>;
		reg = <e2800000 2000>;
		/*partitions = "nand0:1m(u-boot)ro,3m(kernel),-(jffs2)";*/
	};

	soc8313@e0000000 {
		#address-cells = <1>;
		#size-cells = <1>;
		#interrupt-cells = <2>;
		device_type = "soc";
		ranges = <0 e0000000 00100000>;
		reg = <e0000000 00000200>;
		bus-frequency = <0>;

		wdt@200 {
			device_type = "watchdog";
			compatible = "mpc83xx_wdt";
			reg = <200 100>;
		};

		i2c@3000 {
			device_type = "i2c";
			compatible = "fsl-i2c";
			reg = <3000 100>;
			interrupts = <e 8>;
			interrupt-parent = <700>;
			dfsrr;
		};

		i2c@3100 {
			device_type = "i2c";
			compatible = "fsl-i2c";
			reg = <3100 100>;
			interrupts = <f 8>;
			interrupt-parent = <700>;
			dfsrr;
		};

		spi@7000 {
			device_type = "spi";
			compatible = "mpc83xx_spi";
			reg = <7000 1000>;
			interrupts = <10 8>;
			interrupt-parent = <700>;
			mode = <0>;
		};

		/* phy type (ULPI, UTMI, UTMI_WIDE, SERIAL) */
		usb@23000 {
			device_type = "usb";
			compatible = "fsl-usb2-dr";
			reg = <23000 1000>;
			#address-cells = <1>;
			#size-cells = <0>;
			interrupt-parent = <700>;
			interrupts = <26 2>;
			phy_type = "utmi_wide";
			control_init  = <00000280>; // UTMI ext 48 MHz clk
			sleep = <b00 00300000>;
		};

		mdio@24520 {
			device_type = "mdio";
			compatible = "gianfar";
			reg = <24520 20>;
			#address-cells = <1>;
			#size-cells = <0>;
			linux,phandle = <24520>;
			ethernet-phy@1 {
				linux,phandle = <2452001>;
				interrupt-parent = <700>;
				interrupts = <13 2>;
				reg = <1>;
				device_type = "ethernet-phy";
			};
			ethernet-phy@4 {
				linux,phandle = <2452004>;
				interrupt-parent = <700>;
				interrupts = <14 2>;
				reg = <4>;
				device_type = "ethernet-phy";
			};
		};

		ethernet@24000 {
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <24000 1000>;
			regs_1588 = <24000 24fff>;
			address = [ 00 00 00 00 00 00 ];
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <25 8 24 8 23 8>;
			interrupt-parent = <700>;
			phy-handle = <2452001>;
			sleep = <b00 20000000>;
			fsl,magic-packet;
		};

		ethernet@25000 {
			#address-cells = <1>;
			#size-cells = <0>;
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <25000 1000>;
			regs_1588 = <24000 24fff>;
			address = [ 00 00 00 00 00 00 ];
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <22 8 21 8 20 8>;
			interrupt-parent = <700>;
			phy-handle = <2452004>;
			sleep = <b00 10000000>;
			fsl,magic-packet;
		};

		serial@4500 {
			device_type = "serial";
			compatible = "ns16550";
			reg = <4500 100>;
			clock-frequency = <0>;
			interrupts = <9 8>;
			interrupt-parent = <700>;
		};

		serial@4600 {
			device_type = "serial";
			compatible = "ns16550";
			reg = <4600 100>;
			clock-frequency = <0>;
			interrupts = <a 8>;
			interrupt-parent = <700>;
		};

		pci@8500 {
			interrupt-map-mask = <f800 0 0 7>;
			interrupt-map = <

					/* IDSEL 0x0E -mini PCI */
					 7000 0 0 1 700 12 8
					 7000 0 0 2 700 12 8
					 7000 0 0 3 700 12 8
					 7000 0 0 4 700 12 8

					/* IDSEL 0x0F - PCI slot */
					 7800 0 0 1 700 11 8
					 7800 0 0 2 700 12 8
					 7800 0 0 3 700 11 8
					 7800 0 0 4 700 12 8>;
			interrupt-parent = <700>;
			interrupts = <42 8>;
			bus-range = <0 0>;
			ranges = <02000000 0 90000000 90000000 0 10000000
			          42000000 0 80000000 80000000 0 10000000
			          01000000 0 00000000 e2000000 0 00100000>;
			clock-frequency = <3f940aa>;
			#interrupt-cells = <1>;
			#size-cells = <2>;
			#address-cells = <3>;
			reg = <8500 100>;
			compatible = "83xx";
			device_type = "pci";
			sleep = <b00 00010000>;
		};

		/* May need to remove if on a part without crypto engine */
		crypto@30000 {
			device_type = "crypto";
			model = "SEC2";
			compatible = "talitos";
			reg = <30000 10000>;
			interrupts = <b 8>;
			interrupt-parent = <700>;
			num-channels = <4>;
			channel-fifo-len = <18>;
			exec-units-mask = <0000007e>;
			/* desc mask is for rev2.0,
			 * we need runtime fixup for >2.0 */
			descriptor-types-mask = <01010ebf>;
			sleep = <b00 03000000>;
		};

		/* IPIC
		 * interrupts cell = <intr #, sense>
		 * sense values match linux IORESOURCE_IRQ_* defines:
		 * sense == 8: Level, low assertion
		 * sense == 2: Edge, high-to-low change
		 */
		pic@700 {
			linux,phandle = <700>;
			interrupt-controller;
			#address-cells = <0>;
			#interrupt-cells = <2>;
			reg = <700 100>;
			built-in;
			device_type = "ipic";
		};

		elbc@5000 {
			linux,phandle = <5000>;
			device_type = "elbc";
			compatible = "fsl-elbc";
			reg = <5000 1000>;
			interrupts = <4d 8>;
			interrupt-parent = <700>;
		};

		power@b00 {
			linux,phandle = <b00>;
			device_type = "power";
			compatible = "fsl,mpc831x-pmc", "fsl,mpc83xx-pmc";
			reg = <b00 100
				a00 100>;
			interrupts = <50 8>;
			interrupt-parent = <700>;
		};

		timer@500 {
			linux,phandle = <500>;
			device_type = "timer";
			compatible = "fsl,mpc831x-gtm", "fsl,mpc83xx-gtm";
			reg = <500 100>;
			interrupts = <48 8>;
			interrupt-parent = <700>;
		};
	};
};


Kind Regards,
Vijay Nikam

Re: Regarding irq_of_parse_and_map

[Scott Wood]

On Mon, Feb 16, 2009 at 05:25:23PM +0530, Vijay Nikam wrote:
> 2. Also I would like to ask how I can determine the virtual irq using
> irq_of_parse_and_map (struct device_node *dev, int index)  ? ? ?
> 
> here I am not getting what I should pass *dev and index ? ? ? as in my
> mpc8313erdb.dts I could not find any node name 'gpio' so I do not know
> what I can use ...

You'd need to add a gpio node to the device tree.  If you do this, be
sure to follow existing bindings.

> 
> Kindly please acknowledge ... thank you ...
> 
> Following is the content of mpc8313erdb.dts

That device tree looks very old, as if it came from a BSP rather than
upstream Linux.

-Scott

Re: Regarding irq_of_parse_and_map

[Vijay Nikam]

I added the gpio node as follows to mpc8313erdb.dts;

gpio@c00 {
	linux,phandle = <c00>;
	device_type = "gpio";
	compatible = "";
	reg = <c00 100>;
	interrupts = <4a 8>;
	interrupt-parent = <700>;
	};

The only thing I need to know what should I write at 'compatible' tag
? ? ? the compatible tag format is "manufacturer,model" the
manufacturer is 'fsl' i.e. I think freescale but the model, as it is
the model number where I can find this model ? ? ? Please let me know
... thanks ...

Also I would like to ask if the above device node is written according
to bindings ... I think it should be right as I referred
'bootingwithout-of.txt' ... but please correct me if I am worng ? ? ?

If yes then I would like to confirm my further action is to compile
with dtc and create dtb and load it on the target and boot the board
... Am I Right ? ? ?

Kindly please acknowledge ... thank you ...

Following is the content of mpc8313erdb.dts to make it sure if it is
in bindings ...
################### DTS ##############################
/* MPC8313E RDB Device Tree Source */

/ {
	model = "MPC8313ERDB";
	compatible = "mpc83xx";
	#address-cells = <1>;
	#size-cells = <1>;

	cpus {
		#cpus = <1>;
		#address-cells = <1>;
		#size-cells = <0>;

		PowerPC,8313@0 {
			device_type = "cpu";
			reg = <0>;
			d-cache-line-size = <20>;	// 32 bytes
			i-cache-line-size = <20>;	// 32 bytes
			d-cache-size = <4000>;		// L1, 16K
			i-cache-size = <4000>;		// L1, 16K
			timebase-frequency = <0>;	// from bootloader
			bus-frequency = <0>;		// from bootloader
			clock-frequency = <0>;		// from bootloader
			32-bit;
		};
	};

	memory {
		device_type = "memory";
		reg = <00000000 08000000>;	// 128MB at 0
	};

	nand0 {
		device_type = "nand";
		compatible = "fsl-nand";
		linux,phandle = <301>;
		reg = <e2800000 2000>;
		/*partitions = "nand0:1m(u-boot)ro,3m(kernel),-(jffs2)";*/
	};

	soc8313@e0000000 {
		#address-cells = <1>;
		#size-cells = <1>;
		#interrupt-cells = <2>;
		device_type = "soc";
		ranges = <0 e0000000 00100000>;
		reg = <e0000000 00000200>;
		bus-frequency = <0>;

		wdt@200 {
			device_type = "watchdog";
			compatible = "mpc83xx_wdt";
			reg = <200 100>;
		};

		i2c@3000 {
			device_type = "i2c";
			compatible = "fsl-i2c";
			reg = <3000 100>;
			interrupts = <e 8>;
			interrupt-parent = <700>;
			dfsrr;
		};

		i2c@3100 {
			device_type = "i2c";
			compatible = "fsl-i2c";
			reg = <3100 100>;
			interrupts = <f 8>;
			interrupt-parent = <700>;
			dfsrr;
		};

		spi@7000 {
			device_type = "spi";
			compatible = "mpc83xx_spi";
			reg = <7000 1000>;
			interrupts = <10 8>;
			interrupt-parent = <700>;
			mode = <0>;
		};

		/* phy type (ULPI, UTMI, UTMI_WIDE, SERIAL) */
		usb@23000 {
			device_type = "usb";
			compatible = "fsl-usb2-dr";
			reg = <23000 1000>;
			#address-cells = <1>;
			#size-cells = <0>;
			interrupt-parent = <700>;
			interrupts = <26 2>;
			phy_type = "utmi_wide";
			control_init  = <00000280>; // UTMI ext 48 MHz clk
			sleep = <b00 00300000>;
		};

		mdio@24520 {
			device_type = "mdio";
			compatible = "gianfar";
			reg = <24520 20>;
			#address-cells = <1>;
			#size-cells = <0>;
			linux,phandle = <24520>;
			ethernet-phy@1 {
				linux,phandle = <2452001>;
				interrupt-parent = <700>;
				interrupts = <13 2>;
				reg = <1>;
				device_type = "ethernet-phy";
			};
			ethernet-phy@4 {
				linux,phandle = <2452004>;
				interrupt-parent = <700>;
				interrupts = <14 2>;
				reg = <4>;
				device_type = "ethernet-phy";
			};
		};

		ethernet@24000 {
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <24000 1000>;
			regs_1588 = <24000 24fff>;
			address = [ 00 00 00 00 00 00 ];
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <25 8 24 8 23 8>;
			interrupt-parent = <700>;
			phy-handle = <2452001>;
			sleep = <b00 20000000>;
			fsl,magic-packet;
		};

		ethernet@25000 {
			#address-cells = <1>;
			#size-cells = <0>;
			device_type = "network";
			model = "eTSEC";
			compatible = "gianfar";
			reg = <25000 1000>;
			regs_1588 = <24000 24fff>;
			address = [ 00 00 00 00 00 00 ];
			local-mac-address = [ 00 00 00 00 00 00 ];
			interrupts = <22 8 21 8 20 8>;
			interrupt-parent = <700>;
			phy-handle = <2452004>;
			sleep = <b00 10000000>;
			fsl,magic-packet;
		};

		serial@4500 {
			device_type = "serial";
			compatible = "ns16550";
			reg = <4500 100>;
			clock-frequency = <0>;
			interrupts = <9 8>;
			interrupt-parent = <700>;
		};

		serial@4600 {
			device_type = "serial";
			compatible = "ns16550";
			reg = <4600 100>;
			clock-frequency = <0>;
			interrupts = <a 8>;
			interrupt-parent = <700>;
		};

		pci@8500 {
			interrupt-map-mask = <f800 0 0 7>;
			interrupt-map = <

					/* IDSEL 0x0E -mini PCI */
					 7000 0 0 1 700 12 8
					 7000 0 0 2 700 12 8
					 7000 0 0 3 700 12 8
					 7000 0 0 4 700 12 8

					/* IDSEL 0x0F - PCI slot */
					 7800 0 0 1 700 11 8
					 7800 0 0 2 700 12 8
					 7800 0 0 3 700 11 8
					 7800 0 0 4 700 12 8>;
			interrupt-parent = <700>;
			interrupts = <42 8>;
			bus-range = <0 0>;
			ranges = <02000000 0 90000000 90000000 0 10000000
			          42000000 0 80000000 80000000 0 10000000
			          01000000 0 00000000 e2000000 0 00100000>;
			clock-frequency = <3f940aa>;
			#interrupt-cells = <1>;
			#size-cells = <2>;
			#address-cells = <3>;
			reg = <8500 100>;
			compatible = "83xx";
			device_type = "pci";
			sleep = <b00 00010000>;
		};

		/* May need to remove if on a part without crypto engine */
		crypto@30000 {
			device_type = "crypto";
			model = "SEC2";
			compatible = "talitos";
			reg = <30000 10000>;
			interrupts = <b 8>;
			interrupt-parent = <700>;
			num-channels = <4>;
			channel-fifo-len = <18>;
			exec-units-mask = <0000007e>;
			/* desc mask is for rev2.0,
			 * we need runtime fixup for >2.0 */
			descriptor-types-mask = <01010ebf>;
			sleep = <b00 03000000>;
		};

		/* IPIC
		 * interrupts cell = <intr #, sense>
		 * sense values match linux IORESOURCE_IRQ_* defines:
		 * sense == 8: Level, low assertion
		 * sense == 2: Edge, high-to-low change
		 */
		pic@700 {
			linux,phandle = <700>;
			interrupt-controller;
			#address-cells = <0>;
			#interrupt-cells = <2>;
			reg = <700 100>;
			built-in;
			device_type = "ipic";
		};

		elbc@5000 {
			linux,phandle = <5000>;
			device_type = "elbc";
			compatible = "fsl-elbc";
			reg = <5000 1000>;
			interrupts = <4d 8>;
			interrupt-parent = <700>;
		};

		power@b00 {
			linux,phandle = <b00>;
			device_type = "power";
			compatible = "fsl,mpc831x-pmc", "fsl,mpc83xx-pmc";
			reg = <b00 100
				a00 100>;
			interrupts = <50 8>;
			interrupt-parent = <700>;
		};

		timer@500 {
			linux,phandle = <500>;
			device_type = "timer";
			compatible = "fsl,mpc831x-gtm", "fsl,mpc83xx-gtm";
			reg = <500 100>;
			interrupts = <48 8>;
			interrupt-parent = <700>;
		};
	};
};
###################### END #######################################

Kind Regards,
Vijay Nikam

On 2/16/09, Scott Wood <scottwood@freescale.com> wrote:
> On Mon, Feb 16, 2009 at 05:25:23PM +0530, Vijay Nikam wrote:
> > 2. Also I would like to ask how I can determine the virtual irq using
> > irq_of_parse_and_map (struct device_node *dev, int index)  ? ? ?
> >
> > here I am not getting what I should pass *dev and index ? ? ? as in my
> > mpc8313erdb.dts I could not find any node name 'gpio' so I do not know
> > what I can use ...
>
> You'd need to add a gpio node to the device tree.  If you do this, be
> sure to follow existing bindings.
>
> >
> > Kindly please acknowledge ... thank you ...
> >
> > Following is the content of mpc8313erdb.dts
>
> That device tree looks very old, as if it came from a BSP rather than
> upstream Linux.
>
> -Scott
>

Re: Regarding irq_of_parse_and_map

[Scott Wood]

Vijay Nikam wrote:
> I added the gpio node as follows to mpc8313erdb.dts;
> 
> gpio@c00 {
> 	linux,phandle = <c00>;

Don't specify this explicitly.  Please base new development off of the 
device tree that is in upstream Linux, not the very old tree in your BSP.

> 	device_type = "gpio";

No device_type.

> The only thing I need to know what should I write at 'compatible' tag
> ? ? ? the compatible tag format is "manufacturer,model" the
> manufacturer is 'fsl' i.e. I think freescale but the model, as it is
> the model number where I can find this model ? ? ? Please let me know
> ... thanks ...

compatible = "fsl,mpc8313-gpio", "fsl,mpc8349-gpio";

> Also I would like to ask if the above device node is written according
> to bindings ... I think it should be right as I referred
> 'bootingwithout-of.txt' ... but please correct me if I am worng ? ? ?

See also Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt.

Also note that current Linux has a driver in 
arch/powerpc/sysdev/mpc8xxx_gpio.c.

-Scott

Re: Regarding irq_of_parse_and_map

[Vijay Nikam]

I checked and read the
Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt and
booting-without-of.txt. It is different then what I read before from
booting-without-of.txt ... perhaps as it is old and came with BSP. Am
I right ? ? ?

> Don't specify this explicitly.  Please base new development off of the
> device tree that is in upstream Linux, not the very old tree in your BSP.

May I know the reason why I should not specify it explicitly ? ? ?
Also what would be the problem if I do in the same way as it is given
in BSP mpc8313erdb.dts ? ? ?

And should I use gpio-controller as a gpio device node ? ? ?

Kindly please acknowledge ... thank you ...

Kind Regards,
Vijay Nikam

On 2/17/09, Scott Wood <scottwood@freescale.com> wrote:
> Vijay Nikam wrote:
> > I added the gpio node as follows to mpc8313erdb.dts;
> >
> > gpio@c00 {
> >        linux,phandle = <c00>;
> >
>
> Don't specify this explicitly.  Please base new development off of the
> device tree that is in upstream Linux, not the very old tree in your BSP.
>
> >        device_type = "gpio";
> >
>
> No device_type.
>
> > The only thing I need to know what should I write at 'compatible' tag
> > ? ? ? the compatible tag format is "manufacturer,model" the
> > manufacturer is 'fsl' i.e. I think freescale but the model, as it is
> > the model number where I can find this model ? ? ? Please let me know
> > ... thanks ...
> >
>
> compatible = "fsl,mpc8313-gpio", "fsl,mpc8349-gpio";
>
> > Also I would like to ask if the above device node is written according
> > to bindings ... I think it should be right as I referred
> > 'bootingwithout-of.txt' ... but please correct me if I am worng ? ? ?
> >
>
> See also
> Documentation/powerpc/dts-bindings/fsl/8xxx_gpio.txt.
>
> Also note that current Linux has a driver in
> arch/powerpc/sysdev/mpc8xxx_gpio.c.
>
> -Scott
>

Re: Regarding irq_of_parse_and_map

[Scott Wood]

On Wed, Feb 18, 2009 at 05:31:34PM +0530, Vijay Nikam wrote:
> > Don't specify this explicitly.  Please base new development off of the
> > device tree that is in upstream Linux, not the very old tree in your BSP.
> 
> May I know the reason why I should not specify it explicitly ? ? ?

Because dtc will generate phandles automatically when you reference the
node with the & operator.

> Also what would be the problem if I do in the same way as it is given
> in BSP mpc8313erdb.dts ? ? ?

Do you want your changes to ever make it into the upstream kernel?

> And should I use gpio-controller as a gpio device node ? ? ?

Yes, the node should label itself as a gpio controller.

-Scott

Re: Regarding irq_of_parse_and_map

[Vijay Nikam]

> Because dtc will generate phandles automatically when you reference the
> node with the & operator.

Yes the same statement I found in dts-bindings for gpio txt, sorry I
missed it somehow ...

> Do you want your changes to ever make it into the upstream kernel?

Yes I would like to do that ... but the reason I asked is as it is my
first try so I am thinking that I will edit the same file and do it in
the same way ofcourse I will follow for device node gpio-controller
the new apporach and later if it works then I will create new dts with
upstream Linux base ...

Now I have created the mpc8313erdb.dts with gpio-controller device
node. I would like to ask that now I should compile it with dtc and
generate dtb and I should load this dtb on board/target, Right ? ? ?
please correct me if I am wrong ...

Also is it possible to compile device tree on Linux host and genreate
dtb for powerpc ? ? ? If yes, then how ? ? ? please let me know ...
thanks ...

Before I tried to generate virtual irq using irq_create_mapping and I
got the same number as hw_irq_no i.e. 74 as virtual irq. Also the
entry was made in proc/interrupts and trigger was 8 (Level). But when
I tried to interrupt and the handler was never called ? ? ? Was it
because of gpio device node missing in device tree ? ? ? please let me
know ... thanks ...

Kindly please acknowledge ... thank you ...

Kind Regards,
Vijay Nikam


On 2/18/09, Scott Wood <scottwood@freescale.com> wrote:
> On Wed, Feb 18, 2009 at 05:31:34PM +0530, Vijay Nikam wrote:
> > > Don't specify this explicitly.  Please base new development off of the
> > > device tree that is in upstream Linux, not the very old tree in your BSP.
> >
> > May I know the reason why I should not specify it explicitly ? ? ?
>
> Because dtc will generate phandles automatically when you reference the
> node with the & operator.
>
> > Also what would be the problem if I do in the same way as it is given
> > in BSP mpc8313erdb.dts ? ? ?
>
> Do you want your changes to ever make it into the upstream kernel?
>
> > And should I use gpio-controller as a gpio device node ? ? ?
>
> Yes, the node should label itself as a gpio controller.
>
> -Scott
>

Re: Regarding irq_of_parse_and_map

[Jon Loeliger]

On Thu, 2009-02-19 at 17:21 +0530, Vijay Nikam wrote:

> Also is it possible to compile device tree on Linux host and genreate
> dtb for powerpc ? ? ? If yes, then how ? ? ? please let me know ...
> thanks ...

Uh, get a copy of the DTC using:

    $ git clone git://git.jdl.com/software/dtc.git
    $ cd dtc
    $ make

HTH,
jdl