diff mbox

[RFC,v2:,1/2] dt-bindings: Document the hi3660 reset bindings

Message ID 1479888476-13138-2-git-send-email-zhangfei.gao@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Zhangfei Gao Nov. 23, 2016, 8:07 a.m. UTC
Add DT bindings documentation for hi3660 SoC reset controller.

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
---
 .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt

Comments

Philipp Zabel Nov. 24, 2016, 9:26 a.m. UTC | #1
Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> Add DT bindings documentation for hi3660 SoC reset controller.
> 
> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> ---
>  .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> 
> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> new file mode 100644
> index 0000000..250daf2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> @@ -0,0 +1,51 @@
> +Hisilicon System Reset Controller
> +======================================
> +
> +Please also refer to reset.txt in this directory for common reset
> +controller binding usage.
> +
> +The reset controller registers are part of the system-ctl block on
> +hi3660 SoC.
> +
> +Required properties:
> +- compatible: should be
> +		 "hisilicon,hi3660-reset"
> +- #reset-cells: 1, see below
> +- hisi,rst-syscon: phandle of the reset's syscon.
> +- hisi,reset-bits: Contains the reset control register information
> +		  Should contain 2 cells for each reset exposed to
> +		  consumers, defined as:
> +			Cell #1 : offset from the syscon register base
> +			Cell #2 : bits position of the control register
> +
> +Example:
> +	iomcu: iomcu@ffd7e000 {
> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> +	};
> +
> +	iomcu_rst: iomcu_rst_controller {

This should be
	iomcu_rst: reset-controller {

> +		compatible = "hisilicon,hi3660-reset";
> +		#reset-cells = <1>;
> +		hisi,rst-syscon = <&iomcu>;
> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> +				   0x20 0x10		/* 1: i2c1 */
> +				   0x20 0x20		/* 2: i2c2 */
> +				   0x20 0x8000000>;	/* 3: i2c6 */
> +	};

The reset lines are controlled through iomcu bits, is there a reason not
to put the iomcu_rst node inside the iomcu node? That way the
hisi,rst-syscon property could be removed and the syscon could be
retrieved via the reset-controller parent node.

> +Specifying reset lines connected to IP modules
> +==============================================
> +example:
> +
> +        i2c0: i2c@..... {
> +                ...
> +		resets = <&iomcu_rst 0>;
> +                ...
> +        };
> +
> +	i2c1: i2c@..... {
> +                ...
> +		resets = <&iomcu_rst 1>;
> +                ...
> +        };

regards
Philipp
Zhangfei Gao Nov. 24, 2016, 9:40 a.m. UTC | #2
On 2016年11月24日 17:26, Philipp Zabel wrote:
> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
>> Add DT bindings documentation for hi3660 SoC reset controller.
>>
>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>> ---
>>   .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>>   1 file changed, 51 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>
>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>> new file mode 100644
>> index 0000000..250daf2
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>> @@ -0,0 +1,51 @@
>> +Hisilicon System Reset Controller
>> +======================================
>> +
>> +Please also refer to reset.txt in this directory for common reset
>> +controller binding usage.
>> +
>> +The reset controller registers are part of the system-ctl block on
>> +hi3660 SoC.
>> +
>> +Required properties:
>> +- compatible: should be
>> +		 "hisilicon,hi3660-reset"
>> +- #reset-cells: 1, see below
>> +- hisi,rst-syscon: phandle of the reset's syscon.
>> +- hisi,reset-bits: Contains the reset control register information
>> +		  Should contain 2 cells for each reset exposed to
>> +		  consumers, defined as:
>> +			Cell #1 : offset from the syscon register base
>> +			Cell #2 : bits position of the control register
>> +
>> +Example:
>> +	iomcu: iomcu@ffd7e000 {
>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
>> +	};
>> +
>> +	iomcu_rst: iomcu_rst_controller {
> This should be
> 	iomcu_rst: reset-controller {
>
>> +		compatible = "hisilicon,hi3660-reset";
>> +		#reset-cells = <1>;
>> +		hisi,rst-syscon = <&iomcu>;
>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
>> +				   0x20 0x10		/* 1: i2c1 */
>> +				   0x20 0x20		/* 2: i2c2 */
>> +				   0x20 0x8000000>;	/* 3: i2c6 */
>> +	};
> The reset lines are controlled through iomcu bits, is there a reason not
> to put the iomcu_rst node inside the iomcu node? That way the
> hisi,rst-syscon property could be removed and the syscon could be
> retrieved via the reset-controller parent node.
iomcu is common registers, controls clock and reset, etc.
So we use syscon, without mapping the registers everywhere.
It is common case in hisilicon, same in hi6220.

Also the #clock-cells and #reset-cells can not be put in the same node,
if they are both using probe, since reset_probe will not be called.

So we use hisi,rst-syscon as a general solution.

Thanks
Philipp Zabel Nov. 24, 2016, 9:50 a.m. UTC | #3
Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
> 
> On 2016年11月24日 17:26, Philipp Zabel wrote:
> > Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> >> Add DT bindings documentation for hi3660 SoC reset controller.
> >>
> >> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >> ---
> >>   .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
> >>   1 file changed, 51 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >> new file mode 100644
> >> index 0000000..250daf2
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >> @@ -0,0 +1,51 @@
> >> +Hisilicon System Reset Controller
> >> +======================================
> >> +
> >> +Please also refer to reset.txt in this directory for common reset
> >> +controller binding usage.
> >> +
> >> +The reset controller registers are part of the system-ctl block on
> >> +hi3660 SoC.
> >> +
> >> +Required properties:
> >> +- compatible: should be
> >> +		 "hisilicon,hi3660-reset"
> >> +- #reset-cells: 1, see below
> >> +- hisi,rst-syscon: phandle of the reset's syscon.
> >> +- hisi,reset-bits: Contains the reset control register information
> >> +		  Should contain 2 cells for each reset exposed to
> >> +		  consumers, defined as:
> >> +			Cell #1 : offset from the syscon register base
> >> +			Cell #2 : bits position of the control register
> >> +
> >> +Example:
> >> +	iomcu: iomcu@ffd7e000 {
> >> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> >> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >> +	};
> >> +
> >> +	iomcu_rst: iomcu_rst_controller {
> > This should be
> > 	iomcu_rst: reset-controller {
> >
> >> +		compatible = "hisilicon,hi3660-reset";
> >> +		#reset-cells = <1>;
> >> +		hisi,rst-syscon = <&iomcu>;
> >> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> >> +				   0x20 0x10		/* 1: i2c1 */
> >> +				   0x20 0x20		/* 2: i2c2 */
> >> +				   0x20 0x8000000>;	/* 3: i2c6 */
> >> +	};
> > The reset lines are controlled through iomcu bits, is there a reason not
> > to put the iomcu_rst node inside the iomcu node? That way the
> > hisi,rst-syscon property could be removed and the syscon could be
> > retrieved via the reset-controller parent node.
> iomcu is common registers, controls clock and reset, etc.
> So we use syscon, without mapping the registers everywhere.
> It is common case in hisilicon, same in hi6220.
>
> Also the #clock-cells and #reset-cells can not be put in the same node,
> if they are both using probe, since reset_probe will not be called.
> 
> So we use hisi,rst-syscon as a general solution.

What I meant is this:

	iomcu: iomcu@ffd7e000 {
		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
		reg = <0x0 0xffd7e000 0x0 0x1000>;

		iomcu_rst: reset-controller {
			compatible = "hisilicon,hi3660-reset";
			#reset-cells = <1>;
			hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
					   0x20 0x10		/* 1: i2c1 */
					   0x20 0x20		/* 2: i2c2 */
					   0x20 0x8000000>;	/* 3: i2c6 */
		};
	};

regards
Philipp
Zhangfei Gao Nov. 24, 2016, 10:20 a.m. UTC | #4
On 2016年11月24日 17:50, Philipp Zabel wrote:
> Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
>> On 2016年11月24日 17:26, Philipp Zabel wrote:
>>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
>>>> Add DT bindings documentation for hi3660 SoC reset controller.
>>>>
>>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>>>> ---
>>>>    .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>>>>    1 file changed, 51 insertions(+)
>>>>    create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>> new file mode 100644
>>>> index 0000000..250daf2
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>> @@ -0,0 +1,51 @@
>>>> +Hisilicon System Reset Controller
>>>> +======================================
>>>> +
>>>> +Please also refer to reset.txt in this directory for common reset
>>>> +controller binding usage.
>>>> +
>>>> +The reset controller registers are part of the system-ctl block on
>>>> +hi3660 SoC.
>>>> +
>>>> +Required properties:
>>>> +- compatible: should be
>>>> +		 "hisilicon,hi3660-reset"
>>>> +- #reset-cells: 1, see below
>>>> +- hisi,rst-syscon: phandle of the reset's syscon.
>>>> +- hisi,reset-bits: Contains the reset control register information
>>>> +		  Should contain 2 cells for each reset exposed to
>>>> +		  consumers, defined as:
>>>> +			Cell #1 : offset from the syscon register base
>>>> +			Cell #2 : bits position of the control register
>>>> +
>>>> +Example:
>>>> +	iomcu: iomcu@ffd7e000 {
>>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
>>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
>>>> +	};
>>>> +
>>>> +	iomcu_rst: iomcu_rst_controller {
>>> This should be
>>> 	iomcu_rst: reset-controller {
>>>
>>>> +		compatible = "hisilicon,hi3660-reset";
>>>> +		#reset-cells = <1>;
>>>> +		hisi,rst-syscon = <&iomcu>;
>>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
>>>> +				   0x20 0x10		/* 1: i2c1 */
>>>> +				   0x20 0x20		/* 2: i2c2 */
>>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
>>>> +	};
>>> The reset lines are controlled through iomcu bits, is there a reason not
>>> to put the iomcu_rst node inside the iomcu node? That way the
>>> hisi,rst-syscon property could be removed and the syscon could be
>>> retrieved via the reset-controller parent node.
>> iomcu is common registers, controls clock and reset, etc.
>> So we use syscon, without mapping the registers everywhere.
>> It is common case in hisilicon, same in hi6220.
>>
>> Also the #clock-cells and #reset-cells can not be put in the same node,
>> if they are both using probe, since reset_probe will not be called.
>>
>> So we use hisi,rst-syscon as a general solution.
> What I meant is this:
>
> 	iomcu: iomcu@ffd7e000 {
> 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
> 		reg = <0x0 0xffd7e000 0x0 0x1000>;
#clock-cells = <1>;
In my test, if there add #clock-cells = <1>, reset_probe will not be 
called any more.
Since clk_probe is called first.
No matter iomcu_rst is child node or not.

Thanks
>
> 		iomcu_rst: reset-controller {
> 			compatible = "hisilicon,hi3660-reset";
> 			#reset-cells = <1>;
> 			hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> 					   0x20 0x10		/* 1: i2c1 */
> 					   0x20 0x20		/* 2: i2c2 */
> 					   0x20 0x8000000>;	/* 3: i2c6 */
> 		};
> 	};
>
> regards
> Philipp
>
Zhangfei Gao Nov. 25, 2016, 2:38 a.m. UTC | #5
On Wed, Nov 23, 2016 at 4:07 PM, Zhangfei Gao <zhangfei.gao@linaro.org> wrote:
> Add DT bindings documentation for hi3660 SoC reset controller.
>
> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> ---
>  .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>
> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> new file mode 100644
> index 0000000..250daf2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> @@ -0,0 +1,51 @@
> +Hisilicon System Reset Controller
> +======================================
> +
> +Please also refer to reset.txt in this directory for common reset
> +controller binding usage.
> +
> +The reset controller registers are part of the system-ctl block on
> +hi3660 SoC.
> +
> +Required properties:
> +- compatible: should be
> +                "hisilicon,hi3660-reset"
> +- #reset-cells: 1, see below
> +- hisi,rst-syscon: phandle of the reset's syscon.
> +- hisi,reset-bits: Contains the reset control register information
> +                 Should contain 2 cells for each reset exposed to
> +                 consumers, defined as:
> +                       Cell #1 : offset from the syscon register base
> +                       Cell #2 : bits position of the control register
> +
> +Example:
> +       iomcu: iomcu@ffd7e000 {
> +               compatible = "hisilicon,hi3660-iomcu", "syscon";
> +               reg = <0x0 0xffd7e000 0x0 0x1000>;
> +       };
> +
> +       iomcu_rst: iomcu_rst_controller {
> +               compatible = "hisilicon,hi3660-reset";
> +               #reset-cells = <1>;
> +               hisi,rst-syscon = <&iomcu>;
> +               hisi,reset-bits = <0x20 0x8             /* 0: i2c0 */
> +                                  0x20 0x10            /* 1: i2c1 */
> +                                  0x20 0x20            /* 2: i2c2 */
> +                                  0x20 0x8000000>;     /* 3: i2c6 */
> +       };
> +
> +Specifying reset lines connected to IP modules
> +==============================================
> +example:
> +
> +        i2c0: i2c@..... {
> +                ...
> +               resets = <&iomcu_rst 0>;
> +                ...
> +        };
> +
> +       i2c1: i2c@..... {
> +                ...
> +               resets = <&iomcu_rst 1>;
> +                ...
> +        };
> --
> 2.7.4


Sorry, missing cc when send-email.
Help take a look.

Thanks
Zhangfei Gao Nov. 25, 2016, 3:04 a.m. UTC | #6
On 2016年11月24日 17:26, Philipp Zabel wrote:
> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
>> Add DT bindings documentation for hi3660 SoC reset controller.
>>
>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>> ---
>>   .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>>   1 file changed, 51 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>
>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>> new file mode 100644
>> index 0000000..250daf2
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>> @@ -0,0 +1,51 @@
>> +Hisilicon System Reset Controller
>> +======================================
>> +
>> +Please also refer to reset.txt in this directory for common reset
>> +controller binding usage.
>> +
>> +The reset controller registers are part of the system-ctl block on
>> +hi3660 SoC.
>> +
>> +Required properties:
>> +- compatible: should be
>> +		 "hisilicon,hi3660-reset"
>> +- #reset-cells: 1, see below
>> +- hisi,rst-syscon: phandle of the reset's syscon.
>> +- hisi,reset-bits: Contains the reset control register information
>> +		  Should contain 2 cells for each reset exposed to
>> +		  consumers, defined as:
>> +			Cell #1 : offset from the syscon register base
>> +			Cell #2 : bits position of the control register
>> +
>> +Example:
>> +	iomcu: iomcu@ffd7e000 {
>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
>> +	};
>> +
>> +	iomcu_rst: iomcu_rst_controller {
> This should be
> 	iomcu_rst: reset-controller {
By the way, could I keep the original name?
Since there will be build error if several nodes use the same name.
like:
-               iomcu_rst: iomcu_rst_controller {
+               iomcu_rst: reset-controller {

-               crg_rst: crg_rst_controller {
+               crg_rst: reset-controller {

Thanks
Philipp Zabel Nov. 25, 2016, 10:25 a.m. UTC | #7
Am Donnerstag, den 24.11.2016, 18:20 +0800 schrieb zhangfei:
> 
> On 2016年11月24日 17:50, Philipp Zabel wrote:
> > Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
> >> On 2016年11月24日 17:26, Philipp Zabel wrote:
> >>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> >>>> Add DT bindings documentation for hi3660 SoC reset controller.
> >>>>
> >>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >>>> ---
> >>>>    .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
> >>>>    1 file changed, 51 insertions(+)
> >>>>    create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>> new file mode 100644
> >>>> index 0000000..250daf2
> >>>> --- /dev/null
> >>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>> @@ -0,0 +1,51 @@
> >>>> +Hisilicon System Reset Controller
> >>>> +======================================
> >>>> +
> >>>> +Please also refer to reset.txt in this directory for common reset
> >>>> +controller binding usage.
> >>>> +
> >>>> +The reset controller registers are part of the system-ctl block on
> >>>> +hi3660 SoC.
> >>>> +
> >>>> +Required properties:
> >>>> +- compatible: should be
> >>>> +		 "hisilicon,hi3660-reset"
> >>>> +- #reset-cells: 1, see below
> >>>> +- hisi,rst-syscon: phandle of the reset's syscon.
> >>>> +- hisi,reset-bits: Contains the reset control register information
> >>>> +		  Should contain 2 cells for each reset exposed to
> >>>> +		  consumers, defined as:
> >>>> +			Cell #1 : offset from the syscon register base
> >>>> +			Cell #2 : bits position of the control register
> >>>> +
> >>>> +Example:
> >>>> +	iomcu: iomcu@ffd7e000 {
> >>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> >>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >>>> +	};
> >>>> +
> >>>> +	iomcu_rst: iomcu_rst_controller {
> >>> This should be
> >>> 	iomcu_rst: reset-controller {
> >>>
> >>>> +		compatible = "hisilicon,hi3660-reset";
> >>>> +		#reset-cells = <1>;
> >>>> +		hisi,rst-syscon = <&iomcu>;
> >>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> >>>> +				   0x20 0x10		/* 1: i2c1 */
> >>>> +				   0x20 0x20		/* 2: i2c2 */
> >>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
> >>>> +	};
> >>> The reset lines are controlled through iomcu bits, is there a reason not
> >>> to put the iomcu_rst node inside the iomcu node? That way the
> >>> hisi,rst-syscon property could be removed and the syscon could be
> >>> retrieved via the reset-controller parent node.
> >> iomcu is common registers, controls clock and reset, etc.
> >> So we use syscon, without mapping the registers everywhere.
> >> It is common case in hisilicon, same in hi6220.
> >>
> >> Also the #clock-cells and #reset-cells can not be put in the same node,
> >> if they are both using probe, since reset_probe will not be called.
> >>
> >> So we use hisi,rst-syscon as a general solution.
> > What I meant is this:
> >
> > 	iomcu: iomcu@ffd7e000 {
> > 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
> > 		reg = <0x0 0xffd7e000 0x0 0x1000>;
> #clock-cells = <1>;
>
> In my test, if there add #clock-cells = <1>, reset_probe will not be 
> called any more.
> Since clk_probe is called first.
> No matter iomcu_rst is child node or not.

I don't understand this, does the clock driver bind to the iomcu node
using CLK_OF_DECLARE_DRIVER(..., "hisilicon,hi3660-iomcu", ...)?

My comment was based only on this reset binding documentation and the
example DT snippet. Could you point me to the clock driver probe code
and show me a more complete part of the hi3660 device tree?

regards
Philipp
Philipp Zabel Nov. 25, 2016, 10:27 a.m. UTC | #8
Am Freitag, den 25.11.2016, 11:04 +0800 schrieb zhangfei:
> 
> On 2016年11月24日 17:26, Philipp Zabel wrote:
> > Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> >> Add DT bindings documentation for hi3660 SoC reset controller.
> >>
> >> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >> ---
> >>   .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
> >>   1 file changed, 51 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >> new file mode 100644
> >> index 0000000..250daf2
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >> @@ -0,0 +1,51 @@
> >> +Hisilicon System Reset Controller
> >> +======================================
> >> +
> >> +Please also refer to reset.txt in this directory for common reset
> >> +controller binding usage.
> >> +
> >> +The reset controller registers are part of the system-ctl block on
> >> +hi3660 SoC.
> >> +
> >> +Required properties:
> >> +- compatible: should be
> >> +		 "hisilicon,hi3660-reset"
> >> +- #reset-cells: 1, see below
> >> +- hisi,rst-syscon: phandle of the reset's syscon.
> >> +- hisi,reset-bits: Contains the reset control register information
> >> +		  Should contain 2 cells for each reset exposed to
> >> +		  consumers, defined as:
> >> +			Cell #1 : offset from the syscon register base
> >> +			Cell #2 : bits position of the control register
> >> +
> >> +Example:
> >> +	iomcu: iomcu@ffd7e000 {
> >> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> >> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >> +	};
> >> +
> >> +	iomcu_rst: iomcu_rst_controller {
> > This should be
> > 	iomcu_rst: reset-controller {
> By the way, could I keep the original name?
> Since there will be build error if several nodes use the same name.
> like:
> -               iomcu_rst: iomcu_rst_controller {
> +               iomcu_rst: reset-controller {
> 
> -               crg_rst: crg_rst_controller {
> +               crg_rst: reset-controller {

That should not be a problem if they are moved inside the controlling
node:

	iomcu {
		iomcu_rst: reset-controller {
		};
	};

	crg {
		crg_rst: reset-controller {
		};
	};

regards
Philipp
Zhangfei Gao Nov. 25, 2016, 10:42 a.m. UTC | #9
On 2016年11月25日 18:25, Philipp Zabel wrote:
> Am Donnerstag, den 24.11.2016, 18:20 +0800 schrieb zhangfei:
>> On 2016年11月24日 17:50, Philipp Zabel wrote:
>>> Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
>>>> On 2016年11月24日 17:26, Philipp Zabel wrote:
>>>>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
>>>>>> Add DT bindings documentation for hi3660 SoC reset controller.
>>>>>>
>>>>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>>>>>> ---
>>>>>>     .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>>>>>>     1 file changed, 51 insertions(+)
>>>>>>     create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>> new file mode 100644
>>>>>> index 0000000..250daf2
>>>>>> --- /dev/null
>>>>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>> @@ -0,0 +1,51 @@
>>>>>> +Hisilicon System Reset Controller
>>>>>> +======================================
>>>>>> +
>>>>>> +Please also refer to reset.txt in this directory for common reset
>>>>>> +controller binding usage.
>>>>>> +
>>>>>> +The reset controller registers are part of the system-ctl block on
>>>>>> +hi3660 SoC.
>>>>>> +
>>>>>> +Required properties:
>>>>>> +- compatible: should be
>>>>>> +		 "hisilicon,hi3660-reset"
>>>>>> +- #reset-cells: 1, see below
>>>>>> +- hisi,rst-syscon: phandle of the reset's syscon.
>>>>>> +- hisi,reset-bits: Contains the reset control register information
>>>>>> +		  Should contain 2 cells for each reset exposed to
>>>>>> +		  consumers, defined as:
>>>>>> +			Cell #1 : offset from the syscon register base
>>>>>> +			Cell #2 : bits position of the control register
>>>>>> +
>>>>>> +Example:
>>>>>> +	iomcu: iomcu@ffd7e000 {
>>>>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
>>>>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
>>>>>> +	};
>>>>>> +
>>>>>> +	iomcu_rst: iomcu_rst_controller {
>>>>> This should be
>>>>> 	iomcu_rst: reset-controller {
>>>>>
>>>>>> +		compatible = "hisilicon,hi3660-reset";
>>>>>> +		#reset-cells = <1>;
>>>>>> +		hisi,rst-syscon = <&iomcu>;
>>>>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
>>>>>> +				   0x20 0x10		/* 1: i2c1 */
>>>>>> +				   0x20 0x20		/* 2: i2c2 */
>>>>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
>>>>>> +	};
>>>>> The reset lines are controlled through iomcu bits, is there a reason not
>>>>> to put the iomcu_rst node inside the iomcu node? That way the
>>>>> hisi,rst-syscon property could be removed and the syscon could be
>>>>> retrieved via the reset-controller parent node.
>>>> iomcu is common registers, controls clock and reset, etc.
>>>> So we use syscon, without mapping the registers everywhere.
>>>> It is common case in hisilicon, same in hi6220.
>>>>
>>>> Also the #clock-cells and #reset-cells can not be put in the same node,
>>>> if they are both using probe, since reset_probe will not be called.
>>>>
>>>> So we use hisi,rst-syscon as a general solution.
>>> What I meant is this:
>>>
>>> 	iomcu: iomcu@ffd7e000 {
>>> 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
>>> 		reg = <0x0 0xffd7e000 0x0 0x1000>;
>> #clock-cells = <1>;
>>
>> In my test, if there add #clock-cells = <1>, reset_probe will not be
>> called any more.
>> Since clk_probe is called first.
>> No matter iomcu_rst is child node or not.
> I don't understand this, does the clock driver bind to the iomcu node
> using CLK_OF_DECLARE_DRIVER(..., "hisilicon,hi3660-iomcu", ...)?

This method:CLK_OF_DECLARE_DRIVER is not prefered in clock,
and we have to use probe instead, to make all driver build as modules as 
possible.

For example hi3660.
static struct platform_driver hi3660_clk_driver = {
         .probe          = hi3660_clk_probe,
         .driver         = {
                 .name   = "hi3660-clk",
                 .of_match_table = hi3660_clk_match_table,
         },
};

static int __init hi3660_clk_init(void)
{
         return platform_driver_register(&hi3660_clk_driver);
}
core_initcall(hi3660_clk_init);

And many examples in drivers/clock, just
#grep -rn probe drivers/clk/
drivers/clk/clk-axm5516.c:587:    .probe        = axmclk_probe,

If the parent node happen to be clock, and set

#clock-cells = <1>;
Then clock_probe/hi3660_clk_probe will be called first.
But reset_probe will not be called any more.

Thanks

>
> My comment was based only on this reset binding documentation and the
> example DT snippet. Could you point me to the clock driver probe code
> and show me a more complete part of the hi3660 device tree?
>
> regards
> Philipp
>
Philipp Zabel Nov. 25, 2016, 10:54 a.m. UTC | #10
Am Freitag, den 25.11.2016, 18:42 +0800 schrieb zhangfei:
> 
> On 2016年11月25日 18:25, Philipp Zabel wrote:
> > Am Donnerstag, den 24.11.2016, 18:20 +0800 schrieb zhangfei:
> >> On 2016年11月24日 17:50, Philipp Zabel wrote:
> >>> Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
> >>>> On 2016年11月24日 17:26, Philipp Zabel wrote:
> >>>>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> >>>>>> Add DT bindings documentation for hi3660 SoC reset controller.
> >>>>>>
> >>>>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >>>>>> ---
> >>>>>>     .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
> >>>>>>     1 file changed, 51 insertions(+)
> >>>>>>     create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>>
> >>>>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>> new file mode 100644
> >>>>>> index 0000000..250daf2
> >>>>>> --- /dev/null
> >>>>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>> @@ -0,0 +1,51 @@
> >>>>>> +Hisilicon System Reset Controller
> >>>>>> +======================================
> >>>>>> +
> >>>>>> +Please also refer to reset.txt in this directory for common reset
> >>>>>> +controller binding usage.
> >>>>>> +
> >>>>>> +The reset controller registers are part of the system-ctl block on
> >>>>>> +hi3660 SoC.
> >>>>>> +
> >>>>>> +Required properties:
> >>>>>> +- compatible: should be
> >>>>>> +		 "hisilicon,hi3660-reset"
> >>>>>> +- #reset-cells: 1, see below
> >>>>>> +- hisi,rst-syscon: phandle of the reset's syscon.
> >>>>>> +- hisi,reset-bits: Contains the reset control register information
> >>>>>> +		  Should contain 2 cells for each reset exposed to
> >>>>>> +		  consumers, defined as:
> >>>>>> +			Cell #1 : offset from the syscon register base
> >>>>>> +			Cell #2 : bits position of the control register
> >>>>>> +
> >>>>>> +Example:
> >>>>>> +	iomcu: iomcu@ffd7e000 {
> >>>>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> >>>>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >>>>>> +	};
> >>>>>> +
> >>>>>> +	iomcu_rst: iomcu_rst_controller {
> >>>>> This should be
> >>>>> 	iomcu_rst: reset-controller {
> >>>>>
> >>>>>> +		compatible = "hisilicon,hi3660-reset";
> >>>>>> +		#reset-cells = <1>;
> >>>>>> +		hisi,rst-syscon = <&iomcu>;
> >>>>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> >>>>>> +				   0x20 0x10		/* 1: i2c1 */
> >>>>>> +				   0x20 0x20		/* 2: i2c2 */
> >>>>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
> >>>>>> +	};
> >>>>> The reset lines are controlled through iomcu bits, is there a reason not
> >>>>> to put the iomcu_rst node inside the iomcu node? That way the
> >>>>> hisi,rst-syscon property could be removed and the syscon could be
> >>>>> retrieved via the reset-controller parent node.
> >>>> iomcu is common registers, controls clock and reset, etc.
> >>>> So we use syscon, without mapping the registers everywhere.
> >>>> It is common case in hisilicon, same in hi6220.
> >>>>
> >>>> Also the #clock-cells and #reset-cells can not be put in the same node,
> >>>> if they are both using probe, since reset_probe will not be called.
> >>>>
> >>>> So we use hisi,rst-syscon as a general solution.
> >>> What I meant is this:
> >>>
> >>> 	iomcu: iomcu@ffd7e000 {
> >>> 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
> >>> 		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >> #clock-cells = <1>;
> >>
> >> In my test, if there add #clock-cells = <1>, reset_probe will not be
> >> called any more.
> >> Since clk_probe is called first.
> >> No matter iomcu_rst is child node or not.
> > I don't understand this, does the clock driver bind to the iomcu node
> > using CLK_OF_DECLARE_DRIVER(..., "hisilicon,hi3660-iomcu", ...)?
> 
> This method:CLK_OF_DECLARE_DRIVER is not prefered in clock,
> and we have to use probe instead, to make all driver build as modules as 
> possible.
> 
> For example hi3660.
> static struct platform_driver hi3660_clk_driver = {
>          .probe          = hi3660_clk_probe,
>          .driver         = {
>                  .name   = "hi3660-clk",
>                  .of_match_table = hi3660_clk_match_table,
>          },
> };

hi3660_clk_match_table contains the "hisilicon,hi3660-iomcu" compatible?
If so, you could call
	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
from hi3660_clk_probe instead of using "simple-mfd" to probe the iomcu
node's children.

regards
Philipp
Zhangfei Gao Nov. 25, 2016, 12:08 p.m. UTC | #11
On 2016年11月25日 18:54, Philipp Zabel wrote:
> Am Freitag, den 25.11.2016, 18:42 +0800 schrieb zhangfei:
>> On 2016年11月25日 18:25, Philipp Zabel wrote:
>>> Am Donnerstag, den 24.11.2016, 18:20 +0800 schrieb zhangfei:
>>>> On 2016年11月24日 17:50, Philipp Zabel wrote:
>>>>> Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
>>>>>> On 2016年11月24日 17:26, Philipp Zabel wrote:
>>>>>>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
>>>>>>>> Add DT bindings documentation for hi3660 SoC reset controller.
>>>>>>>>
>>>>>>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>>>>>>>> ---
>>>>>>>>      .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
>>>>>>>>      1 file changed, 51 insertions(+)
>>>>>>>>      create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>>>>
>>>>>>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>>>> new file mode 100644
>>>>>>>> index 0000000..250daf2
>>>>>>>> --- /dev/null
>>>>>>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
>>>>>>>> @@ -0,0 +1,51 @@
>>>>>>>> +Hisilicon System Reset Controller
>>>>>>>> +======================================
>>>>>>>> +
>>>>>>>> +Please also refer to reset.txt in this directory for common reset
>>>>>>>> +controller binding usage.
>>>>>>>> +
>>>>>>>> +The reset controller registers are part of the system-ctl block on
>>>>>>>> +hi3660 SoC.
>>>>>>>> +
>>>>>>>> +Required properties:
>>>>>>>> +- compatible: should be
>>>>>>>> +		 "hisilicon,hi3660-reset"
>>>>>>>> +- #reset-cells: 1, see below
>>>>>>>> +- hisi,rst-syscon: phandle of the reset's syscon.
>>>>>>>> +- hisi,reset-bits: Contains the reset control register information
>>>>>>>> +		  Should contain 2 cells for each reset exposed to
>>>>>>>> +		  consumers, defined as:
>>>>>>>> +			Cell #1 : offset from the syscon register base
>>>>>>>> +			Cell #2 : bits position of the control register
>>>>>>>> +
>>>>>>>> +Example:
>>>>>>>> +	iomcu: iomcu@ffd7e000 {
>>>>>>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
>>>>>>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
>>>>>>>> +	};
>>>>>>>> +
>>>>>>>> +	iomcu_rst: iomcu_rst_controller {
>>>>>>> This should be
>>>>>>> 	iomcu_rst: reset-controller {
>>>>>>>
>>>>>>>> +		compatible = "hisilicon,hi3660-reset";
>>>>>>>> +		#reset-cells = <1>;
>>>>>>>> +		hisi,rst-syscon = <&iomcu>;
>>>>>>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
>>>>>>>> +				   0x20 0x10		/* 1: i2c1 */
>>>>>>>> +				   0x20 0x20		/* 2: i2c2 */
>>>>>>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
>>>>>>>> +	};
>>>>>>> The reset lines are controlled through iomcu bits, is there a reason not
>>>>>>> to put the iomcu_rst node inside the iomcu node? That way the
>>>>>>> hisi,rst-syscon property could be removed and the syscon could be
>>>>>>> retrieved via the reset-controller parent node.
>>>>>> iomcu is common registers, controls clock and reset, etc.
>>>>>> So we use syscon, without mapping the registers everywhere.
>>>>>> It is common case in hisilicon, same in hi6220.
>>>>>>
>>>>>> Also the #clock-cells and #reset-cells can not be put in the same node,
>>>>>> if they are both using probe, since reset_probe will not be called.
>>>>>>
>>>>>> So we use hisi,rst-syscon as a general solution.
>>>>> What I meant is this:
>>>>>
>>>>> 	iomcu: iomcu@ffd7e000 {
>>>>> 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
>>>>> 		reg = <0x0 0xffd7e000 0x0 0x1000>;
>>>> #clock-cells = <1>;
>>>>
>>>> In my test, if there add #clock-cells = <1>, reset_probe will not be
>>>> called any more.
>>>> Since clk_probe is called first.
>>>> No matter iomcu_rst is child node or not.
>>> I don't understand this, does the clock driver bind to the iomcu node
>>> using CLK_OF_DECLARE_DRIVER(..., "hisilicon,hi3660-iomcu", ...)?
>> This method:CLK_OF_DECLARE_DRIVER is not prefered in clock,
>> and we have to use probe instead, to make all driver build as modules as
>> possible.
>>
>> For example hi3660.
>> static struct platform_driver hi3660_clk_driver = {
>>           .probe          = hi3660_clk_probe,
>>           .driver         = {
>>                   .name   = "hi3660-clk",
>>                   .of_match_table = hi3660_clk_match_table,
>>           },
>> };
> hi3660_clk_match_table contains the "hisilicon,hi3660-iomcu" compatible?
> If so, you could call
> 	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
> from hi3660_clk_probe instead of using "simple-mfd" to probe the iomcu
> node's children.

Not using simple-mfd:

Like
static const struct of_device_id hi3660_clk_match_table[] = {
         { .compatible = "hisilicon,hi3660-iomcu", },
         { }
};
MODULE_DEVICE_TABLE(of, hi3660_clk_match_table);

static int hi3660_clk_probe(struct platform_device *pdev)
{
         struct device *dev = &pdev->dev;
         struct device_node *np = pdev->dev.of_node;
         const struct of_device_id *of_id;
         enum hi3660_clk_type type;

         of_id = of_match_device(hi3660_clk_match_table, dev);
         if (!of_id)
                 return -EINVAL;
~
}

If put iomcu_rst as child node, and set #clock-cells = <1> to iomcu,
then hi3660_clk_probe is called, hi3660_reset_probe will not be called.
So using "hisi,rst-syscon" as pointer does not have the issue.

Thanks
Philipp Zabel Nov. 30, 2016, 10:03 a.m. UTC | #12
Am Freitag, den 25.11.2016, 20:08 +0800 schrieb zhangfei:
> 
> On 2016年11月25日 18:54, Philipp Zabel wrote:
> > Am Freitag, den 25.11.2016, 18:42 +0800 schrieb zhangfei:
> >> On 2016年11月25日 18:25, Philipp Zabel wrote:
> >>> Am Donnerstag, den 24.11.2016, 18:20 +0800 schrieb zhangfei:
> >>>> On 2016年11月24日 17:50, Philipp Zabel wrote:
> >>>>> Am Donnerstag, den 24.11.2016, 17:40 +0800 schrieb zhangfei:
> >>>>>> On 2016年11月24日 17:26, Philipp Zabel wrote:
> >>>>>>> Am Mittwoch, den 23.11.2016, 16:07 +0800 schrieb Zhangfei Gao:
> >>>>>>>> Add DT bindings documentation for hi3660 SoC reset controller.
> >>>>>>>>
> >>>>>>>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >>>>>>>> ---
> >>>>>>>>      .../bindings/reset/hisilicon,hi3660-reset.txt      | 51 ++++++++++++++++++++++
> >>>>>>>>      1 file changed, 51 insertions(+)
> >>>>>>>>      create mode 100644 Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>>>>
> >>>>>>>> diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>>>> new file mode 100644
> >>>>>>>> index 0000000..250daf2
> >>>>>>>> --- /dev/null
> >>>>>>>> +++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
> >>>>>>>> @@ -0,0 +1,51 @@
> >>>>>>>> +Hisilicon System Reset Controller
> >>>>>>>> +======================================
> >>>>>>>> +
> >>>>>>>> +Please also refer to reset.txt in this directory for common reset
> >>>>>>>> +controller binding usage.
> >>>>>>>> +
> >>>>>>>> +The reset controller registers are part of the system-ctl block on
> >>>>>>>> +hi3660 SoC.
> >>>>>>>> +
> >>>>>>>> +Required properties:
> >>>>>>>> +- compatible: should be
> >>>>>>>> +		 "hisilicon,hi3660-reset"
> >>>>>>>> +- #reset-cells: 1, see below
> >>>>>>>> +- hisi,rst-syscon: phandle of the reset's syscon.
> >>>>>>>> +- hisi,reset-bits: Contains the reset control register information
> >>>>>>>> +		  Should contain 2 cells for each reset exposed to
> >>>>>>>> +		  consumers, defined as:
> >>>>>>>> +			Cell #1 : offset from the syscon register base
> >>>>>>>> +			Cell #2 : bits position of the control register
> >>>>>>>> +
> >>>>>>>> +Example:
> >>>>>>>> +	iomcu: iomcu@ffd7e000 {
> >>>>>>>> +		compatible = "hisilicon,hi3660-iomcu", "syscon";
> >>>>>>>> +		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >>>>>>>> +	};
> >>>>>>>> +
> >>>>>>>> +	iomcu_rst: iomcu_rst_controller {
> >>>>>>> This should be
> >>>>>>> 	iomcu_rst: reset-controller {
> >>>>>>>
> >>>>>>>> +		compatible = "hisilicon,hi3660-reset";
> >>>>>>>> +		#reset-cells = <1>;
> >>>>>>>> +		hisi,rst-syscon = <&iomcu>;
> >>>>>>>> +		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
> >>>>>>>> +				   0x20 0x10		/* 1: i2c1 */
> >>>>>>>> +				   0x20 0x20		/* 2: i2c2 */
> >>>>>>>> +				   0x20 0x8000000>;	/* 3: i2c6 */
> >>>>>>>> +	};
> >>>>>>> The reset lines are controlled through iomcu bits, is there a reason not
> >>>>>>> to put the iomcu_rst node inside the iomcu node? That way the
> >>>>>>> hisi,rst-syscon property could be removed and the syscon could be
> >>>>>>> retrieved via the reset-controller parent node.
> >>>>>> iomcu is common registers, controls clock and reset, etc.
> >>>>>> So we use syscon, without mapping the registers everywhere.
> >>>>>> It is common case in hisilicon, same in hi6220.
> >>>>>>
> >>>>>> Also the #clock-cells and #reset-cells can not be put in the same node,
> >>>>>> if they are both using probe, since reset_probe will not be called.
> >>>>>>
> >>>>>> So we use hisi,rst-syscon as a general solution.
> >>>>> What I meant is this:
> >>>>>
> >>>>> 	iomcu: iomcu@ffd7e000 {
> >>>>> 		compatible = "hisilicon,hi3660-iomcu", "syscon", "simple-mfd";
> >>>>> 		reg = <0x0 0xffd7e000 0x0 0x1000>;
> >>>> #clock-cells = <1>;
> >>>>
> >>>> In my test, if there add #clock-cells = <1>, reset_probe will not be
> >>>> called any more.
> >>>> Since clk_probe is called first.
> >>>> No matter iomcu_rst is child node or not.
> >>> I don't understand this, does the clock driver bind to the iomcu node
> >>> using CLK_OF_DECLARE_DRIVER(..., "hisilicon,hi3660-iomcu", ...)?
> >> This method:CLK_OF_DECLARE_DRIVER is not prefered in clock,
> >> and we have to use probe instead, to make all driver build as modules as
> >> possible.
> >>
> >> For example hi3660.
> >> static struct platform_driver hi3660_clk_driver = {
> >>           .probe          = hi3660_clk_probe,
> >>           .driver         = {
> >>                   .name   = "hi3660-clk",
> >>                   .of_match_table = hi3660_clk_match_table,
> >>           },
> >> };
> > hi3660_clk_match_table contains the "hisilicon,hi3660-iomcu" compatible?
> > If so, you could call
> > 	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
> > from hi3660_clk_probe instead of using "simple-mfd" to probe the iomcu
> > node's children.
> 
> Not using simple-mfd:
> 
> Like
> static const struct of_device_id hi3660_clk_match_table[] = {
>          { .compatible = "hisilicon,hi3660-iomcu", },
>          { }
> };
> MODULE_DEVICE_TABLE(of, hi3660_clk_match_table);
> 
> static int hi3660_clk_probe(struct platform_device *pdev)
> {
>          struct device *dev = &pdev->dev;
>          struct device_node *np = pdev->dev.of_node;
>          const struct of_device_id *of_id;
>          enum hi3660_clk_type type;
> 
>          of_id = of_match_device(hi3660_clk_match_table, dev);
>          if (!of_id)
>                  return -EINVAL;
> ~
> }
> 
> If put iomcu_rst as child node, and set #clock-cells = <1> to iomcu,
> then hi3660_clk_probe is called, hi3660_reset_probe will not be called.

For hi3660_reset_probe to be called, you'll have to call
of_platform_populate to probe the hi3660-iomcu children in this case.

> So using "hisi,rst-syscon" as pointer does not have the issue.

I understand that, it still sounds to me like you are organizing the
device tree around limitations of the current code. Instead the device
tree should be organized to best describe the hardware, and the code
should be adapted to support that.

Of course, if you use the flat DT layout everywhere else, I won't try to
block the reset driver because of this issue. I'm just saying nested
nodes in the DT would better describe the real control flow.

regards
Philipp
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
new file mode 100644
index 0000000..250daf2
--- /dev/null
+++ b/Documentation/devicetree/bindings/reset/hisilicon,hi3660-reset.txt
@@ -0,0 +1,51 @@ 
+Hisilicon System Reset Controller
+======================================
+
+Please also refer to reset.txt in this directory for common reset
+controller binding usage.
+
+The reset controller registers are part of the system-ctl block on
+hi3660 SoC.
+
+Required properties:
+- compatible: should be
+		 "hisilicon,hi3660-reset"
+- #reset-cells: 1, see below
+- hisi,rst-syscon: phandle of the reset's syscon.
+- hisi,reset-bits: Contains the reset control register information
+		  Should contain 2 cells for each reset exposed to
+		  consumers, defined as:
+			Cell #1 : offset from the syscon register base
+			Cell #2 : bits position of the control register
+
+Example:
+	iomcu: iomcu@ffd7e000 {
+		compatible = "hisilicon,hi3660-iomcu", "syscon";
+		reg = <0x0 0xffd7e000 0x0 0x1000>;
+	};
+
+	iomcu_rst: iomcu_rst_controller {
+		compatible = "hisilicon,hi3660-reset";
+		#reset-cells = <1>;
+		hisi,rst-syscon = <&iomcu>;
+		hisi,reset-bits = <0x20 0x8		/* 0: i2c0 */
+				   0x20 0x10		/* 1: i2c1 */
+				   0x20 0x20		/* 2: i2c2 */
+				   0x20 0x8000000>;	/* 3: i2c6 */
+	};
+
+Specifying reset lines connected to IP modules
+==============================================
+example:
+
+        i2c0: i2c@..... {
+                ...
+		resets = <&iomcu_rst 0>;
+                ...
+        };
+
+	i2c1: i2c@..... {
+                ...
+		resets = <&iomcu_rst 1>;
+                ...
+        };