diff mbox series

[net-next,1/3] dt-bindings: net: fsl,fec: add "fsl,wakeup-irq" property

Message ID 20210805074615.29096-2-qiangqing.zhang@nxp.com
State New
Headers show
Series net: fec: add support to select wakeup irq source | expand

Commit Message

Joakim Zhang Aug. 5, 2021, 7:46 a.m. UTC
Add "fsl,wakeup-irq" property for FEC controller to select wakeup irq
source.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
---
 Documentation/devicetree/bindings/net/fsl,fec.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

Comments

Joakim Zhang Aug. 9, 2021, 5:08 a.m. UTC | #1
Hi Florian,

> -----Original Message-----

> From: Florian Fainelli <f.fainelli@gmail.com>

> Sent: 2021年8月5日 17:18

> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;

> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;

> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch

> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;

> netdev@vger.kernel.org; devicetree@vger.kernel.org;

> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org

> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add "fsl,

> wakeup-irq" property

> 

> 

> 

> On 8/5/2021 12:46 AM, Joakim Zhang wrote:

> > Add "fsl,wakeup-irq" property for FEC controller to select wakeup irq

> > source.

> >

> > Signed-off-by: Fugang Duan <fugang.duan@nxp.com>

> > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>

> 

> Why are not you making use of the standard interrupts-extended property

> which allows different interrupt lines to be originating from different interrupt

> controllers, e.g.:

> 

> interrupts-extended = <&gic GIC_SPI 112 4>, <&wakeup_intc 0>;


Thanks.

AFAIK, interrupts-extended should be used instead of interrupts when a device is connected to multiple interrupt controllers
as it encodes a parent phandle with each interrupt specifier. However, for FEC controller, all interrupt lines are originating from
the same interrupt controllers.

1) FEC controller has up to 4 interrupt lines and all of these are routed to GIC interrupt controller.
2) FEC has a wakeup interrupt signal and always are mixed with other interrupt signals, and then output to one interrupt line.
3) For legacy SoCs, wakeup interrupt are mixed to int0 line, but for i.MX8M serials, are mixed to int2 line.
4) Now driver treat int0 as the wakeup source by default, it is broken for i.MX8M.

Best Regards,
Joakim Zhang
> --

> Florian
Florian Fainelli Aug. 9, 2021, 6:39 p.m. UTC | #2
On 8/8/2021 10:08 PM, Joakim Zhang wrote:
> 
> Hi Florian,
> 
>> -----Original Message-----
>> From: Florian Fainelli <f.fainelli@gmail.com>
>> Sent: 2021年8月5日 17:18
>> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;
>> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;
>> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch
>> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;
>> netdev@vger.kernel.org; devicetree@vger.kernel.org;
>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
>> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add "fsl,
>> wakeup-irq" property
>>
>>
>>
>> On 8/5/2021 12:46 AM, Joakim Zhang wrote:
>>> Add "fsl,wakeup-irq" property for FEC controller to select wakeup irq
>>> source.
>>>
>>> Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
>>> Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
>>
>> Why are not you making use of the standard interrupts-extended property
>> which allows different interrupt lines to be originating from different interrupt
>> controllers, e.g.:
>>
>> interrupts-extended = <&gic GIC_SPI 112 4>, <&wakeup_intc 0>;
> 
> Thanks.
> 
> AFAIK, interrupts-extended should be used instead of interrupts when a device is connected to multiple interrupt controllers
> as it encodes a parent phandle with each interrupt specifier. However, for FEC controller, all interrupt lines are originating from
> the same interrupt controllers.

OK, so why this custom property then?

> 
> 1) FEC controller has up to 4 interrupt lines and all of these are routed to GIC interrupt controller.
> 2) FEC has a wakeup interrupt signal and always are mixed with other interrupt signals, and then output to one interrupt line.
> 3) For legacy SoCs, wakeup interrupt are mixed to int0 line, but for i.MX8M serials, are mixed to int2 line.
> 4) Now driver treat int0 as the wakeup source by default, it is broken for i.MX8M.

I don't really know what to make of your response, it seems to me that 
you are carrying some legacy Device Tree properties that were invented 
when interrupts-extended did not exist and we did not know any better.
Andrew Lunn Aug. 10, 2021, 2:32 p.m. UTC | #3
> > > 1) FEC controller has up to 4 interrupt lines and all of these are routed to GIC
> > interrupt controller.
> > > 2) FEC has a wakeup interrupt signal and always are mixed with other
> > interrupt signals, and then output to one interrupt line.
> > > 3) For legacy SoCs, wakeup interrupt are mixed to int0 line, but for i.MX8M
> > serials, are mixed to int2 line.

So you need to know which of the interrupts listed is the wake up
interrupt.

I can see a few ways to do this:

The FEC driver already has quirks. Add a quirk to fec_imx8mq_info and
fec_imx8qm_info to indicate these should use int2.

or

Documentation/devicetree/bindings/interrupt-controller/interrupts.txt 

  b) two cells
  ------------
  The #interrupt-cells property is set to 2 and the first cell defines the
  index of the interrupt within the controller, while the second cell is used
  to specify any of the following flags:
    - bits[3:0] trigger type and level flags
        1 = low-to-high edge triggered
        2 = high-to-low edge triggered
        4 = active high level-sensitive
        8 = active low level-sensitive

You could add

       18 = wakeup source

and extend to core to either do all the work for you, or tell you this
interrupt is flagged as being a wakeup source. This solution has the
advantage of it should be usable in other drivers.

	  Andrew
Joakim Zhang Aug. 11, 2021, 8:06 a.m. UTC | #4
> -----Original Message-----

> From: Florian Fainelli <f.fainelli@gmail.com>

> Sent: 2021年8月11日 1:45

> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;

> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;

> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch

> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;

> netdev@vger.kernel.org; devicetree@vger.kernel.org;

> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org

> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add "fsl,

> wakeup-irq" property

> 

> 

> 

> On 8/9/2021 7:21 PM, Joakim Zhang wrote:

> >

> > Hi Florian,

> >

> >> -----Original Message-----

> >> From: Florian Fainelli <f.fainelli@gmail.com>

> >> Sent: 2021年8月10日 2:40

> >> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;

> >> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;

> >> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch

> >> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;

> >> netdev@vger.kernel.org; devicetree@vger.kernel.org;

> >> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org

> >> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add

> >> "fsl, wakeup-irq" property

> >>

> >>

> >>

> >> On 8/8/2021 10:08 PM, Joakim Zhang wrote:

> >>>

> >>> Hi Florian,

> >>>

> >>>> -----Original Message-----

> >>>> From: Florian Fainelli <f.fainelli@gmail.com>

> >>>> Sent: 2021年8月5日 17:18

> >>>> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;

> >>>> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;

> >>>> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch

> >>>> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;

> >>>> netdev@vger.kernel.org; devicetree@vger.kernel.org;

> >>>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org

> >>>> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add

> >>>> "fsl, wakeup-irq" property

> >>>>

> >>>>

> >>>>

> >>>> On 8/5/2021 12:46 AM, Joakim Zhang wrote:

> >>>>> Add "fsl,wakeup-irq" property for FEC controller to select wakeup

> >>>>> irq source.

> >>>>>

> >>>>> Signed-off-by: Fugang Duan <fugang.duan@nxp.com>

> >>>>> Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>

> >>>>

> >>>> Why are not you making use of the standard interrupts-extended

> >>>> property which allows different interrupt lines to be originating

> >>>> from different interrupt controllers, e.g.:

> >>>>

> >>>> interrupts-extended = <&gic GIC_SPI 112 4>, <&wakeup_intc 0>;

> >>>

> >>> Thanks.

> >>>

> >>> AFAIK, interrupts-extended should be used instead of interrupts when

> >>> a device is connected to multiple interrupt controllers as it

> >>> encodes a parent phandle with each interrupt specifier. However, for

> >>> FEC controller, all

> >> interrupt lines are originating from the same interrupt controllers.

> >>

> >> OK, so why this custom property then?

> >>

> >>>

> >>> 1) FEC controller has up to 4 interrupt lines and all of these are

> >>> routed to GIC

> >> interrupt controller.

> >>> 2) FEC has a wakeup interrupt signal and always are mixed with other

> >> interrupt signals, and then output to one interrupt line.

> >>> 3) For legacy SoCs, wakeup interrupt are mixed to int0 line, but for

> >>> i.MX8M

> >> serials, are mixed to int2 line.

> >>> 4) Now driver treat int0 as the wakeup source by default, it is

> >>> broken for

> >> i.MX8M.

> >>

> >> I don't really know what to make of your response, it seems to me

> >> that you are carrying some legacy Device Tree properties that were

> >> invented when interrupts-extended did not exist and we did not know any

> better.

> >

> > As I described in former mail, it is not related to interrupts-extended

> property.

> >

> > Let's take a look, e.g.

> >

> > 1) arch/arm/boot/dts/imx7d.dtsi

> > interrupts = <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>,

> > 		<GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>,

> > 		<GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>,

> > 		<GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;

> > interrupt-names = "int0", "int1", "int2", "pps";

> >

> > For these 4 interrupts are originating from GIC interrupt controller,

> > "int0" for queue 0 and other interrupt signals, containing wakeup; "int1" for

> queue 1; "int2" for queue 2.

> >

> > 2) arch/arm64/boot/dts/freescale/imx8mq.dtsi

> > interrupts = <GIC_SPI 118 IRQ_TYPE_LEVEL_HIGH>,

> > 	<GIC_SPI 119 IRQ_TYPE_LEVEL_HIGH>,

> > 	<GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>,

> > 	<GIC_SPI 121 IRQ_TYPE_LEVEL_HIGH>;

> > interrupt-names = "int0", "int1", "int2", "pps";

> >

> > For these 4 interrupts are also originating from GIC interrupt

> > controller, "int0" for queue 0; "int1" for queue 1; "int2" for queue 2 and other

> interrupt signals, containing wakeup.

> >

> > If we want to use WoL feature, we need invoke enable_irq_wake() to let

> > this specific interrupt line be a wakeup source. For FEC driver now,

> > it treats "int0" as wakeup interrupt by default. Obviously it's not fine for

> i.MX8M serials, since SoC mix wakeup interrupt signal into "int2", so I add this

> "fsl,wakeup-irq" custom property to indicate which interrupt line contains

> wakeup signal.

> >

> > Not sure if I have explained it clearly enough, from my point of view, I think

> interrupts-extended property can't fix this issue, right?

> 

> This is clearer, and indeed interrupts-extended won't fix that, however it seems

> to me that this is a problem that ought to be fixed at the interrupt

> controller/irq_chip level which should know and be told which interrupt lines

> can be made wake-up interrupts or not. From there on, the driver can test with

> enable_irq_wake() whether this has a chance of working or not.


How can we test with enable_irq_wake()? I agree that interrupt controller can recognize
wakeup interrupt is better. 

> It seems to me that the 'fsl,wakeup-irq' property ought to be within the

> interrupt controller Device Tree node (where it would be easier to validate that

> the specific interrupt line is correct) as opposed to within the consumer (FEC)

> Device Tree node.


Not quite understand, could you explain more?

> >

> > If there is any common properties can be used for it, please let me know. Or

> any other better solutions also be appreciated. Thanks.

> 

> There is a standard 'wakeup-source' boolean property that can be added

> to any Device Tree node to indicate it can be a wake-up source, but what

> you need here is a bitmask, so introducing a custom property may be

> appropriate here.


Yes, I know 'wakeup-source' boolean property that identify this DEVICE
can be a wakeup source, it's not related to interrupt.

Best Regards,
Joakim Zhang
> --

> Florian
Florian Fainelli Aug. 12, 2021, 9:46 a.m. UTC | #5
On 8/11/2021 1:06 AM, Joakim Zhang wrote:
> 
>> -----Original Message-----
>> From: Florian Fainelli <f.fainelli@gmail.com>
>> Sent: 2021年8月11日 1:45
>> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;
>> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;
>> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch
>> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;
>> netdev@vger.kernel.org; devicetree@vger.kernel.org;
>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
>> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add "fsl,
>> wakeup-irq" property
>>
>>
>>
>> On 8/9/2021 7:21 PM, Joakim Zhang wrote:
>>>
>>> Hi Florian,
>>>
>>>> -----Original Message-----
>>>> From: Florian Fainelli <f.fainelli@gmail.com>
>>>> Sent: 2021年8月10日 2:40
>>>> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;
>>>> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;
>>>> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch
>>>> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;
>>>> netdev@vger.kernel.org; devicetree@vger.kernel.org;
>>>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
>>>> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add
>>>> "fsl, wakeup-irq" property
>>>>
>>>>
>>>>
>>>> On 8/8/2021 10:08 PM, Joakim Zhang wrote:
>>>>>
>>>>> Hi Florian,
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Florian Fainelli <f.fainelli@gmail.com>
>>>>>> Sent: 2021年8月5日 17:18
>>>>>> To: Joakim Zhang <qiangqing.zhang@nxp.com>; davem@davemloft.net;
>>>>>> kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;
>>>>>> s.hauer@pengutronix.de; festevam@gmail.com; andrew@lunn.ch
>>>>>> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>;
>>>>>> netdev@vger.kernel.org; devicetree@vger.kernel.org;
>>>>>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
>>>>>> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add
>>>>>> "fsl, wakeup-irq" property
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 8/5/2021 12:46 AM, Joakim Zhang wrote:
>>>>>>> Add "fsl,wakeup-irq" property for FEC controller to select wakeup
>>>>>>> irq source.
>>>>>>>
>>>>>>> Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
>>>>>>> Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
>>>>>>
>>>>>> Why are not you making use of the standard interrupts-extended
>>>>>> property which allows different interrupt lines to be originating
>>>>>> from different interrupt controllers, e.g.:
>>>>>>
>>>>>> interrupts-extended = <&gic GIC_SPI 112 4>, <&wakeup_intc 0>;
>>>>>
>>>>> Thanks.
>>>>>
>>>>> AFAIK, interrupts-extended should be used instead of interrupts when
>>>>> a device is connected to multiple interrupt controllers as it
>>>>> encodes a parent phandle with each interrupt specifier. However, for
>>>>> FEC controller, all
>>>> interrupt lines are originating from the same interrupt controllers.
>>>>
>>>> OK, so why this custom property then?
>>>>
>>>>>
>>>>> 1) FEC controller has up to 4 interrupt lines and all of these are
>>>>> routed to GIC
>>>> interrupt controller.
>>>>> 2) FEC has a wakeup interrupt signal and always are mixed with other
>>>> interrupt signals, and then output to one interrupt line.
>>>>> 3) For legacy SoCs, wakeup interrupt are mixed to int0 line, but for
>>>>> i.MX8M
>>>> serials, are mixed to int2 line.
>>>>> 4) Now driver treat int0 as the wakeup source by default, it is
>>>>> broken for
>>>> i.MX8M.
>>>>
>>>> I don't really know what to make of your response, it seems to me
>>>> that you are carrying some legacy Device Tree properties that were
>>>> invented when interrupts-extended did not exist and we did not know any
>> better.
>>>
>>> As I described in former mail, it is not related to interrupts-extended
>> property.
>>>
>>> Let's take a look, e.g.
>>>
>>> 1) arch/arm/boot/dts/imx7d.dtsi
>>> interrupts = <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>,
>>> 		<GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>,
>>> 		<GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>,
>>> 		<GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;
>>> interrupt-names = "int0", "int1", "int2", "pps";
>>>
>>> For these 4 interrupts are originating from GIC interrupt controller,
>>> "int0" for queue 0 and other interrupt signals, containing wakeup; "int1" for
>> queue 1; "int2" for queue 2.
>>>
>>> 2) arch/arm64/boot/dts/freescale/imx8mq.dtsi
>>> interrupts = <GIC_SPI 118 IRQ_TYPE_LEVEL_HIGH>,
>>> 	<GIC_SPI 119 IRQ_TYPE_LEVEL_HIGH>,
>>> 	<GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>,
>>> 	<GIC_SPI 121 IRQ_TYPE_LEVEL_HIGH>;
>>> interrupt-names = "int0", "int1", "int2", "pps";
>>>
>>> For these 4 interrupts are also originating from GIC interrupt
>>> controller, "int0" for queue 0; "int1" for queue 1; "int2" for queue 2 and other
>> interrupt signals, containing wakeup.
>>>
>>> If we want to use WoL feature, we need invoke enable_irq_wake() to let
>>> this specific interrupt line be a wakeup source. For FEC driver now,
>>> it treats "int0" as wakeup interrupt by default. Obviously it's not fine for
>> i.MX8M serials, since SoC mix wakeup interrupt signal into "int2", so I add this
>> "fsl,wakeup-irq" custom property to indicate which interrupt line contains
>> wakeup signal.
>>>
>>> Not sure if I have explained it clearly enough, from my point of view, I think
>> interrupts-extended property can't fix this issue, right?
>>
>> This is clearer, and indeed interrupts-extended won't fix that, however it seems
>> to me that this is a problem that ought to be fixed at the interrupt
>> controller/irq_chip level which should know and be told which interrupt lines
>> can be made wake-up interrupts or not. From there on, the driver can test with
>> enable_irq_wake() whether this has a chance of working or not.
> 
> How can we test with enable_irq_wake()? I agree that interrupt controller can recognize
> wakeup interrupt is better.

If enable_irq_wake() returns -ENOTSUPP you would know that wake-up for 
that interrupt controller's line is not capable of wake-up?

> 
>> It seems to me that the 'fsl,wakeup-irq' property ought to be within the
>> interrupt controller Device Tree node (where it would be easier to validate that
>> the specific interrupt line is correct) as opposed to within the consumer (FEC)
>> Device Tree node.
> 
> Not quite understand, could you explain more?

What I mean is that if you need to express which interrupt lines within 
an interrupt controller are capable of wake-up, then there should be a 
property that tells us that and that property needs to be within the 
interrupt controller, not within the consumer of that interrupt since 
the consumer has no idea how the system is wired up. Andrew's suggestion 
is sort of the same thing, except that it punts the responsibility of 
specifying the interrupt's capability towards the consumer of that 
interrupt.
Joakim Zhang Aug. 16, 2021, 6:48 a.m. UTC | #6
> -----Original Message-----

> From: Rob Herring <robh@kernel.org>

> Sent: 2021年8月14日 2:23

> To: Joakim Zhang <qiangqing.zhang@nxp.com>

> Cc: Andrew Lunn <andrew@lunn.ch>; Florian Fainelli <f.fainelli@gmail.com>;

> davem@davemloft.net; kuba@kernel.org; shawnguo@kernel.org;

> s.hauer@pengutronix.de; festevam@gmail.com; kernel@pengutronix.de;

> dl-linux-imx <linux-imx@nxp.com>; netdev@vger.kernel.org;

> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org;

> linux-arm-kernel@lists.infradead.org

> Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add "fsl,

> wakeup-irq" property

> 

> On Wed, Aug 11, 2021 at 07:57:46AM +0000, Joakim Zhang wrote:

> >

> > Hi Andrew,

> >

> > > -----Original Message-----

> > > From: Andrew Lunn <andrew@lunn.ch>

> > > Sent: 2021年8月10日 22:33

> > > To: Joakim Zhang <qiangqing.zhang@nxp.com>

> > > Cc: Florian Fainelli <f.fainelli@gmail.com>; davem@davemloft.net;

> > > kuba@kernel.org; robh+dt@kernel.org; shawnguo@kernel.org;

> > > s.hauer@pengutronix.de; festevam@gmail.com; kernel@pengutronix.de;

> > > dl-linux-imx <linux-imx@nxp.com>; netdev@vger.kernel.org;

> > > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org;

> > > linux-arm-kernel@lists.infradead.org

> > > Subject: Re: [PATCH net-next 1/3] dt-bindings: net: fsl, fec: add

> > > "fsl, wakeup-irq" property

> > >

> > > > > > 1) FEC controller has up to 4 interrupt lines and all of these

> > > > > > are routed to GIC

> > > > > interrupt controller.

> > > > > > 2) FEC has a wakeup interrupt signal and always are mixed with

> > > > > > other

> > > > > interrupt signals, and then output to one interrupt line.

> > > > > > 3) For legacy SoCs, wakeup interrupt are mixed to int0 line,

> > > > > > but for i.MX8M

> > > > > serials, are mixed to int2 line.

> > >

> > > So you need to know which of the interrupts listed is the wake up interrupt.

> 

> We already have a way to do this by using 'wakeup' for the interrupt-names

> entry. But I guess that ship has sailed here and that wouldn't work well if not

> just a wakeup source (though you could repeat an interrupt line that's the

> wakeup source).


Yes, I am not sure whether it's a common solution, such as:
interrupts = <GIC_SPI 118 IRQ_TYPE_LEVEL_HIGH>,
		<GIC_SPI 119 IRQ_TYPE_LEVEL_HIGH>,
		<GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>,
		<GIC_SPI 121 IRQ_TYPE_LEVEL_HIGH>,
		<GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>,
interrupt-names = "int0", "int1", "int2", "pps", "wakeup";

Where we repeat interrupt 120 for both "int2" and "wakeup", does you mean this?

> > >

> > > I can see a few ways to do this:

> > >

> > > The FEC driver already has quirks. Add a quirk to fec_imx8mq_info

> > > and fec_imx8qm_info to indicate these should use int2.

> 

> Bingo!

> 

> Note that if the device is wakeup capable, it should have a 'wakeup-source'

> property in this case.

> 

> > >

> > > or

> > >

> > > Documentation/devicetree/bindings/interrupt-controller/interrupts.tx

> > > t

> > >

> > >   b) two cells

> > >   ------------

> > >   The #interrupt-cells property is set to 2 and the first cell defines the

> > >   index of the interrupt within the controller, while the second cell is used

> > >   to specify any of the following flags:

> > >     - bits[3:0] trigger type and level flags

> > >         1 = low-to-high edge triggered

> > >         2 = high-to-low edge triggered

> > >         4 = active high level-sensitive

> > >         8 = active low level-sensitive

> > >

> > > You could add

> > >

> > >        18 = wakeup source

> 

> I'd be okay with this (though it should be a power of 2 number).

> 

> > >

> > > and extend to core to either do all the work for you, or tell you

> > > this interrupt is flagged as being a wakeup source. This solution

> > > has the advantage of it should be usable in other drivers.

> 

> Another option is couldn't you just enable all the interrupts as wakeup sources?

> Presumably, only one of them would trigger a wakeup.


Yes, another solution, I thought it but not implemented it as we had better let users know which
interrupt is wakeup capable.

Best Regards,
Joakim Zhang
> >

> > Thanks a lot for your comments first!

> >

> > I just look into the irq code, if we extend bit[5] to carry wakeup

> > info ( due to bit[4] is used for IRQ_TYPE_PROBE), then configure it in

> > the TYPE field of 'interrupts' property, so that interrupt controller would know

> which interrupt is wakeup capable.

> > I think there is no much work core would do, may just set this

> > interrupt wakup capable. Another functionality is driver side get this info to

> identify which mixed interrupt has wakeup capability, we can export symbol

> from kernel/irq/irqdomain.c.

> >

> > The intention is to let driver know which interrupt is wakeup capable,

> > I would choose to provider this in specific driver, instead of interrupt

> controller, it seems to me that others may all choose this solution for wakeup

> mixed interrupt.

> >

> > So I would prefer solution 1, it's easier and under-control. I can have a try if

> you strongly recommend solution 2.

> >

> > Best Regards,

> > Joakim Zhang

> > > 	  Andrew
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/net/fsl,fec.yaml b/Documentation/devicetree/bindings/net/fsl,fec.yaml
index eca41443fcce..d83f2103c1e6 100644
--- a/Documentation/devicetree/bindings/net/fsl,fec.yaml
+++ b/Documentation/devicetree/bindings/net/fsl,fec.yaml
@@ -164,6 +164,13 @@  properties:
       req_gpr is the gpr register offset for ENET stop request.
       req_bit is the gpr bit offset for ENET stop request.
 
+  fsl,wakeup-irq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      The property defines the wakeup irq index in enet irq source, the default
+      value is 0 if not specified.
+    enum: [0, 1, 2, 3]
+
   mdio:
     type: object
     description: