[PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Claudiu Beznea]

Implement suspend/resume hooks.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---

Changes in v2:
- use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP

 drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
index 6c5708bacad8..ceaaef47f02e 100644
--- a/drivers/mtd/spi-nor/atmel-quadspi.c
+++ b/drivers/mtd/spi-nor/atmel-quadspi.c
@@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static int __maybe_unused atmel_qspi_suspend(struct device *dev)
+{
+	struct atmel_qspi *aq = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(aq->clk);
+
+	return 0;
+}
+
+static int __maybe_unused atmel_qspi_resume(struct device *dev)
+{
+	struct atmel_qspi *aq = dev_get_drvdata(dev);
+
+	clk_prepare_enable(aq->clk);
+
+	return atmel_qspi_init(aq);
+}
+
+static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
+			 atmel_qspi_resume);
 
 static const struct of_device_id atmel_qspi_dt_ids[] = {
 	{ .compatible = "atmel,sama5d2-qspi" },
@@ -749,6 +769,7 @@ static struct platform_driver atmel_qspi_driver = {
 	.driver = {
 		.name	= "atmel_qspi",
 		.of_match_table	= atmel_qspi_dt_ids,
+		.pm	= &atmel_qspi_pm_ops,
 	},
 	.probe		= atmel_qspi_probe,
 	.remove		= atmel_qspi_remove,
-- 
2.7.4

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Boris Brezillon]

Hi Claudiu,

The subject prefix should be "mtd: spi-nor: atmel-quadspi: ". No need
to send a new version just for that, I'll fix it when applying the
patch.

Looks good otherwise. Marek, any objection? If not, can you add your
Acked-by?

Thanks,

Boris

On Mon, 4 Jun 2018 11:46:33 +0300
Claudiu Beznea <claudiu.beznea@microchip.com> wrote:

> Implement suspend/resume hooks.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> ---
> 
> Changes in v2:
> - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
> 
>  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
> index 6c5708bacad8..ceaaef47f02e 100644
> --- a/drivers/mtd/spi-nor/atmel-quadspi.c
> +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
> @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
> +{
> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(aq->clk);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused atmel_qspi_resume(struct device *dev)
> +{
> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> +
> +	clk_prepare_enable(aq->clk);
> +
> +	return atmel_qspi_init(aq);
> +}
> +
> +static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
> +			 atmel_qspi_resume);
>  
>  static const struct of_device_id atmel_qspi_dt_ids[] = {
>  	{ .compatible = "atmel,sama5d2-qspi" },
> @@ -749,6 +769,7 @@ static struct platform_driver atmel_qspi_driver = {
>  	.driver = {
>  		.name	= "atmel_qspi",
>  		.of_match_table	= atmel_qspi_dt_ids,
> +		.pm	= &atmel_qspi_pm_ops,
>  	},
>  	.probe		= atmel_qspi_probe,
>  	.remove		= atmel_qspi_remove,

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Marek Vasut]

On 06/18/2018 11:49 AM, Boris Brezillon wrote:
> Hi Claudiu,
> 
> The subject prefix should be "mtd: spi-nor: atmel-quadspi: ". No need
> to send a new version just for that, I'll fix it when applying the
> patch.
> 
> Looks good otherwise. Marek, any objection? If not, can you add your
> Acked-by?

Will this work if you have ie. ubifs mounted on that QSPI NOR and you
suspect and resume during IO ? I think it would, but just curious if
there could be some problem.

> Thanks,
> 
> Boris
> 
> On Mon, 4 Jun 2018 11:46:33 +0300
> Claudiu Beznea <claudiu.beznea@microchip.com> wrote:
> 
>> Implement suspend/resume hooks.
>>
>> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
>> ---
>>
>> Changes in v2:
>> - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
>>
>>  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
>>  1 file changed, 21 insertions(+)
>>
>> diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
>> index 6c5708bacad8..ceaaef47f02e 100644
>> --- a/drivers/mtd/spi-nor/atmel-quadspi.c
>> +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
>> @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
>>  	return 0;
>>  }
>>  
>> +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
>> +{
>> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
>> +
>> +	clk_disable_unprepare(aq->clk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int __maybe_unused atmel_qspi_resume(struct device *dev)
>> +{
>> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
>> +
>> +	clk_prepare_enable(aq->clk);
>> +
>> +	return atmel_qspi_init(aq);
>> +}
>> +
>> +static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
>> +			 atmel_qspi_resume);
>>  
>>  static const struct of_device_id atmel_qspi_dt_ids[] = {
>>  	{ .compatible = "atmel,sama5d2-qspi" },
>> @@ -749,6 +769,7 @@ static struct platform_driver atmel_qspi_driver = {
>>  	.driver = {
>>  		.name	= "atmel_qspi",
>>  		.of_match_table	= atmel_qspi_dt_ids,
>> +		.pm	= &atmel_qspi_pm_ops,
>>  	},
>>  	.probe		= atmel_qspi_probe,
>>  	.remove		= atmel_qspi_remove,


-- 
Best regards,
Marek Vasut

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Claudiu Beznea]

On 18.06.2018 12:53, Marek Vasut wrote:
> On 06/18/2018 11:49 AM, Boris Brezillon wrote:
>> Hi Claudiu,
>>
>> The subject prefix should be "mtd: spi-nor: atmel-quadspi: ". No need
>> to send a new version just for that, I'll fix it when applying the
>> patch.
>>
Hi Boris,

Thank you!

>> Looks good otherwise. Marek, any objection? If not, can you add your
>> Acked-by?
> 
> Will this work if you have ie. ubifs mounted on that QSPI NOR and you
> suspect and resume during IO ? I think it would, but just curious if
> there could be some problem.

Hi Marek,

I tested only with read/writes while suspending, simple scripts, but not
having ubifs mounted on QSPI NOR. I will double check also with ubifs
mounted on QSPI NOR and come back with the results.

Thank you,
Claudiu

> 
>> Thanks,
>>
>> Boris
>>
>> On Mon, 4 Jun 2018 11:46:33 +0300
>> Claudiu Beznea <claudiu.beznea@microchip.com> wrote:
>>
>>> Implement suspend/resume hooks.
>>>
>>> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
>>> ---
>>>
>>> Changes in v2:
>>> - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
>>>
>>>  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
>>>  1 file changed, 21 insertions(+)
>>>
>>> diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
>>> index 6c5708bacad8..ceaaef47f02e 100644
>>> --- a/drivers/mtd/spi-nor/atmel-quadspi.c
>>> +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
>>> @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
>>>  	return 0;
>>>  }
>>>  
>>> +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
>>> +{
>>> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
>>> +
>>> +	clk_disable_unprepare(aq->clk);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int __maybe_unused atmel_qspi_resume(struct device *dev)
>>> +{
>>> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
>>> +
>>> +	clk_prepare_enable(aq->clk);
>>> +
>>> +	return atmel_qspi_init(aq);
>>> +}
>>> +
>>> +static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
>>> +			 atmel_qspi_resume);
>>>  
>>>  static const struct of_device_id atmel_qspi_dt_ids[] = {
>>>  	{ .compatible = "atmel,sama5d2-qspi" },
>>> @@ -749,6 +769,7 @@ static struct platform_driver atmel_qspi_driver = {
>>>  	.driver = {
>>>  		.name	= "atmel_qspi",
>>>  		.of_match_table	= atmel_qspi_dt_ids,
>>> +		.pm	= &atmel_qspi_pm_ops,
>>>  	},
>>>  	.probe		= atmel_qspi_probe,
>>>  	.remove		= atmel_qspi_remove,
> 
> 

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Marek Vasut]

On 06/18/2018 02:00 PM, Claudiu Beznea wrote:
> 
> 
> On 18.06.2018 12:53, Marek Vasut wrote:
>> On 06/18/2018 11:49 AM, Boris Brezillon wrote:
>>> Hi Claudiu,
>>>
>>> The subject prefix should be "mtd: spi-nor: atmel-quadspi: ". No need
>>> to send a new version just for that, I'll fix it when applying the
>>> patch.
>>>
> Hi Boris,
> 
> Thank you!
> 
>>> Looks good otherwise. Marek, any objection? If not, can you add your
>>> Acked-by?
>>
>> Will this work if you have ie. ubifs mounted on that QSPI NOR and you
>> suspect and resume during IO ? I think it would, but just curious if
>> there could be some problem.
> 
> Hi Marek,
> 
> I tested only with read/writes while suspending, simple scripts, but not
> having ubifs mounted on QSPI NOR. I will double check also with ubifs
> mounted on QSPI NOR and come back with the results.

Thanks. I think it's gonna be OK, but let's just be sure.
Make sure to disable 4K sector support when fiddling with UBI/UBIFS on
QSPI NOR.

-- 
Best regards,
Marek Vasut

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Claudiu Beznea]

Hi Marek,

On 19.06.2018 04:28, Marek Vasut wrote:
> On 06/18/2018 02:00 PM, Claudiu Beznea wrote:
>>
>>
>> On 18.06.2018 12:53, Marek Vasut wrote:
>>> On 06/18/2018 11:49 AM, Boris Brezillon wrote:
>>>> Hi Claudiu,
>>>>
>>>> The subject prefix should be "mtd: spi-nor: atmel-quadspi: ". No need
>>>> to send a new version just for that, I'll fix it when applying the
>>>> patch.
>>>>
>> Hi Boris,
>>
>> Thank you!
>>
>>>> Looks good otherwise. Marek, any objection? If not, can you add your
>>>> Acked-by?
>>>
>>> Will this work if you have ie. ubifs mounted on that QSPI NOR and you
>>> suspect and resume during IO ? I think it would, but just curious if
>>> there could be some problem.
>>
>> Hi Marek,
>>
>> I tested only with read/writes while suspending, simple scripts, but not
>> having ubifs mounted on QSPI NOR. I will double check also with ubifs
>> mounted on QSPI NOR and come back with the results.
> 
> Thanks. I think it's gonna be OK, but let's just be sure.
> Make sure to disable 4K sector support when fiddling with UBI/UBIFS on
> QSPI NOR.

I did the following to test this patch with ubifs:
1. disabled CONFIG_MTD_SPI_NOR_USE_4K_SECTORS and build kernel

2. create a ubifs image:
mkfs.ubifs -r /mnt/ubifs-sama5d2-rootfs -m 1 -e 65408 -c 3739 \
 -o /mnt/sama5d2-xplained-ubifs.img

3. boot the board and check partitions:
cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00010000 00010000 "at91bootstrap"
mtd1: 00010000 00010000 "bootloader env"
mtd2: 00050000 00010000 "bootloader"
mtd3: 00010000 00010000 "device tree"
mtd4: 00380000 00010000 "kernel"
mtd5: 01c00000 00010000 "rootfs"
mtd6: 00400000 00010000 "spi32766.0"

4. ubiformat /dev/mtd5
5. ubiattach -p /dev/mtd5
6. ubimkvol /dev/ubi0 -N test -s 28910336
7. ubiupdatevol /dev/ubi0_0 /sama5d2-xplained-buildroot-ubifs.img
8. mount -t ubifs ubi0:test /mnt
9. cd /mnt/; ls /mnt/
bin      lib      media    proc     sbin     usr
dev      lib32    mnt      root     sys      var
etc      linuxrc  opt      run      tmp

10. Create a file with dd on ubifs partition:
dd if=/dev/urandom of=test.bin bs=1024 count=8K

11. compute md5sum on this file:
md5sum test.bin > test.md5

12. Measure how much will take to copy that file (to be sure the copy
operation is not done before suspending):

date; cp test.bin test-pm.bin; date
Wed Jun 20 13:20:34 UTC 2018
Wed Jun 20 13:21:14 UTC 2018

13. Copy, sync, and switch to suspend-to-mem:

cp test.bin test-pm.bin &
sync &
echo mem > /sys/power/state

14. Check md5sum of test-pm.bin and compare it with md5sum of test.bin:
md5sum test-pm.bin > test-pm.md5
cat test.md5
b5338647572b9665f24c61db98601522  test.bin
cat test-pm.md5
b5338647572b9665f24c61db98601522  test-pm.bin

Please let me know if this is enough!

Thank you,
Claudiu Beznea

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Tudor Ambarus]

Hi, Claudiu,

On 06/04/2018 11:46 AM, Claudiu Beznea wrote:
> Implement suspend/resume hooks.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> ---
> 
> Changes in v2:
> - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
> 
>  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
> index 6c5708bacad8..ceaaef47f02e 100644
> --- a/drivers/mtd/spi-nor/atmel-quadspi.c
> +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
> @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
> +{
> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(aq->clk);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused atmel_qspi_resume(struct device *dev)
> +{
> +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> +
> +	clk_prepare_enable(aq->clk);

You missed to verify the return value of clk_prepare_enable. Otherwise looks
good. I've also looked over the test with suspending while copying on a ubifs
mounted on QSPI NOR, looks good too.

After checking the return value, please add:
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Best,
ta

> +
> +	return atmel_qspi_init(aq);
> +}
> +
> +static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
> +			 atmel_qspi_resume);
>  
>  static const struct of_device_id atmel_qspi_dt_ids[] = {
>  	{ .compatible = "atmel,sama5d2-qspi" },
> @@ -749,6 +769,7 @@ static struct platform_driver atmel_qspi_driver = {
>  	.driver = {
>  		.name	= "atmel_qspi",
>  		.of_match_table	= atmel_qspi_dt_ids,
> +		.pm	= &atmel_qspi_pm_ops,
>  	},
>  	.probe		= atmel_qspi_probe,
>  	.remove		= atmel_qspi_remove,
> 

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Alexandre Belloni]

On 04/07/2018 11:42:25+0300, Tudor Ambarus wrote:
> Hi, Claudiu,
> 
> On 06/04/2018 11:46 AM, Claudiu Beznea wrote:
> > Implement suspend/resume hooks.
> > 
> > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> > ---
> > 
> > Changes in v2:
> > - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
> > 
> >  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
> >  1 file changed, 21 insertions(+)
> > 
> > diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
> > index 6c5708bacad8..ceaaef47f02e 100644
> > --- a/drivers/mtd/spi-nor/atmel-quadspi.c
> > +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
> > @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
> >  	return 0;
> >  }
> >  
> > +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
> > +{
> > +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> > +
> > +	clk_disable_unprepare(aq->clk);
> > +
> > +	return 0;
> > +}
> > +
> > +static int __maybe_unused atmel_qspi_resume(struct device *dev)
> > +{
> > +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> > +
> > +	clk_prepare_enable(aq->clk);
> 
> You missed to verify the return value of clk_prepare_enable. Otherwise looks

Which will never fail, there is no point in checking it.

> good. I've also looked over the test with suspending while copying on a ubifs
> mounted on QSPI NOR, looks good too.
> 
> After checking the return value, please add:
> Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> 

-- 
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v2] mtd: atmel-quadspi: add suspend/resume hooks

[Boris Brezillon]

On Wed, 4 Jul 2018 10:57:11 +0200
Alexandre Belloni <alexandre.belloni@bootlin.com> wrote:

> On 04/07/2018 11:42:25+0300, Tudor Ambarus wrote:
> > Hi, Claudiu,
> > 
> > On 06/04/2018 11:46 AM, Claudiu Beznea wrote:  
> > > Implement suspend/resume hooks.
> > > 
> > > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>

Applied.

Thanks,

Boris

> > > ---
> > > 
> > > Changes in v2:
> > > - use __maybe_unused instead of #ifdef CONFIG_PM_SLEEP
> > > 
> > >  drivers/mtd/spi-nor/atmel-quadspi.c | 21 +++++++++++++++++++++
> > >  1 file changed, 21 insertions(+)
> > > 
> > > diff --git a/drivers/mtd/spi-nor/atmel-quadspi.c b/drivers/mtd/spi-nor/atmel-quadspi.c
> > > index 6c5708bacad8..ceaaef47f02e 100644
> > > --- a/drivers/mtd/spi-nor/atmel-quadspi.c
> > > +++ b/drivers/mtd/spi-nor/atmel-quadspi.c
> > > @@ -737,6 +737,26 @@ static int atmel_qspi_remove(struct platform_device *pdev)
> > >  	return 0;
> > >  }
> > >  
> > > +static int __maybe_unused atmel_qspi_suspend(struct device *dev)
> > > +{
> > > +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> > > +
> > > +	clk_disable_unprepare(aq->clk);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int __maybe_unused atmel_qspi_resume(struct device *dev)
> > > +{
> > > +	struct atmel_qspi *aq = dev_get_drvdata(dev);
> > > +
> > > +	clk_prepare_enable(aq->clk);  
> > 
> > You missed to verify the return value of clk_prepare_enable. Otherwise looks  
> 
> Which will never fail, there is no point in checking it.
> 
> > good. I've also looked over the test with suspending while copying on a ubifs
> > mounted on QSPI NOR, looks good too.
> > 
> > After checking the return value, please add:
> > Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> >   
>