[v3] Add suspend to ram support for PCIe on J7200

[PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Thomas Richard 1 year, 12 months ago

Add suspend and resume support.

The already_configured flag is cleared during the suspend stage to force
the PHY initialization during the resume stage.

Based on the work of Théo Lebrun <theo.lebrun@bootlin.com>

Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/phy/cadence/phy-cadence-torrent.c | 54 +++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
index 52cadca4c07b..f8945a11e7ca 100644
--- a/drivers/phy/cadence/phy-cadence-torrent.c
+++ b/drivers/phy/cadence/phy-cadence-torrent.c
@@ -3005,6 +3005,59 @@ static void cdns_torrent_phy_remove(struct platform_device *pdev)
 	cdns_torrent_clk_cleanup(cdns_phy);
 }
 
+static int cdns_torrent_phy_suspend_noirq(struct device *dev)
+{
+	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
+	int i;
+
+	reset_control_assert(cdns_phy->phy_rst);
+	reset_control_assert(cdns_phy->apb_rst);
+	for (i = 0; i < cdns_phy->nsubnodes; i++)
+		reset_control_assert(cdns_phy->phys[i].lnk_rst);
+
+	if (cdns_phy->already_configured)
+		cdns_phy->already_configured = 0;
+	else
+		clk_disable_unprepare(cdns_phy->clk);
+
+	return 0;
+}
+
+static int cdns_torrent_phy_resume_noirq(struct device *dev)
+{
+	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
+	int node = cdns_phy->nsubnodes;
+	int ret, i;
+
+	ret = cdns_torrent_clk(cdns_phy);
+	if (ret)
+		goto clk_cleanup;
+
+	/* Enable APB */
+	reset_control_deassert(cdns_phy->apb_rst);
+
+	if (cdns_phy->nsubnodes > 1) {
+		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
+		if (ret)
+			goto put_lnk_rst;
+	}
+
+	return 0;
+
+put_lnk_rst:
+	for (i = 0; i < node; i++)
+		reset_control_assert(cdns_phy->phys[i].lnk_rst);
+	reset_control_assert(cdns_phy->apb_rst);
+	clk_disable_unprepare(cdns_phy->clk);
+clk_cleanup:
+	cdns_torrent_clk_cleanup(cdns_phy);
+	return ret;
+}
+
+static DEFINE_NOIRQ_DEV_PM_OPS(cdns_torrent_phy_pm_ops,
+			       cdns_torrent_phy_suspend_noirq,
+			       cdns_torrent_phy_resume_noirq);
+
 /* USB and DP link configuration */
 static struct cdns_reg_pairs usb_dp_link_cmn_regs[] = {
 	{0x0002, PHY_PLL_CFG},
@@ -4576,6 +4629,7 @@ static struct platform_driver cdns_torrent_phy_driver = {
 	.driver = {
 		.name	= "cdns-torrent-phy",
 		.of_match_table	= cdns_torrent_phy_of_match,
+		.pm	= pm_sleep_ptr(&cdns_torrent_phy_pm_ops),
 	}
 };
 module_platform_driver(cdns_torrent_phy_driver);

-- 
2.39.2

Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Philipp Zabel 1 year, 11 months ago

On Do, 2024-02-15 at 16:17 +0100, Thomas Richard wrote:
> Add suspend and resume support.
> 
> The already_configured flag is cleared during the suspend stage to force
> the PHY initialization during the resume stage.
> 
> Based on the work of Théo Lebrun <theo.lebrun@bootlin.com>
> 
> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
> ---
>  drivers/phy/cadence/phy-cadence-torrent.c | 54 +++++++++++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
> 
> diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
> index 52cadca4c07b..f8945a11e7ca 100644
> --- a/drivers/phy/cadence/phy-cadence-torrent.c
> +++ b/drivers/phy/cadence/phy-cadence-torrent.c
> @@ -3005,6 +3005,59 @@ static void cdns_torrent_phy_remove(struct platform_device *pdev)
>  	cdns_torrent_clk_cleanup(cdns_phy);
>  }
>  
> +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
> +{
> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> +	int i;
> +
> +	reset_control_assert(cdns_phy->phy_rst);
> +	reset_control_assert(cdns_phy->apb_rst);
> +	for (i = 0; i < cdns_phy->nsubnodes; i++)
> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> +
> +	if (cdns_phy->already_configured)
> +		cdns_phy->already_configured = 0;
> +	else
> +		clk_disable_unprepare(cdns_phy->clk);
> +
> +	return 0;
> +}
> +
> +static int cdns_torrent_phy_resume_noirq(struct device *dev)
> +{
> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> +	int node = cdns_phy->nsubnodes;
> +	int ret, i;
> +
> +	ret = cdns_torrent_clk(cdns_phy);
> +	if (ret)
> +		goto clk_cleanup;
> +
> +	/* Enable APB */
> +	reset_control_deassert(cdns_phy->apb_rst);
> +
> +	if (cdns_phy->nsubnodes > 1) {
> +		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
> +		if (ret)
> +			goto put_lnk_rst;
> +	}
> +
> +	return 0;
> +
> +put_lnk_rst:
> +	for (i = 0; i < node; i++)
> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);

The same cleanup is found in probe. Would it be cleaner to move this
into cdns_torrent_phy_configure_multilink() instead of duplicating it
here?

> +	reset_control_assert(cdns_phy->apb_rst);
> +	clk_disable_unprepare(cdns_phy->clk);
> +clk_cleanup:
> +	cdns_torrent_clk_cleanup(cdns_phy);

This calls of_clk_del_provider(), seems misplaced here.

regards
Philipp

Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Thomas Richard 1 year, 11 months ago

On 2/21/24 14:09, Philipp Zabel wrote:
> On Do, 2024-02-15 at 16:17 +0100, Thomas Richard wrote:
>> Add suspend and resume support.
>>
>> The already_configured flag is cleared during the suspend stage to force
>> the PHY initialization during the resume stage.
>>
>> Based on the work of Théo Lebrun <theo.lebrun@bootlin.com>
>>
>> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
>> ---
>>  drivers/phy/cadence/phy-cadence-torrent.c | 54 +++++++++++++++++++++++++++++++
>>  1 file changed, 54 insertions(+)
>>
>> diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
>> index 52cadca4c07b..f8945a11e7ca 100644
>> --- a/drivers/phy/cadence/phy-cadence-torrent.c
>> +++ b/drivers/phy/cadence/phy-cadence-torrent.c
>> @@ -3005,6 +3005,59 @@ static void cdns_torrent_phy_remove(struct platform_device *pdev)
>>  	cdns_torrent_clk_cleanup(cdns_phy);
>>  }
>>  
>> +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
>> +{
>> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
>> +	int i;
>> +
>> +	reset_control_assert(cdns_phy->phy_rst);
>> +	reset_control_assert(cdns_phy->apb_rst);
>> +	for (i = 0; i < cdns_phy->nsubnodes; i++)
>> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
>> +
>> +	if (cdns_phy->already_configured)
>> +		cdns_phy->already_configured = 0;
>> +	else
>> +		clk_disable_unprepare(cdns_phy->clk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int cdns_torrent_phy_resume_noirq(struct device *dev)
>> +{
>> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
>> +	int node = cdns_phy->nsubnodes;
>> +	int ret, i;
>> +
>> +	ret = cdns_torrent_clk(cdns_phy);
>> +	if (ret)
>> +		goto clk_cleanup;
>> +
>> +	/* Enable APB */
>> +	reset_control_deassert(cdns_phy->apb_rst);
>> +
>> +	if (cdns_phy->nsubnodes > 1) {
>> +		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
>> +		if (ret)
>> +			goto put_lnk_rst;
>> +	}
>> +
>> +	return 0;
>> +
>> +put_lnk_rst:
>> +	for (i = 0; i < node; i++)
>> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> 
> The same cleanup is found in probe. Would it be cleaner to move this
> into cdns_torrent_phy_configure_multilink() instead of duplicating it
> here?

Hello Philipp,

Yes I could, but from my point of view, it would not be cleaner.
This cleanup is called from many places in the probe:
-
https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2948
-
https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2954
-
https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2960

If I add this cleanup in cdns_torrent_phy_configure_multilink(), yes I
could remove it from cdns_torrent_phy_resume_noirq(), but I should keep
it in the probe. And I should modify the probe to jump to clk_cleanup if
cdns_torrent_phy_configure_multilink() fails.

> 
>> +	reset_control_assert(cdns_phy->apb_rst);
>> +	clk_disable_unprepare(cdns_phy->clk);
>> +clk_cleanup:
>> +	cdns_torrent_clk_cleanup(cdns_phy);
> 
> This calls of_clk_del_provider(), seems misplaced here.

Yes you're right, it's called in cdns_torrent_phy_remove().
So I should not call it in the resume callback, this will cause some
issues during the remove.

Regards,

-- 
Thomas Richard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Philipp Zabel 1 year, 11 months ago

On Mi, 2024-02-21 at 14:41 +0100, Thomas Richard wrote:
> On 2/21/24 14:09, Philipp Zabel wrote:
> > On Do, 2024-02-15 at 16:17 +0100, Thomas Richard wrote:
> > > Add suspend and resume support.
> > > 
> > > The already_configured flag is cleared during the suspend stage to force
> > > the PHY initialization during the resume stage.
> > > 
> > > Based on the work of Théo Lebrun <theo.lebrun@bootlin.com>
> > > 
> > > Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
> > > ---
> > >  drivers/phy/cadence/phy-cadence-torrent.c | 54 +++++++++++++++++++++++++++++++
> > >  1 file changed, 54 insertions(+)
> > > 
> > > diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
> > > index 52cadca4c07b..f8945a11e7ca 100644
> > > --- a/drivers/phy/cadence/phy-cadence-torrent.c
> > > +++ b/drivers/phy/cadence/phy-cadence-torrent.c
> > > @@ -3005,6 +3005,59 @@ static void cdns_torrent_phy_remove(struct platform_device *pdev)
> > >  	cdns_torrent_clk_cleanup(cdns_phy);
> > >  }
> > >  
> > > +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
> > > +{
> > > +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> > > +	int i;
> > > +
> > > +	reset_control_assert(cdns_phy->phy_rst);
> > > +	reset_control_assert(cdns_phy->apb_rst);
> > > +	for (i = 0; i < cdns_phy->nsubnodes; i++)
> > > +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> > > +
> > > +	if (cdns_phy->already_configured)
> > > +		cdns_phy->already_configured = 0;
> > > +	else
> > > +		clk_disable_unprepare(cdns_phy->clk);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int cdns_torrent_phy_resume_noirq(struct device *dev)
> > > +{
> > > +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> > > +	int node = cdns_phy->nsubnodes;
> > > +	int ret, i;
> > > +
> > > +	ret = cdns_torrent_clk(cdns_phy);
> > > +	if (ret)
> > > +		goto clk_cleanup;
> > > +
> > > +	/* Enable APB */
> > > +	reset_control_deassert(cdns_phy->apb_rst);
> > > +
> > > +	if (cdns_phy->nsubnodes > 1) {
> > > +		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
> > > +		if (ret)
> > > +			goto put_lnk_rst;
> > > +	}
> > > +
> > > +	return 0;
> > > +
> > > +put_lnk_rst:
> > > +	for (i = 0; i < node; i++)
> > > +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> > 
> > The same cleanup is found in probe. Would it be cleaner to move this
> > into cdns_torrent_phy_configure_multilink() instead of duplicating it
> > here?
> 
> Hello Philipp,
> 
> Yes I could, but from my point of view, it would not be cleaner.
> This cleanup is called from many places in the probe:
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2948
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2954
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-cadence-torrent.c#L2960
>
> If I add this cleanup in cdns_torrent_phy_configure_multilink(), yes I
> could remove it from cdns_torrent_phy_resume_noirq(), but I should keep
> it in the probe. And I should modify the probe to jump to clk_cleanup if
> cdns_torrent_phy_configure_multilink() fails.

I see it now. If it can't be consolidated, it's not useful to move it
around.

> 
regards
Philipp

Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Andy Shevchenko 1 year, 12 months ago

On Thu, Feb 15, 2024 at 04:17:59PM +0100, Thomas Richard wrote:
> Add suspend and resume support.
> 
> The already_configured flag is cleared during the suspend stage to force
> the PHY initialization during the resume stage.

> Based on the work of Théo Lebrun <theo.lebrun@bootlin.com>

SoB/Co-developed-by ?

...

> +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
> +{
> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> +	int i;

Why signed?

> +	reset_control_assert(cdns_phy->phy_rst);
> +	reset_control_assert(cdns_phy->apb_rst);
> +	for (i = 0; i < cdns_phy->nsubnodes; i++)
> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> +
> +	if (cdns_phy->already_configured)
> +		cdns_phy->already_configured = 0;
> +	else
> +		clk_disable_unprepare(cdns_phy->clk);
> +
> +	return 0;
> +}
> +
> +static int cdns_torrent_phy_resume_noirq(struct device *dev)
> +{
> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
> +	int node = cdns_phy->nsubnodes;
> +	int ret, i;

Ditto.

> +	ret = cdns_torrent_clk(cdns_phy);
> +	if (ret)
> +		goto clk_cleanup;
> +
> +	/* Enable APB */
> +	reset_control_deassert(cdns_phy->apb_rst);
> +
> +	if (cdns_phy->nsubnodes > 1) {
> +		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
> +		if (ret)
> +			goto put_lnk_rst;
> +	}
> +
> +	return 0;
> +
> +put_lnk_rst:
> +	for (i = 0; i < node; i++)
> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> +	reset_control_assert(cdns_phy->apb_rst);
> +	clk_disable_unprepare(cdns_phy->clk);
> +clk_cleanup:
> +	cdns_torrent_clk_cleanup(cdns_phy);
> +	return ret;
> +}

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume support

Posted by Thomas Richard 1 year, 11 months ago

On 2/15/24 16:46, Andy Shevchenko wrote:
>> +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
>> +{
>> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
>> +	int i;
> 
> Why signed?

In the for loop below, the i variable is compared to
cdns_phy->nsubnodes, which is an int.

https://elixir.bootlin.com/linux/latest/source/drivers/phy/cadence/phy-cadence-torrent.c#L360

> 
>> +	reset_control_assert(cdns_phy->phy_rst);
>> +	reset_control_assert(cdns_phy->apb_rst);
>> +	for (i = 0; i < cdns_phy->nsubnodes; i++)
>> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
>> +
>> +	if (cdns_phy->already_configured)
>> +		cdns_phy->already_configured = 0;
>> +	else
>> +		clk_disable_unprepare(cdns_phy->clk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int cdns_torrent_phy_resume_noirq(struct device *dev)
>> +{
>> +	struct cdns_torrent_phy *cdns_phy = dev_get_drvdata(dev);
>> +	int node = cdns_phy->nsubnodes;
>> +	int ret, i;
> 
> Ditto>

Same reason

>> +	ret = cdns_torrent_clk(cdns_phy);
>> +	if (ret)
>> +		goto clk_cleanup;
>> +
>> +	/* Enable APB */
>> +	reset_control_deassert(cdns_phy->apb_rst);
>> +
>> +	if (cdns_phy->nsubnodes > 1) {
>> +		ret = cdns_torrent_phy_configure_multilink(cdns_phy);
>> +		if (ret)
>> +			goto put_lnk_rst;
>> +	}
>> +
>> +	return 0;
>> +
>> +put_lnk_rst:
>> +	for (i = 0; i < node; i++)
>> +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
>> +	reset_control_assert(cdns_phy->apb_rst);
>> +	clk_disable_unprepare(cdns_phy->clk);
>> +clk_cleanup:
>> +	cdns_torrent_clk_cleanup(cdns_phy);
>> +	return ret;
>> +}
> 
-- 
Thomas Richard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com