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[PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume

Frank Li posted 4 patches 1 year, 5 months ago
There is a newer version of this series
[PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Frank Li 1 year, 5 months ago 
From: Li Jun <jun.li@nxp.com>

The runtime resume will happen before system resume if system wakeup by
device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.

Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/usb/dwc3/core.c | 13 +++++++++++++
 drivers/usb/dwc3/core.h |  1 +
 2 files changed, 14 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 734de2a8bd212..d60917fad8c52 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
 	dwc3_phy_exit(dwc);
 	dwc3_clk_disable(dwc);
 	reset_control_assert(dwc->reset);
+
+	dwc->core_inited = false;
 }
 
 static bool dwc3_core_is_valid(struct dwc3 *dwc)
@@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
 		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
 	}
 
+	dwc->core_inited = true;
+
 	return 0;
 
 err_power_off_phy:
@@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
 
 	switch (dwc->current_dr_role) {
 	case DWC3_GCTL_PRTCAP_DEVICE:
+		/*
+		 * system resume may come after runtime resume
+		 * e.g. rpm suspend -> pm suspend -> wakeup
+		 * -> rpm resume -> system resume, so if already
+		 *  runtime resumed, system resume should skip it.
+		 */
+		if (dwc->core_inited)
+			break;
+
 		ret = dwc3_core_init_for_resume(dwc);
 		if (ret)
 			return ret;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 1e561fd8b86e2..8a4bfd9a25b19 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1195,6 +1195,7 @@ struct dwc3 {
 	struct clk		*utmi_clk;
 	struct clk		*pipe_clk;
 
+	bool			core_inited;
 	struct reset_control	*reset;
 
 	struct usb_phy		*usb2_phy;

-- 
2.34.1
Re: [PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Thinh Nguyen 1 year, 4 months ago 
On Fri, Jul 12, 2024, Frank Li wrote:
> From: Li Jun <jun.li@nxp.com>
> 
> The runtime resume will happen before system resume if system wakeup by
> device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.

What's the consequence of going through the resuming sequence twice?
Will this cause any functional issue?

Thanks,
Thinh

> 
> Reviewed-by: Peter Chen <peter.chen@nxp.com>
> Signed-off-by: Li Jun <jun.li@nxp.com>
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/usb/dwc3/core.c | 13 +++++++++++++
>  drivers/usb/dwc3/core.h |  1 +
>  2 files changed, 14 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 734de2a8bd212..d60917fad8c52 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
>  	dwc3_phy_exit(dwc);
>  	dwc3_clk_disable(dwc);
>  	reset_control_assert(dwc->reset);
> +
> +	dwc->core_inited = false;
>  }
>  
>  static bool dwc3_core_is_valid(struct dwc3 *dwc)
> @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
>  		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
>  	}
>  
> +	dwc->core_inited = true;
> +
>  	return 0;
>  
>  err_power_off_phy:
> @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
>  
>  	switch (dwc->current_dr_role) {
>  	case DWC3_GCTL_PRTCAP_DEVICE:
> +		/*
> +		 * system resume may come after runtime resume
> +		 * e.g. rpm suspend -> pm suspend -> wakeup
> +		 * -> rpm resume -> system resume, so if already
> +		 *  runtime resumed, system resume should skip it.
> +		 */
> +		if (dwc->core_inited)
> +			break;
> +
>  		ret = dwc3_core_init_for_resume(dwc);
>  		if (ret)
>  			return ret;
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 1e561fd8b86e2..8a4bfd9a25b19 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1195,6 +1195,7 @@ struct dwc3 {
>  	struct clk		*utmi_clk;
>  	struct clk		*pipe_clk;
>  
> +	bool			core_inited;
>  	struct reset_control	*reset;
>  
>  	struct usb_phy		*usb2_phy;
> 
> -- 
> 2.34.1
>
Re: [PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Frank Li 1 year, 4 months ago 
On Wed, Aug 07, 2024 at 01:13:52AM +0000, Thinh Nguyen wrote:
> On Fri, Jul 12, 2024, Frank Li wrote:
> > From: Li Jun <jun.li@nxp.com>
> >
> > The runtime resume will happen before system resume if system wakeup by
> > device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.
>
> What's the consequence of going through the resuming sequence twice?
> Will this cause any functional issue?

static int dwc3_core_init_for_resume(struct dwc3 *dwc)
{

	...
        ret = dwc3_clk_enable(dwc);
        if (ret)
                goto assert_reset;

	...
}

clk will be enabled twice, the reference count in clk will be wrong because
clk_disable() only once at suspend.

So clk will be always ON at next suspend.

Frank Li

>
> Thanks,
> Thinh
>
> >
> > Reviewed-by: Peter Chen <peter.chen@nxp.com>
> > Signed-off-by: Li Jun <jun.li@nxp.com>
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > ---
> >  drivers/usb/dwc3/core.c | 13 +++++++++++++
> >  drivers/usb/dwc3/core.h |  1 +
> >  2 files changed, 14 insertions(+)
> >
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > index 734de2a8bd212..d60917fad8c52 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
> >  	dwc3_phy_exit(dwc);
> >  	dwc3_clk_disable(dwc);
> >  	reset_control_assert(dwc->reset);
> > +
> > +	dwc->core_inited = false;
> >  }
> >
> >  static bool dwc3_core_is_valid(struct dwc3 *dwc)
> > @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
> >  		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
> >  	}
> >
> > +	dwc->core_inited = true;
> > +
> >  	return 0;
> >
> >  err_power_off_phy:
> > @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> >
> >  	switch (dwc->current_dr_role) {
> >  	case DWC3_GCTL_PRTCAP_DEVICE:
> > +		/*
> > +		 * system resume may come after runtime resume
> > +		 * e.g. rpm suspend -> pm suspend -> wakeup
> > +		 * -> rpm resume -> system resume, so if already
> > +		 *  runtime resumed, system resume should skip it.
> > +		 */
> > +		if (dwc->core_inited)
> > +			break;
> > +
> >  		ret = dwc3_core_init_for_resume(dwc);
> >  		if (ret)
> >  			return ret;
> > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > index 1e561fd8b86e2..8a4bfd9a25b19 100644
> > --- a/drivers/usb/dwc3/core.h
> > +++ b/drivers/usb/dwc3/core.h
> > @@ -1195,6 +1195,7 @@ struct dwc3 {
> >  	struct clk		*utmi_clk;
> >  	struct clk		*pipe_clk;
> >
> > +	bool			core_inited;
> >  	struct reset_control	*reset;
> >
> >  	struct usb_phy		*usb2_phy;
> >
> > --
> > 2.34.1
> >
Re: [PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Thinh Nguyen 1 year, 4 months ago 
On Fri, Aug 09, 2024, Frank Li wrote:
> On Wed, Aug 07, 2024 at 01:13:52AM +0000, Thinh Nguyen wrote:
> > On Fri, Jul 12, 2024, Frank Li wrote:
> > > From: Li Jun <jun.li@nxp.com>
> > >
> > > The runtime resume will happen before system resume if system wakeup by
> > > device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.
> >
> > What's the consequence of going through the resuming sequence twice?
> > Will this cause any functional issue?
> 
> static int dwc3_core_init_for_resume(struct dwc3 *dwc)
> {
> 
> 	...
>         ret = dwc3_clk_enable(dwc);
>         if (ret)
>                 goto assert_reset;
> 
> 	...
> }
> 
> clk will be enabled twice, the reference count in clk will be wrong because
> clk_disable() only once at suspend.

Please capture these info in the commit message.

> 
> So clk will be always ON at next suspend.
> 
> Frank Li
> 

dwc3_clk_enable() happens in probe() and dwc3_core_init_for_resume(),
but you're checking dwc->core_inited in dwc3_core_init(). Why?

If the issue is only related to clk_enable(), perhaps just check that?

(minor nit: rename core_inited to core_initialized if you plan to do
that)

Thanks,
Thinh

> > >
> > > Reviewed-by: Peter Chen <peter.chen@nxp.com>
> > > Signed-off-by: Li Jun <jun.li@nxp.com>
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > >  drivers/usb/dwc3/core.c | 13 +++++++++++++
> > >  drivers/usb/dwc3/core.h |  1 +
> > >  2 files changed, 14 insertions(+)
> > >
> > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > index 734de2a8bd212..d60917fad8c52 100644
> > > --- a/drivers/usb/dwc3/core.c
> > > +++ b/drivers/usb/dwc3/core.c
> > > @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
> > >  	dwc3_phy_exit(dwc);
> > >  	dwc3_clk_disable(dwc);
> > >  	reset_control_assert(dwc->reset);
> > > +
> > > +	dwc->core_inited = false;
> > >  }
> > >
> > >  static bool dwc3_core_is_valid(struct dwc3 *dwc)
> > > @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
> > >  		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
> > >  	}
> > >
> > > +	dwc->core_inited = true;
> > > +
> > >  	return 0;
> > >
> > >  err_power_off_phy:
> > > @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> > >
> > >  	switch (dwc->current_dr_role) {
> > >  	case DWC3_GCTL_PRTCAP_DEVICE:
> > > +		/*
> > > +		 * system resume may come after runtime resume
> > > +		 * e.g. rpm suspend -> pm suspend -> wakeup
> > > +		 * -> rpm resume -> system resume, so if already
> > > +		 *  runtime resumed, system resume should skip it.
> > > +		 */
> > > +		if (dwc->core_inited)
> > > +			break;
> > > +
> > >  		ret = dwc3_core_init_for_resume(dwc);
> > >  		if (ret)
> > >  			return ret;
> > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > index 1e561fd8b86e2..8a4bfd9a25b19 100644
> > > --- a/drivers/usb/dwc3/core.h
> > > +++ b/drivers/usb/dwc3/core.h
> > > @@ -1195,6 +1195,7 @@ struct dwc3 {
> > >  	struct clk		*utmi_clk;
> > >  	struct clk		*pipe_clk;
> > >
> > > +	bool			core_inited;
> > >  	struct reset_control	*reset;
> > >
> > >  	struct usb_phy		*usb2_phy;
> > >
> > > --
> > > 2.34.1
> > >
Re: [PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Frank Li 1 year, 4 months ago 
On Fri, Aug 09, 2024 at 11:18:53PM +0000, Thinh Nguyen wrote:
> On Fri, Aug 09, 2024, Frank Li wrote:
> > On Wed, Aug 07, 2024 at 01:13:52AM +0000, Thinh Nguyen wrote:
> > > On Fri, Jul 12, 2024, Frank Li wrote:
> > > > From: Li Jun <jun.li@nxp.com>
> > > >
> > > > The runtime resume will happen before system resume if system wakeup by
> > > > device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.
> > >
> > > What's the consequence of going through the resuming sequence twice?
> > > Will this cause any functional issue?
> >
> > static int dwc3_core_init_for_resume(struct dwc3 *dwc)
> > {
> >
> > 	...
> >         ret = dwc3_clk_enable(dwc);
> >         if (ret)
> >                 goto assert_reset;
> >
> > 	...
> > }
> >
> > clk will be enabled twice, the reference count in clk will be wrong because
> > clk_disable() only once at suspend.
>
> Please capture these info in the commit message.
>
> >
> > So clk will be always ON at next suspend.
> >
> > Frank Li
> >
>
> dwc3_clk_enable() happens in probe() and dwc3_core_init_for_resume(),
> but you're checking dwc->core_inited in dwc3_core_init(). Why?

I have not check dwc->core_inited in dwc3_core_init(). Just set init value
dwc->core_inited = true

Do you means dwc3_core_init() as dwc3_resume_common()?

>
> If the issue is only related to clk_enable(), perhaps just check that?

This should be major one. Any paired operator between suspend/resume should
have issue.

Frank

>
> (minor nit: rename core_inited to core_initialized if you plan to do
> that)
>
> Thanks,
> Thinh
>
> > > >
> > > > Reviewed-by: Peter Chen <peter.chen@nxp.com>
> > > > Signed-off-by: Li Jun <jun.li@nxp.com>
> > > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > > ---
> > > >  drivers/usb/dwc3/core.c | 13 +++++++++++++
> > > >  drivers/usb/dwc3/core.h |  1 +
> > > >  2 files changed, 14 insertions(+)
> > > >
> > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > > index 734de2a8bd212..d60917fad8c52 100644
> > > > --- a/drivers/usb/dwc3/core.c
> > > > +++ b/drivers/usb/dwc3/core.c
> > > > @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
> > > >  	dwc3_phy_exit(dwc);
> > > >  	dwc3_clk_disable(dwc);
> > > >  	reset_control_assert(dwc->reset);
> > > > +
> > > > +	dwc->core_inited = false;
> > > >  }
> > > >
> > > >  static bool dwc3_core_is_valid(struct dwc3 *dwc)
> > > > @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
> > > >  		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
> > > >  	}
> > > >
> > > > +	dwc->core_inited = true;
> > > > +
> > > >  	return 0;
> > > >
> > > >  err_power_off_phy:
> > > > @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> > > >
> > > >  	switch (dwc->current_dr_role) {
> > > >  	case DWC3_GCTL_PRTCAP_DEVICE:
> > > > +		/*
> > > > +		 * system resume may come after runtime resume
> > > > +		 * e.g. rpm suspend -> pm suspend -> wakeup
> > > > +		 * -> rpm resume -> system resume, so if already
> > > > +		 *  runtime resumed, system resume should skip it.
> > > > +		 */
> > > > +		if (dwc->core_inited)
> > > > +			break;
> > > > +
> > > >  		ret = dwc3_core_init_for_resume(dwc);
> > > >  		if (ret)
> > > >  			return ret;
> > > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > > index 1e561fd8b86e2..8a4bfd9a25b19 100644
> > > > --- a/drivers/usb/dwc3/core.h
> > > > +++ b/drivers/usb/dwc3/core.h
> > > > @@ -1195,6 +1195,7 @@ struct dwc3 {
> > > >  	struct clk		*utmi_clk;
> > > >  	struct clk		*pipe_clk;
> > > >
> > > > +	bool			core_inited;
> > > >  	struct reset_control	*reset;
> > > >
> > > >  	struct usb_phy		*usb2_phy;
> > > >
> > > > --
> > > > 2.34.1
> > > >
Re: [PATCH 3/4] usb: dwc3: core: add a core init flag for device mode resume
Posted by Thinh Nguyen 1 year, 4 months ago 
On Tue, Aug 13, 2024, Frank Li wrote:
> On Fri, Aug 09, 2024 at 11:18:53PM +0000, Thinh Nguyen wrote:
> > On Fri, Aug 09, 2024, Frank Li wrote:
> > > On Wed, Aug 07, 2024 at 01:13:52AM +0000, Thinh Nguyen wrote:
> > > > On Fri, Jul 12, 2024, Frank Li wrote:
> > > > > From: Li Jun <jun.li@nxp.com>
> > > > >
> > > > > The runtime resume will happen before system resume if system wakeup by
> > > > > device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.
> > > >
> > > > What's the consequence of going through the resuming sequence twice?
> > > > Will this cause any functional issue?
> > >
> > > static int dwc3_core_init_for_resume(struct dwc3 *dwc)
> > > {
> > >
> > > 	...
> > >         ret = dwc3_clk_enable(dwc);
> > >         if (ret)
> > >                 goto assert_reset;
> > >
> > > 	...
> > > }
> > >
> > > clk will be enabled twice, the reference count in clk will be wrong because
> > > clk_disable() only once at suspend.
> >
> > Please capture these info in the commit message.
> >
> > >
> > > So clk will be always ON at next suspend.
> > >
> > > Frank Li
> > >
> >
> > dwc3_clk_enable() happens in probe() and dwc3_core_init_for_resume(),
> > but you're checking dwc->core_inited in dwc3_core_init(). Why?
> 
> I have not check dwc->core_inited in dwc3_core_init(). Just set init value
> dwc->core_inited = true
> 
> Do you means dwc3_core_init() as dwc3_resume_common()?
> 

You set the dwc->core_inited in dwc3_core_init(). However, you use this
flag to also check if dwc3_clk_enable() is done. dwc3_clk_enable() is
not done in dwc3_core_init().

> >
> > If the issue is only related to clk_enable(), perhaps just check that?
> 
> This should be major one. Any paired operator between suspend/resume should
> have issue.
> 

I don't know what else could be a problem in dwc3_core_init(). As far as
I know, it's only dwc3_clk_enable().

I questioned because of the mismatch use of the check, where the issue
you mentioned is outside of dwc3_core_init(). Perhaps the flag should
not be set there. If that's the case, rename the flag to match the check
condition (if necessary).

> 
> >
> > (minor nit: rename core_inited to core_initialized if you plan to do
> > that)
> >
> > Thanks,
> > Thinh
> >
> > > > >
> > > > > Reviewed-by: Peter Chen <peter.chen@nxp.com>
> > > > > Signed-off-by: Li Jun <jun.li@nxp.com>
> > > > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > > > ---
> > > > >  drivers/usb/dwc3/core.c | 13 +++++++++++++
> > > > >  drivers/usb/dwc3/core.h |  1 +
> > > > >  2 files changed, 14 insertions(+)
> > > > >
> > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > > > index 734de2a8bd212..d60917fad8c52 100644
> > > > > --- a/drivers/usb/dwc3/core.c
> > > > > +++ b/drivers/usb/dwc3/core.c
> > > > > @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
> > > > >  	dwc3_phy_exit(dwc);
> > > > >  	dwc3_clk_disable(dwc);
> > > > >  	reset_control_assert(dwc->reset);
> > > > > +
> > > > > +	dwc->core_inited = false;
> > > > >  }
> > > > >
> > > > >  static bool dwc3_core_is_valid(struct dwc3 *dwc)
> > > > > @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
> > > > >  		dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
> > > > >  	}
> > > > >
> > > > > +	dwc->core_inited = true;
> > > > > +
> > > > >  	return 0;
> > > > >
> > > > >  err_power_off_phy:
> > > > > @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> > > > >
> > > > >  	switch (dwc->current_dr_role) {
> > > > >  	case DWC3_GCTL_PRTCAP_DEVICE:
> > > > > +		/*
> > > > > +		 * system resume may come after runtime resume
> > > > > +		 * e.g. rpm suspend -> pm suspend -> wakeup
> > > > > +		 * -> rpm resume -> system resume, so if already
> > > > > +		 *  runtime resumed, system resume should skip it.
> > > > > +		 */
> > > > > +		if (dwc->core_inited)
> > > > > +			break;
> > > > > +
> > > > >  		ret = dwc3_core_init_for_resume(dwc);
> > > > >  		if (ret)
> > > > >  			return ret;
> > > > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > > > index 1e561fd8b86e2..8a4bfd9a25b19 100644
> > > > > --- a/drivers/usb/dwc3/core.h
> > > > > +++ b/drivers/usb/dwc3/core.h
> > > > > @@ -1195,6 +1195,7 @@ struct dwc3 {
> > > > >  	struct clk		*utmi_clk;
> > > > >  	struct clk		*pipe_clk;
> > > > >
> > > > > +	bool			core_inited;

Document new member of the struct.

> > > > >  	struct reset_control	*reset;
> > > > >
> > > > >  	struct usb_phy		*usb2_phy;
> > > > >
> > > > > --
> > > > > 2.34.1
> > > > >

Thanks,
Thinh

Patchew 2.1-devel-b67e4c2

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