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* [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management
@ 2020-08-18 15:46 Adam Ford
  2020-08-18 15:46 ` [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL Adam Ford
  2020-08-19  4:59 ` [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Tony Lindgren
  0 siblings, 2 replies; 9+ messages in thread
From: Adam Ford @ 2020-08-18 15:46 UTC (permalink / raw)
  To: linux-omap
  Cc: aford, Adam Ford, Tony Lindgren, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria,
	linux-arm-kernel, linux-kernel, linux-pm

The bandgap sensor can be idled when the processor is too, but it
isn't currently being done, so the power consumption of OMAP3
boards can elevated if the bangap sensor is enabled.

This patch attempts to use some additional power management
to idle the clock to the bandgap when not needed.

Signed-off-by: Adam Ford <aford173@gmail.com>

diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
index ab19ceff6e2a..923ef3abb867 100644
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.c
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
@@ -25,10 +25,18 @@
 #include <linux/of_platform.h>
 #include <linux/of_irq.h>
 #include <linux/io.h>
+#include <linux/cpu_pm.h>
+#include <linux/device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include "ti-bandgap.h"
 
 static int ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id);
+static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
+				  unsigned long cmd, void *v);
 
 /***   Helper functions to access registers and their bitfields   ***/
 
@@ -1008,6 +1016,9 @@ int ti_bandgap_probe(struct platform_device *pdev)
 		}
 	}
 
+	bgp->nb.notifier_call = bandgap_omap_cpu_notifier;
+	cpu_pm_register_notifier(&bgp->nb);
+
 	return 0;
 
 remove_last_cooling:
@@ -1041,7 +1052,9 @@ int ti_bandgap_remove(struct platform_device *pdev)
 	struct ti_bandgap *bgp = platform_get_drvdata(pdev);
 	int i;
 
-	/* First thing is to remove sensor interfaces */
+	cpu_pm_unregister_notifier(&bgp->nb);
+
+	/* Remove sensor interfaces */
 	for (i = 0; i < bgp->conf->sensor_count; i++) {
 		if (bgp->conf->sensors[i].unregister_cooling)
 			bgp->conf->sensors[i].unregister_cooling(bgp, i);
@@ -1153,6 +1166,38 @@ static int ti_bandgap_suspend(struct device *dev)
 	return err;
 }
 
+static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
+				  unsigned long cmd, void *v)
+{
+	struct ti_bandgap *bgp;
+
+	bgp = container_of(nb, struct ti_bandgap, nb);
+
+	spin_lock(&bgp->lock);
+	switch (cmd) {
+	case CPU_CLUSTER_PM_ENTER:
+		if (bgp->is_suspended)
+			break;
+		ti_bandgap_save_ctxt(bgp);
+		ti_bandgap_power(bgp, false);
+		if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+			clk_disable(bgp->fclock);
+		break;
+	case CPU_CLUSTER_PM_ENTER_FAILED:
+	case CPU_CLUSTER_PM_EXIT:
+		if (bgp->is_suspended)
+			break;
+		if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+			clk_enable(bgp->fclock);
+		ti_bandgap_power(bgp, true);
+		ti_bandgap_restore_ctxt(bgp);
+		break;
+	}
+	spin_unlock(&bgp->lock);
+
+	return NOTIFY_OK;
+}
+
 static int ti_bandgap_resume(struct device *dev)
 {
 	struct ti_bandgap *bgp = dev_get_drvdata(dev);
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.h b/drivers/thermal/ti-soc-thermal/ti-bandgap.h
index fce4657e9486..ed0ea4b17b25 100644
--- a/drivers/thermal/ti-soc-thermal/ti-bandgap.h
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.h
@@ -12,6 +12,10 @@
 #include <linux/spinlock.h>
 #include <linux/types.h>
 #include <linux/err.h>
+#include <linux/cpu_pm.h>
+#include <linux/device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm.h>
 
 struct gpio_desc;
 
@@ -203,6 +207,8 @@ struct ti_bandgap {
 	int				irq;
 	struct gpio_desc		*tshut_gpiod;
 	u32				clk_rate;
+	struct notifier_block		nb;
+	unsigned int is_suspended:1;
 };
 
 /**
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL
  2020-08-18 15:46 [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Adam Ford
@ 2020-08-18 15:46 ` Adam Ford
  2020-08-19  4:59 ` [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Tony Lindgren
  1 sibling, 0 replies; 9+ messages in thread
From: Adam Ford @ 2020-08-18 15:46 UTC (permalink / raw)
  To: linux-omap
  Cc: aford, Adam Ford, Tony Lindgren, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria,
	linux-arm-kernel, linux-kernel, linux-pm

With the additional power management options enabled,
this patch enables OMAP3_THERMAL by default.

Signed-off-by: Adam Ford <aford173@gmail.com>

diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
index fe383f5a92fb..efcc46305a47 100644
--- a/arch/arm/configs/omap2plus_defconfig
+++ b/arch/arm/configs/omap2plus_defconfig
@@ -303,6 +303,7 @@ CONFIG_THERMAL_GOV_FAIR_SHARE=y
 CONFIG_THERMAL_GOV_USER_SPACE=y
 CONFIG_CPU_THERMAL=y
 CONFIG_TI_THERMAL=y
+CONFIG_OMAP3_THERMAL=y
 CONFIG_OMAP4_THERMAL=y
 CONFIG_OMAP5_THERMAL=y
 CONFIG_DRA752_THERMAL=y
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management
  2020-08-18 15:46 [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Adam Ford
  2020-08-18 15:46 ` [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL Adam Ford
@ 2020-08-19  4:59 ` Tony Lindgren
  2020-08-19 12:21   ` Adam Ford
  1 sibling, 1 reply; 9+ messages in thread
From: Tony Lindgren @ 2020-08-19  4:59 UTC (permalink / raw)
  To: Adam Ford
  Cc: linux-omap, aford, Russell King, Eduardo Valentin, Keerthy,
	Zhang Rui, Daniel Lezcano, Amit Kucheria, linux-arm-kernel,
	linux-kernel, linux-pm

* Adam Ford <aford173@gmail.com> [200818 15:46]:
> @@ -1153,6 +1166,38 @@ static int ti_bandgap_suspend(struct device *dev)
>  	return err;
>  }
>  
> +static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
> +				  unsigned long cmd, void *v)
> +{
> +	struct ti_bandgap *bgp;
> +
> +	bgp = container_of(nb, struct ti_bandgap, nb);
> +
> +	spin_lock(&bgp->lock);
> +	switch (cmd) {
> +	case CPU_CLUSTER_PM_ENTER:
> +		if (bgp->is_suspended)
> +			break;
> +		ti_bandgap_save_ctxt(bgp);
> +		ti_bandgap_power(bgp, false);
> +		if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> +			clk_disable(bgp->fclock);
> +		break;
> +	case CPU_CLUSTER_PM_ENTER_FAILED:
> +	case CPU_CLUSTER_PM_EXIT:
> +		if (bgp->is_suspended)
> +			break;
> +		if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> +			clk_enable(bgp->fclock);
> +		ti_bandgap_power(bgp, true);
> +		ti_bandgap_restore_ctxt(bgp);
> +		break;
> +	}
> +	spin_unlock(&bgp->lock);
> +
> +	return NOTIFY_OK;
> +}

Hmm to me it looks like is_suspended is not used right now?
I guess you want to set it in ti_bandgap_suspend() and clear
it in ti_bandgap_resume()?

Otherwise looks good to me, I can't test the power consumption
right now though so you may want to check it to make sure
device still hits off mode during idle.

Regards,

Tony

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management
  2020-08-19  4:59 ` [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Tony Lindgren
@ 2020-08-19 12:21   ` Adam Ford
  2020-08-19 12:54     ` Tony Lindgren
  0 siblings, 1 reply; 9+ messages in thread
From: Adam Ford @ 2020-08-19 12:21 UTC (permalink / raw)
  To: Tony Lindgren
  Cc: Linux-OMAP, Adam Ford-BE, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria, arm-soc,
	Linux Kernel Mailing List, linux-pm

On Tue, Aug 18, 2020 at 11:58 PM Tony Lindgren <tony@atomide.com> wrote:
>
> * Adam Ford <aford173@gmail.com> [200818 15:46]:
> > @@ -1153,6 +1166,38 @@ static int ti_bandgap_suspend(struct device *dev)
> >       return err;
> >  }
> >
> > +static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
> > +                               unsigned long cmd, void *v)
> > +{
> > +     struct ti_bandgap *bgp;
> > +
> > +     bgp = container_of(nb, struct ti_bandgap, nb);
> > +
> > +     spin_lock(&bgp->lock);
> > +     switch (cmd) {
> > +     case CPU_CLUSTER_PM_ENTER:
> > +             if (bgp->is_suspended)
> > +                     break;
> > +             ti_bandgap_save_ctxt(bgp);
> > +             ti_bandgap_power(bgp, false);
> > +             if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> > +                     clk_disable(bgp->fclock);
> > +             break;
> > +     case CPU_CLUSTER_PM_ENTER_FAILED:
> > +     case CPU_CLUSTER_PM_EXIT:
> > +             if (bgp->is_suspended)
> > +                     break;
> > +             if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> > +                     clk_enable(bgp->fclock);
> > +             ti_bandgap_power(bgp, true);
> > +             ti_bandgap_restore_ctxt(bgp);
> > +             break;
> > +     }
> > +     spin_unlock(&bgp->lock);
> > +
> > +     return NOTIFY_OK;
> > +}
>
> Hmm to me it looks like is_suspended is not used right now?
> I guess you want to set it in ti_bandgap_suspend() and clear
> it in ti_bandgap_resume()?
>
> Otherwise looks good to me, I can't test the power consumption
> right now though so you may want to check it to make sure
> device still hits off mode during idle.

I have a V2.  Do you want me to re-post 2/2 with V2 as no change, or
should I just submit this patch alone?

adam
>
> Regards,
>
> Tony

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management
  2020-08-19 12:21   ` Adam Ford
@ 2020-08-19 12:54     ` Tony Lindgren
  0 siblings, 0 replies; 9+ messages in thread
From: Tony Lindgren @ 2020-08-19 12:54 UTC (permalink / raw)
  To: Adam Ford
  Cc: Linux-OMAP, Adam Ford-BE, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria, arm-soc,
	Linux Kernel Mailing List, linux-pm

* Adam Ford <aford173@gmail.com> [200819 12:21]:
> On Tue, Aug 18, 2020 at 11:58 PM Tony Lindgren <tony@atomide.com> wrote:
> >
> > * Adam Ford <aford173@gmail.com> [200818 15:46]:
> > > @@ -1153,6 +1166,38 @@ static int ti_bandgap_suspend(struct device *dev)
> > >       return err;
> > >  }
> > >
> > > +static int bandgap_omap_cpu_notifier(struct notifier_block *nb,
> > > +                               unsigned long cmd, void *v)
> > > +{
> > > +     struct ti_bandgap *bgp;
> > > +
> > > +     bgp = container_of(nb, struct ti_bandgap, nb);
> > > +
> > > +     spin_lock(&bgp->lock);
> > > +     switch (cmd) {
> > > +     case CPU_CLUSTER_PM_ENTER:
> > > +             if (bgp->is_suspended)
> > > +                     break;
> > > +             ti_bandgap_save_ctxt(bgp);
> > > +             ti_bandgap_power(bgp, false);
> > > +             if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> > > +                     clk_disable(bgp->fclock);
> > > +             break;
> > > +     case CPU_CLUSTER_PM_ENTER_FAILED:
> > > +     case CPU_CLUSTER_PM_EXIT:
> > > +             if (bgp->is_suspended)
> > > +                     break;
> > > +             if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
> > > +                     clk_enable(bgp->fclock);
> > > +             ti_bandgap_power(bgp, true);
> > > +             ti_bandgap_restore_ctxt(bgp);
> > > +             break;
> > > +     }
> > > +     spin_unlock(&bgp->lock);
> > > +
> > > +     return NOTIFY_OK;
> > > +}
> >
> > Hmm to me it looks like is_suspended is not used right now?
> > I guess you want to set it in ti_bandgap_suspend() and clear
> > it in ti_bandgap_resume()?
> >
> > Otherwise looks good to me, I can't test the power consumption
> > right now though so you may want to check it to make sure
> > device still hits off mode during idle.
> 
> I have a V2.  Do you want me to re-post 2/2 with V2 as no change, or
> should I just submit this patch alone?

Up to you, might make it easier for other folks to follow if the
whole series is reposted.

Regards,

Tony

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL
  2020-10-16 15:19   ` Adam Ford
  2020-11-12 11:34     ` Adam Ford
@ 2020-11-16  8:57     ` Tony Lindgren
  1 sibling, 0 replies; 9+ messages in thread
From: Tony Lindgren @ 2020-11-16  8:57 UTC (permalink / raw)
  To: Adam Ford
  Cc: linux-pm, Linux-OMAP, Adam Ford-BE, Russell King,
	Eduardo Valentin, Keerthy, Zhang Rui, Daniel Lezcano,
	Amit Kucheria, arm-soc, Linux Kernel Mailing List

* Adam Ford <aford173@gmail.com> [201016 15:19]:
> On Fri, Sep 11, 2020 at 7:32 AM Adam Ford <aford173@gmail.com> wrote:
> >
> > With the additional power management options enabled,
> > this patch enables OMAP3_THERMAL by default.
> >
> > Signed-off-by: Adam Ford <aford173@gmail.com>
> > ---
> > V3:  No change
> > V2:  No change
> 
> Tony,
> 
> Can you apply [2/2] to the OMAP branch?

Sorry for the delay, applying into omap-for-v5.11/defconfig thanks.

Regards,

Tony

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL
  2020-10-16 15:19   ` Adam Ford
@ 2020-11-12 11:34     ` Adam Ford
  2020-11-16  8:57     ` Tony Lindgren
  1 sibling, 0 replies; 9+ messages in thread
From: Adam Ford @ 2020-11-12 11:34 UTC (permalink / raw)
  To: linux-pm, Linux-OMAP
  Cc: Adam Ford-BE, Tony Lindgren, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria, arm-soc,
	Linux Kernel Mailing List

On Fri, Oct 16, 2020 at 11:19 AM Adam Ford <aford173@gmail.com> wrote:
>
> On Fri, Sep 11, 2020 at 7:32 AM Adam Ford <aford173@gmail.com> wrote:
> >
> > With the additional power management options enabled,
> > this patch enables OMAP3_THERMAL by default.
> >
> > Signed-off-by: Adam Ford <aford173@gmail.com>
> > ---
> > V3:  No change
> > V2:  No change
>
> Tony,
>
> Can you apply [2/2] to the OMAP branch?
>
> It looks like 1/2 was applied to the linux-pm [1]

Tony,

The defconfig update doesn't show in your branch.  Is there someone
else I should ping about this?

thanks

>
> thanks,
>
> adam
> [1] - https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git/commit/?h=thermal/linux-next&id=5093402e5b449b64f7bbaa09057ce40a8f3c1484
>
>
>
> >
> > diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
> > index fe383f5a92fb..efcc46305a47 100644
> > --- a/arch/arm/configs/omap2plus_defconfig
> > +++ b/arch/arm/configs/omap2plus_defconfig
> > @@ -303,6 +303,7 @@ CONFIG_THERMAL_GOV_FAIR_SHARE=y
> >  CONFIG_THERMAL_GOV_USER_SPACE=y
> >  CONFIG_CPU_THERMAL=y
> >  CONFIG_TI_THERMAL=y
> > +CONFIG_OMAP3_THERMAL=y
> >  CONFIG_OMAP4_THERMAL=y
> >  CONFIG_OMAP5_THERMAL=y
> >  CONFIG_DRA752_THERMAL=y
> > --
> > 2.25.1
> >

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL
  2020-09-11 12:31 ` [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL Adam Ford
@ 2020-10-16 15:19   ` Adam Ford
  2020-11-12 11:34     ` Adam Ford
  2020-11-16  8:57     ` Tony Lindgren
  0 siblings, 2 replies; 9+ messages in thread
From: Adam Ford @ 2020-10-16 15:19 UTC (permalink / raw)
  To: linux-pm, Linux-OMAP
  Cc: Adam Ford-BE, Tony Lindgren, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria, arm-soc,
	Linux Kernel Mailing List

On Fri, Sep 11, 2020 at 7:32 AM Adam Ford <aford173@gmail.com> wrote:
>
> With the additional power management options enabled,
> this patch enables OMAP3_THERMAL by default.
>
> Signed-off-by: Adam Ford <aford173@gmail.com>
> ---
> V3:  No change
> V2:  No change

Tony,

Can you apply [2/2] to the OMAP branch?

It looks like 1/2 was applied to the linux-pm [1]

thanks,

adam
[1] - https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git/commit/?h=thermal/linux-next&id=5093402e5b449b64f7bbaa09057ce40a8f3c1484



>
> diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
> index fe383f5a92fb..efcc46305a47 100644
> --- a/arch/arm/configs/omap2plus_defconfig
> +++ b/arch/arm/configs/omap2plus_defconfig
> @@ -303,6 +303,7 @@ CONFIG_THERMAL_GOV_FAIR_SHARE=y
>  CONFIG_THERMAL_GOV_USER_SPACE=y
>  CONFIG_CPU_THERMAL=y
>  CONFIG_TI_THERMAL=y
> +CONFIG_OMAP3_THERMAL=y
>  CONFIG_OMAP4_THERMAL=y
>  CONFIG_OMAP5_THERMAL=y
>  CONFIG_DRA752_THERMAL=y
> --
> 2.25.1
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL
  2020-09-11 12:31 Adam Ford
@ 2020-09-11 12:31 ` Adam Ford
  2020-10-16 15:19   ` Adam Ford
  0 siblings, 1 reply; 9+ messages in thread
From: Adam Ford @ 2020-09-11 12:31 UTC (permalink / raw)
  To: linux-pm, linux-omap
  Cc: aford, Adam Ford, Tony Lindgren, Russell King, Eduardo Valentin,
	Keerthy, Zhang Rui, Daniel Lezcano, Amit Kucheria,
	linux-arm-kernel, linux-kernel

With the additional power management options enabled,
this patch enables OMAP3_THERMAL by default.

Signed-off-by: Adam Ford <aford173@gmail.com>
---
V3:  No change
V2:  No change

diff --git a/arch/arm/configs/omap2plus_defconfig b/arch/arm/configs/omap2plus_defconfig
index fe383f5a92fb..efcc46305a47 100644
--- a/arch/arm/configs/omap2plus_defconfig
+++ b/arch/arm/configs/omap2plus_defconfig
@@ -303,6 +303,7 @@ CONFIG_THERMAL_GOV_FAIR_SHARE=y
 CONFIG_THERMAL_GOV_USER_SPACE=y
 CONFIG_CPU_THERMAL=y
 CONFIG_TI_THERMAL=y
+CONFIG_OMAP3_THERMAL=y
 CONFIG_OMAP4_THERMAL=y
 CONFIG_OMAP5_THERMAL=y
 CONFIG_DRA752_THERMAL=y
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2020-11-16  9:29 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-18 15:46 [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Adam Ford
2020-08-18 15:46 ` [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL Adam Ford
2020-08-19  4:59 ` [PATCH 1/2] thermal: ti-soc-thermal: Enable addition power management Tony Lindgren
2020-08-19 12:21   ` Adam Ford
2020-08-19 12:54     ` Tony Lindgren
2020-09-11 12:31 Adam Ford
2020-09-11 12:31 ` [PATCH 2/2] ARM: omap2plus_defconfig: Enable OMAP3_THERMAL Adam Ford
2020-10-16 15:19   ` Adam Ford
2020-11-12 11:34     ` Adam Ford
2020-11-16  8:57     ` Tony Lindgren

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