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  3. [PATCH v2 0/4] can: fsl,flexcan: add fsl,s32v234-flexcan and imx95 wakeup
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[PATCH v2 4/4] can: flexcan: add wakeup support for imx95

Frank Li posted 4 patches 1 year, 5 months ago
[PATCH v2 4/4] can: flexcan: add wakeup support for imx95
Posted by Frank Li 1 year, 5 months ago 
From: Haibo Chen <haibo.chen@nxp.com>

iMX95 defines a bit in GPR that sets/unsets the IPG_STOP signal to the
FlexCAN module, controlling its entry into STOP mode. Wakeup should work
even if FlexCAN is in STOP mode.

Due to iMX95 architecture design, the A-Core cannot access GPR; only the
system manager (SM) can configure GPR. To support the wakeup feature,
follow these steps:

- For suspend:
  1) During Linux suspend, when CAN suspends, do nothing for GPR and keep
     CAN-related clocks on.
  2) In ATF, check whether CAN needs to support wakeup; if yes, send a
     request to SM through the SCMI protocol.
  3) In SM, configure the GPR and unset IPG_STOP.
  4) A-Core suspends.

- For wakeup and resume:
  1) A-Core wakeup event arrives.
  2) In SM, deassert IPG_STOP.
  3) Linux resumes.

Add a new fsl_imx95_devtype_data and FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI to
reflect this.

Reviewed-by: Han Xu <han.xu@nxp.com>
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/net/can/flexcan/flexcan-core.c | 49 ++++++++++++++++++++++++++++++----
 drivers/net/can/flexcan/flexcan.h      |  2 ++
 2 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
index f6e609c388d55..fe972d5b8fbe0 100644
--- a/drivers/net/can/flexcan/flexcan-core.c
+++ b/drivers/net/can/flexcan/flexcan-core.c
@@ -354,6 +354,14 @@ static struct flexcan_devtype_data fsl_imx93_devtype_data = {
 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
 };
 
+static const struct flexcan_devtype_data fsl_imx95_devtype_data = {
+	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
+		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
+		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI |
+		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
+		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
+		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
+};
 static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
@@ -548,6 +556,13 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
 				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
+	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI) {
+		/* For the SCMI mode, driver do nothing, ATF will send request to
+		 * SM(system manager, M33 core) through SCMI protocol after linux
+		 * suspend. Once SM get this request, it will send IPG_STOP signal
+		 * to Flex_CAN, let CAN in STOP mode.
+		 */
+		return 0;
 	}
 
 	return flexcan_low_power_enter_ack(priv);
@@ -559,7 +574,11 @@ static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
 	u32 reg_mcr;
 	int ret;
 
-	/* remove stop request */
+	/* Remove stop request, for FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
+	 * do nothing here, because ATF already send request to SM before
+	 * linux resume. Once SM get this request, it will deassert the
+	 * IPG_STOP signal to Flex_CAN.
+	 */
 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
 		ret = flexcan_stop_mode_enable_scfw(priv, false);
 		if (ret < 0)
@@ -1987,6 +2006,9 @@ static int flexcan_setup_stop_mode(struct platform_device *pdev)
 		ret = flexcan_setup_stop_mode_scfw(pdev);
 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
 		ret = flexcan_setup_stop_mode_gpr(pdev);
+	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
+		/* ATF will handle all STOP_IPG related work */
+		ret = 0;
 	else
 		/* return 0 directly if doesn't support stop mode feature */
 		return 0;
@@ -2013,6 +2035,7 @@ static const struct of_device_id flexcan_of_match[] = {
 	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
 	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
 	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
+	{ .compatible = "fsl,imx95-flexcan", .data = &fsl_imx95_devtype_data, },
 	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
 	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
 	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
@@ -2311,9 +2334,22 @@ static int __maybe_unused flexcan_noirq_suspend(struct device *device)
 	if (netif_running(dev)) {
 		int err;
 
-		if (device_may_wakeup(device))
+		if (device_may_wakeup(device)) {
 			flexcan_enable_wakeup_irq(priv, true);
 
+			/* For FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI, it need
+			 * ATF to send request to SM through SCMI protocol,
+			 * SM will assert the IPG_STOP signal. But all this
+			 * works need the CAN clocks keep on.
+			 * After the CAN module get the IPG_STOP mode, and
+			 * switch to STOP mode, whether still keep the CAN
+			 * clocks on or gate them off depend on the Hardware
+			 * design.
+			 */
+			if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
+				return 0;
+		}
+
 		err = pm_runtime_force_suspend(device);
 		if (err)
 			return err;
@@ -2330,9 +2366,12 @@ static int __maybe_unused flexcan_noirq_resume(struct device *device)
 	if (netif_running(dev)) {
 		int err;
 
-		err = pm_runtime_force_resume(device);
-		if (err)
-			return err;
+		if (!(device_may_wakeup(device) &&
+		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
+			err = pm_runtime_force_resume(device);
+			if (err)
+				return err;
+		}
 
 		if (device_may_wakeup(device))
 			flexcan_enable_wakeup_irq(priv, false);
diff --git a/drivers/net/can/flexcan/flexcan.h b/drivers/net/can/flexcan/flexcan.h
index 025c3417031f4..4933d8c7439e6 100644
--- a/drivers/net/can/flexcan/flexcan.h
+++ b/drivers/net/can/flexcan/flexcan.h
@@ -68,6 +68,8 @@
 #define FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR BIT(15)
 /* Device supports RX via FIFO */
 #define FLEXCAN_QUIRK_SUPPORT_RX_FIFO BIT(16)
+/* Setup stop mode with ATF SCMI protocol to support wakeup */
+#define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI BIT(17)
 
 struct flexcan_devtype_data {
 	u32 quirks;		/* quirks needed for different IP cores */

-- 
2.34.1
Re: [PATCH v2 4/4] can: flexcan: add wakeup support for imx95
Posted by Marc Kleine-Budde 1 year, 5 months ago 
On 15.07.2024 17:27:23, Frank Li wrote:
> From: Haibo Chen <haibo.chen@nxp.com>
> 
> iMX95 defines a bit in GPR that sets/unsets the IPG_STOP signal to the
> FlexCAN module, controlling its entry into STOP mode. Wakeup should work
> even if FlexCAN is in STOP mode.
> 
> Due to iMX95 architecture design, the A-Core cannot access GPR; only the
> system manager (SM) can configure GPR. To support the wakeup feature,
> follow these steps:
> 
> - For suspend:
>   1) During Linux suspend, when CAN suspends, do nothing for GPR and keep
>      CAN-related clocks on.
>   2) In ATF, check whether CAN needs to support wakeup; if yes, send a
>      request to SM through the SCMI protocol.
>   3) In SM, configure the GPR and unset IPG_STOP.
>   4) A-Core suspends.
> 
> - For wakeup and resume:
>   1) A-Core wakeup event arrives.
>   2) In SM, deassert IPG_STOP.
>   3) Linux resumes.
> 
> Add a new fsl_imx95_devtype_data and FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI to
> reflect this.
> 
> Reviewed-by: Han Xu <han.xu@nxp.com>
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/net/can/flexcan/flexcan-core.c | 49 ++++++++++++++++++++++++++++++----
>  drivers/net/can/flexcan/flexcan.h      |  2 ++
>  2 files changed, 46 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
> index f6e609c388d55..fe972d5b8fbe0 100644
> --- a/drivers/net/can/flexcan/flexcan-core.c
> +++ b/drivers/net/can/flexcan/flexcan-core.c
> @@ -354,6 +354,14 @@ static struct flexcan_devtype_data fsl_imx93_devtype_data = {
>  		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
>  };
>  
> +static const struct flexcan_devtype_data fsl_imx95_devtype_data = {
> +	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
> +		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
> +		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI |
> +		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
> +		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
> +		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,

Please keep the flags sorted by their value.

> +};

Please add a newline here.

>  static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
>  	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
>  		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
> @@ -548,6 +556,13 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
>  	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
>  		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
>  				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
> +	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI) {
> +		/* For the SCMI mode, driver do nothing, ATF will send request to
> +		 * SM(system manager, M33 core) through SCMI protocol after linux
> +		 * suspend. Once SM get this request, it will send IPG_STOP signal
> +		 * to Flex_CAN, let CAN in STOP mode.
> +		 */
> +		return 0;
>  	}
>  
>  	return flexcan_low_power_enter_ack(priv);
> @@ -559,7 +574,11 @@ static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
>  	u32 reg_mcr;
>  	int ret;
>  
> -	/* remove stop request */
> +	/* Remove stop request, for FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
> +	 * do nothing here, because ATF already send request to SM before
> +	 * linux resume. Once SM get this request, it will deassert the
> +	 * IPG_STOP signal to Flex_CAN.
> +	 */
>  	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
>  		ret = flexcan_stop_mode_enable_scfw(priv, false);
>  		if (ret < 0)
> @@ -1987,6 +2006,9 @@ static int flexcan_setup_stop_mode(struct platform_device *pdev)
>  		ret = flexcan_setup_stop_mode_scfw(pdev);
>  	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
>  		ret = flexcan_setup_stop_mode_gpr(pdev);
> +	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
> +		/* ATF will handle all STOP_IPG related work */
> +		ret = 0;
>  	else
>  		/* return 0 directly if doesn't support stop mode feature */
>  		return 0;
> @@ -2013,6 +2035,7 @@ static const struct of_device_id flexcan_of_match[] = {
>  	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
>  	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
>  	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
> +	{ .compatible = "fsl,imx95-flexcan", .data = &fsl_imx95_devtype_data, },
>  	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
>  	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
>  	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
> @@ -2311,9 +2334,22 @@ static int __maybe_unused flexcan_noirq_suspend(struct device *device)
>  	if (netif_running(dev)) {
>  		int err;
>  
> -		if (device_may_wakeup(device))
> +		if (device_may_wakeup(device)) {
>  			flexcan_enable_wakeup_irq(priv, true);
>  
> +			/* For FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI, it need
                                                                      needs
> +			 * ATF to send request to SM through SCMI protocol,
> +			 * SM will assert the IPG_STOP signal. But all this
> +			 * works need the CAN clocks keep on.
> +			 * After the CAN module get the IPG_STOP mode, and
                                                gets
> +			 * switch to STOP mode, whether still keep the CAN
                           switches
> +			 * clocks on or gate them off depend on the Hardware
> +			 * design.
> +			 */
> +			if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
> +				return 0;
> +		}
> +
>  		err = pm_runtime_force_suspend(device);
>  		if (err)
>  			return err;
> @@ -2330,9 +2366,12 @@ static int __maybe_unused flexcan_noirq_resume(struct device *device)
>  	if (netif_running(dev)) {
>  		int err;
>  
> -		err = pm_runtime_force_resume(device);
> -		if (err)
> -			return err;
> +		if (!(device_may_wakeup(device) &&
                      ^^^^^^^^^^^^^^^^^^^^^^^^

Where does this come from?

> +		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
> +			err = pm_runtime_force_resume(device);
> +			if (err)
> +				return err;
> +		}
>  
>  		if (device_may_wakeup(device))
>  			flexcan_enable_wakeup_irq(priv, false);
> diff --git a/drivers/net/can/flexcan/flexcan.h b/drivers/net/can/flexcan/flexcan.h
> index 025c3417031f4..4933d8c7439e6 100644
> --- a/drivers/net/can/flexcan/flexcan.h
> +++ b/drivers/net/can/flexcan/flexcan.h
> @@ -68,6 +68,8 @@
>  #define FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR BIT(15)
>  /* Device supports RX via FIFO */
>  #define FLEXCAN_QUIRK_SUPPORT_RX_FIFO BIT(16)
> +/* Setup stop mode with ATF SCMI protocol to support wakeup */
> +#define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI BIT(17)
>  
>  struct flexcan_devtype_data {
>  	u32 quirks;		/* quirks needed for different IP cores */
> 
> -- 
> 2.34.1
> 
> 

regards,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |
Re: [PATCH v2 4/4] can: flexcan: add wakeup support for imx95
Posted by Frank Li 1 year, 5 months ago 
On Tue, Jul 16, 2024 at 09:06:14AM +0200, Marc Kleine-Budde wrote:
> On 15.07.2024 17:27:23, Frank Li wrote:
> > From: Haibo Chen <haibo.chen@nxp.com>
> > 
> > iMX95 defines a bit in GPR that sets/unsets the IPG_STOP signal to the
> > FlexCAN module, controlling its entry into STOP mode. Wakeup should work
> > even if FlexCAN is in STOP mode.
> > 
> > Due to iMX95 architecture design, the A-Core cannot access GPR; only the
> > system manager (SM) can configure GPR. To support the wakeup feature,
> > follow these steps:
> > 
> > - For suspend:
> >   1) During Linux suspend, when CAN suspends, do nothing for GPR and keep
> >      CAN-related clocks on.
> >   2) In ATF, check whether CAN needs to support wakeup; if yes, send a
> >      request to SM through the SCMI protocol.
> >   3) In SM, configure the GPR and unset IPG_STOP.
> >   4) A-Core suspends.
> > 
> > - For wakeup and resume:
> >   1) A-Core wakeup event arrives.
> >   2) In SM, deassert IPG_STOP.
> >   3) Linux resumes.
> > 
> > Add a new fsl_imx95_devtype_data and FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI to
> > reflect this.
> > 
> > Reviewed-by: Han Xu <han.xu@nxp.com>
> > Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> > Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > ---
> >  drivers/net/can/flexcan/flexcan-core.c | 49 ++++++++++++++++++++++++++++++----
> >  drivers/net/can/flexcan/flexcan.h      |  2 ++
> >  2 files changed, 46 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
> > index f6e609c388d55..fe972d5b8fbe0 100644
> > --- a/drivers/net/can/flexcan/flexcan-core.c
> > +++ b/drivers/net/can/flexcan/flexcan-core.c
> > @@ -354,6 +354,14 @@ static struct flexcan_devtype_data fsl_imx93_devtype_data = {
> >  		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
> >  };
> >  
> > +static const struct flexcan_devtype_data fsl_imx95_devtype_data = {
> > +	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
> > +		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
> > +		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI |
> > +		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
> > +		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
> > +		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
> 
> Please keep the flags sorted by their value.
> 
> > +};
> 
> Please add a newline here.
> 
> >  static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
> >  	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
> >  		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
> > @@ -548,6 +556,13 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
> >  	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
> >  		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
> >  				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
> > +	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI) {
> > +		/* For the SCMI mode, driver do nothing, ATF will send request to
> > +		 * SM(system manager, M33 core) through SCMI protocol after linux
> > +		 * suspend. Once SM get this request, it will send IPG_STOP signal
> > +		 * to Flex_CAN, let CAN in STOP mode.
> > +		 */
> > +		return 0;
> >  	}
> >  
> >  	return flexcan_low_power_enter_ack(priv);
> > @@ -559,7 +574,11 @@ static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
> >  	u32 reg_mcr;
> >  	int ret;
> >  
> > -	/* remove stop request */
> > +	/* Remove stop request, for FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
> > +	 * do nothing here, because ATF already send request to SM before
> > +	 * linux resume. Once SM get this request, it will deassert the
> > +	 * IPG_STOP signal to Flex_CAN.
> > +	 */
> >  	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
> >  		ret = flexcan_stop_mode_enable_scfw(priv, false);
> >  		if (ret < 0)
> > @@ -1987,6 +2006,9 @@ static int flexcan_setup_stop_mode(struct platform_device *pdev)
> >  		ret = flexcan_setup_stop_mode_scfw(pdev);
> >  	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
> >  		ret = flexcan_setup_stop_mode_gpr(pdev);
> > +	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
> > +		/* ATF will handle all STOP_IPG related work */
> > +		ret = 0;
> >  	else
> >  		/* return 0 directly if doesn't support stop mode feature */
> >  		return 0;
> > @@ -2013,6 +2035,7 @@ static const struct of_device_id flexcan_of_match[] = {
> >  	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
> >  	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
> >  	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
> > +	{ .compatible = "fsl,imx95-flexcan", .data = &fsl_imx95_devtype_data, },
> >  	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
> >  	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
> >  	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
> > @@ -2311,9 +2334,22 @@ static int __maybe_unused flexcan_noirq_suspend(struct device *device)
> >  	if (netif_running(dev)) {
> >  		int err;
> >  
> > -		if (device_may_wakeup(device))
> > +		if (device_may_wakeup(device)) {
> >  			flexcan_enable_wakeup_irq(priv, true);
> >  
> > +			/* For FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI, it need
>                                                                       needs
> > +			 * ATF to send request to SM through SCMI protocol,
> > +			 * SM will assert the IPG_STOP signal. But all this
> > +			 * works need the CAN clocks keep on.
> > +			 * After the CAN module get the IPG_STOP mode, and
>                                                 gets
> > +			 * switch to STOP mode, whether still keep the CAN
>                            switches
> > +			 * clocks on or gate them off depend on the Hardware
> > +			 * design.
> > +			 */
> > +			if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
> > +				return 0;
> > +		}
> > +
> >  		err = pm_runtime_force_suspend(device);
> >  		if (err)
> >  			return err;
> > @@ -2330,9 +2366,12 @@ static int __maybe_unused flexcan_noirq_resume(struct device *device)
> >  	if (netif_running(dev)) {
> >  		int err;
> >  
> > -		err = pm_runtime_force_resume(device);
> > -		if (err)
> > -			return err;
> > +		if (!(device_may_wakeup(device) &&
>                       ^^^^^^^^^^^^^^^^^^^^^^^^
> 
> Where does this come from?

include/linux/pm_wakeup.h

static inline bool device_may_wakeup(struct device *dev)                                            
{                                                                                                   
        return dev->power.can_wakeup && !!dev->power.wakeup;                                        
}

Frank

> 
> > +		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
> > +			err = pm_runtime_force_resume(device);
> > +			if (err)
> > +				return err;
> > +		}
> >  
> >  		if (device_may_wakeup(device))
> >  			flexcan_enable_wakeup_irq(priv, false);
> > diff --git a/drivers/net/can/flexcan/flexcan.h b/drivers/net/can/flexcan/flexcan.h
> > index 025c3417031f4..4933d8c7439e6 100644
> > --- a/drivers/net/can/flexcan/flexcan.h
> > +++ b/drivers/net/can/flexcan/flexcan.h
> > @@ -68,6 +68,8 @@
> >  #define FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR BIT(15)
> >  /* Device supports RX via FIFO */
> >  #define FLEXCAN_QUIRK_SUPPORT_RX_FIFO BIT(16)
> > +/* Setup stop mode with ATF SCMI protocol to support wakeup */
> > +#define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI BIT(17)
> >  
> >  struct flexcan_devtype_data {
> >  	u32 quirks;		/* quirks needed for different IP cores */
> > 
> > -- 
> > 2.34.1
> > 
> > 
> 
> regards,
> Marc
> 
> -- 
> Pengutronix e.K.                 | Marc Kleine-Budde          |
> Embedded Linux                   | https://www.pengutronix.de |
> Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
> Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |
Re: [PATCH v2 4/4] can: flexcan: add wakeup support for imx95
Posted by Marc Kleine-Budde 1 year, 5 months ago 
On 16.07.2024 10:40:31, Frank Li wrote:
> > > @@ -2330,9 +2366,12 @@ static int __maybe_unused flexcan_noirq_resume(struct device *device)
> > >  	if (netif_running(dev)) {
> > >  		int err;
> > >  
> > > -		err = pm_runtime_force_resume(device);
> > > -		if (err)
> > > -			return err;
> > > +		if (!(device_may_wakeup(device) &&
> >                       ^^^^^^^^^^^^^^^^^^^^^^^^
> > 
> > Where does this come from?
> 
> include/linux/pm_wakeup.h
> 
> static inline bool device_may_wakeup(struct device *dev)                                            
> {                                                                                                   
>         return dev->power.can_wakeup && !!dev->power.wakeup;                                        
> }

Sorry for the confusion. I wanted to point out, that the original driver
doesn't have the check to device_may_wakeup(). Why was this added?

> > 
> > > +		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
> > > +			err = pm_runtime_force_resume(device);
> > > +			if (err)
> > > +				return err;
> > > +		}
> > >  
> > >  		if (device_may_wakeup(device))
> > >  			flexcan_enable_wakeup_irq(priv, false);
> > > diff --git a/drivers/net/can/flexcan/flexcan.h b/drivers/net/can/flexcan/flexcan.h
> > > index 025c3417031f4..4933d8c7439e6 100644
> > > --- a/drivers/net/can/flexcan/flexcan.h
> > > +++ b/drivers/net/can/flexcan/flexcan.h
> > > @@ -68,6 +68,8 @@
> > >  #define FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR BIT(15)
> > >  /* Device supports RX via FIFO */
> > >  #define FLEXCAN_QUIRK_SUPPORT_RX_FIFO BIT(16)
> > > +/* Setup stop mode with ATF SCMI protocol to support wakeup */
> > > +#define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI BIT(17)
> > >  
> > >  struct flexcan_devtype_data {
> > >  	u32 quirks;		/* quirks needed for different IP cores */

regards,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |

Patchew 2.1-devel-b67e4c2

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