diff mbox

[v2] can: c_can: Add d_can raminit support

Message ID 1353476650-24398-1-git-send-email-anilkumar@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

AnilKumar, Chimata Nov. 21, 2012, 5:44 a.m. UTC
Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
which holds all the message objects during transmission or
receiving of data. This initialization/de-initialization should
be done in synchronous with D_CAN clock.

In case of AM335X-EVM (current user of D_CAN driver) message RAM is
controlled through control module register for both instances. So
control module register details is required to initialization or
de-initialization of message RAM according to instance number.

Control module memory resource is obtained from D_CAN dt node and
instance number obtained from device tree aliases node.

This patch was tested on AM335x-EVM along with pinctrl data addition
patch, d_can dt aliases addition and control module data addition.
pinctrl data addition is not added to am335x-evm.dts (only supports
CPLD profile#0) because d_can1 is supported under CPLD profile#1.

Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
---
Changes from v1:
	- Incorporated Marc's comments on v1
	  * sanity check moved to c_can_probe() from c_can_hw_raminit()
	  * device instance is assigned using conditional operator
	  * Changed warning to info to tell control module is not
	    used for raminit if there is no second IORESOURCE_MEM
	- Dropped dt patches
	  * No changes from v1
	  * Those will go to linux-omap/master

 drivers/net/can/c_can/c_can.c          |   12 ++++++++++++
 drivers/net/can/c_can/c_can.h          |    3 +++
 drivers/net/can/c_can/c_can_platform.c |   33 +++++++++++++++++++++++++++++++-
 3 files changed, 47 insertions(+), 1 deletion(-)

Comments

Marc Kleine-Budde Nov. 21, 2012, 8:27 a.m. UTC | #1
On 11/21/2012 06:44 AM, AnilKumar Ch wrote:
> Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
> which holds all the message objects during transmission or
> receiving of data. This initialization/de-initialization should
> be done in synchronous with D_CAN clock.
> 
> In case of AM335X-EVM (current user of D_CAN driver) message RAM is
> controlled through control module register for both instances. So
> control module register details is required to initialization or
> de-initialization of message RAM according to instance number.
> 
> Control module memory resource is obtained from D_CAN dt node and
> instance number obtained from device tree aliases node.
> 
> This patch was tested on AM335x-EVM along with pinctrl data addition
> patch, d_can dt aliases addition and control module data addition.
> pinctrl data addition is not added to am335x-evm.dts (only supports
> CPLD profile#0) because d_can1 is supported under CPLD profile#1.
> 
> Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
> ---
> Changes from v1:
> 	- Incorporated Marc's comments on v1
> 	  * sanity check moved to c_can_probe() from c_can_hw_raminit()
> 	  * device instance is assigned using conditional operator
> 	  * Changed warning to info to tell control module is not
> 	    used for raminit if there is no second IORESOURCE_MEM
> 	- Dropped dt patches
> 	  * No changes from v1
> 	  * Those will go to linux-omap/master
> 
>  drivers/net/can/c_can/c_can.c          |   12 ++++++++++++
>  drivers/net/can/c_can/c_can.h          |    3 +++
>  drivers/net/can/c_can/c_can_platform.c |   33 +++++++++++++++++++++++++++++++-
>  3 files changed, 47 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
> index e5180df..c15830c 100644
> --- a/drivers/net/can/c_can/c_can.c
> +++ b/drivers/net/can/c_can/c_can.c
> @@ -233,6 +233,12 @@ static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv)
>  		pm_runtime_put_sync(priv->device);
>  }
>  
> +static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable)
> +{
> +	if (priv->ram_init)
> +		priv->ram_init(priv, enable);
> +}
> +
>  static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
>  {
>  	return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
> @@ -1090,6 +1096,7 @@ static int c_can_open(struct net_device *dev)
>  	struct c_can_priv *priv = netdev_priv(dev);
>  
>  	c_can_pm_runtime_get_sync(priv);
> +	c_can_reset_ram(priv, true);
>  
>  	/* open the can device */
>  	err = open_candev(dev);
> @@ -1118,6 +1125,7 @@ static int c_can_open(struct net_device *dev)
>  exit_irq_fail:
>  	close_candev(dev);
>  exit_open_fail:
> +	c_can_reset_ram(priv, false);
>  	c_can_pm_runtime_put_sync(priv);
>  	return err;
>  }
> @@ -1131,6 +1139,8 @@ static int c_can_close(struct net_device *dev)
>  	c_can_stop(dev);
>  	free_irq(dev->irq, dev);
>  	close_candev(dev);
> +
> +	c_can_reset_ram(priv, false);
>  	c_can_pm_runtime_put_sync(priv);
>  
>  	return 0;
> @@ -1188,6 +1198,7 @@ int c_can_power_down(struct net_device *dev)
>  
>  	c_can_stop(dev);
>  
> +	c_can_reset_ram(priv, false);
>  	c_can_pm_runtime_put_sync(priv);
>  
>  	return 0;
> @@ -1206,6 +1217,7 @@ int c_can_power_up(struct net_device *dev)
>  	WARN_ON(priv->type != BOSCH_D_CAN);
>  
>  	c_can_pm_runtime_get_sync(priv);
> +	c_can_reset_ram(priv, true);
>  
>  	/* Clear PDR and INIT bits */
>  	val = priv->read_reg(priv, C_CAN_CTRL_EX_REG);
> diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
> index e5ed41d..419de5c 100644
> --- a/drivers/net/can/c_can/c_can.h
> +++ b/drivers/net/can/c_can/c_can.h
> @@ -169,6 +169,9 @@ struct c_can_priv {
>  	void *priv;		/* for board-specific data */
>  	u16 irqstatus;
>  	enum c_can_dev_id type;
> +	u32 __iomem *raminit_ctrlreg;
> +	unsigned int instance;
> +	void (*ram_init) (const struct c_can_priv *priv, bool enable);
>  };
>  
>  struct net_device *alloc_c_can_dev(void);
> diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
> index ee141613..d1c31c8 100644
> --- a/drivers/net/can/c_can/c_can_platform.c
> +++ b/drivers/net/can/c_can/c_can_platform.c
> @@ -38,6 +38,8 @@
>  
>  #include "c_can.h"
>  
> +#define CAN_RAMINIT_START_MASK(i)	(1 << (i))
> +
>  /*
>   * 16-bit c_can registers can be arranged differently in the memory
>   * architecture of different implementations. For example: 16-bit
> @@ -68,6 +70,21 @@ static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
>  	writew(val, priv->base + 2 * priv->regs[index]);
>  }
>  
> +static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
> +{
> +	u32 val;
> +
> +	val = readl(priv->raminit_ctrlreg);
> +	if (enable) {
> +		val &= ~CAN_RAMINIT_START_MASK(priv->instance);

What's the point of clearing the bit first?

> +		val |= CAN_RAMINIT_START_MASK(priv->instance);
> +		writel(val, priv->raminit_ctrlreg);
> +	} else {
> +		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
> +		writel(val, priv->raminit_ctrlreg);
> +	}

This should do the same?

	if (enable)
		val |= CAN_RAMINIT_START_MASK(priv->instance);
	else
		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
	writel(val, priv->raminit_ctrlreg);

I can add the changes while applying the patch.

Marc
AnilKumar, Chimata Nov. 21, 2012, 8:37 a.m. UTC | #2
On Wed, Nov 21, 2012 at 13:57:17, Marc Kleine-Budde wrote:
> On 11/21/2012 06:44 AM, AnilKumar Ch wrote:
> > Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
> > which holds all the message objects during transmission or
> > receiving of data. This initialization/de-initialization should
> > be done in synchronous with D_CAN clock.
> > 
> > In case of AM335X-EVM (current user of D_CAN driver) message RAM is
> > controlled through control module register for both instances. So
> > control module register details is required to initialization or
> > de-initialization of message RAM according to instance number.
> > 
> > Control module memory resource is obtained from D_CAN dt node and
> > instance number obtained from device tree aliases node.
> > 
> > This patch was tested on AM335x-EVM along with pinctrl data addition
> > patch, d_can dt aliases addition and control module data addition.
> > pinctrl data addition is not added to am335x-evm.dts (only supports
> > CPLD profile#0) because d_can1 is supported under CPLD profile#1.
> > 
> > Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
> > ---
> > Changes from v1:
> > 	- Incorporated Marc's comments on v1
> > 	  * sanity check moved to c_can_probe() from c_can_hw_raminit()
> > 	  * device instance is assigned using conditional operator
> > 	  * Changed warning to info to tell control module is not
> > 	    used for raminit if there is no second IORESOURCE_MEM
> > 	- Dropped dt patches
> > 	  * No changes from v1
> > 	  * Those will go to linux-omap/master
> > 
> >  drivers/net/can/c_can/c_can.c          |   12 ++++++++++++
> >  drivers/net/can/c_can/c_can.h          |    3 +++
> >  drivers/net/can/c_can/c_can_platform.c |   33 +++++++++++++++++++++++++++++++-
> >  3 files changed, 47 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
> > index e5180df..c15830c 100644
> > --- a/drivers/net/can/c_can/c_can.c
> > +++ b/drivers/net/can/c_can/c_can.c
> > @@ -233,6 +233,12 @@ static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv)
> >  		pm_runtime_put_sync(priv->device);
> >  }
> >  
> > +static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable)
> > +{
> > +	if (priv->ram_init)
> > +		priv->ram_init(priv, enable);
> > +}
> > +
> >  static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
> >  {
> >  	return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
> > @@ -1090,6 +1096,7 @@ static int c_can_open(struct net_device *dev)
> >  	struct c_can_priv *priv = netdev_priv(dev);
> >  
> >  	c_can_pm_runtime_get_sync(priv);
> > +	c_can_reset_ram(priv, true);
> >  
> >  	/* open the can device */
> >  	err = open_candev(dev);
> > @@ -1118,6 +1125,7 @@ static int c_can_open(struct net_device *dev)
> >  exit_irq_fail:
> >  	close_candev(dev);
> >  exit_open_fail:
> > +	c_can_reset_ram(priv, false);
> >  	c_can_pm_runtime_put_sync(priv);
> >  	return err;
> >  }
> > @@ -1131,6 +1139,8 @@ static int c_can_close(struct net_device *dev)
> >  	c_can_stop(dev);
> >  	free_irq(dev->irq, dev);
> >  	close_candev(dev);
> > +
> > +	c_can_reset_ram(priv, false);
> >  	c_can_pm_runtime_put_sync(priv);
> >  
> >  	return 0;
> > @@ -1188,6 +1198,7 @@ int c_can_power_down(struct net_device *dev)
> >  
> >  	c_can_stop(dev);
> >  
> > +	c_can_reset_ram(priv, false);
> >  	c_can_pm_runtime_put_sync(priv);
> >  
> >  	return 0;
> > @@ -1206,6 +1217,7 @@ int c_can_power_up(struct net_device *dev)
> >  	WARN_ON(priv->type != BOSCH_D_CAN);
> >  
> >  	c_can_pm_runtime_get_sync(priv);
> > +	c_can_reset_ram(priv, true);
> >  
> >  	/* Clear PDR and INIT bits */
> >  	val = priv->read_reg(priv, C_CAN_CTRL_EX_REG);
> > diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
> > index e5ed41d..419de5c 100644
> > --- a/drivers/net/can/c_can/c_can.h
> > +++ b/drivers/net/can/c_can/c_can.h
> > @@ -169,6 +169,9 @@ struct c_can_priv {
> >  	void *priv;		/* for board-specific data */
> >  	u16 irqstatus;
> >  	enum c_can_dev_id type;
> > +	u32 __iomem *raminit_ctrlreg;
> > +	unsigned int instance;
> > +	void (*ram_init) (const struct c_can_priv *priv, bool enable);
> >  };
> >  
> >  struct net_device *alloc_c_can_dev(void);
> > diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
> > index ee141613..d1c31c8 100644
> > --- a/drivers/net/can/c_can/c_can_platform.c
> > +++ b/drivers/net/can/c_can/c_can_platform.c
> > @@ -38,6 +38,8 @@
> >  
> >  #include "c_can.h"
> >  
> > +#define CAN_RAMINIT_START_MASK(i)	(1 << (i))
> > +
> >  /*
> >   * 16-bit c_can registers can be arranged differently in the memory
> >   * architecture of different implementations. For example: 16-bit
> > @@ -68,6 +70,21 @@ static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
> >  	writew(val, priv->base + 2 * priv->regs[index]);
> >  }
> >  
> > +static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
> > +{
> > +	u32 val;
> > +
> > +	val = readl(priv->raminit_ctrlreg);
> > +	if (enable) {
> > +		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
> 
> What's the point of clearing the bit first?
> 
> > +		val |= CAN_RAMINIT_START_MASK(priv->instance);
> > +		writel(val, priv->raminit_ctrlreg);
> > +	} else {
> > +		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
> > +		writel(val, priv->raminit_ctrlreg);
> > +	}
> 
> This should do the same?
> 
> 	if (enable)
> 		val |= CAN_RAMINIT_START_MASK(priv->instance);
> 	else
> 		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
> 	writel(val, priv->raminit_ctrlreg);
> 
> I can add the changes while applying the patch.

Thanks Marc.

Thanks
AnilKumar
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Marc Kleine-Budde Nov. 21, 2012, 8:48 a.m. UTC | #3
On 11/21/2012 06:44 AM, AnilKumar Ch wrote:
> Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
> which holds all the message objects during transmission or
> receiving of data. This initialization/de-initialization should
> be done in synchronous with D_CAN clock.
> 
> In case of AM335X-EVM (current user of D_CAN driver) message RAM is
> controlled through control module register for both instances. So
> control module register details is required to initialization or
> de-initialization of message RAM according to instance number.
> 
> Control module memory resource is obtained from D_CAN dt node and
> instance number obtained from device tree aliases node.
> 
> This patch was tested on AM335x-EVM along with pinctrl data addition
> patch, d_can dt aliases addition and control module data addition.
> pinctrl data addition is not added to am335x-evm.dts (only supports
> CPLD profile#0) because d_can1 is supported under CPLD profile#1.
> 
> Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
> ---

[...]

> @@ -178,6 +195,20 @@ static int __devinit c_can_plat_probe(struct platform_device *pdev)
>  		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
>  		priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
>  		priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
> +
> +		if (pdev->dev.of_node)
> +			priv->instance = pdev->id < 0 ?
> +				of_alias_get_id(pdev->dev.of_node, "d_can") :
> +				pdev->id;

This wouldn't work with non DT kernels, what about:

if (pdev->dev.of_node)
	priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
else
	priv->instance = pdev->id;

Marc
> +
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +		priv->raminit_ctrlreg =
> +				devm_request_and_ioremap(&pdev->dev, res);
> +		if (!priv->raminit_ctrlreg || priv->instance < 0) {
> +			dev_info(&pdev->dev, "control memory is not used for raminit\n");
> +			break;
> +		}
> +		priv->ram_init = c_can_hw_raminit;
>  		break;
>  	default:
>  		ret = -EINVAL;
>
AnilKumar, Chimata Nov. 21, 2012, 8:58 a.m. UTC | #4
On Wed, Nov 21, 2012 at 14:18:56, Marc Kleine-Budde wrote:
> On 11/21/2012 06:44 AM, AnilKumar Ch wrote:
> > Add D_CAN raminit support to C_CAN driver to enable D_CAN RAM,
> > which holds all the message objects during transmission or
> > receiving of data. This initialization/de-initialization should
> > be done in synchronous with D_CAN clock.
> > 
> > In case of AM335X-EVM (current user of D_CAN driver) message RAM is
> > controlled through control module register for both instances. So
> > control module register details is required to initialization or
> > de-initialization of message RAM according to instance number.
> > 
> > Control module memory resource is obtained from D_CAN dt node and
> > instance number obtained from device tree aliases node.
> > 
> > This patch was tested on AM335x-EVM along with pinctrl data addition
> > patch, d_can dt aliases addition and control module data addition.
> > pinctrl data addition is not added to am335x-evm.dts (only supports
> > CPLD profile#0) because d_can1 is supported under CPLD profile#1.
> > 
> > Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
> > ---
> 
> [...]
> 
> > @@ -178,6 +195,20 @@ static int __devinit c_can_plat_probe(struct platform_device *pdev)
> >  		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
> >  		priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
> >  		priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
> > +
> > +		if (pdev->dev.of_node)
> > +			priv->instance = pdev->id < 0 ?
> > +				of_alias_get_id(pdev->dev.of_node, "d_can") :
> > +				pdev->id;
> 
> This wouldn't work with non DT kernels, what about:
> 
> if (pdev->dev.of_node)
> 	priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
> else
> 	priv->instance = pdev->id;
> 

I completely forgot this case, yes this is the correct way of doing it.

Thanks
AnilKumar

> > +
> > +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > +		priv->raminit_ctrlreg =
> > +				devm_request_and_ioremap(&pdev->dev, res);
> > +		if (!priv->raminit_ctrlreg || priv->instance < 0) {
> > +			dev_info(&pdev->dev, "control memory is not used for raminit\n");
> > +			break;
> > +		}
> > +		priv->ram_init = c_can_hw_raminit;
> >  		break;
> >  	default:
> >  		ret = -EINVAL;
> > 
> 
> 
> -- 
> Pengutronix e.K.                  | Marc Kleine-Budde           |
> Industrial Linux Solutions        | Phone: +49-231-2826-924     |
> Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
> Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |
> 
> 

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diff mbox

Patch

diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
index e5180df..c15830c 100644
--- a/drivers/net/can/c_can/c_can.c
+++ b/drivers/net/can/c_can/c_can.c
@@ -233,6 +233,12 @@  static inline void c_can_pm_runtime_put_sync(const struct c_can_priv *priv)
 		pm_runtime_put_sync(priv->device);
 }
 
+static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable)
+{
+	if (priv->ram_init)
+		priv->ram_init(priv, enable);
+}
+
 static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
 {
 	return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
@@ -1090,6 +1096,7 @@  static int c_can_open(struct net_device *dev)
 	struct c_can_priv *priv = netdev_priv(dev);
 
 	c_can_pm_runtime_get_sync(priv);
+	c_can_reset_ram(priv, true);
 
 	/* open the can device */
 	err = open_candev(dev);
@@ -1118,6 +1125,7 @@  static int c_can_open(struct net_device *dev)
 exit_irq_fail:
 	close_candev(dev);
 exit_open_fail:
+	c_can_reset_ram(priv, false);
 	c_can_pm_runtime_put_sync(priv);
 	return err;
 }
@@ -1131,6 +1139,8 @@  static int c_can_close(struct net_device *dev)
 	c_can_stop(dev);
 	free_irq(dev->irq, dev);
 	close_candev(dev);
+
+	c_can_reset_ram(priv, false);
 	c_can_pm_runtime_put_sync(priv);
 
 	return 0;
@@ -1188,6 +1198,7 @@  int c_can_power_down(struct net_device *dev)
 
 	c_can_stop(dev);
 
+	c_can_reset_ram(priv, false);
 	c_can_pm_runtime_put_sync(priv);
 
 	return 0;
@@ -1206,6 +1217,7 @@  int c_can_power_up(struct net_device *dev)
 	WARN_ON(priv->type != BOSCH_D_CAN);
 
 	c_can_pm_runtime_get_sync(priv);
+	c_can_reset_ram(priv, true);
 
 	/* Clear PDR and INIT bits */
 	val = priv->read_reg(priv, C_CAN_CTRL_EX_REG);
diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
index e5ed41d..419de5c 100644
--- a/drivers/net/can/c_can/c_can.h
+++ b/drivers/net/can/c_can/c_can.h
@@ -169,6 +169,9 @@  struct c_can_priv {
 	void *priv;		/* for board-specific data */
 	u16 irqstatus;
 	enum c_can_dev_id type;
+	u32 __iomem *raminit_ctrlreg;
+	unsigned int instance;
+	void (*ram_init) (const struct c_can_priv *priv, bool enable);
 };
 
 struct net_device *alloc_c_can_dev(void);
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index ee141613..d1c31c8 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -38,6 +38,8 @@ 
 
 #include "c_can.h"
 
+#define CAN_RAMINIT_START_MASK(i)	(1 << (i))
+
 /*
  * 16-bit c_can registers can be arranged differently in the memory
  * architecture of different implementations. For example: 16-bit
@@ -68,6 +70,21 @@  static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
 	writew(val, priv->base + 2 * priv->regs[index]);
 }
 
+static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+{
+	u32 val;
+
+	val = readl(priv->raminit_ctrlreg);
+	if (enable) {
+		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
+		val |= CAN_RAMINIT_START_MASK(priv->instance);
+		writel(val, priv->raminit_ctrlreg);
+	} else {
+		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
+		writel(val, priv->raminit_ctrlreg);
+	}
+}
+
 static struct platform_device_id c_can_id_table[] = {
 	[BOSCH_C_CAN_PLATFORM] = {
 		.name = KBUILD_MODNAME,
@@ -99,7 +116,7 @@  static int __devinit c_can_plat_probe(struct platform_device *pdev)
 	const struct of_device_id *match;
 	const struct platform_device_id *id;
 	struct pinctrl *pinctrl;
-	struct resource *mem;
+	struct resource *mem, *res;
 	int irq;
 	struct clk *clk;
 
@@ -178,6 +195,20 @@  static int __devinit c_can_plat_probe(struct platform_device *pdev)
 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 		priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 		priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+
+		if (pdev->dev.of_node)
+			priv->instance = pdev->id < 0 ?
+				of_alias_get_id(pdev->dev.of_node, "d_can") :
+				pdev->id;
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		priv->raminit_ctrlreg =
+				devm_request_and_ioremap(&pdev->dev, res);
+		if (!priv->raminit_ctrlreg || priv->instance < 0) {
+			dev_info(&pdev->dev, "control memory is not used for raminit\n");
+			break;
+		}
+		priv->ram_init = c_can_hw_raminit;
 		break;
 	default:
 		ret = -EINVAL;