[PATCH net-next 0/2] net: dsa: bcm_sf2: Add support for optional reset controller line

[PATCH net-next 0/2] net: dsa: bcm_sf2: Add support for optional reset controller line

[Florian Fainelli]

Hi David,

This patch series definest the optional reset controller line for the
BCM7445/BCM7278 integrated Ethernet switches and updates the driver to
drive that reset line in lieu of the internal watchdog based reset since
it does not work on BCM7278.

Thanks!

Florian Fainelli (2):
  dt-bindings: net: Describe BCM7445 switch reset property
  net: dsa: bcm_sf2: Add support for optional reset controller line

 .../bindings/net/brcm,bcm7445-switch-v4.0.txt |  6 ++++++
 drivers/net/dsa/bcm_sf2.c                     | 19 +++++++++++++++++++
 drivers/net/dsa/bcm_sf2.h                     |  3 +++
 3 files changed, 28 insertions(+)

-- 
2.17.1

[PATCH net-next 1/2] dt-bindings: net: Describe BCM7445 switch reset property

[Florian Fainelli]

The BCM7445/BCM7278 built-in Ethernet switch have an optional reset line
to the SoC's reset controller, describe the 'resets' and 'reset-names'
properties as optional.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 .../devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt    | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt b/Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt
index b7336b9d6a3c..48a7f916c5e4 100644
--- a/Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt
+++ b/Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt
@@ -44,6 +44,12 @@ Optional properties:
   Admission Control Block supports reporting the number of packets in-flight in a
   switch queue
 
+- resets: a single phandle and reset identifier pair. See
+  Documentation/devicetree/binding/reset/reset.txt for details.
+
+- reset-names: If the "reset" property is specified, this property should have
+  the value "switch" to denote the switch reset line.
+
 Port subnodes:
 
 Optional properties:
-- 
2.17.1

Re: [PATCH net-next 1/2] dt-bindings: net: Describe BCM7445 switch reset property

[Andrew Lunn]

On Mon, Nov 04, 2019 at 10:42:02AM -0800, Florian Fainelli wrote:
> The BCM7445/BCM7278 built-in Ethernet switch have an optional reset line
> to the SoC's reset controller, describe the 'resets' and 'reset-names'
> properties as optional.
> 
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew

[PATCH net-next 2/2] net: dsa: bcm_sf2: Add support for optional reset controller line

[Florian Fainelli]

Grab an optional and exclusive reset controller line for the switch and
manage it during probe/remove functions accordingly. For 7278 devices we
change bcm_sf2_sw_rst() to use the reset controller line since the
WATCHDOG_CTRL register does not reset the switch contrary to stated
documentation.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/dsa/bcm_sf2.c | 19 +++++++++++++++++++
 drivers/net/dsa/bcm_sf2.h |  3 +++
 2 files changed, 22 insertions(+)

diff --git a/drivers/net/dsa/bcm_sf2.c b/drivers/net/dsa/bcm_sf2.c
index 9add84c79dd6..e001c3842afb 100644
--- a/drivers/net/dsa/bcm_sf2.c
+++ b/drivers/net/dsa/bcm_sf2.c
@@ -350,6 +350,18 @@ static int bcm_sf2_sw_rst(struct bcm_sf2_priv *priv)
 {
 	unsigned int timeout = 1000;
 	u32 reg;
+	int ret;
+
+	/* The watchdog reset does not work on 7278, we need to hit the
+	 * "external" reset line through the reset controller.
+	 */
+	if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev)) {
+		ret = reset_control_assert(priv->rcdev);
+		if (ret)
+			return ret;
+
+		return reset_control_deassert(priv->rcdev);
+	}
 
 	reg = core_readl(priv, CORE_WATCHDOG_CTRL);
 	reg |= SOFTWARE_RESET | EN_CHIP_RST | EN_SW_RESET;
@@ -1091,6 +1103,11 @@ static int bcm_sf2_sw_probe(struct platform_device *pdev)
 	priv->core_reg_align = data->core_reg_align;
 	priv->num_cfp_rules = data->num_cfp_rules;
 
+	priv->rcdev = devm_reset_control_get_optional_exclusive(&pdev->dev,
+								"switch");
+	if (PTR_ERR(priv->rcdev) == -EPROBE_DEFER)
+		return PTR_ERR(priv->rcdev);
+
 	/* Auto-detection using standard registers will not work, so
 	 * provide an indication of what kind of device we are for
 	 * b53_common to work with
@@ -1223,6 +1240,8 @@ static int bcm_sf2_sw_remove(struct platform_device *pdev)
 	/* Disable all ports and interrupts */
 	bcm_sf2_sw_suspend(priv->dev->ds);
 	bcm_sf2_mdio_unregister(priv);
+	if (!IS_ERR(priv->rcdev))
+		reset_control_assert(priv->rcdev);
 
 	return 0;
 }
diff --git a/drivers/net/dsa/bcm_sf2.h b/drivers/net/dsa/bcm_sf2.h
index 1df30ccec42d..de386dd96d66 100644
--- a/drivers/net/dsa/bcm_sf2.h
+++ b/drivers/net/dsa/bcm_sf2.h
@@ -18,6 +18,7 @@
 #include <linux/types.h>
 #include <linux/bitops.h>
 #include <linux/if_vlan.h>
+#include <linux/reset.h>
 
 #include <net/dsa.h>
 
@@ -64,6 +65,8 @@ struct bcm_sf2_priv {
 	void __iomem			*fcb;
 	void __iomem			*acb;
 
+	struct reset_control		*rcdev;
+
 	/* Register offsets indirection tables */
 	u32 				type;
 	const u16			*reg_offsets;
-- 
2.17.1

Re: [PATCH net-next 2/2] net: dsa: bcm_sf2: Add support for optional reset controller line

[Andrew Lunn]

> @@ -350,6 +350,18 @@ static int bcm_sf2_sw_rst(struct bcm_sf2_priv *priv)
>  {
>  	unsigned int timeout = 1000;
>  	u32 reg;
> +	int ret;
> +
> +	/* The watchdog reset does not work on 7278, we need to hit the
> +	 * "external" reset line through the reset controller.
> +	 */
> +	if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev)) {
> +		ret = reset_control_assert(priv->rcdev);
> +		if (ret)
> +			return ret;
> +
> +		return reset_control_deassert(priv->rcdev);

Hi Florian

Here you do it conditional on priv->type

> @@ -1223,6 +1240,8 @@ static int bcm_sf2_sw_remove(struct platform_device *pdev)
>  	/* Disable all ports and interrupts */
>  	bcm_sf2_sw_suspend(priv->dev->ds);
>  	bcm_sf2_mdio_unregister(priv);
> +	if (!IS_ERR(priv->rcdev))
> +		reset_control_assert(priv->rcdev);

And here it is unconditional. Seem a bit inconsistent. If it is in DT,
why not use it?

    Andrew

Re: [PATCH net-next 2/2] net: dsa: bcm_sf2: Add support for optional reset controller line

[Florian Fainelli]

On 11/4/19 12:48 PM, Andrew Lunn wrote:
>> @@ -350,6 +350,18 @@ static int bcm_sf2_sw_rst(struct bcm_sf2_priv *priv)
>>  {
>>  	unsigned int timeout = 1000;
>>  	u32 reg;
>> +	int ret;
>> +
>> +	/* The watchdog reset does not work on 7278, we need to hit the
>> +	 * "external" reset line through the reset controller.
>> +	 */
>> +	if (priv->type == BCM7278_DEVICE_ID && !IS_ERR(priv->rcdev)) {
>> +		ret = reset_control_assert(priv->rcdev);
>> +		if (ret)
>> +			return ret;
>> +
>> +		return reset_control_deassert(priv->rcdev);
> 
> Hi Florian
> 
> Here you do it conditional on priv->type
> 
>> @@ -1223,6 +1240,8 @@ static int bcm_sf2_sw_remove(struct platform_device *pdev)
>>  	/* Disable all ports and interrupts */
>>  	bcm_sf2_sw_suspend(priv->dev->ds);
>>  	bcm_sf2_mdio_unregister(priv);
>> +	if (!IS_ERR(priv->rcdev))
>> +		reset_control_assert(priv->rcdev);
> 
> And here it is unconditional. Seem a bit inconsistent. If it is in DT,
> why not use it?

That's an oversight, thanks for spotting that, v2 coming shortly.
-- 
Florian