[PATCH net-next 0/3] net: mscc-miim: add integrated PHY reset support

[PATCH net-next 0/3] net: mscc-miim: add integrated PHY reset support

[Michael Walle]

The MDIO driver has support to release the integrated PHYs from reset.
This was implemented for the SparX-5 for now. Now add support for the
LAN966x, too.

Michael Walle (3):
  dt-bindings: net: mscc-miim: add lan966x compatible
  net: mdio: mscc-miim: replace magic numbers for the bus reset
  net: mdio: mscc-miim: add lan966x internal phy reset support

 .../devicetree/bindings/net/mscc-miim.txt     |  2 +-
 drivers/net/mdio/mdio-mscc-miim.c             | 59 +++++++++++++------
 2 files changed, 42 insertions(+), 19 deletions(-)

-- 
2.30.2

[PATCH net-next 1/3] dt-bindings: net: mscc-miim: add lan966x compatible

[Michael Walle]

The MDIO controller has support to release the internal PHYs from reset
by specifying a second memory resource. This is different between the
currently supported SparX-5 and the LAN966x. Add a new compatible to
distiguish between these two.

Signed-off-by: Michael Walle <michael@walle.cc>
---
 Documentation/devicetree/bindings/net/mscc-miim.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/net/mscc-miim.txt b/Documentation/devicetree/bindings/net/mscc-miim.txt
index 7104679cf59d..a9efff252ca6 100644
--- a/Documentation/devicetree/bindings/net/mscc-miim.txt
+++ b/Documentation/devicetree/bindings/net/mscc-miim.txt
@@ -2,7 +2,7 @@ Microsemi MII Management Controller (MIIM) / MDIO
 =================================================
 
 Properties:
-- compatible: must be "mscc,ocelot-miim"
+- compatible: must be "mscc,ocelot-miim" or "mscc,lan966x-miim"
 - reg: The base address of the MDIO bus controller register bank. Optionally, a
   second register bank can be defined if there is an associated reset register
   for internal PHYs
-- 
2.30.2

[PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

[Michael Walle]

Replace the magic numbers by macros which are already defined. It seems
the original commit missed to use them.

Signed-off-by: Michael Walle <michael@walle.cc>
---
 drivers/net/mdio/mdio-mscc-miim.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/mdio/mdio-mscc-miim.c b/drivers/net/mdio/mdio-mscc-miim.c
index 64fb76c1e395..7773d5019e66 100644
--- a/drivers/net/mdio/mdio-mscc-miim.c
+++ b/drivers/net/mdio/mdio-mscc-miim.c
@@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
 {
 	struct mscc_miim_dev *miim = bus->priv;
 	int offset = miim->phy_reset_offset;
+	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
+		   PHY_CFG_PHY_RESET;
 	int ret;
 
 	if (miim->phy_regs) {
-		ret = regmap_write(miim->phy_regs,
-				   MSCC_PHY_REG_PHY_CFG + offset, 0);
+		ret = regmap_write(miim->phy_regs, offset, 0);
 		if (ret < 0) {
 			WARN_ONCE(1, "mscc reset set error %d\n", ret);
 			return ret;
 		}
 
-		ret = regmap_write(miim->phy_regs,
-				   MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
+		ret = regmap_write(miim->phy_regs, offset, mask);
 		if (ret < 0) {
 			WARN_ONCE(1, "mscc reset clear error %d\n", ret);
 			return ret;
@@ -272,7 +272,7 @@ static int mscc_miim_probe(struct platform_device *pdev)
 
 	miim = bus->priv;
 	miim->phy_regs = phy_regmap;
-	miim->phy_reset_offset = 0;
+	miim->phy_reset_offset = MSCC_PHY_REG_PHY_CFG;
 
 	ret = of_mdiobus_register(bus, pdev->dev.of_node);
 	if (ret < 0) {
-- 
2.30.2

[PATCH net-next 3/3] et: mdio: mscc-miim: add lan966x internal phy reset support

[Michael Walle]

The LAN966x has two internal PHYs which are in reset by default. The
driver already supported the internal PHYs of the SparX-5. Now add
support for the LAN966x, too. Add a new compatible to distinguish them.

The LAN966x has additional control bits in this register, thus convert
the regmap_write() to regmap_update_bits() to leave the remaining bits
untouched. This doesn't change anything for the SparX-5 SoC, because
there, the register consists only of reset bits.

Signed-off-by: Michael Walle <michael@walle.cc>
---
 drivers/net/mdio/mdio-mscc-miim.c | 59 +++++++++++++++++++++----------
 1 file changed, 41 insertions(+), 18 deletions(-)

diff --git a/drivers/net/mdio/mdio-mscc-miim.c b/drivers/net/mdio/mdio-mscc-miim.c
index 7773d5019e66..d082a13d9af3 100644
--- a/drivers/net/mdio/mdio-mscc-miim.c
+++ b/drivers/net/mdio/mdio-mscc-miim.c
@@ -15,6 +15,7 @@
 #include <linux/of_mdio.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 
 #define MSCC_MIIM_REG_STATUS		0x0
@@ -36,11 +37,19 @@
 #define		PHY_CFG_PHY_RESET	(BIT(5) | BIT(6) | BIT(7) | BIT(8))
 #define MSCC_PHY_REG_PHY_STATUS	0x4
 
+#define LAN966X_CUPHY_COMMON_CFG	0x0
+#define		CUPHY_COMMON_CFG_RESET_N	BIT(0)
+
+struct mscc_miim_info {
+	unsigned int phy_reset_offset;
+	unsigned int phy_reset_mask;
+};
+
 struct mscc_miim_dev {
 	struct regmap *regs;
 	int mii_status_offset;
 	struct regmap *phy_regs;
-	int phy_reset_offset;
+	const struct mscc_miim_info *info;
 };
 
 /* When high resolution timers aren't built-in: we can't use usleep_range() as
@@ -157,27 +166,29 @@ static int mscc_miim_write(struct mii_bus *bus, int mii_id,
 static int mscc_miim_reset(struct mii_bus *bus)
 {
 	struct mscc_miim_dev *miim = bus->priv;
-	int offset = miim->phy_reset_offset;
-	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
-		   PHY_CFG_PHY_RESET;
+	unsigned int offset, mask;
 	int ret;
 
-	if (miim->phy_regs) {
-		ret = regmap_write(miim->phy_regs, offset, 0);
-		if (ret < 0) {
-			WARN_ONCE(1, "mscc reset set error %d\n", ret);
-			return ret;
-		}
+	if (!miim->phy_regs || !miim->info)
+		return 0;
 
-		ret = regmap_write(miim->phy_regs, offset, mask);
-		if (ret < 0) {
-			WARN_ONCE(1, "mscc reset clear error %d\n", ret);
-			return ret;
-		}
+	offset = miim->info->phy_reset_offset;
+	mask = miim->info->phy_reset_mask;
+
+	ret = regmap_update_bits(miim->phy_regs, offset, mask, 0);
+	if (ret < 0) {
+		WARN_ONCE(1, "mscc reset set error %d\n", ret);
+		return ret;
+	}
 
-		mdelay(500);
+	ret = regmap_update_bits(miim->phy_regs, offset, mask, mask);
+	if (ret < 0) {
+		WARN_ONCE(1, "mscc reset clear error %d\n", ret);
+		return ret;
 	}
 
+	mdelay(500);
+
 	return 0;
 }
 
@@ -272,7 +283,7 @@ static int mscc_miim_probe(struct platform_device *pdev)
 
 	miim = bus->priv;
 	miim->phy_regs = phy_regmap;
-	miim->phy_reset_offset = MSCC_PHY_REG_PHY_CFG;
+	miim->info = device_get_match_data(&pdev->dev);
 
 	ret = of_mdiobus_register(bus, pdev->dev.of_node);
 	if (ret < 0) {
@@ -294,8 +305,20 @@ static int mscc_miim_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct mscc_miim_info mscc_ocelot_miim_info = {
+	.phy_reset_offset = MSCC_PHY_REG_PHY_CFG,
+	.phy_reset_mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
+			  PHY_CFG_PHY_RESET,
+};
+
+static const struct mscc_miim_info mscc_lan966x_miim_info = {
+	.phy_reset_offset = LAN966X_CUPHY_COMMON_CFG,
+	.phy_reset_mask = CUPHY_COMMON_CFG_RESET_N,
+};
+
 static const struct of_device_id mscc_miim_match[] = {
-	{ .compatible = "mscc,ocelot-miim" },
+	{ .compatible = "mscc,ocelot-miim", .data = &mscc_ocelot_miim_info },
+	{ .compatible = "mscc,lan966x-miim", .data = &mscc_lan966x_miim_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, mscc_miim_match);
-- 
2.30.2

Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

[Andrew Lunn]

> diff --git a/drivers/net/mdio/mdio-mscc-miim.c b/drivers/net/mdio/mdio-mscc-miim.c
> index 64fb76c1e395..7773d5019e66 100644
> --- a/drivers/net/mdio/mdio-mscc-miim.c
> +++ b/drivers/net/mdio/mdio-mscc-miim.c
> @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
>  {
>  	struct mscc_miim_dev *miim = bus->priv;
>  	int offset = miim->phy_reset_offset;
> +	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
> +		   PHY_CFG_PHY_RESET;

> -		ret = regmap_write(miim->phy_regs,
> -				   MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
> +		ret = regmap_write(miim->phy_regs, offset, mask);

Is mask the correct name? It is not being used in the typical way for
a mask.

  Andrew

Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

[Michael Walle]

Am 2022-03-13 01:51, schrieb Andrew Lunn:
>> diff --git a/drivers/net/mdio/mdio-mscc-miim.c 
>> b/drivers/net/mdio/mdio-mscc-miim.c
>> index 64fb76c1e395..7773d5019e66 100644
>> --- a/drivers/net/mdio/mdio-mscc-miim.c
>> +++ b/drivers/net/mdio/mdio-mscc-miim.c
>> @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
>>  {
>>  	struct mscc_miim_dev *miim = bus->priv;
>>  	int offset = miim->phy_reset_offset;
>> +	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
>> +		   PHY_CFG_PHY_RESET;
> 
>> -		ret = regmap_write(miim->phy_regs,
>> -				   MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
>> +		ret = regmap_write(miim->phy_regs, offset, mask);
> 
> Is mask the correct name? It is not being used in the typical way for
> a mask.

It is the mask of all the reset bits, see also patch 3/3. Either all
these bits are set or none. Do you have any suggestion? I thought about
adding mask and value for the remap_update_bits() in patch 3/3 but
decided against it, just because it doesn't add any value because
mask and value are the same.

-michael

Re: [PATCH net-next 3/3] et: mdio: mscc-miim: add lan966x internal phy reset support

[Andrew Lunn]

>  /* When high resolution timers aren't built-in: we can't use usleep_range() as
> @@ -157,27 +166,29 @@ static int mscc_miim_write(struct mii_bus *bus, int mii_id,
>  static int mscc_miim_reset(struct mii_bus *bus)
>  {
>  	struct mscc_miim_dev *miim = bus->priv;
> -	int offset = miim->phy_reset_offset;
> -	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
> -		   PHY_CFG_PHY_RESET;
> +	unsigned int offset, mask;
>  	int ret;
>  
> -	if (miim->phy_regs) {
> -		ret = regmap_write(miim->phy_regs, offset, 0);
> -		if (ret < 0) {
> -			WARN_ONCE(1, "mscc reset set error %d\n", ret);
> -			return ret;
> -		}
> +	if (!miim->phy_regs || !miim->info)
> +		return 0;

I would put the check for miim->info in the probe. Not checking the
return value from *_get_match_data() is one of the things the bots
reports and we receive patches for. You have the check, but it is
hidden away, and i doubt the bot nor the bot handlers are clever
enough to find it.

       Andrew

Re: [PATCH net-next 2/3] net: mdio: mscc-miim: replace magic numbers for the bus reset

[Andrew Lunn]

On Sun, Mar 13, 2022 at 02:17:55AM +0100, Michael Walle wrote:
> Am 2022-03-13 01:51, schrieb Andrew Lunn:
> > > diff --git a/drivers/net/mdio/mdio-mscc-miim.c
> > > b/drivers/net/mdio/mdio-mscc-miim.c
> > > index 64fb76c1e395..7773d5019e66 100644
> > > --- a/drivers/net/mdio/mdio-mscc-miim.c
> > > +++ b/drivers/net/mdio/mdio-mscc-miim.c
> > > @@ -158,18 +158,18 @@ static int mscc_miim_reset(struct mii_bus *bus)
> > >  {
> > >  	struct mscc_miim_dev *miim = bus->priv;
> > >  	int offset = miim->phy_reset_offset;
> > > +	int mask = PHY_CFG_PHY_ENA | PHY_CFG_PHY_COMMON_RESET |
> > > +		   PHY_CFG_PHY_RESET;
> > 
> > > -		ret = regmap_write(miim->phy_regs,
> > > -				   MSCC_PHY_REG_PHY_CFG + offset, 0x1ff);
> > > +		ret = regmap_write(miim->phy_regs, offset, mask);
> > 
> > Is mask the correct name? It is not being used in the typical way for
> > a mask.
> 
> It is the mask of all the reset bits, see also patch 3/3. Either all
> these bits are set or none.

Yes, it is you just don't use it in the typical way for a mask

	foo = bar & mask;

The name mask made me look for a read-modify-write or similar. And
that then makes me thing of race conditions.

> Do you haave any suggestion?

value everywhere? Or phy_reset_bits?

      Andrew