diff mbox series

[net-next,v2,1/2] net: dsa: mt7530-mdio: read PHY address of switch from device tree

Message ID 20240414-b4-for-netnext-mt7530-phy-addr-from-dt-and-simplify-core-ops-v2-1-1a7649c4d3b6@arinc9.com (mailing list archive)
State New
Headers show
Series Read PHY address of switch from device tree on MT7530 DSA subdriver | expand

Commit Message

Arınç ÜNAL via B4 Relay April 14, 2024, 6:07 a.m. UTC
From: Arınç ÜNAL <arinc.unal@arinc9.com>

Read the PHY address the switch listens on from the reg property of the
switch node on the device tree. This change brings support for MT7530
switches on boards with such bootstrapping configuration where the switch
listens on a different PHY address than the hardcoded PHY address on the
driver, 31.

As described on the "MT7621 Programming Guide v0.4" document, the MT7530
switch and its PHYs can be configured to listen on the range of 7-12,
15-20, 23-28, and 31 and 0-4 PHY addresses.

There are operations where the switch PHY registers are used. For the PHY
address of the control PHY, transform the MT753X_CTRL_PHY_ADDR constant
into a macro and use it. The PHY address for the control PHY is 0 when the
switch listens on 31. In any other case, it is one greater than the PHY
address the switch listens on.

Reviewed-by: Daniel Golle <daniel@makrotopia.org>
Tested-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
---
 drivers/net/dsa/mt7530-mdio.c | 28 ++++++++++++++--------------
 drivers/net/dsa/mt7530.c      | 35 ++++++++++++++++++++++-------------
 drivers/net/dsa/mt7530.h      |  4 +++-
 3 files changed, 39 insertions(+), 28 deletions(-)

Comments

Arınç ÜNAL April 14, 2024, 8:17 a.m. UTC | #1
On 14.04.2024 09:07, Arınç ÜNAL via B4 Relay wrote:
> From: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Read the PHY address the switch listens on from the reg property of the
> switch node on the device tree. This change brings support for MT7530
> switches on boards with such bootstrapping configuration where the switch
> listens on a different PHY address than the hardcoded PHY address on the
> driver, 31.
> 
> As described on the "MT7621 Programming Guide v0.4" document, the MT7530
> switch and its PHYs can be configured to listen on the range of 7-12,
> 15-20, 23-28, and 31 and 0-4 PHY addresses.
> 
> There are operations where the switch PHY registers are used. For the PHY
> address of the control PHY, transform the MT753X_CTRL_PHY_ADDR constant
> into a macro and use it. The PHY address for the control PHY is 0 when the
> switch listens on 31. In any other case, it is one greater than the PHY
> address the switch listens on.
> 
> Reviewed-by: Daniel Golle <daniel@makrotopia.org>
> Tested-by: Daniel Golle <daniel@makrotopia.org>
> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
> ---
>   drivers/net/dsa/mt7530-mdio.c | 28 ++++++++++++++--------------
>   drivers/net/dsa/mt7530.c      | 35 ++++++++++++++++++++++-------------
>   drivers/net/dsa/mt7530.h      |  4 +++-
>   3 files changed, 39 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
> index 585db03c0548..dc48715f6534 100644
> --- a/drivers/net/dsa/mt7530.h
> +++ b/drivers/net/dsa/mt7530.h
> @@ -625,7 +625,7 @@ enum mt7531_clk_skew {
>   #define  MT7531_PHY_PLL_OFF		BIT(5)
>   #define  MT7531_PHY_PLL_BYPASS_MODE	BIT(4)
>   
> -#define MT753X_CTRL_PHY_ADDR		0
> +#define MT753X_CTRL_PHY_ADDR(phy_addr)	(phy_addr + 1 & 0x1f)

Whilst compiling, GCC suggests parentheses around ‘+’ in operand of ‘&’. I
will send another version in the upcoming days.

Arınç
Florian Fainelli April 15, 2024, 3:30 p.m. UTC | #2
On 4/13/2024 11:07 PM, Arınç ÜNAL via B4 Relay wrote:
> From: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Read the PHY address the switch listens on from the reg property of the
> switch node on the device tree. This change brings support for MT7530
> switches on boards with such bootstrapping configuration where the switch
> listens on a different PHY address than the hardcoded PHY address on the
> driver, 31.
> 
> As described on the "MT7621 Programming Guide v0.4" document, the MT7530
> switch and its PHYs can be configured to listen on the range of 7-12,
> 15-20, 23-28, and 31 and 0-4 PHY addresses.
> 
> There are operations where the switch PHY registers are used. For the PHY
> address of the control PHY, transform the MT753X_CTRL_PHY_ADDR constant
> into a macro and use it. The PHY address for the control PHY is 0 when the
> switch listens on 31. In any other case, it is one greater than the PHY
> address the switch listens on.
> 
> Reviewed-by: Daniel Golle <daniel@makrotopia.org>
> Tested-by: Daniel Golle <daniel@makrotopia.org>
> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>

Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>

I would go a step further and name phy_addr switch_mdio_addr, or 
something along those lines to clearly denote this is not a per-port PHY 
address neither a proper PHY device, but we've already had a similar 
discussion before about spelling this out clearly as a "pseudo PHY"....
Arınç ÜNAL April 16, 2024, 8:32 a.m. UTC | #3
On 15/04/2024 18:30, Florian Fainelli wrote:
> 
> 
> On 4/13/2024 11:07 PM, Arınç ÜNAL via B4 Relay wrote:
>> From: Arınç ÜNAL <arinc.unal@arinc9.com>
>>
>> Read the PHY address the switch listens on from the reg property of the
>> switch node on the device tree. This change brings support for MT7530
>> switches on boards with such bootstrapping configuration where the switch
>> listens on a different PHY address than the hardcoded PHY address on the
>> driver, 31.
>>
>> As described on the "MT7621 Programming Guide v0.4" document, the MT7530
>> switch and its PHYs can be configured to listen on the range of 7-12,
>> 15-20, 23-28, and 31 and 0-4 PHY addresses.
>>
>> There are operations where the switch PHY registers are used. For the PHY
>> address of the control PHY, transform the MT753X_CTRL_PHY_ADDR constant
>> into a macro and use it. The PHY address for the control PHY is 0 when the
>> switch listens on 31. In any other case, it is one greater than the PHY
>> address the switch listens on.
>>
>> Reviewed-by: Daniel Golle <daniel@makrotopia.org>
>> Tested-by: Daniel Golle <daniel@makrotopia.org>
>> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> 
> I would go a step further and name phy_addr switch_mdio_addr, or something along those lines to clearly denote this is not a per-port PHY address neither a proper PHY device, but we've already had a similar discussion before about spelling this out clearly as a "pseudo PHY"....

I am fine with calling the switch operating on an MDIO bus a psuedo-PHY.
But I don't believe this grants making up names on our own instead of using
the name described in IEEE Std 802.3-2022. The switch listens on a PHY
address on the MDIO bus. The description for the phy_addr member of the
mt753x_info structure clearly explains that so I don't see a reason to
change the variable name.

Arınç
Florian Fainelli April 17, 2024, 3:09 a.m. UTC | #4
On 4/16/2024 1:32 AM, Arınç ÜNAL wrote:
> On 15/04/2024 18:30, Florian Fainelli wrote:
>>
>>
>> On 4/13/2024 11:07 PM, Arınç ÜNAL via B4 Relay wrote:
>>> From: Arınç ÜNAL <arinc.unal@arinc9.com>
>>>
>>> Read the PHY address the switch listens on from the reg property of the
>>> switch node on the device tree. This change brings support for MT7530
>>> switches on boards with such bootstrapping configuration where the 
>>> switch
>>> listens on a different PHY address than the hardcoded PHY address on the
>>> driver, 31.
>>>
>>> As described on the "MT7621 Programming Guide v0.4" document, the MT7530
>>> switch and its PHYs can be configured to listen on the range of 7-12,
>>> 15-20, 23-28, and 31 and 0-4 PHY addresses.
>>>
>>> There are operations where the switch PHY registers are used. For the 
>>> PHY
>>> address of the control PHY, transform the MT753X_CTRL_PHY_ADDR constant
>>> into a macro and use it. The PHY address for the control PHY is 0 
>>> when the
>>> switch listens on 31. In any other case, it is one greater than the PHY
>>> address the switch listens on.
>>>
>>> Reviewed-by: Daniel Golle <daniel@makrotopia.org>
>>> Tested-by: Daniel Golle <daniel@makrotopia.org>
>>> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
>>
>> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
>>
>> I would go a step further and name phy_addr switch_mdio_addr, or 
>> something along those lines to clearly denote this is not a per-port 
>> PHY address neither a proper PHY device, but we've already had a 
>> similar discussion before about spelling this out clearly as a "pseudo 
>> PHY"....
> 
> I am fine with calling the switch operating on an MDIO bus a psuedo-PHY.
> But I don't believe this grants making up names on our own instead of using
> the name described in IEEE Std 802.3-2022. The switch listens on a PHY
> address on the MDIO bus. 

The switch listens at a particular address on the MDIO bus, that is the 
key thing. Whether the addressable device happens to be an 
Ethernet/SATA/PCIe/USB PHY, an accelerometer, a light switch or an 
Ethernet switch does not matter as long as it is addressable over clause 
22 and/or 45. For all that matters the switch's MDIO interface is not a 
PHY, otherwise its registers 0-15 would be abiding by the IEEE 
802.3-2022 standard, and that is not the case.

> The description for the phy_addr member of the
> mt753x_info structure clearly explains that so I don't see a reason to
> change the variable name.

IMHO it is clearer to use mdiodev->addr through and through, the 
shorthand is not necessary and does not save that many characters to 
type in the first place. Saving a mdiodev pointer into mt7530_priv and 
accessing priv->mdiodev->addr would be 18 characters to type versus 14 
with priv->phy_addr.

Anyway.
Arınç ÜNAL April 17, 2024, 7:02 a.m. UTC | #5
On 17/04/2024 06:09, Florian Fainelli wrote:
> 
> 
> On 4/16/2024 1:32 AM, Arınç ÜNAL wrote:
>> On 15/04/2024 18:30, Florian Fainelli wrote:
>>> I would go a step further and name phy_addr switch_mdio_addr, or something along those lines to clearly denote this is not a per-port PHY address neither a proper PHY device, but we've already had a similar discussion before about spelling this out clearly as a "pseudo PHY"....
>>
>> I am fine with calling the switch operating on an MDIO bus a psuedo-PHY.
>> But I don't believe this grants making up names on our own instead of using
>> the name described in IEEE Std 802.3-2022. The switch listens on a PHY
>> address on the MDIO bus. 
> 
> The switch listens at a particular address on the MDIO bus, that is the key thing. Whether the addressable device happens to be an Ethernet/SATA/PCIe/USB PHY, an accelerometer, a light switch or an Ethernet switch does not matter as long as it is addressable over clause 22 and/or 45. For all that matters the switch's MDIO interface is not a PHY, otherwise its registers 0-15 would be abiding by the IEEE 802.3-2022 standard, and that is not the case.

I don't deny anything you've said here. I just don't see how this
constitutes making up a different name. The field which the address is
stored is called "PHYAD (PHY Address)". The PHY Address field of the
management frame structure the switch implements is still Clause 22
conformant, as far as I understand.

> 
>> The description for the phy_addr member of the
>> mt753x_info structure clearly explains that so I don't see a reason to
>> change the variable name.
> 
> IMHO it is clearer to use mdiodev->addr through and through, the shorthand is not necessary and does not save that many characters to type in the first place. Saving a mdiodev pointer into mt7530_priv and accessing priv->mdiodev->addr would be 18 characters to type versus 14 with priv->phy_addr.

Fine by me, I can do that.

Arınç
diff mbox series

Patch

diff --git a/drivers/net/dsa/mt7530-mdio.c b/drivers/net/dsa/mt7530-mdio.c
index fa3ee85a99c1..599b28c8a340 100644
--- a/drivers/net/dsa/mt7530-mdio.c
+++ b/drivers/net/dsa/mt7530-mdio.c
@@ -18,7 +18,8 @@ 
 static int
 mt7530_regmap_write(void *context, unsigned int reg, unsigned int val)
 {
-	struct mii_bus *bus = context;
+	struct mt7530_priv *priv = context;
+	struct mii_bus *bus = priv->bus;
 	u16 page, r, lo, hi;
 	int ret;
 
@@ -27,36 +28,35 @@  mt7530_regmap_write(void *context, unsigned int reg, unsigned int val)
 	lo = val & 0xffff;
 	hi = val >> 16;
 
-	/* MT7530 uses 31 as the pseudo port */
-	ret = bus->write(bus, 0x1f, 0x1f, page);
+	ret = bus->write(bus, priv->phy_addr, 0x1f, page);
 	if (ret < 0)
 		return ret;
 
-	ret = bus->write(bus, 0x1f, r,  lo);
+	ret = bus->write(bus, priv->phy_addr, r, lo);
 	if (ret < 0)
 		return ret;
 
-	ret = bus->write(bus, 0x1f, 0x10, hi);
+	ret = bus->write(bus, priv->phy_addr, 0x10, hi);
 	return ret;
 }
 
 static int
 mt7530_regmap_read(void *context, unsigned int reg, unsigned int *val)
 {
-	struct mii_bus *bus = context;
+	struct mt7530_priv *priv = context;
+	struct mii_bus *bus = priv->bus;
 	u16 page, r, lo, hi;
 	int ret;
 
 	page = (reg >> 6) & 0x3ff;
 	r = (reg >> 2) & 0xf;
 
-	/* MT7530 uses 31 as the pseudo port */
-	ret = bus->write(bus, 0x1f, 0x1f, page);
+	ret = bus->write(bus, priv->phy_addr, 0x1f, page);
 	if (ret < 0)
 		return ret;
 
-	lo = bus->read(bus, 0x1f, r);
-	hi = bus->read(bus, 0x1f, 0x10);
+	lo = bus->read(bus, priv->phy_addr, r);
+	hi = bus->read(bus, priv->phy_addr, 0x10);
 
 	*val = (hi << 16) | (lo & 0xffff);
 
@@ -107,8 +107,7 @@  mt7531_create_sgmii(struct mt7530_priv *priv)
 		mt7531_pcs_config[i]->unlock = mt7530_mdio_regmap_unlock;
 		mt7531_pcs_config[i]->lock_arg = &priv->bus->mdio_lock;
 
-		regmap = devm_regmap_init(priv->dev,
-					  &mt7530_regmap_bus, priv->bus,
+		regmap = devm_regmap_init(priv->dev, &mt7530_regmap_bus, priv,
 					  mt7531_pcs_config[i]);
 		if (IS_ERR(regmap)) {
 			ret = PTR_ERR(regmap);
@@ -153,6 +152,7 @@  mt7530_probe(struct mdio_device *mdiodev)
 
 	priv->bus = mdiodev->bus;
 	priv->dev = &mdiodev->dev;
+	priv->phy_addr = mdiodev->addr;
 
 	ret = mt7530_probe_common(priv);
 	if (ret)
@@ -203,8 +203,8 @@  mt7530_probe(struct mdio_device *mdiodev)
 	regmap_config->reg_stride = 4;
 	regmap_config->max_register = MT7530_CREV;
 	regmap_config->disable_locking = true;
-	priv->regmap = devm_regmap_init(priv->dev, &mt7530_regmap_bus,
-					priv->bus, regmap_config);
+	priv->regmap = devm_regmap_init(priv->dev, &mt7530_regmap_bus, priv,
+					regmap_config);
 	if (IS_ERR(priv->regmap))
 		return PTR_ERR(priv->regmap);
 
diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index c0d0bce0b594..fefa6dd151fa 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -86,22 +86,26 @@  core_read_mmd_indirect(struct mt7530_priv *priv, int prtad, int devad)
 	int value, ret;
 
 	/* Write the desired MMD Devad */
-	ret = bus->write(bus, 0, MII_MMD_CTRL, devad);
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_CTRL, devad);
 	if (ret < 0)
 		goto err;
 
 	/* Write the desired MMD register address */
-	ret = bus->write(bus, 0, MII_MMD_DATA, prtad);
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_DATA, prtad);
 	if (ret < 0)
 		goto err;
 
 	/* Select the Function : DATA with no post increment */
-	ret = bus->write(bus, 0, MII_MMD_CTRL, (devad | MII_MMD_CTRL_NOINCR));
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_CTRL, devad | MII_MMD_CTRL_NOINCR);
 	if (ret < 0)
 		goto err;
 
 	/* Read the content of the MMD's selected register */
-	value = bus->read(bus, 0, MII_MMD_DATA);
+	value = bus->read(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			  MII_MMD_DATA);
 
 	return value;
 err:
@@ -118,22 +122,26 @@  core_write_mmd_indirect(struct mt7530_priv *priv, int prtad,
 	int ret;
 
 	/* Write the desired MMD Devad */
-	ret = bus->write(bus, 0, MII_MMD_CTRL, devad);
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_CTRL, devad);
 	if (ret < 0)
 		goto err;
 
 	/* Write the desired MMD register address */
-	ret = bus->write(bus, 0, MII_MMD_DATA, prtad);
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_DATA, prtad);
 	if (ret < 0)
 		goto err;
 
 	/* Select the Function : DATA with no post increment */
-	ret = bus->write(bus, 0, MII_MMD_CTRL, (devad | MII_MMD_CTRL_NOINCR));
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_CTRL, devad | MII_MMD_CTRL_NOINCR);
 	if (ret < 0)
 		goto err;
 
 	/* Write the data into MMD's selected register */
-	ret = bus->write(bus, 0, MII_MMD_DATA, data);
+	ret = bus->write(bus, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+			 MII_MMD_DATA, data);
 err:
 	if (ret < 0)
 		dev_err(&bus->dev,
@@ -2671,16 +2679,17 @@  mt7531_setup(struct dsa_switch *ds)
 	 * phy_[read,write]_mmd_indirect is called, we provide our own
 	 * mt7531_ind_mmd_phy_[read,write] to complete this function.
 	 */
-	val = mt7531_ind_c45_phy_read(priv, MT753X_CTRL_PHY_ADDR,
+	val = mt7531_ind_c45_phy_read(priv,
+				      MT753X_CTRL_PHY_ADDR(priv->phy_addr),
 				      MDIO_MMD_VEND2, CORE_PLL_GROUP4);
 	val |= MT7531_RG_SYSPLL_DMY2 | MT7531_PHY_PLL_BYPASS_MODE;
 	val &= ~MT7531_PHY_PLL_OFF;
-	mt7531_ind_c45_phy_write(priv, MT753X_CTRL_PHY_ADDR, MDIO_MMD_VEND2,
-				 CORE_PLL_GROUP4, val);
+	mt7531_ind_c45_phy_write(priv, MT753X_CTRL_PHY_ADDR(priv->phy_addr),
+				 MDIO_MMD_VEND2, CORE_PLL_GROUP4, val);
 
 	/* Disable EEE advertisement on the switch PHYs. */
-	for (i = MT753X_CTRL_PHY_ADDR;
-	     i < MT753X_CTRL_PHY_ADDR + MT7530_NUM_PHYS; i++) {
+	for (i = MT753X_CTRL_PHY_ADDR(priv->phy_addr);
+	     i < MT753X_CTRL_PHY_ADDR(priv->phy_addr) + MT7530_NUM_PHYS; i++) {
 		mt7531_ind_c45_phy_write(priv, i, MDIO_MMD_AN, MDIO_AN_EEE_ADV,
 					 0);
 	}
diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
index 585db03c0548..dc48715f6534 100644
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -625,7 +625,7 @@  enum mt7531_clk_skew {
 #define  MT7531_PHY_PLL_OFF		BIT(5)
 #define  MT7531_PHY_PLL_BYPASS_MODE	BIT(4)
 
-#define MT753X_CTRL_PHY_ADDR		0
+#define MT753X_CTRL_PHY_ADDR(phy_addr)	(phy_addr + 1 & 0x1f)
 
 #define CORE_PLL_GROUP5			0x404
 #define  RG_LCDDS_PCW_NCPO1(x)		((x) & 0xffff)
@@ -774,6 +774,7 @@  struct mt753x_info {
  * @irq_enable:		IRQ enable bits, synced to SYS_INT_EN
  * @create_sgmii:	Pointer to function creating SGMII PCS instance(s)
  * @active_cpu_ports:	Holding the active CPU ports
+ * @phy_addr:		Holding the PHY address the switch listens on
  */
 struct mt7530_priv {
 	struct device		*dev;
@@ -800,6 +801,7 @@  struct mt7530_priv {
 	u32 irq_enable;
 	int (*create_sgmii)(struct mt7530_priv *priv);
 	u8 active_cpu_ports;
+	int phy_addr;
 };
 
 struct mt7530_hw_vlan_entry {