[PATCH net-next 0/3] net: phy: realtek: add support for integrated 2.5Gbps PHY in RTL8125

[PATCH net-next 0/3] net: phy: realtek: add support for integrated 2.5Gbps PHY in RTL8125

[Heiner Kallweit]

This series adds support for the integrated 2.5Gbps PHY in RTL8125.
First two patches add necessary functionality to phylib.

Heiner Kallweit (3):
  net: phy: prepare phylib to deal with PHY's extending Clause 22
  net: phy: add phy_modify_paged_changed
  net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

 drivers/net/phy/phy-core.c   | 29 ++++++++++++++++++----
 drivers/net/phy/phy_device.c | 35 +++++++++++---------------
 drivers/net/phy/realtek.c    | 48 ++++++++++++++++++++++++++++++++++++
 include/linux/phy.h          | 10 +++++++-
 4 files changed, 96 insertions(+), 26 deletions(-)

-- 
2.22.0

[PATCH net-next 1/3] net: phy: prepare phylib to deal with PHY's extending Clause 22

[Heiner Kallweit]

The integrated PHY in 2.5Gbps chip RTL8125 is the first (known to me)
PHY that uses standard Clause 22 for all modes up to 1Gbps and adds
2.5Gbps control using vendor-specific registers. To use phylib for
the standard part little extensions are needed:
- Move most of genphy_config_aneg to a new function
  __genphy_config_aneg that takes a parameter whether restarting
  auto-negotiation is needed (depending on whether content of
  vendor-specific advertisement register changed).
- Don't clear phydev->lp_advertising in genphy_read_status so that
  we can set non-C22 mode flags before.

Basically both changes mimic the behavior of the equivalent Clause 45
functions.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/phy_device.c | 35 +++++++++++++++--------------------
 include/linux/phy.h          |  8 +++++++-
 2 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 7ddd91df9..bd7e7db8c 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1571,11 +1571,9 @@ static int genphy_config_advert(struct phy_device *phydev)
 	/* Only allow advertising what this PHY supports */
 	linkmode_and(phydev->advertising, phydev->advertising,
 		     phydev->supported);
-	if (!ethtool_convert_link_mode_to_legacy_u32(&advertise,
-						     phydev->advertising))
-		phydev_warn(phydev, "PHY advertising (%*pb) more modes than genphy supports, some modes not advertised.\n",
-			    __ETHTOOL_LINK_MODE_MASK_NBITS,
-			    phydev->advertising);
+
+	ethtool_convert_link_mode_to_legacy_u32(&advertise,
+						phydev->advertising);
 
 	/* Setup standard advertisement */
 	err = phy_modify_changed(phydev, MII_ADVERTISE,
@@ -1681,18 +1679,20 @@ int genphy_restart_aneg(struct phy_device *phydev)
 EXPORT_SYMBOL(genphy_restart_aneg);
 
 /**
- * genphy_config_aneg - restart auto-negotiation or write BMCR
+ * __genphy_config_aneg - restart auto-negotiation or write BMCR
  * @phydev: target phy_device struct
+ * @changed: whether autoneg is requested
  *
  * Description: If auto-negotiation is enabled, we configure the
  *   advertising, and then restart auto-negotiation.  If it is not
  *   enabled, then we write the BMCR.
  */
-int genphy_config_aneg(struct phy_device *phydev)
+int __genphy_config_aneg(struct phy_device *phydev, bool changed)
 {
-	int err, changed;
+	int err;
 
-	changed = genphy_config_eee_advert(phydev);
+	if (genphy_config_eee_advert(phydev))
+		changed = true;
 
 	if (AUTONEG_ENABLE != phydev->autoneg)
 		return genphy_setup_forced(phydev);
@@ -1700,10 +1700,10 @@ int genphy_config_aneg(struct phy_device *phydev)
 	err = genphy_config_advert(phydev);
 	if (err < 0) /* error */
 		return err;
+	else if (err)
+		changed = true;
 
-	changed |= err;
-
-	if (changed == 0) {
+	if (!changed) {
 		/* Advertisement hasn't changed, but maybe aneg was never on to
 		 * begin with?  Or maybe phy was isolated?
 		 */
@@ -1713,18 +1713,15 @@ int genphy_config_aneg(struct phy_device *phydev)
 			return ctl;
 
 		if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE))
-			changed = 1; /* do restart aneg */
+			changed = true; /* do restart aneg */
 	}
 
 	/* Only restart aneg if we are advertising something different
 	 * than we were before.
 	 */
-	if (changed > 0)
-		return genphy_restart_aneg(phydev);
-
-	return 0;
+	return changed ? genphy_restart_aneg(phydev) : 0;
 }
-EXPORT_SYMBOL(genphy_config_aneg);
+EXPORT_SYMBOL(__genphy_config_aneg);
 
 /**
  * genphy_aneg_done - return auto-negotiation status
@@ -1811,8 +1808,6 @@ int genphy_read_status(struct phy_device *phydev)
 	phydev->pause = 0;
 	phydev->asym_pause = 0;
 
-	linkmode_zero(phydev->lp_advertising);
-
 	if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
 		if (phydev->is_gigabit_capable) {
 			lpagb = phy_read(phydev, MII_STAT1000);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 462b90b73..7117825ee 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1069,7 +1069,7 @@ int genphy_read_abilities(struct phy_device *phydev);
 int genphy_setup_forced(struct phy_device *phydev);
 int genphy_restart_aneg(struct phy_device *phydev);
 int genphy_config_eee_advert(struct phy_device *phydev);
-int genphy_config_aneg(struct phy_device *phydev);
+int __genphy_config_aneg(struct phy_device *phydev, bool changed);
 int genphy_aneg_done(struct phy_device *phydev);
 int genphy_update_link(struct phy_device *phydev);
 int genphy_read_status(struct phy_device *phydev);
@@ -1077,6 +1077,12 @@ int genphy_suspend(struct phy_device *phydev);
 int genphy_resume(struct phy_device *phydev);
 int genphy_loopback(struct phy_device *phydev, bool enable);
 int genphy_soft_reset(struct phy_device *phydev);
+
+static inline int genphy_config_aneg(struct phy_device *phydev)
+{
+	return __genphy_config_aneg(phydev, false);
+}
+
 static inline int genphy_no_soft_reset(struct phy_device *phydev)
 {
 	return 0;
-- 
2.22.0

[PATCH net-next 2/3] net: phy: add phy_modify_paged_changed

[Heiner Kallweit]

Add helper function phy_modify_paged_changed, behavior is the same
as for phy_modify_changed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/phy-core.c | 29 ++++++++++++++++++++++++-----
 include/linux/phy.h        |  2 ++
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
index 16667fbac..9ae3abb2d 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -783,24 +783,43 @@ int phy_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val)
 EXPORT_SYMBOL(phy_write_paged);
 
 /**
- * phy_modify_paged() - Convenience function for modifying a paged register
+ * phy_modify_paged_changed() - Function for modifying a paged register
  * @phydev: a pointer to a &struct phy_device
  * @page: the page for the phy
  * @regnum: register number
  * @mask: bit mask of bits to clear
  * @set: bit mask of bits to set
  *
- * Same rules as for phy_read() and phy_write().
+ * Returns negative errno, 0 if there was no change, and 1 in case of change
  */
-int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
-		     u16 mask, u16 set)
+int phy_modify_paged_changed(struct phy_device *phydev, int page, u32 regnum,
+			     u16 mask, u16 set)
 {
 	int ret = 0, oldpage;
 
 	oldpage = phy_select_page(phydev, page);
 	if (oldpage >= 0)
-		ret = __phy_modify(phydev, regnum, mask, set);
+		ret = __phy_modify_changed(phydev, regnum, mask, set);
 
 	return phy_restore_page(phydev, oldpage, ret);
 }
+EXPORT_SYMBOL(phy_modify_paged_changed);
+
+/**
+ * phy_modify_paged() - Convenience function for modifying a paged register
+ * @phydev: a pointer to a &struct phy_device
+ * @page: the page for the phy
+ * @regnum: register number
+ * @mask: bit mask of bits to clear
+ * @set: bit mask of bits to set
+ *
+ * Same rules as for phy_read() and phy_write().
+ */
+int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
+		     u16 mask, u16 set)
+{
+	int ret = phy_modify_paged_changed(phydev, page, regnum, mask, set);
+
+	return ret < 0 ? ret : 0;
+}
 EXPORT_SYMBOL(phy_modify_paged);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 7117825ee..781f4810c 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -984,6 +984,8 @@ int phy_select_page(struct phy_device *phydev, int page);
 int phy_restore_page(struct phy_device *phydev, int oldpage, int ret);
 int phy_read_paged(struct phy_device *phydev, int page, u32 regnum);
 int phy_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val);
+int phy_modify_paged_changed(struct phy_device *phydev, int page, u32 regnum,
+			     u16 mask, u16 set);
 int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
 		     u16 mask, u16 set);
 
-- 
2.22.0

[PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Heiner Kallweit]

This adds support for the integrated 2.5Gbps PHY in Realtek RTL8125.
Advertisement of 2.5Gbps mode is done via a vendor-specific register.
Same applies to reading NBase-T link partner advertisement.
Unfortunately this 2.5Gbps PHY shares the PHY ID with the integrated
1Gbps PHY's in other Realtek network chips and so far no method is
known to differentiate them. This means we can't autodetect 2.5Gbps
support and the network driver has to add 2.5Gbps to the supported
and advertised modes.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/realtek.c | 48 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index a669945eb..35c981476 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -39,6 +39,11 @@
 #define RTL8366RB_POWER_SAVE			0x15
 #define RTL8366RB_POWER_SAVE_ON			BIT(12)
 
+#define RTL_ADV_2500FULL			BIT(7)
+#define RTL_LPADV_10000FULL			BIT(11)
+#define RTL_LPADV_5000FULL			BIT(6)
+#define RTL_LPADV_2500FULL			BIT(5)
+
 MODULE_DESCRIPTION("Realtek PHY driver");
 MODULE_AUTHOR("Johnson Leung");
 MODULE_LICENSE("GPL");
@@ -256,6 +261,47 @@ static int rtl8366rb_config_init(struct phy_device *phydev)
 	return ret;
 }
 
+static int rtlgen_config_aneg(struct phy_device *phydev)
+{
+	int ret = 0;
+
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
+	    phydev->supported) && phydev->autoneg == AUTONEG_ENABLE) {
+		u16 adv2500 = 0;
+
+		if (linkmode_test_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
+				      phydev->advertising))
+			adv2500 = RTL_ADV_2500FULL;
+
+		ret = phy_modify_paged_changed(phydev, 0xa5d, 0x12,
+					       RTL_ADV_2500FULL, adv2500);
+		if (ret < 0)
+			return ret;
+	}
+
+	return __genphy_config_aneg(phydev, ret);
+}
+
+static int rtlgen_read_status(struct phy_device *phydev)
+{
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
+	    phydev->supported) && phydev->autoneg == AUTONEG_ENABLE) {
+		int lpadv = phy_read_paged(phydev, 0xa5d, 0x13);
+
+		if (lpadv < 0)
+			return lpadv;
+
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
+			phydev->lp_advertising, lpadv & RTL_LPADV_10000FULL);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_5000baseT_Full_BIT,
+			phydev->lp_advertising, lpadv & RTL_LPADV_5000FULL);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
+			phydev->lp_advertising, lpadv & RTL_LPADV_2500FULL);
+	}
+
+	return genphy_read_status(phydev);
+}
+
 static struct phy_driver realtek_drvs[] = {
 	{
 		PHY_ID_MATCH_EXACT(0x00008201),
@@ -328,6 +374,8 @@ static struct phy_driver realtek_drvs[] = {
 	}, {
 		PHY_ID_MATCH_EXACT(0x001cc800),
 		.name		= "Generic Realtek PHY",
+		.config_aneg	= rtlgen_config_aneg,
+		.read_status	= rtlgen_read_status,
 		.suspend	= genphy_suspend,
 		.resume		= genphy_resume,
 		.read_page	= rtl821x_read_page,
-- 
2.22.0

Re: [PATCH net-next 1/3] net: phy: prepare phylib to deal with PHY's extending Clause 22

[Andrew Lunn]

On Thu, Aug 08, 2019 at 09:03:42PM +0200, Heiner Kallweit wrote:
> The integrated PHY in 2.5Gbps chip RTL8125 is the first (known to me)
> PHY that uses standard Clause 22 for all modes up to 1Gbps and adds
> 2.5Gbps control using vendor-specific registers. To use phylib for
> the standard part little extensions are needed:
> - Move most of genphy_config_aneg to a new function
>   __genphy_config_aneg that takes a parameter whether restarting
>   auto-negotiation is needed (depending on whether content of
>   vendor-specific advertisement register changed).
> - Don't clear phydev->lp_advertising in genphy_read_status so that
>   we can set non-C22 mode flags before.
> 
> Basically both changes mimic the behavior of the equivalent Clause 45
> functions.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/net/phy/phy_device.c | 35 +++++++++++++++--------------------
>  include/linux/phy.h          |  8 +++++++-
>  2 files changed, 22 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 7ddd91df9..bd7e7db8c 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -1571,11 +1571,9 @@ static int genphy_config_advert(struct phy_device *phydev)
>  	/* Only allow advertising what this PHY supports */
>  	linkmode_and(phydev->advertising, phydev->advertising,
>  		     phydev->supported);
> -	if (!ethtool_convert_link_mode_to_legacy_u32(&advertise,
> -						     phydev->advertising))
> -		phydev_warn(phydev, "PHY advertising (%*pb) more modes than genphy supports, some modes not advertised.\n",
> -			    __ETHTOOL_LINK_MODE_MASK_NBITS,
> -			    phydev->advertising);
> +
> +	ethtool_convert_link_mode_to_legacy_u32(&advertise,
> +						phydev->advertising);

Hi Heiner

linkmode_adv_to_mii_adv_t() would remove the need to use
ethtool_convert_link_mode_to_legacy_u32(), and this warning would also
go away. 

   Andrew

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Andrew Lunn]

On Thu, Aug 08, 2019 at 09:05:54PM +0200, Heiner Kallweit wrote:
> This adds support for the integrated 2.5Gbps PHY in Realtek RTL8125.
> Advertisement of 2.5Gbps mode is done via a vendor-specific register.
> Same applies to reading NBase-T link partner advertisement.
> Unfortunately this 2.5Gbps PHY shares the PHY ID with the integrated
> 1Gbps PHY's in other Realtek network chips and so far no method is
> known to differentiate them.

That is not nice.

Do you have any contacts in Realtek who can provide us with
information? Maybe there is another undocumented vendor specific
register?

	Andrew

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Heiner Kallweit]

On 08.08.2019 21:37, Andrew Lunn wrote:
> On Thu, Aug 08, 2019 at 09:05:54PM +0200, Heiner Kallweit wrote:
>> This adds support for the integrated 2.5Gbps PHY in Realtek RTL8125.
>> Advertisement of 2.5Gbps mode is done via a vendor-specific register.
>> Same applies to reading NBase-T link partner advertisement.
>> Unfortunately this 2.5Gbps PHY shares the PHY ID with the integrated
>> 1Gbps PHY's in other Realtek network chips and so far no method is
>> known to differentiate them.
> 
> That is not nice.
> 
Indeed.

> Do you have any contacts in Realtek who can provide us with
> information? Maybe there is another undocumented vendor specific
> register?
> 
I have a contact in Realtek who provided the information about
the vendor-specific registers used in the patch. I also asked for
a method to auto-detect 2.5Gbps support but have no feedback so far.
What may contribute to the problem is that also the integrated 1Gbps
PHY's (all with the same PHY ID) differ significantly from each other,
depending on the network chip version.

> 	Andrew
> 
Heiner

Re: [PATCH net-next 1/3] net: phy: prepare phylib to deal with PHY's extending Clause 22

[Heiner Kallweit]

On 08.08.2019 21:32, Andrew Lunn wrote:
> On Thu, Aug 08, 2019 at 09:03:42PM +0200, Heiner Kallweit wrote:
>> The integrated PHY in 2.5Gbps chip RTL8125 is the first (known to me)
>> PHY that uses standard Clause 22 for all modes up to 1Gbps and adds
>> 2.5Gbps control using vendor-specific registers. To use phylib for
>> the standard part little extensions are needed:
>> - Move most of genphy_config_aneg to a new function
>>   __genphy_config_aneg that takes a parameter whether restarting
>>   auto-negotiation is needed (depending on whether content of
>>   vendor-specific advertisement register changed).
>> - Don't clear phydev->lp_advertising in genphy_read_status so that
>>   we can set non-C22 mode flags before.
>>
>> Basically both changes mimic the behavior of the equivalent Clause 45
>> functions.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> ---
>>  drivers/net/phy/phy_device.c | 35 +++++++++++++++--------------------
>>  include/linux/phy.h          |  8 +++++++-
>>  2 files changed, 22 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
>> index 7ddd91df9..bd7e7db8c 100644
>> --- a/drivers/net/phy/phy_device.c
>> +++ b/drivers/net/phy/phy_device.c
>> @@ -1571,11 +1571,9 @@ static int genphy_config_advert(struct phy_device *phydev)
>>  	/* Only allow advertising what this PHY supports */
>>  	linkmode_and(phydev->advertising, phydev->advertising,
>>  		     phydev->supported);
>> -	if (!ethtool_convert_link_mode_to_legacy_u32(&advertise,
>> -						     phydev->advertising))
>> -		phydev_warn(phydev, "PHY advertising (%*pb) more modes than genphy supports, some modes not advertised.\n",
>> -			    __ETHTOOL_LINK_MODE_MASK_NBITS,
>> -			    phydev->advertising);
>> +
>> +	ethtool_convert_link_mode_to_legacy_u32(&advertise,
>> +						phydev->advertising);
> 
> Hi Heiner
> 
> linkmode_adv_to_mii_adv_t() would remove the need to use
> ethtool_convert_link_mode_to_legacy_u32(), and this warning would also
> go away. 
> 
Thanks for the hint! I'll check and submit a v2.

>    Andrew
> 
Heiner

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Andrew Lunn]

> I have a contact in Realtek who provided the information about
> the vendor-specific registers used in the patch. I also asked for
> a method to auto-detect 2.5Gbps support but have no feedback so far.
> What may contribute to the problem is that also the integrated 1Gbps
> PHY's (all with the same PHY ID) differ significantly from each other,
> depending on the network chip version.

Hi Heiner

Some of the PHYs embedded in Marvell switches have an OUI, but no
product ID. We work around this brokenness by trapping the reads to
the ID registers in the MDIO bus controller driver and inserting the
switch product ID. The Marvell PHY driver then recognises these IDs
and does the right thing.

Maybe you can do something similar here?

      Andrew

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Heiner Kallweit]

On 08.08.2019 22:20, Andrew Lunn wrote:
>> I have a contact in Realtek who provided the information about
>> the vendor-specific registers used in the patch. I also asked for
>> a method to auto-detect 2.5Gbps support but have no feedback so far.
>> What may contribute to the problem is that also the integrated 1Gbps
>> PHY's (all with the same PHY ID) differ significantly from each other,
>> depending on the network chip version.
> 
> Hi Heiner
> 
> Some of the PHYs embedded in Marvell switches have an OUI, but no
> product ID. We work around this brokenness by trapping the reads to
> the ID registers in the MDIO bus controller driver and inserting the
> switch product ID. The Marvell PHY driver then recognises these IDs
> and does the right thing.
> 
> Maybe you can do something similar here?
> 
Yes, this would be an idea. Let me check.

>       Andrew
> 
Thanks, Heiner

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Florian Fainelli]

On 8/8/2019 1:24 PM, Heiner Kallweit wrote:
> On 08.08.2019 22:20, Andrew Lunn wrote:
>>> I have a contact in Realtek who provided the information about
>>> the vendor-specific registers used in the patch. I also asked for
>>> a method to auto-detect 2.5Gbps support but have no feedback so far.
>>> What may contribute to the problem is that also the integrated 1Gbps
>>> PHY's (all with the same PHY ID) differ significantly from each other,
>>> depending on the network chip version.
>>
>> Hi Heiner
>>
>> Some of the PHYs embedded in Marvell switches have an OUI, but no
>> product ID. We work around this brokenness by trapping the reads to
>> the ID registers in the MDIO bus controller driver and inserting the
>> switch product ID. The Marvell PHY driver then recognises these IDs
>> and does the right thing.
>>
>> Maybe you can do something similar here?
>>
> Yes, this would be an idea. Let me check.

Since this is an integrated PHY you could have the MAC driver pass a
specific phydev->dev_flag bit that indicates that this is RTL8215, since
I am assuming that PCI IDs for those different chipsets do have to be
allocated, right?
-- 
Florian

Re: [PATCH net-next 3/3] net: phy: realtek: add support for the 2.5Gbps PHY in RTL8125

[Heiner Kallweit]

On 02.09.2019 04:07, Florian Fainelli wrote:
> 
> 
> On 8/8/2019 1:24 PM, Heiner Kallweit wrote:
>> On 08.08.2019 22:20, Andrew Lunn wrote:
>>>> I have a contact in Realtek who provided the information about
>>>> the vendor-specific registers used in the patch. I also asked for
>>>> a method to auto-detect 2.5Gbps support but have no feedback so far.
>>>> What may contribute to the problem is that also the integrated 1Gbps
>>>> PHY's (all with the same PHY ID) differ significantly from each other,
>>>> depending on the network chip version.
>>>
>>> Hi Heiner
>>>
>>> Some of the PHYs embedded in Marvell switches have an OUI, but no
>>> product ID. We work around this brokenness by trapping the reads to
>>> the ID registers in the MDIO bus controller driver and inserting the
>>> switch product ID. The Marvell PHY driver then recognises these IDs
>>> and does the right thing.
>>>
>>> Maybe you can do something similar here?
>>>
>> Yes, this would be an idea. Let me check.
> 
> Since this is an integrated PHY you could have the MAC driver pass a
> specific phydev->dev_flag bit that indicates that this is RTL8215, since
> I am assuming that PCI IDs for those different chipsets do have to be
> allocated, right?
> 
Hi Florian,

thanks for the feedback. In the meantime Realtek provided a method to
identify NBaseT-capable PHY's, and the respective match_phy_device
callback implementations had been done in
5181b473d64e ("net: phy: realtek: add NBase-T PHY auto-detection").

Heiner