Re: [PATCH net-next v4 2/2] net: phy: broadcom: add 1000Base-X support for BCM54616S

[Tao Ren]

On 8/6/19 3:00 PM, Heiner Kallweit wrote:
> On 06.08.2019 23:09, Tao Ren wrote:
>> The BCM54616S PHY cannot work properly in RGMII->1000Base-KX mode (for
>> example, on Facebook CMM BMC platform), mainly because genphy functions
>> are designed for copper links, and 1000Base-X (clause 37) auto negotiation
>> needs to be handled differently.
>>
>> This patch enables 1000Base-X support for BCM54616S by customizing 3
>> driver callbacks:
>>
>>   - probe: probe callback detects PHY's operation mode based on
>>     INTERF_SEL[1:0] pins and 1000X/100FX selection bit in SerDES 100-FX
>>     Control register.
>>
>>   - config_aneg: bcm54616s_config_aneg_1000bx function is added for auto
>>     negotiation in 1000Base-X mode.
>>
>>   - read_status: BCM54616S and BCM5482 PHY share the same read_status
>>     callback which manually set link speed and duplex mode in 1000Base-X
>>     mode.
>>
>> Signed-off-by: Tao Ren <taoren@xxxxxx>
>> ---
>>  Changes in v4:
>>   - add bcm54616s_config_aneg_1000bx() to deal with auto negotiation in
>>     1000Base-X mode.
>>  Changes in v3:
>>   - rename bcm5482_read_status to bcm54xx_read_status so the callback can
>>     be shared by BCM5482 and BCM54616S.
>>  Changes in v2:
>>   - Auto-detect PHY operation mode instead of passing DT node.
>>   - move PHY mode auto-detect logic from config_init to probe callback.
>>   - only set speed (not including duplex) in read_status callback.
>>   - update patch description with more background to avoid confusion.
>>   - patch #1 in the series ("net: phy: broadcom: set features explicitly
>>     for BCM54616") is dropped: the fix should go to get_features callback
>>     which may potentially depend on this patch.
>>
>>  drivers/net/phy/broadcom.c | 62 ++++++++++++++++++++++++++++++++++----
>>  include/linux/brcmphy.h    | 10 ++++--
>>  2 files changed, 64 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
>> index 937d0059e8ac..bf61ed8451e5 100644
>> --- a/drivers/net/phy/broadcom.c
>> +++ b/drivers/net/phy/broadcom.c
>> @@ -383,9 +383,9 @@ static int bcm5482_config_init(struct phy_device *phydev)
>>  		/*
>>  		 * Select 1000BASE-X register set (primary SerDes)
>>  		 */
>> -		reg = bcm_phy_read_shadow(phydev, BCM5482_SHD_MODE);
>> -		bcm_phy_write_shadow(phydev, BCM5482_SHD_MODE,
>> -				     reg | BCM5482_SHD_MODE_1000BX);
>> +		reg = bcm_phy_read_shadow(phydev, BCM54XX_SHD_MODE);
>> +		bcm_phy_write_shadow(phydev, BCM54XX_SHD_MODE,
>> +				     reg | BCM54XX_SHD_MODE_1000BX);
>>  
>>  		/*
>>  		 * LED1=ACTIVITYLED, LED3=LINKSPD[2]
>> @@ -409,7 +409,7 @@ static int bcm5482_config_init(struct phy_device *phydev)
>>  	return err;
>>  }
>>  
>> -static int bcm5482_read_status(struct phy_device *phydev)
>> +static int bcm54xx_read_status(struct phy_device *phydev)
>>  {
>>  	int err;
>>  
>> @@ -451,12 +451,60 @@ static int bcm5481_config_aneg(struct phy_device *phydev)
>>  	return ret;
>>  }
>>  
>> +static int bcm54616s_probe(struct phy_device *phydev)
>> +{
>> +	int val, intf_sel;
>> +
>> +	val = bcm_phy_read_shadow(phydev, BCM54XX_SHD_MODE);
>> +	if (val < 0)
>> +		return val;
>> +
>> +	/* The PHY is strapped in RGMII to fiber mode when INTERF_SEL[1:0]
>> +	 * is 01b.
>> +	 */
>> +	intf_sel = (val & BCM54XX_SHD_INTF_SEL_MASK) >> 1;
>> +	if (intf_sel == 1) {
>> +		val = bcm_phy_read_shadow(phydev, BCM54616S_SHD_100FX_CTRL);
>> +		if (val < 0)
>> +			return val;
>> +
>> +		/* Bit 0 of the SerDes 100-FX Control register, when set
>> +		 * to 1, sets the MII/RGMII -> 100BASE-FX configuration.
>> +		 * When this bit is set to 0, it sets the GMII/RGMII ->
>> +		 * 1000BASE-X configuration.
>> +		 */
>> +		if (!(val & BCM54616S_100FX_MODE))
>> +			phydev->dev_flags |= PHY_BCM_FLAGS_MODE_1000BX;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm54616s_config_aneg_1000bx(struct phy_device *phydev)
>> +{
>> +	int err;
>> +	int adv = 0;
>> +
>> +	if (linkmode_test_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
>> +			      phydev->supported))
>> +		adv |= ADVERTISE_1000XFULL;
>> +
>> +	err = phy_modify_changed(phydev, MII_ADVERTISE, 0, adv);
> 
> The "0" parameter is wrong, it must be ADVERTISE_1000XFULL.
> First you reset the bit, and then you set it or not.

Got it. Will fix it in patch v5. Thanks.

>> +	if (err > 0)
>> +		err = genphy_restart_aneg(phydev);
>> +
>> +	return err;
>> +}
>> +
>>  static int bcm54616s_config_aneg(struct phy_device *phydev)
>>  {
>>  	int ret;
>>  
>>  	/* Aneg firsly. */
>> -	ret = genphy_config_aneg(phydev);
>> +	if (phydev->dev_flags & PHY_BCM_FLAGS_MODE_1000BX)
>> +		ret = bcm54616s_config_aneg_1000bx(phydev);
>> +	else
>> +		ret = genphy_config_aneg(phydev);
>>  
>>  	/* Then we can set up the delay. */
>>  	bcm54xx_config_clock_delay(phydev);
>> @@ -655,6 +703,8 @@ static struct phy_driver broadcom_drivers[] = {
>>  	.config_aneg	= bcm54616s_config_aneg,
>>  	.ack_interrupt	= bcm_phy_ack_intr,
>>  	.config_intr	= bcm_phy_config_intr,
>> +	.read_status	= bcm54xx_read_status,
> 
> If you use aneg, you should also read what was negotiated.
> But this function reads neither negotiated duplex mode nor
> pause settings.

Let me see how to fix it.. Will come back soon..


Thanks,

Tao