Re: [PATCH net-next v7 3/3] net: phy: broadcom: add 1000Base-X support for BCM54616S

From: Tao Ren
Date: Thu Aug 15 2019 - 19:13:38 EST


Hi Andrew / Florian / Heiner / Vladimir,

Any further suggestions on the patch series?


Thanks,

Tao

On 8/11/19 4:40 PM, Tao Ren wrote:
> The BCM54616S PHY cannot work properly in RGMII->1000Base-X mode, 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, and it's verified to be working on Facebook CMM BMC
> platform (RGMII->1000Base-KX):
>
> - 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: calls genphy_c37_config_aneg when the PHY is running in
> 1000Base-X mode; otherwise, genphy_config_aneg will be called.
>
> - read_status: calls genphy_c37_read_status when the PHY is running in
> 1000Base-X mode; otherwise, genphy_read_status will be called.
>
> Note: BCM54616S PHY can also be configured in RGMII->100Base-FX mode, and
> 100Base-FX support is not available as of now.
>
> Signed-off-by: Tao Ren <taoren@xxxxxx>
> ---
> Changes in v7:
> - Add comment "BCM54616S 100Base-FX is not supported".
> Changes in v6:
> - nothing changed.
> Changes in v5:
> - include Heiner's patch "net: phy: add support for clause 37
> auto-negotiation" into the series.
> - use genphy_c37_config_aneg and genphy_c37_read_status in BCM54616S
> PHY driver's callback when the PHY is running in 1000Base-X mode.
> 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.
>
> drivers/net/phy/broadcom.c | 57 +++++++++++++++++++++++++++++++++++---
> include/linux/brcmphy.h | 10 +++++--
> 2 files changed, 61 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
> index 937d0059e8ac..5fd9293513d8 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]
> @@ -451,12 +451,47 @@ 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-fiber mode when INTERF_SEL[1:0]
> + * is 01b, and the link between PHY and its link partner can be
> + * either 1000Base-X or 100Base-FX.
> + * RGMII-1000Base-X is properly supported, but RGMII-100Base-FX
> + * support is still missing as of now.
> + */
> + 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(struct phy_device *phydev)
> {
> int ret;
>
> /* Aneg firsly. */
> - ret = genphy_config_aneg(phydev);
> + if (phydev->dev_flags & PHY_BCM_FLAGS_MODE_1000BX)
> + ret = genphy_c37_config_aneg(phydev);
> + else
> + ret = genphy_config_aneg(phydev);
>
> /* Then we can set up the delay. */
> bcm54xx_config_clock_delay(phydev);
> @@ -464,6 +499,18 @@ static int bcm54616s_config_aneg(struct phy_device *phydev)
> return ret;
> }
>
> +static int bcm54616s_read_status(struct phy_device *phydev)
> +{
> + int err;
> +
> + if (phydev->dev_flags & PHY_BCM_FLAGS_MODE_1000BX)
> + err = genphy_c37_read_status(phydev);
> + else
> + err = genphy_read_status(phydev);
> +
> + return err;
> +}
> +
> static int brcm_phy_setbits(struct phy_device *phydev, int reg, int set)
> {
> int val;
> @@ -655,6 +702,8 @@ 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 = bcm54616s_read_status,
> + .probe = bcm54616s_probe,
> }, {
> .phy_id = PHY_ID_BCM5464,
> .phy_id_mask = 0xfffffff0,
> diff --git a/include/linux/brcmphy.h b/include/linux/brcmphy.h
> index 6db2d9a6e503..b475e7f20d28 100644
> --- a/include/linux/brcmphy.h
> +++ b/include/linux/brcmphy.h
> @@ -200,9 +200,15 @@
> #define BCM5482_SHD_SSD 0x14 /* 10100: Secondary SerDes control */
> #define BCM5482_SHD_SSD_LEDM 0x0008 /* SSD LED Mode enable */
> #define BCM5482_SHD_SSD_EN 0x0001 /* SSD enable */
> -#define BCM5482_SHD_MODE 0x1f /* 11111: Mode Control Register */
> -#define BCM5482_SHD_MODE_1000BX 0x0001 /* Enable 1000BASE-X registers */
>
> +/* 10011: SerDes 100-FX Control Register */
> +#define BCM54616S_SHD_100FX_CTRL 0x13
> +#define BCM54616S_100FX_MODE BIT(0) /* 100-FX SerDes Enable */
> +
> +/* 11111: Mode Control Register */
> +#define BCM54XX_SHD_MODE 0x1f
> +#define BCM54XX_SHD_INTF_SEL_MASK GENMASK(2, 1) /* INTERF_SEL[1:0] */
> +#define BCM54XX_SHD_MODE_1000BX BIT(0) /* Enable 1000-X registers */
>
> /*
> * EXPANSION SHADOW ACCESS REGISTERS. (PHY REG 0x15, 0x16, and 0x17)
>