On 15.02.2021 17:57, Bjarni Jonasson wrote:
> At Power-On Reset, transients may cause the LCPLL to lock onto a
> clock that is momentarily unstable. This is normally seen in QSGMII
> setups where the higher speed 6G SerDes is being used.
> This patch adds an initial LCPLL Reset to the PHY (first instance)
> to avoid this issue.
>
> Signed-off-by: Steen Hegelund <steen.hegel...@microchip.com>
> Signed-off-by: Bjarni Jonasson <bjarni.jonas...@microchip.com>
> Fixes: e4f9ba642f0b ("net: phy: mscc: add support for VSC8514 PHY.")
Cover letter is missing, and Fixes should be first.
> ---
> v1 -> v2:
> Preserved reversed christmas tree
> Removed forward definitions
> Fixed build issues
> Changed net to net-next
>
> drivers/net/phy/mscc/mscc.h | 8 +
> drivers/net/phy/mscc/mscc_main.c | 354 ++++++++++++++++++++-----------
> 2 files changed, 240 insertions(+), 122 deletions(-)
>
> diff --git a/drivers/net/phy/mscc/mscc.h b/drivers/net/phy/mscc/mscc.h
> index 9481bce94c2e..c2023f93c0b2 100644
> --- a/drivers/net/phy/mscc/mscc.h
> +++ b/drivers/net/phy/mscc/mscc.h
> @@ -102,6 +102,7 @@ enum rgmii_clock_delay {
> #define PHY_MCB_S6G_READ BIT(30)
>
> #define PHY_S6G_PLL5G_CFG0 0x06
> +#define PHY_S6G_PLL5G_CFG2 0x08
> #define PHY_S6G_LCPLL_CFG 0x11
> #define PHY_S6G_PLL_CFG 0x2b
> #define PHY_S6G_COMMON_CFG 0x2c
> @@ -121,6 +122,9 @@ enum rgmii_clock_delay {
> #define PHY_S6G_PLL_FSM_CTRL_DATA_POS 8
> #define PHY_S6G_PLL_FSM_ENA_POS 7
>
> +#define PHY_S6G_CFG2_FSM_DIS 1
> +#define PHY_S6G_CFG2_FSM_CLK_BP 23
> +
> #define MSCC_EXT_PAGE_ACCESS 31
> #define MSCC_PHY_PAGE_STANDARD 0x0000 /* Standard registers
> */
> #define MSCC_PHY_PAGE_EXTENDED 0x0001 /* Extended registers
> */
> @@ -412,6 +416,10 @@ struct vsc8531_edge_rate_table {
> };
> #endif /* CONFIG_OF_MDIO */
>
> +enum csr_target {
> + MACRO_CTRL = 0x07,
> +};
> +
> #if IS_ENABLED(CONFIG_MACSEC)
> int vsc8584_macsec_init(struct phy_device *phydev);
> void vsc8584_handle_macsec_interrupt(struct phy_device *phydev);
> diff --git a/drivers/net/phy/mscc/mscc_main.c
> b/drivers/net/phy/mscc/mscc_main.c
> index 2f2157e3deab..09650c3340a1 100644
> --- a/drivers/net/phy/mscc/mscc_main.c
> +++ b/drivers/net/phy/mscc/mscc_main.c
> @@ -710,6 +710,113 @@ static int phy_base_read(struct phy_device *phydev, u32
> regnum)
> return __phy_package_read(phydev, regnum);
> }
>
> +static u32 vsc85xx_csr_read(struct phy_device *phydev,
> + enum csr_target target, u32 reg)
> +{
> + unsigned long deadline;
> + u32 val, val_l, val_h;
> +
> + phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS, MSCC_PHY_PAGE_CSR_CNTL);
> +
> + /* CSR registers are grouped under different Target IDs.
> + * 6-bit Target_ID is split between MSCC_EXT_PAGE_CSR_CNTL_20 and
> + * MSCC_EXT_PAGE_CSR_CNTL_19 registers.
> + * Target_ID[5:2] maps to bits[3:0] of MSCC_EXT_PAGE_CSR_CNTL_20
> + * and Target_ID[1:0] maps to bits[13:12] of MSCC_EXT_PAGE_CSR_CNTL_19.
> + */
> +
> + /* Setup the Target ID */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_20,
> + MSCC_PHY_CSR_CNTL_20_TARGET(target >> 2));
> +
> + if ((target >> 2 == 0x1) || (target >> 2 == 0x3))
> + /* non-MACsec access */
> + target &= 0x3;
> + else
> + target = 0;
> +
> + /* Trigger CSR Action - Read into the CSR's */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_19,
> + MSCC_PHY_CSR_CNTL_19_CMD | MSCC_PHY_CSR_CNTL_19_READ |
> + MSCC_PHY_CSR_CNTL_19_REG_ADDR(reg) |
> + MSCC_PHY_CSR_CNTL_19_TARGET(target));
> +
> + /* Wait for register access*/
> + deadline = jiffies + msecs_to_jiffies(PROC_CMD_NCOMPLETED_TIMEOUT_MS);
> + do {
> + usleep_range(500, 1000);
> + val = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_19);
> + } while (time_before(jiffies, deadline) &&
> + !(val & MSCC_PHY_CSR_CNTL_19_CMD));
> +
> + if (!(val & MSCC_PHY_CSR_CNTL_19_CMD))
> + return 0xffffffff;
> +
> + /* Read the Least Significant Word (LSW) (17) */
> + val_l = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_17);
> +
> + /* Read the Most Significant Word (MSW) (18) */
> + val_h = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_18);
> +
> + phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS,
> + MSCC_PHY_PAGE_STANDARD);
> +
> + return (val_h << 16) | val_l;
> +}
> +
> +static int vsc85xx_csr_write(struct phy_device *phydev,
> + enum csr_target target, u32 reg, u32 val)
> +{
> + unsigned long deadline;
> +
> + phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS, MSCC_PHY_PAGE_CSR_CNTL);
> +
> + /* CSR registers are grouped under different Target IDs.
> + * 6-bit Target_ID is split between MSCC_EXT_PAGE_CSR_CNTL_20 and
> + * MSCC_EXT_PAGE_CSR_CNTL_19 registers.
> + * Target_ID[5:2] maps to bits[3:0] of MSCC_EXT_PAGE_CSR_CNTL_20
> + * and Target_ID[1:0] maps to bits[13:12] of MSCC_EXT_PAGE_CSR_CNTL_19.
> + */
> +
> + /* Setup the Target ID */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_20,
> + MSCC_PHY_CSR_CNTL_20_TARGET(target >> 2));
> +
> + /* Write the Least Significant Word (LSW) (17) */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_17, (u16)val);
> +
> + /* Write the Most Significant Word (MSW) (18) */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_18, (u16)(val >> 16));
> +
> + if ((target >> 2 == 0x1) || (target >> 2 == 0x3))
> + /* non-MACsec access */
> + target &= 0x3;
> + else
> + target = 0;
> +
> + /* Trigger CSR Action - Write into the CSR's */
> + phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_19,
> + MSCC_PHY_CSR_CNTL_19_CMD |
> + MSCC_PHY_CSR_CNTL_19_REG_ADDR(reg) |
> + MSCC_PHY_CSR_CNTL_19_TARGET(target));
> +
> + /* Wait for register access */
> + deadline = jiffies + msecs_to_jiffies(PROC_CMD_NCOMPLETED_TIMEOUT_MS);
> + do {
> + usleep_range(500, 1000);
> + val = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_19);
> + } while (time_before(jiffies, deadline) &&
> + !(val & MSCC_PHY_CSR_CNTL_19_CMD));
> +
> + if (!(val & MSCC_PHY_CSR_CNTL_19_CMD))
> + return -ETIMEDOUT;
> +
> + phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS,
> + MSCC_PHY_PAGE_STANDARD);
> +
> + return 0;
> +}
> +
> /* bus->mdio_lock should be locked when using this function */
> static void vsc8584_csr_write(struct phy_device *phydev, u16 addr, u32 val)
> {
> @@ -1131,6 +1238,96 @@ static int vsc8574_config_pre_init(struct phy_device
> *phydev)
> return ret;
> }
>
> +/* Access LCPLL Cfg_2 */
> +static void vsc8584_pll5g_cfg2_wr(struct phy_device *phydev,
> + bool disable_fsm, bool ena_clk_bypass)
Both callers use ena_clk_bypass = 0, do you plan to add further users?
Else the parameter could be removed.
> +{
> + u32 rd_dat;
> +
> + rd_dat = vsc85xx_csr_read(phydev, MACRO_CTRL, PHY_S6G_PLL5G_CFG2);
> + rd_dat &= ~(BIT(PHY_S6G_CFG2_FSM_CLK_BP) | BIT(PHY_S6G_CFG2_FSM_DIS));
> + rd_dat |= (disable_fsm << PHY_S6G_CFG2_FSM_DIS) |
> + (ena_clk_bypass << PHY_S6G_CFG2_FSM_CLK_BP);
> + vsc85xx_csr_write(phydev, MACRO_CTRL, PHY_S6G_PLL5G_CFG2, rd_dat);
> +}
> +
> +/* trigger a read to the spcified MCB */
> +static int vsc8584_mcb_rd_trig(struct phy_device *phydev,
> + u32 mcb_reg_addr, u8 mcb_slave_num)
> +{
> + u32 rd_dat = 0;
> +
> + /* read MCB */
> + vsc85xx_csr_write(phydev, MACRO_CTRL, mcb_reg_addr,
> + (0x40000000 | (1L << mcb_slave_num)));
> +
> + return read_poll_timeout(vsc85xx_csr_read, rd_dat,
> + !(rd_dat & 0x40000000),
> + 4000, 200000, 0,
> + phydev, MACRO_CTRL, mcb_reg_addr);
> +}
> +
> +/* trigger a write to the spcified MCB */
> +static int vsc8584_mcb_wr_trig(struct phy_device *phydev,
> + u32 mcb_reg_addr,
> + u8 mcb_slave_num)
> +{
> + u32 rd_dat = 0;
> +
> + /* write back MCB */
> + vsc85xx_csr_write(phydev, MACRO_CTRL, mcb_reg_addr,
> + (0x80000000 | (1L << mcb_slave_num)));
> +
> + return read_poll_timeout(vsc85xx_csr_read, rd_dat,
> + !(rd_dat & 0x80000000),
> + 4000, 200000, 0,
> + phydev, MACRO_CTRL, mcb_reg_addr);
> +}
> +
> +/* Sequence to Reset LCPLL for the VIPER and ELISE PHY */
> +static int vsc8584_pll5g_reset(struct phy_device *phydev)
> +{
> + bool ena_clk_bypass;
> + bool dis_fsm;
> + int ret = 0;
> +
> + ret = vsc8584_mcb_rd_trig(phydev, 0x11, 0);
> + if (ret < 0)
> + goto done;
> + dis_fsm = 1;
> + ena_clk_bypass = 0;
> +
> + /* Reset LCPLL */
> + vsc8584_pll5g_cfg2_wr(phydev, dis_fsm, ena_clk_bypass);
> +
> + /* write back LCPLL MCB */
> + ret = vsc8584_mcb_wr_trig(phydev, 0x11, 0);
> + if (ret < 0)
> + goto done;
> +
> + /* 10 mSec sleep while LCPLL is hold in reset */
> + usleep_range(10000, 20000);
> +
> + /* read LCPLL MCB into CSRs */
> + ret = vsc8584_mcb_rd_trig(phydev, 0x11, 0);
> + if (ret < 0)
> + goto done;
> + dis_fsm = 0;
> + ena_clk_bypass = 0;
> +
> + /* Release the Reset of LCPLL */
> + vsc8584_pll5g_cfg2_wr(phydev, dis_fsm, ena_clk_bypass);
> +
> + /* write back LCPLL MCB */
> + ret = vsc8584_mcb_wr_trig(phydev, 0x11, 0);
> + if (ret < 0)
> + goto done;
> +
> + usleep_range(110000, 200000);
> +done:
> + return ret;
> +}
> +
> /* bus->mdio_lock should be locked when using this function */
> static int vsc8584_config_pre_init(struct phy_device *phydev)
> {
> @@ -1569,8 +1766,16 @@ static int vsc8514_config_pre_init(struct phy_device
> *phydev)
> {0x16b2, 0x00007000},
> {0x16b4, 0x00000814},
> };
> + struct device *dev = &phydev->mdio.dev;
> unsigned int i;
> u16 reg;
> + int ret;
> +
> + ret = vsc8584_pll5g_reset(phydev);
> + if (ret < 0) {
> + dev_err(dev, "failed LCPLL reset, ret: %d\n", ret);
> + return ret;
> + }
>
> phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS, MSCC_PHY_PAGE_STANDARD);
>
> @@ -1605,101 +1810,6 @@ static int vsc8514_config_pre_init(struct phy_device
> *phydev)
> return 0;
> }
>
> -static u32 vsc85xx_csr_ctrl_phy_read(struct phy_device *phydev,
> - u32 target, u32 reg)
> -{
> - unsigned long deadline;
> - u32 val, val_l, val_h;
> -
> - phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS, MSCC_PHY_PAGE_CSR_CNTL);
> -
> - /* CSR registers are grouped under different Target IDs.
> - * 6-bit Target_ID is split between MSCC_EXT_PAGE_CSR_CNTL_20 and
> - * MSCC_EXT_PAGE_CSR_CNTL_19 registers.
> - * Target_ID[5:2] maps to bits[3:0] of MSCC_EXT_PAGE_CSR_CNTL_20
> - * and Target_ID[1:0] maps to bits[13:12] of MSCC_EXT_PAGE_CSR_CNTL_19.
> - */
> -
> - /* Setup the Target ID */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_20,
> - MSCC_PHY_CSR_CNTL_20_TARGET(target >> 2));
> -
> - /* Trigger CSR Action - Read into the CSR's */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_19,
> - MSCC_PHY_CSR_CNTL_19_CMD | MSCC_PHY_CSR_CNTL_19_READ |
> - MSCC_PHY_CSR_CNTL_19_REG_ADDR(reg) |
> - MSCC_PHY_CSR_CNTL_19_TARGET(target & 0x3));
> -
> - /* Wait for register access*/
> - deadline = jiffies + msecs_to_jiffies(PROC_CMD_NCOMPLETED_TIMEOUT_MS);
> - do {
> - usleep_range(500, 1000);
> - val = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_19);
> - } while (time_before(jiffies, deadline) &&
> - !(val & MSCC_PHY_CSR_CNTL_19_CMD));
> -
> - if (!(val & MSCC_PHY_CSR_CNTL_19_CMD))
> - return 0xffffffff;
> -
> - /* Read the Least Significant Word (LSW) (17) */
> - val_l = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_17);
> -
> - /* Read the Most Significant Word (MSW) (18) */
> - val_h = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_18);
> -
> - phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS,
> - MSCC_PHY_PAGE_STANDARD);
> -
> - return (val_h << 16) | val_l;
> -}
> -
> -static int vsc85xx_csr_ctrl_phy_write(struct phy_device *phydev,
> - u32 target, u32 reg, u32 val)
> -{
> - unsigned long deadline;
> -
> - phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS, MSCC_PHY_PAGE_CSR_CNTL);
> -
> - /* CSR registers are grouped under different Target IDs.
> - * 6-bit Target_ID is split between MSCC_EXT_PAGE_CSR_CNTL_20 and
> - * MSCC_EXT_PAGE_CSR_CNTL_19 registers.
> - * Target_ID[5:2] maps to bits[3:0] of MSCC_EXT_PAGE_CSR_CNTL_20
> - * and Target_ID[1:0] maps to bits[13:12] of MSCC_EXT_PAGE_CSR_CNTL_19.
> - */
> -
> - /* Setup the Target ID */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_20,
> - MSCC_PHY_CSR_CNTL_20_TARGET(target >> 2));
> -
> - /* Write the Least Significant Word (LSW) (17) */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_17, (u16)val);
> -
> - /* Write the Most Significant Word (MSW) (18) */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_18, (u16)(val >> 16));
> -
> - /* Trigger CSR Action - Write into the CSR's */
> - phy_base_write(phydev, MSCC_EXT_PAGE_CSR_CNTL_19,
> - MSCC_PHY_CSR_CNTL_19_CMD |
> - MSCC_PHY_CSR_CNTL_19_REG_ADDR(reg) |
> - MSCC_PHY_CSR_CNTL_19_TARGET(target & 0x3));
> -
> - /* Wait for register access */
> - deadline = jiffies + msecs_to_jiffies(PROC_CMD_NCOMPLETED_TIMEOUT_MS);
> - do {
> - usleep_range(500, 1000);
> - val = phy_base_read(phydev, MSCC_EXT_PAGE_CSR_CNTL_19);
> - } while (time_before(jiffies, deadline) &&
> - !(val & MSCC_PHY_CSR_CNTL_19_CMD));
> -
> - if (!(val & MSCC_PHY_CSR_CNTL_19_CMD))
> - return -ETIMEDOUT;
> -
> - phy_base_write(phydev, MSCC_EXT_PAGE_ACCESS,
> - MSCC_PHY_PAGE_STANDARD);
> -
> - return 0;
> -}
> -
> static int __phy_write_mcb_s6g(struct phy_device *phydev, u32 reg, u8 mcb,
> u32 op)
> {
> @@ -1707,15 +1817,15 @@ static int __phy_write_mcb_s6g(struct phy_device
> *phydev, u32 reg, u8 mcb,
> u32 val;
> int ret;
>
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET, reg,
> - op | (1 << mcb));
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET, reg,
> + op | (1 << mcb));
> if (ret)
> return -EINVAL;
>
> deadline = jiffies + msecs_to_jiffies(PROC_CMD_NCOMPLETED_TIMEOUT_MS);
> do {
> usleep_range(500, 1000);
> - val = vsc85xx_csr_ctrl_phy_read(phydev, PHY_MCB_TARGET, reg);
> + val = vsc85xx_csr_read(phydev, PHY_MCB_TARGET, reg);
>
> if (val == 0xffffffff)
> return -EIO;
> @@ -1796,41 +1906,41 @@ static int vsc8514_config_init(struct phy_device
> *phydev)
> /* lcpll mcb */
> phy_update_mcb_s6g(phydev, PHY_S6G_LCPLL_CFG, 0);
> /* pll5gcfg0 */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_PLL5G_CFG0, 0x7036f145);
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_PLL5G_CFG0, 0x7036f145);
> if (ret)
> goto err;
>
> phy_commit_mcb_s6g(phydev, PHY_S6G_LCPLL_CFG, 0);
> /* pllcfg */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_PLL_CFG,
> - (3 << PHY_S6G_PLL_ENA_OFFS_POS) |
> - (120 << PHY_S6G_PLL_FSM_CTRL_DATA_POS)
> - | (0 << PHY_S6G_PLL_FSM_ENA_POS));
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_PLL_CFG,
> + (3 << PHY_S6G_PLL_ENA_OFFS_POS) |
> + (120 << PHY_S6G_PLL_FSM_CTRL_DATA_POS)
> + | (0 << PHY_S6G_PLL_FSM_ENA_POS));
> if (ret)
> goto err;
>
> /* commoncfg */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_COMMON_CFG,
> - (0 << PHY_S6G_SYS_RST_POS) |
> - (0 << PHY_S6G_ENA_LANE_POS) |
> - (0 << PHY_S6G_ENA_LOOP_POS) |
> - (0 << PHY_S6G_QRATE_POS) |
> - (3 << PHY_S6G_IF_MODE_POS));
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_COMMON_CFG,
> + (0 << PHY_S6G_SYS_RST_POS) |
> + (0 << PHY_S6G_ENA_LANE_POS) |
> + (0 << PHY_S6G_ENA_LOOP_POS) |
> + (0 << PHY_S6G_QRATE_POS) |
> + (3 << PHY_S6G_IF_MODE_POS));
> if (ret)
> goto err;
>
> /* misccfg */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_MISC_CFG, 1);
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_MISC_CFG, 1);
> if (ret)
> goto err;
>
> /* gpcfg */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_GPC_CFG, 768);
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_GPC_CFG, 768);
> if (ret)
> goto err;
>
> @@ -1841,8 +1951,8 @@ static int vsc8514_config_init(struct phy_device
> *phydev)
> usleep_range(500, 1000);
> phy_update_mcb_s6g(phydev, PHY_MCB_S6G_CFG,
> 0); /* read 6G MCB into CSRs */
> - reg = vsc85xx_csr_ctrl_phy_read(phydev, PHY_MCB_TARGET,
> - PHY_S6G_PLL_STATUS);
> + reg = vsc85xx_csr_read(phydev, PHY_MCB_TARGET,
> + PHY_S6G_PLL_STATUS);
> if (reg == 0xffffffff) {
> phy_unlock_mdio_bus(phydev);
> return -EIO;
> @@ -1856,8 +1966,8 @@ static int vsc8514_config_init(struct phy_device
> *phydev)
> }
>
> /* misccfg */
> - ret = vsc85xx_csr_ctrl_phy_write(phydev, PHY_MCB_TARGET,
> - PHY_S6G_MISC_CFG, 0);
> + ret = vsc85xx_csr_write(phydev, PHY_MCB_TARGET,
> + PHY_S6G_MISC_CFG, 0);
> if (ret)
> goto err;
>
> @@ -1868,8 +1978,8 @@ static int vsc8514_config_init(struct phy_device
> *phydev)
> usleep_range(500, 1000);
> phy_update_mcb_s6g(phydev, PHY_MCB_S6G_CFG,
> 0); /* read 6G MCB into CSRs */
> - reg = vsc85xx_csr_ctrl_phy_read(phydev, PHY_MCB_TARGET,
> - PHY_S6G_IB_STATUS0);
> + reg = vsc85xx_csr_read(phydev, PHY_MCB_TARGET,
> + PHY_S6G_IB_STATUS0);
> if (reg == 0xffffffff) {
> phy_unlock_mdio_bus(phydev);
> return -EIO;
>
