Subject: Re: [PATCHv3 (net.git) 2/2] stmmac: fix MDIO settings

From: Phil Reid <[email-masked]>
Date: Mon, 14 Mar 2016 08:50:37 +0800

G'day Giuseppe,

On 11/03/2016 11:32 PM, Giuseppe CAVALLARO wrote:
> On 3/11/2016 4:14 PM, Phil Reid wrote:
>> G'day Giuseppe,
>>
>> I wont be able to test until Monday.
>> Concept looks ok to me except for comment below.
>>
>> On 11/03/2016 9:33 PM, Giuseppe Cavallaro wrote:
>>> Initially the phy_bus_name was added to manipulate the
>>> driver name but It was recently just used to manage the
>>> fixed-link and then to take some decision at run-time
>>> inside the main (for example to skip EEE).
>>> So the patch uses the is_pseudo_fixed_link and removes
>>> removes the phy_bus_name variable not necessary anymore.
>>>
>>> The driver can manage the mdio registration by using phy-handle,
>>> dwmac-mdio and own parameter e.g. snps,phy-addr.
>>> This patch takes care about all these possible configurations
>>> and fixes the mdio registration in case of there is a real
>>> transceiver or a switch (that needs to be managed by using
>>> fixed-link).
>>>
>>> Signed-off-by: Giuseppe Cavallaro <[email-masked]>
>>> Reviewed-by: Andreas Färber <[email-masked]>
>>> Tested-by: Frank Schäfer <[email-masked]>
>>> Cc: Gabriel Fernandez <[email-masked]>
>>> Cc: Dinh Nguyen <[email-masked]>
>>> Cc: David S. Miller <[email-masked]>
>>> Cc: Phil Reid <[email-masked]>
>>> ---
>>>
>>> V2: use is_pseudo_fixed_link
>>> V3: parse device-tree driver parameters to allocate PHY resources
>>> considering
>>>      DSA case (+ fixed-link).
>>>
>>>   drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  |   11 +--
>>>   drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c  |   19 +-----
>>>   .../net/ethernet/stmicro/stmmac/stmmac_platform.c  |   77
>>> ++++++++++++++++----
>>>   include/linux/stmmac.h                             |    2 +-
>>>   4 files changed, 68 insertions(+), 41 deletions(-)
>>>
>>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> index c21015b..389d7d0 100644
>>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> @@ -271,7 +271,6 @@ static void stmmac_eee_ctrl_timer(unsigned long arg)
>>>    */
>>>   bool stmmac_eee_init(struct stmmac_priv *priv)
>>>   {
>>> -    char *phy_bus_name = priv->plat->phy_bus_name;
>>>       unsigned long flags;
>>>       bool ret = false;
>>>
>>> @@ -283,7 +282,7 @@ bool stmmac_eee_init(struct stmmac_priv *priv)
>>>           goto out;
>>>
>>>       /* Never init EEE in case of a switch is attached */
>>> -    if (phy_bus_name && (!strcmp(phy_bus_name, "fixed")))
>>> +    if (priv->phydev->is_pseudo_fixed_link)
>>>           goto out;
>>>
>>>       /* MAC core supports the EEE feature. */
>>> @@ -820,12 +819,8 @@ static int stmmac_init_phy(struct net_device *dev)
>>>           phydev = of_phy_connect(dev, priv->plat->phy_node,
>>>                       &stmmac_adjust_link, 0, interface);
>>>       } else {
>>> -        if (priv->plat->phy_bus_name)
>>> -            snprintf(bus_id, MII_BUS_ID_SIZE, "%s-%x",
>>> -                 priv->plat->phy_bus_name, priv->plat->bus_id);
>>> -        else
>>> -            snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x",
>>> -                 priv->plat->bus_id);
>>> +        snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x",
>>> +             priv->plat->bus_id);
>>>
>>>           snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, bus_id,
>>>                priv->plat->phy_addr);
>>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
>>> b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
>>> index 0faf163..3f5512f 100644
>>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
>>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
>>> @@ -198,29 +198,12 @@ int stmmac_mdio_register(struct net_device *ndev)
>>>       struct mii_bus *new_bus;
>>>       struct stmmac_priv *priv = netdev_priv(ndev);
>>>       struct stmmac_mdio_bus_data *mdio_bus_data =
>>> priv->plat->mdio_bus_data;
>>> +    struct device_node *mdio_node = priv->plat->mdio_node;
>>>       int addr, found;
>>> -    struct device_node *mdio_node = NULL;
>>> -    struct device_node *child_node = NULL;
>>>
>>>       if (!mdio_bus_data)
>>>           return 0;
>>>
>>> -    if (IS_ENABLED(CONFIG_OF)) {
>>> -        for_each_child_of_node(priv->device->of_node, child_node) {
>>> -            if (of_device_is_compatible(child_node,
>>> -                            "snps,dwmac-mdio")) {
>>> -                mdio_node = child_node;
>>> -                break;
>>> -            }
>>> -        }
>>> -
>>> -        if (mdio_node) {
>>> -            netdev_dbg(ndev, "FOUND MDIO subnode\n");
>>> -        } else {
>>> -            netdev_warn(ndev, "No MDIO subnode found\n");
>>> -        }
>>> -    }
>>> -
>>>       new_bus = mdiobus_alloc();
>>>       if (new_bus == NULL)
>>>           return -ENOMEM;
>>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>>> b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>>> index 6a52fa1..d2322e9 100644
>>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>>> @@ -96,6 +96,66 @@ static int dwmac1000_validate_ucast_entries(int
>>> ucast_entries)
>>>   }
>>>
>>>   /**
>>> + * stmmac_dt_phy - parse device-tree driver parameters to allocate
>>> PHY resources
>>> + * @plat: driver data platform structure
>>> + * @np: device tree node
>>> + * @dev: device pointer
>>> + * Description:
>>> + * The mdio bus will be allocated in case of a phy transceiver is on
>>> board;
>>> + * it will be NULL if the fixed-link is configured.
>>> + * If there is the "snps,dwmac-mdio" sub-node the mdio will be allocated
>>> + * in any case (for DSA, mdio must be registered even if fixed-link).
>>> + * The table below sums the supported configurations:
>>> + *    -------------------------------
>>> + *    snps,phy-addr    |     Y
>>> + *    -------------------------------
>>> + *    phy-handle    |     Y
>>> + *    -------------------------------
>>> + *    fixed-link    |     N
>>> + *    -------------------------------
>>> + *    snps,dwmac-mdio    |
>>> + *      even if    |     Y
>>> + *    fixed-link    |
>>> + *    -------------------------------
>>> + *
>>> + * It returns true in case of the mdio needs to be registered in the
>>> main.
>>> + */
>>> +static bool stmmac_dt_phy(struct plat_stmmacenet_data *plat,
>>> +              struct device_node *np, struct device *dev)
>>> +{
>>> +    bool ret = true;
>>> +
>>> +    /* If phy-handle property is passed from DT, use it as the PHY */
>>> +    plat->phy_node = of_parse_phandle(np, "phy-handle", 0);
>>> +    if (plat->phy_node)
>>> +        dev_dbg(dev, "Found phy-handle subnode\n");
>>> +
>>> +    /* If phy-handle is not specified, check if we have a fixed-phy */
>>> +    if (!plat->phy_node && of_phy_is_fixed_link(np)) {
>>> +        if ((of_phy_register_fixed_link(np) < 0))
>>> +            return -ENODEV;
>>> +
>>> +        dev_dbg(dev, "Found fixed-link subnode\n");
>>> +        plat->phy_node = of_node_get(np);
>>> +
>>> +        ret = false;
>>> +    }
>>> +
>>> +    /* If snps,dwmac-mdio is passed from DT, always register the MDIO */
>>> +    for_each_child_of_node(np, plat->mdio_node) {
>>> +        if (of_device_is_compatible(plat->mdio_node, "snps,dwmac-mdio"))
>>> +            break;
>>> +    }
>>> +
>>
>> Won't this always result in plat->mdio_node being assigned to something
>> if np has a child.
>> Regardless of the compatible string.
>> Which is why I had the child_node temp.
>> Still learning so may be missing something.
>
> hmm, i think so, let me know as soon as you test it so I can
> rework the patch and send a v4.
>

Tested-by: Phil Reid <[email-masked]>

Ignore my comment above. This works fine.
Test with / without compatible flag and it works as expected.

At the end of the loop for_each_child_of_node sets the node to NULL.

>
>>
>>> +    if (plat->mdio_node) {
>>> +        dev_dbg(dev, "Found MDIO subnode\n");
>>> +        ret = true;
>>> +    }
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +/**
>>>    * stmmac_probe_config_dt - parse device-tree driver parameters
>>>    * @pdev: platform_device structure
>>>    * @plat: driver data platform structure
>>> @@ -129,30 +189,19 @@ stmmac_probe_config_dt(struct platform_device
>>> *pdev, const char **mac)
>>>       /* Default to phy auto-detection */
>>>       plat->phy_addr = -1;
>>>
>>> -    /* If we find a phy-handle property, use it as the PHY */
>>> -    plat->phy_node = of_parse_phandle(np, "phy-handle", 0);
>>> -
>>> -    /* If phy-handle is not specified, check if we have a fixed-phy */
>>> -    if (!plat->phy_node && of_phy_is_fixed_link(np)) {
>>> -        if ((of_phy_register_fixed_link(np) < 0))
>>> -            return ERR_PTR(-ENODEV);
>>> -
>>> -        plat->phy_node = of_node_get(np);
>>> -    }
>>> -
>>>       /* "snps,phy-addr" is not a standard property. Mark it as
>>> deprecated
>>>        * and warn of its use. Remove this when phy node support is added.
>>>        */
>>>       if (of_property_read_u32(np, "snps,phy-addr", &plat->phy_addr)
>>> == 0)
>>>           dev_warn(&pdev->dev, "snps,phy-addr property is deprecated\n");
>>>
>>> -    if ((plat->phy_node && !of_phy_is_fixed_link(np)) ||
>>> plat->phy_bus_name)
>>> -        plat->mdio_bus_data = NULL;
>>> -    else
>>> +    /* To Configure PHY by using all device-tree supported properties */
>>> +    if (stmmac_dt_phy(plat, np, &pdev->dev)) {
>>>           plat->mdio_bus_data =
>>>               devm_kzalloc(&pdev->dev,
>>>                        sizeof(struct stmmac_mdio_bus_data),
>>>                        GFP_KERNEL);
>>> +    }
>>>
>>>       of_property_read_u32(np, "tx-fifo-depth", &plat->tx_fifo_size);
>>>
>>> diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
>>> index eead8ab..8b1ff2b 100644
>>> --- a/include/linux/stmmac.h
>>> +++ b/include/linux/stmmac.h
>>> @@ -94,12 +94,12 @@ struct stmmac_dma_cfg {
>>>   };
>>>
>>>   struct plat_stmmacenet_data {
>>> -    char *phy_bus_name;
>>>       int bus_id;
>>>       int phy_addr;
>>>       int interface;
>>>       struct stmmac_mdio_bus_data *mdio_bus_data;
>>>       struct device_node *phy_node;
>>> +    struct device_node *mdio_node;
>>>       struct stmmac_dma_cfg *dma_cfg;
>>>       int clk_csr;
>>>       int has_gmac;
>>>
>>
>>
>
>
>

-- 
Regards
Phil Reid