Re: [PATCH] net: phy: marvell: clear wol event before setting it

[Bhadram Varka <vbhadram@nvidia.com>]

Hi,

On 4/26/2018 11:56 AM, Bhadram Varka wrote:
> Hi,
> On 4/26/2018 11:45 AM, Jisheng Zhang wrote:
>> Hi,
>>
>> On Thu, 26 Apr 2018 11:10:21 +0530 Bhadram Varka wrote:
>>
>>> Hi,
>>>
>>> On 4/19/2018 5:48 PM, Andrew Lunn wrote:
>>>> On Thu, Apr 19, 2018 at 04:02:32PM +0800, Jisheng Zhang wrote:
>>>>> From: Jingju Hou <Jingju.Hou@synaptics.com>
>>>>>
>>>>> If WOL event happened once, the LED[2] interrupt pin will not be
>>>>> cleared unless reading the CSISR register. So clear the WOL event
>>>>> before enabling it.
>>>>>
>>>>> Signed-off-by: Jingju Hou <Jingju.Hou@synaptics.com>
>>>>> Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
>>>>> ---
>>>>>    drivers/net/phy/marvell.c | 9 +++++++++
>>>>>    1 file changed, 9 insertions(+)
>>>>>
>>>>> diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
>>>>> index c22e8e383247..b6abe1cbc84b 100644
>>>>> --- a/drivers/net/phy/marvell.c
>>>>> +++ b/drivers/net/phy/marvell.c
>>>>> @@ -115,6 +115,9 @@
>>>>>    /* WOL Event Interrupt Enable */
>>>>>    #define MII_88E1318S_PHY_CSIER_WOL_EIE BIT(7)
>>>>>    +/* Copper Specific Interrupt Status Register */
>>>>> +#define MII_88E1318S_PHY_CSISR                0x13
>>>>> +
>>>>>    /* LED Timer Control Register */
>>>>>    #define MII_88E1318S_PHY_LED_TCR            0x12
>>>>>    #define MII_88E1318S_PHY_LED_TCR_FORCE_INT BIT(15)
>>>>> @@ -1393,6 +1396,12 @@ static int m88e1318_set_wol(struct 
>>>>> phy_device *phydev,
>>>>>            if (err < 0)
>>>>>                goto error;
>>>>>    +        /* If WOL event happened once, the LED[2] interrupt pin
>>>>> +         * will not be cleared unless reading the CSISR register.
>>>>> +         * So clear the WOL event first before enabling it.
>>>>> +         */
>>>>> +        phy_read(phydev, MII_88E1318S_PHY_CSISR);
>>>>> +
>>>> Hi Jisheng
>>>>
>>>> The problem with this is, you could be clearing a real interrupt, link
>>>> down/up etc. If interrupts are in use, i think the normal interrupt
>>>> handling will clear the WOL interrupt? So can you make this read
>>>> conditional on !phy_interrupt_is_valid()?
>>> So this will clear WoL interrupt bit from Copper Interrupt status 
>>> register.
>>>
>>> How about clearing WoL status (Page 17, register 17) for every WOL 
>>> event ?
>>>
>> This is already properly done by setting 
>> MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS
>> in m88e1318_set_wol()
> This part of the code executes only when we enable WOL through ethtool 
> (ethtool -s eth0 wol g)
>
> Lets say once WOL enabled through magic packet - HW generates WOL 
> interrupt once magic packet received.
> The problem that I see here is that for the next immediate magic 
> packet I don't see WOL interrupt generated by the HW.
> I need to explicitly clear WOL status for HW to generate WOL interrupt.

With the below patch I see WOL event interrupt for every magic packet 
that HW receives...

diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index ed8a67d..5d3d138 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -55,6 +55,7 @@

  #define MII_M1011_IEVENT               0x13
  #define MII_M1011_IEVENT_CLEAR         0x0000
+#define MII_M1011_IEVENT_WOL_EVENT     BIT(7)

  #define MII_M1011_IMASK                        0x12
- #define MII_M1011_IMASK_INIT           0x6400
+ #define MII_M1011_IMASK_INIT           0x6480

@@ -195,13 +196,40 @@ struct marvell_priv {
         bool copper;
  };

+static int marvell_clear_wol_status(struct phy_device *phydev)
+{
+       int err, temp, oldpage;
+
+       oldpage = phy_read(phydev, MII_MARVELL_PHY_PAGE);
+       if (oldpage < 0)
+               return oldpage;
+
+       err = phy_write(phydev, MII_MARVELL_PHY_PAGE,
+                        MII_88E1318S_PHY_WOL_PAGE);
+       if (err < 0)
+               return err;
+
+       /*
+        * Clear WOL status so that for next WOL event
+        * interrupt will be generated by HW
+        */
+       temp = phy_read(phydev, MII_88E1318S_PHY_WOL_CTRL);
+       temp |= MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS;
+       err = phy_write(phydev, MII_88E1318S_PHY_WOL_CTRL, temp);
+       if (err < 0)
+               return err;
+
+
+       phy_write(phydev, MII_MARVELL_PHY_PAGE, oldpage);
+
+       return 0;
+}
+
  static int marvell_ack_interrupt(struct phy_device *phydev)
  {
         int err;

         /* Clear the interrupts by reading the reg */
         err = phy_read(phydev, MII_M1011_IEVENT);
-
         if (err < 0)
                 return err;

@@ -1454,12 +1482,18 @@ static int marvell_aneg_done(struct phy_device 
*phydev)

  static int m88e1121_did_interrupt(struct phy_device *phydev)
  {
-       int imask;
+       int imask, err;

         imask = phy_read(phydev, MII_M1011_IEVENT);

-       if (imask & MII_M1011_IMASK_INIT)
+       if (imask & MII_M1011_IMASK_INIT) {
+               if (imask & MII_M1011_IEVENT_WOL_EVENT) {
+                       err = marvell_clear_wol_status(phydev);
+                       if (err < 0)
+                               return 0;
+               }
                 return 1;
+       }

         return 0;
  }