| Message ID | 20210122150334.2378703-1-mkl@pengutronix.de (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: dp83tc811: fix link detection and possbile IRQ storm | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Guessing tree name failed - patch did not apply |
On 1/22/21 4:03 PM, Marc Kleine-Budde wrote: > In our setup the dp83tc811 is configure to master mode. When there is no slave > connected the dp83tc811 triggers an interrupt is triggerd, several bits in the > status registers are set, and te INT_N pin goes low. One of interrupt bits is > the NO_FRAME interrupt. > > Reading the status register acknowledges the interrupt, but as there is still > no slave connected, the NO_FRAME interrupt stays set and the INT_N pin low. For > level triggered IRQs this results in an interrupt storm, as long as the slave > is not connected. For edge triggered interupts the link change event, when the > slave comes online, is lost. > > To fix this problem the NO_FRAME interrupt is not enabled. At least in our > testcase with edge triggered interrupts link change events are now properly > detected. > > Cc: Dan Murphy <dmurphy@ti.com> > Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Sorry - this patch will not apply as is, I'll send an updated version. Marc
On Fri, Jan 22, 2021 at 04:03:34PM +0100, Marc Kleine-Budde wrote: > In our setup the dp83tc811 is configure to master mode. When there is no slave > connected the dp83tc811 triggers an interrupt is triggerd, several bits in the > status registers are set, and te INT_N pin goes low. One of interrupt bits is > the NO_FRAME interrupt. > > Reading the status register acknowledges the interrupt, but as there is still > no slave connected, the NO_FRAME interrupt stays set and the INT_N pin low. For > level triggered IRQs this results in an interrupt storm, as long as the slave > is not connected. For edge triggered interupts the link change event, when the > slave comes online, is lost. > > To fix this problem the NO_FRAME interrupt is not enabled. At least in our > testcase with edge triggered interrupts link change events are now properly > detected. > > Cc: Dan Murphy <dmurphy@ti.com> > Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Hi Marc Seems reasonable. Please add to your rebased version: Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/net/phy/dp83tc811.c b/drivers/net/phy/dp83tc811.c index b8d802cbf615..2801492bfaad 100644 --- a/drivers/net/phy/dp83tc811.c +++ b/drivers/net/phy/dp83tc811.c @@ -222,7 +222,6 @@ static int dp83811_config_intr(struct phy_device *phydev) return err; misr_status = (DP83811_LPS_INT_EN | - DP83811_NO_FRAME_INT_EN | DP83811_POR_DONE_INT_EN); err = phy_write(phydev, MII_DP83811_INT_STAT3, misr_status);
In our setup the dp83tc811 is configure to master mode. When there is no slave connected the dp83tc811 triggers an interrupt is triggerd, several bits in the status registers are set, and te INT_N pin goes low. One of interrupt bits is the NO_FRAME interrupt. Reading the status register acknowledges the interrupt, but as there is still no slave connected, the NO_FRAME interrupt stays set and the INT_N pin low. For level triggered IRQs this results in an interrupt storm, as long as the slave is not connected. For edge triggered interupts the link change event, when the slave comes online, is lost. To fix this problem the NO_FRAME interrupt is not enabled. At least in our testcase with edge triggered interrupts link change events are now properly detected. Cc: Dan Murphy <dmurphy@ti.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/phy/dp83tc811.c | 1 - 1 file changed, 1 deletion(-)