Re: pch_can: Data transmission stops after dropped packet

[Wolfgang Grandegger <wg@grandegger.com>]

On 11/21/2012 03:52 PM, Michael Pellegrini wrote:
> Wolfgang Grandegger <wg <at> grandegger.com> writes:
> 
>> I'm a bit confused. Where is the application running? On this
>> PCH-System? Or does an external node send messages, which are not
>> received by the PCH-C_CAN?
> 
> The application is running on the PCH-System.  Here are the systems on the bus:
> 
> - PCH-System: Runs the application which sends the majority of CAN messages.
> - External Node: Sends periodic CAN messages.
> - CAN Monitor: Monitors all bus traffic.
> 
> The PCH-System sends 16 CAN messages successfully before transmission stops.
> The CAN Monitor system successfully receives these messages.
> As shown by the "ip" command output, the driver considers these messages
> dropped, not transmitted.
> The External Node system sends periodic messages, which I can see on the CAN
> Monitor system.  The PCH-System does not receive these messages.
> 
>> OK, we still have a problem with TX and RX, most likely with interrupts.
>> Could you please send a message on the PCH-System executing
>> "cansend can0 123#abcdef":
>>
>> - Does "candump any,0:0,#FFFFFFFF" report anything.
> 
> No, candump reports nothing.

OK, normally you should see here the loopback of the transmitted
messages. But the loopback does not happen because the TX done interrupt
does not occur.

> 
>> - Does the message show up on the bus (visiable to another node or
>>   analyser)?
> 
> Yes, the message shows up on the bus.  The CAN Monitor system receives
> the message.

OK.

>> - Does the interrupt count increase? Check output of /proc/interrupts.
> 
> I'm not sure exactly which piece of data you're looking for, so here's
> the entirety of /proc/interrupts:
> 
>            CPU0       CPU1
>   0:   68369230          0   IO-APIC-edge      timer
>   8:          1          0   IO-APIC-edge      rtc0
>   9:          0          0   IO-APIC-fasteoi   acpi
>  16:      27694          0   IO-APIC-fasteoi   PCIe PME, PCIe PME, PCIe PME, PCI
> e PME, ehci_hcd:usb2, ohci_hcd:usb6, ohci_hcd:usb7, ohci_hcd:usb8, gpio_pch, snd
> _hda_intel
>  18:          0          0   IO-APIC-fasteoi   mmc0, mmc1
>  19:      22916          0   IO-APIC-fasteoi   ehci_hcd:usb1, ohci_hcd:usb3, ohc
> i_hcd:usb4, ohci_hcd:usb5
>  40:      83612          0   PCI-MSI-edge      ahci
>  41:          0          0   PCI-MSI-edge      can0

We do *not* yet get any interrupt and that's why TX and RX does not yet
work.

> Note that this test was run with v3 of the driver.

Ok, could you please try v4. Thanks.

Wolfgang.