On 04/11/2013 09:39 AM, Mylene Josserand wrote:
> Hi Marc,
> 
> Le 10/04/2013 17:30, Marc Kleine-Budde a écrit :
>> On 04/10/2013 04:11 PM, Mylene Josserand wrote:
>>
>>>> If it's the first spi transfer in the driver that hangs and if the
>>>> mcp251x works if loaded as a module, there is probably some
>>>> initialisation missing. Look for stuff that gets initialized after the
>>>> mcp251x would have been loaded if compiled into the kernel. Make a
>>>> "diff" between the bootload with mcp251x compiled into the kernel and
>>>> without. Other usual suspects are: clocks, pinmux (spi _and_ the mcp251x
>>>> dedicated IRQ line), gpio setup.
>>>
>>> Thanks for the advice and the ideas to look at ! I have already compared
>>> the bootload and I have seen no differences (maybe I will check that
>>> another time). I will search about clocks, pinmux and gpio setup and I
>>> will update you if I found how to fix that.
>>
>> Save the bootlog of a system start with the driver compiled as a module
>> into file bootlog-module.txt. Make a second bootlog with the driver
>> compiled into the kernel, save as bootlog-builtin.txt. Then:
>>
>>      diff -u bootlog-module.txt bootlog-builtin.txt
>>
>> Look for the stuff that would have been initialized _after_ the system
>> hangs. The diff should show you this.
>>
>> Marc
>>
> 
> Thank you for the help.
> I have done it and instead of having the mcp configuration, in the 
> bootlog-module, there is the libphy fec_net_mii_bus driver probed and 
> other boot configurations.
> 
> "
>   spi_imx imx27-cspi.0: master is unqueued, this is deprecated
>   spi_imx imx27-cspi.0: probed
>   CAN device driver interface
> -mcp251x_can_init
> -mcp251x_clean
> -mcp251x_can_probe
> -mcp251x_hw_probe
> -mcp251x_hw_reset
> -mcp251x_hw_reset : spi_write : start
> +libphy: fec_enet_mii_bus: probed
> +PPP generic driver version 2.4.2
> +PPP BSD Compression module registered
> +PPP Deflate Compression module registered
> +PPP MPPE Compression module registered
> +ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
> +ehci-mxc: Freescale On-Chip EHCI Host driver
> +mxc-ehci mxc-ehci.2: initializing i.MX USB Controller
> [...]
> "
> 
> If the MCP 251x is compiled as module, will it use the init configuration ?
> 
> I think I have a problem with the irq because I have tried to use it as 
> module and when I do "ifconfig can0 up", I get :
> "
> root@navocap:~# ifconfig can0 up
> genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq 201
> mcp251x spi0.0: failed to acquire irq 201

It's a bug in the driver....which was introduced in v3.5[1]. I'm looking
for a fix.

Marc

[1] 1c6c695 genirq: Reject bogus threaded irq requests

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
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