Re: [Xenomai] OMAP L138

[Peter Howard <pjh@northern-ridge.com.au>]

On Wed, 2014-04-16 at 00:25 +0200, Gilles Chanteperdrix wrote:
> On 04/15/2014 11:59 PM, Peter Howard wrote:
> > On Tue, 2014-04-15 at 13:37 +0200, Gilles Chanteperdrix wrote:
> >> On 04/15/2014 08:03 AM, Peter Howard wrote:
> >>> On Fri, 2014-04-11 at 08:52 +1000, Peter Howard wrote:
> >>>> On Fri, 2014-04-11 at 00:48 +0200, Gilles Chanteperdrix wrote:
> >>>>> On 04/11/2014 12:34 AM, Peter Howard wrote:
> >>>>>> On Fri, 2014-04-11 at 00:23 +0200, Gilles Chanteperdrix wrote:
> >>>>>> (Stripping back conversation on this one - apologies if that's bad
> >>>>>> etiquette for this list)
> >>>>>>  
> >>>>>>> Attachment is better. Also please post the changes you made for omapL138
> >>>>>>>
> >>>>>>
> >>>>>> diff --git a/arch/arm/mach-davinci/Kconfig b/arch/arm/mach-davinci/Kconfig
> >>>>>> index a075b3e..3d8bc59 100644
> >>>>>> --- a/arch/arm/mach-davinci/Kconfig
> >>>>>> +++ b/arch/arm/mach-davinci/Kconfig
> >>>>>> @@ -41,6 +41,8 @@ config ARCH_DAVINCI_DA850
> >>>>>>  	select ARCH_DAVINCI_DA8XX
> >>>>>>  	select ARCH_HAS_CPUFREQ
> >>>>>>  	select CP_INTC
> >>>>>> +    select IPIPE_ARM_KUSER_TSC if IPIPE
> >>>>>> +    select ARM_FCSE if IPIPE
> >>>>>
> >>>>> You may want to leave the choice of enabling or disabling FCSE to the user.
> >>>>>
> >>>>
> >>>> Understood; at the moment the variance on max latency is really bad if
> >>>> you don't enable FCSE.  When I sort out the crashing issues I'll re-test
> >>>> with it off.
> >>>
> >>> Well, FCSE turned out to be my problem.
> >>>
> >>> More specifically,  FCSE and ARM_FCSE_BEST_EFFORT.  Either a) disabling
> >>> ARM_FCSE altogether, or b) selecting ARM_FCSE with ARM_FCSE_GUARENTEED
> >>> gets rid of the crashes/panics with ipipe latency tracing enabled.
> >>>
> >>> So now things seem reasonably stable, I'll go through the full set of
> >>> tests.  Though I still can't do 'xeno-test -l "dohell -l /opt/ltp"' as
> >>> ltp takes out the system without any ipipe/xenomai bits.
> >>>
> >> Ok, FCSE best effort is currently being validated on 3.14, so it may
> >> well be broken. After all, the raw/* branches are work in progress.
> >>
> > 
> > Note: selecting ARM_FCSE_BEST_EFFORT produces the same result on the
> > master branch too . . .
> > 
> 
> Could you turn CONFIG_ARM_FCSE_MESSAGES on and show us the messages you
> get (with the 3.14 kernel, not the master branch)?
> 

OK - sadly there's not much, but here's what I get from the "dies at, or
immediately after, login" rootfs.  That also has all ipipe debugging,
and stack unwinding, enabled.

Arago Project http://arago-project.org arago ttyS2                              
                                                                                
Arago 2011.06 arago ttyS2                                                       
                                                                                
arago login: Unable to handle kernel paging request at virtual address e5902f10 
fcse pid: 0, 0x00000000, hw pid: 0x00000000                                     
pgd = c6934000, hw pgd = c6934000                                               
[e5902f10] *pgd=00000000                                                        
Internal error: Oops: 80000005 [#1] PREEMPT ARM                                 
Modules linked in:                                                              
CPU: 0 PID: 2456 Comm: matrix_guiE Not tainted 3.12.0-ipipe-12092-g1f7fa99-dirt7
task: c7221b00 ti: c7192000 task.ti: c7192000                                   
PC is at 0xe5902f10                                                             
Unable to handle kernel paging request at virtual address ebff3ace              
fcse pid: 93, 0xba000000, hw pid: 0xba000000                                    
pgd = c6908000, hw pgd = c6908000                                               
[ebff3ace] *pgd=00000000                                                        
Internal error: Oops: 80000005 [#2] PREEMPT ARM                                 
Modules linked in:                                                              
CPU: 0 PID: 2429 Comm: klogd Not tainted 3.12.0-ipipe-12092-g1f7fa99-dirty #47  
task: c7226900 ti: c7180000 task.ti: c7180000                                   
PC is at 0xebff3ace                                                             
Unable to handle kernel paging request at virtual address 8148c464              
fcse pid: 0, 0x00000000, hw pid: 0x00000000                                     
pgd = c6934000, hw pgd = c6934000                                               
[8148c464] *pgd=00000000                                                     

That goes on for a while longer, but it's just variations on the same
error.

(Without FCSE debugging enabled, you just get garbage and lockup)

If I can get anything useful out of my other rootfs setup I'll post
that.

-- 
Peter Howard <pjh@northern-ridge.com.au>