[Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Manfred]

Dear xenomai-users/developers,

I am currently working with an omap3530 based gumstix overo(fire), and I am
trying to get xenomai running on this platform.
I found quite detailed instructions on this page
(http://www.lara.unb.br/wiki/index.php/Overo_Xenomai)
and after some adaptations (details, see below) was able to get the system to
boot from an SD card, to compile and run the "trivial-periodic" example. 
I am working with kernel linux-omap3-2.6.33 and xenomai 2.5.3 and I checked out
the bitbake recipes from the gumstix-org, overo branch (I could not find the old 
kernel recipes in the overo-2011.3 branch)

However, I do have the following problem:
when I look at the running processes using "top" , i see that a system process
called twl4030-irq is taking 50% of the cpu constantly. This happens when I
connect through the usb-serial port, as well as connecting through ssh (over the
built-in wireless, which probably also depends on the twl4030 routines).

Q1) Is this normal behaviour? (i.e. does xenomai handle these irqs "in software"
and reserves 50% of the cpu for that?) Is there a way to reduce this load
somehow?

Q2) Assuming that it is not normal behaviour, has anyone had already the same
issue?

What I have tried is to disable more twl4030-related modules in the menuconfig
step. However, either it has no effect (still twl4030-irq takes 50% cpu) or then 
he system stopped already at boot-up time.
I then realized that twl4030-irq must be a pretty essential part, since also
twl4030-core is depending on it:
./drivers/mfd/Makefile:29:obj-$(CONFIG_TWL4030_CORE)
  += twl-core.o twl4030-irq.o twl6030-irq.o

So, I assume there is no workaround, based on disabling twl4030-related
kernelmodules (such as SND_SOC_TWL4030 etc.)

Q3) Am I correct in this assumption, or could it still be, that some of the
other drivers are actually "triggering" the twl4030-irq process 
to run continuously?


Looking at the twl4030-irq.c source file, 
I find some "FIX_ME" statements like this:
778 /* FIXME pass in which interrupt line we'll use ... */
779 #define twl_irq_line    0
(http://lxr.free-electrons.com/source/drivers/mfd/twl4030-irq.c?v=2.6.33;a=arm)

Q4) Do I need to be concerned about this? Does it mean, that the twl4030 chipset
is not fully supported yet by the linux kernel drivers? Do I need to make
adaptations  directly into the source  code to get this working?

Q5) Are there any debugging/system tools in xenomai which could help me in
finding out what causes twl4030-irq to be spending that many cpu-cycles?
Attaching with gdb or killing with kill -9 does not work. (using gdb, I get a
error message from ptrace, and just no reaction from kill)


At the end of this message you find a detailed description of how I came to the
current setup, for reference. In case any further information is needed, please
let me know.
By the way, without the xenomai-patch, the standard omap3-2.6.33 kernel does not
have the twl4030-irq process running at 50%. So the problem seems to be either
related to the xenomai-patch or to the other changes that were necessary to make
it run.

Any help with this would be highly appreciated.

Regards,
Manfred

More System Information:
-------------------------
Attachment (1): output related to xenomai and twl4030 in dmesg:
-----------------
ARMv7 Processor [411fc083] revision 3 (ARMv7)
[..]
I-pipe 1.16-01: pipeline enabled
[...]
twl4030: PIH (irq 7) chaining IRQs 368..375
twl4030: power (irq 373) chaining IRQs 376..383
[..]
twl4030: gpio (irq 368) chaining IRQs 384..401
twl4030_usb twl4030_usb: Initialized TWL4030 USB module
[..]
I-pipe: Domain Xenomai registered.
Xenomai: hal/arm started.
Xenomai: scheduling class idle registered.
Xenomai: scheduling class rt registered.
Xenomai: real-time nucleus v2.5.3 (Hordes Of Locusts) loaded.
Xenomai: starting native API services.
Xenomai: starting POSIX services.
Xenomai: starting RTDM services.
[..]
asoc: twl4030 <-> omap-mcbsp-dai-0 mapping ok



Attachment (2): detailed description, how i got to the current setup:
----------------
I have to mention, that I am just getting started with xenomai.For completeness
here are more or less the adaptations that I needed to make to get xenomai
running so far: (it might very well be, that some steps are not necc. but I
did/do not have time to traverse through the decision tree again)
1.) checkout recipes from overo branch (not overo-2011.3): 
(following guidelines here:
http://www.gumstix.org/software-development/open-embedded/
61-using-the-open-embedded-build-system.html )
git clone git://gitorious.org/gumstix-oe/mainline.git org.openembedded.dev
cd org.openembedded.dev
git checkout --track -b overo-2011.03 origin/overo

2.) starting from the standard config files for gumstix:
cp -r org.openembedded.dev/contrib/gumstix/build .
adapting build/conf/local.conf:
BB_NUMBER_THREADS = "16"
PARALLEL_MAKE = "-j 4"
PREFERRED_VERSION_linux-omap3 = "2.6.33"
#disable manpages *for opensp/openjade issue* in overo-branch:
EXTRA_OECONF = " --disable-man-pages --disable-gtk-doc-html "

then touch build/conf/sanity.conf
(I am using /bin/dash and cannot change it *don't have root-access on the
development machine*)

3.) build a standard image:
bitbake -v -k omap3-console-image 2>&1 | tee Bitbaking-omap3-console.log
fix any problems by adapting the corresponding recipes

4.) get the user.collection with the corresponding recipes for xenomai
from here:
http://www.lara.unb.br/wiki/index.php/Overo_Xenomai

5.) run bitbake on the omap3-2.6.33 kernel up to the menuconfig step,
disable usb-gadgets driver and one of the watchdogs (omap or twl4030)
copy the modified .config file from /tmp/work.. to the coresponding
user.collection folder
clean and bitbake omap3-2.6.33
bitbake gumstixwithxenomai (adapted recipe adding the xenomai-userside)

6.) boot from SD card.


Attachment (3): Kernel Config File information:
----------------
A diff of the .config file from the standard omap3-2.6.33 config file (from the
git repository/ overo-branch), with the one I used:
--- defconfig-original-opemb	2011-10-21 11:42:34.000000000 +0200
+++ defconfig.xenomai	2011-10-28 15:37:25.000000000 +0200
@@ -1,7 +1,7 @@
 #
 # Automatically generated make config: don't edit
 # Linux kernel version: 2.6.33
-# Wed Mar 24 06:13:38 2010
+# Tue Oct 25 22:37:04 2011
 #
 CONFIG_ARM=y
 CONFIG_SYS_SUPPORTS_APM_EMULATION=y
@@ -102,7 +102,6 @@
 #
 CONFIG_PERF_EVENTS=y
 # CONFIG_PERF_COUNTERS is not set
-# CONFIG_DEBUG_PERF_USE_VMALLOC is not set
 CONFIG_VM_EVENT_COUNTERS=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_SLAB=y
@@ -175,6 +174,120 @@
 CONFIG_INLINE_WRITE_UNLOCK_IRQ=y
 # CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE is not set
 # CONFIG_MUTEX_SPIN_ON_OWNER is not set
+
+#
+# Real-time sub-system
+#
+CONFIG_XENOMAI=y
+CONFIG_XENO_GENERIC_STACKPOOL=y
+CONFIG_XENO_FASTSYNCH_DEP=y
+CONFIG_XENO_FASTSYNCH=y
+CONFIG_XENO_OPT_NUCLEUS=y
+CONFIG_XENO_OPT_PERVASIVE=y
+CONFIG_XENO_OPT_PRIOCPL=y
+CONFIG_XENO_OPT_PIPELINE_HEAD=y
+# CONFIG_XENO_OPT_SCHED_CLASSES is not set
+CONFIG_XENO_OPT_PIPE=y
+CONFIG_XENO_OPT_PIPE_NRDEV=32
+CONFIG_XENO_OPT_REGISTRY_NRSLOTS=512
+CONFIG_XENO_OPT_SYS_HEAPSZ=256
+CONFIG_XENO_OPT_SYS_STACKPOOLSZ=128
+CONFIG_XENO_OPT_SEM_HEAPSZ=12
+CONFIG_XENO_OPT_GLOBAL_SEM_HEAPSZ=12
+CONFIG_XENO_OPT_STATS=y
+# CONFIG_XENO_OPT_DEBUG is not set
+# CONFIG_XENO_OPT_SHIRQ is not set
+
+#
+# Timing
+#
+# CONFIG_XENO_OPT_TIMING_PERIODIC is not set
+CONFIG_XENO_OPT_TIMING_VIRTICK=1000
+CONFIG_XENO_OPT_TIMING_SCHEDLAT=0
+
+#
+# Scalability
+#
+# CONFIG_XENO_OPT_SCALABLE_SCHED is not set
+CONFIG_XENO_OPT_TIMER_LIST=y
+# CONFIG_XENO_OPT_TIMER_HEAP is not set
+# CONFIG_XENO_OPT_TIMER_WHEEL is not set
+
+#
+# Machine
+#
+CONFIG_IPIPE_WANT_PREEMPTIBLE_SWITCH=y
+CONFIG_XENO_HW_FPU=y
+CONFIG_XENO_HW_UNLOCKED_SWITCH=y
+
+#
+# Interfaces
+#
+CONFIG_XENO_SKIN_NATIVE=y
+CONFIG_XENO_OPT_NATIVE_PERIOD=0
+CONFIG_XENO_OPT_NATIVE_PIPE=y
+CONFIG_XENO_OPT_NATIVE_PIPE_BUFSZ=1024
+CONFIG_XENO_OPT_NATIVE_SEM=y
+CONFIG_XENO_OPT_NATIVE_EVENT=y
+CONFIG_XENO_OPT_NATIVE_MUTEX=y
+CONFIG_XENO_OPT_NATIVE_COND=y
+CONFIG_XENO_OPT_NATIVE_QUEUE=y
+CONFIG_XENO_OPT_NATIVE_BUFFER=y
+CONFIG_XENO_OPT_NATIVE_HEAP=y
+CONFIG_XENO_OPT_NATIVE_ALARM=y
+CONFIG_XENO_OPT_NATIVE_MPS=y
+# CONFIG_XENO_OPT_NATIVE_INTR is not set
+CONFIG_XENO_SKIN_POSIX=y
+CONFIG_XENO_OPT_POSIX_PERIOD=0
+# CONFIG_XENO_OPT_POSIX_SHM is not set
+# CONFIG_XENO_OPT_POSIX_INTR is not set
+# CONFIG_XENO_OPT_POSIX_SELECT is not set
+# CONFIG_XENO_OPT_DEBUG_POSIX is not set
+# CONFIG_XENO_SKIN_PSOS is not set
+# CONFIG_XENO_SKIN_UITRON is not set
+# CONFIG_XENO_SKIN_VRTX is not set
+# CONFIG_XENO_SKIN_VXWORKS is not set
+# CONFIG_XENO_SKIN_RTAI is not set
+# CONFIG_XENO_OPT_NOWARN_DEPRECATED is not set
+CONFIG_XENO_SKIN_RTDM=y
+CONFIG_XENO_OPT_RTDM_PERIOD=0
+CONFIG_XENO_OPT_RTDM_FILDES=128
+# CONFIG_XENO_OPT_RTDM_SELECT is not set
+
+#
+# Drivers
+#
+
+#
+# Serial drivers
+#
+# CONFIG_XENO_DRIVERS_16550A is not set
+
+#
+# Testing drivers
+#
+# CONFIG_XENO_DRIVERS_TESTING_LEGACY_NAMES is not set
+CONFIG_XENO_DRIVERS_TIMERBENCH=y
+# CONFIG_XENO_DRIVERS_KLATENCY is not set
+# CONFIG_XENO_DRIVERS_IRQBENCH is not set
+CONFIG_XENO_DRIVERS_SWITCHTEST=y
+# CONFIG_XENO_DRIVERS_SIGTEST is not set
+# CONFIG_XENO_DRIVERS_RTDMTEST is not set
+
+#
+# CAN drivers
+#
+# CONFIG_XENO_DRIVERS_CAN is not set
+
+#
+# ANALOGY drivers
+#
+# CONFIG_XENO_DRIVERS_ANALOGY is not set
+
+#
+# Real-time IPC drivers
+#
+# CONFIG_XENO_DRIVERS_RTIPC is not set
 CONFIG_FREEZER=y
 
 #
@@ -246,10 +359,9 @@
 # CONFIG_OMAP_MUX is not set
 CONFIG_OMAP_MCBSP=y
 # CONFIG_OMAP_MBOX_FWK is not set
-# CONFIG_OMAP_MPU_TIMER is not set
-CONFIG_OMAP_32K_TIMER=y
+CONFIG_OMAP_MPU_TIMER=y
+# CONFIG_OMAP_32K_TIMER is not set
 # CONFIG_OMAP3_L2_AUX_SECURE_SAVE_RESTORE is not set
-CONFIG_OMAP_32K_TIMER_HZ=128
 CONFIG_OMAP_DM_TIMER=y
 # CONFIG_OMAP_PM_NONE is not set
 CONFIG_OMAP_PM_NOOP=y
@@ -327,10 +439,14 @@
 # CONFIG_VMSPLIT_2G is not set
 # CONFIG_VMSPLIT_1G is not set
 CONFIG_PAGE_OFFSET=0xC0000000
+CONFIG_IPIPE=y
+CONFIG_IPIPE_DOMAINS=4
+CONFIG_IPIPE_DELAYED_ATOMICSW=y
+# CONFIG_IPIPE_UNMASKED_CONTEXT_SWITCH is not set
 CONFIG_PREEMPT_NONE=y
 # CONFIG_PREEMPT_VOLUNTARY is not set
 # CONFIG_PREEMPT is not set
-CONFIG_HZ=128
+CONFIG_HZ=100
 # CONFIG_THUMB2_KERNEL is not set
 CONFIG_AEABI=y
 # CONFIG_OABI_COMPAT is not set
@@ -369,21 +485,7 @@
 #
 # CPU Power Management
 #
-CONFIG_CPU_FREQ=y
-CONFIG_CPU_FREQ_TABLE=y
-CONFIG_CPU_FREQ_DEBUG=y
-CONFIG_CPU_FREQ_STAT=y
-CONFIG_CPU_FREQ_STAT_DETAILS=y
-# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
-# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
-# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
-CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
-# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
-CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
-CONFIG_CPU_FREQ_GOV_POWERSAVE=y
-CONFIG_CPU_FREQ_GOV_USERSPACE=y
-CONFIG_CPU_FREQ_GOV_ONDEMAND=y
-CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y
+# CONFIG_CPU_FREQ is not set
 # CONFIG_CPU_IDLE is not set
 
 #
@@ -588,8 +690,6 @@
 CONFIG_FW_LOADER=y
 CONFIG_FIRMWARE_IN_KERNEL=y
 CONFIG_EXTRA_FIRMWARE=""
-# CONFIG_DEBUG_DRIVER is not set
-# CONFIG_DEBUG_DEVRES is not set
 # CONFIG_SYS_HYPERVISOR is not set
 # CONFIG_CONNECTOR is not set
 CONFIG_MTD=y
@@ -671,12 +771,6 @@
 # CONFIG_MTD_NAND_PLATFORM is not set
 # CONFIG_MTD_ALAUDA is not set
 # CONFIG_MTD_ONENAND is not set
-# CONFIG_MTD_ONENAND_VERIFY_WRITE is not set
-# CONFIG_MTD_ONENAND_GENERIC is not set
-# CONFIG_MTD_ONENAND_OMAP2 is not set
-# CONFIG_MTD_ONENAND_OTP is not set
-# CONFIG_MTD_ONENAND_2X_PROGRAM is not set
-# CONFIG_MTD_ONENAND_SIM is not set
 
 #
 # LPDDR flash memory drivers
@@ -1103,7 +1197,6 @@
 # CONFIG_I2C_DEBUG_BUS is not set
 # CONFIG_I2C_DEBUG_CHIP is not set
 CONFIG_SPI=y
-# CONFIG_SPI_DEBUG is not set
 CONFIG_SPI_MASTER=y
 
 #
@@ -1127,7 +1220,6 @@
 # CONFIG_PPS is not set
 CONFIG_ARCH_REQUIRE_GPIOLIB=y
 CONFIG_GPIOLIB=y
-CONFIG_DEBUG_GPIO=y
 CONFIG_GPIO_SYSFS=y
 
 #
@@ -1246,7 +1338,7 @@
 #
 # CONFIG_SOFT_WATCHDOG is not set
 CONFIG_OMAP_WATCHDOG=y
-CONFIG_TWL4030_WATCHDOG=y
+# CONFIG_TWL4030_WATCHDOG is not set
 
 #
 # USB-based Watchdog Cards
@@ -1608,6 +1700,7 @@
 CONFIG_PANEL_SAMSUNG_LTE430WQ_F0C=y
 CONFIG_PANEL_SHARP_LS037V7DW01=y
 # CONFIG_PANEL_SHARP_LQ043T1DG01 is not set
+# CONFIG_PANEL_TAAL is not set
 # CONFIG_PANEL_TOPPOLY_TDO35S is not set
 # CONFIG_PANEL_TPO_TD043MTEA1 is not set
 CONFIG_BACKLIGHT_LCD_SUPPORT=y
@@ -1694,7 +1787,6 @@
 CONFIG_SND_OMAP_SOC=y
 CONFIG_SND_OMAP_SOC_MCBSP=y
 CONFIG_SND_OMAP_SOC_OVERO=y
-# CONFIG_SND_OMAP_SOC_OMAP3_BEAGLE is not set
 CONFIG_SND_OMAP_SOC_IGEP0020=y
 CONFIG_SND_SOC_I2C_AND_SPI=y
 # CONFIG_SND_SOC_ALL_CODECS is not set
@@ -1803,7 +1895,6 @@
 CONFIG_USB_MUSB_HOST=y
 # CONFIG_USB_MUSB_PERIPHERAL is not set
 # CONFIG_USB_MUSB_OTG is not set
-# CONFIG_USB_GADGET_MUSB_HDRC is not set
 CONFIG_USB_MUSB_HDRC_HCD=y
 # CONFIG_MUSB_PIO_ONLY is not set
 CONFIG_USB_INVENTRA_DMA=y
@@ -1935,46 +2026,7 @@
 # CONFIG_USB_TEST is not set
 CONFIG_USB_ISIGHTFW=m
 CONFIG_USB_VST=m
-CONFIG_USB_GADGET=y
-# CONFIG_USB_GADGET_DEBUG is not set
-# CONFIG_USB_GADGET_DEBUG_FILES is not set
-# CONFIG_USB_GADGET_DEBUG_FS is not set
-CONFIG_USB_GADGET_VBUS_DRAW=500
-CONFIG_USB_GADGET_SELECTED=y
-# CONFIG_USB_GADGET_AT91 is not set
-# CONFIG_USB_GADGET_ATMEL_USBA is not set
-# CONFIG_USB_GADGET_FSL_USB2 is not set
-# CONFIG_USB_GADGET_LH7A40X is not set
-# CONFIG_USB_GADGET_OMAP is not set
-# CONFIG_USB_GADGET_PXA25X is not set
-# CONFIG_USB_GADGET_R8A66597 is not set
-# CONFIG_USB_GADGET_PXA27X is not set
-# CONFIG_USB_GADGET_S3C_HSOTG is not set
-# CONFIG_USB_GADGET_IMX is not set
-# CONFIG_USB_GADGET_S3C2410 is not set
-# CONFIG_USB_GADGET_M66592 is not set
-# CONFIG_USB_GADGET_AMD5536UDC is not set
-# CONFIG_USB_GADGET_FSL_QE is not set
-# CONFIG_USB_GADGET_CI13XXX is not set
-# CONFIG_USB_GADGET_NET2280 is not set
-# CONFIG_USB_GADGET_GOKU is not set
-# CONFIG_USB_GADGET_LANGWELL is not set
-# CONFIG_USB_GADGET_DUMMY_HCD is not set
-# CONFIG_USB_GADGET_DUALSPEED is not set
-# CONFIG_USB_ZERO is not set
-CONFIG_USB_AUDIO=m
-CONFIG_USB_ETH=m
-CONFIG_USB_ETH_RNDIS=y
-# CONFIG_USB_ETH_EEM is not set
-# CONFIG_USB_GADGETFS is not set
-CONFIG_USB_FILE_STORAGE=m
-# CONFIG_USB_FILE_STORAGE_TEST is not set
-# CONFIG_USB_MASS_STORAGE is not set
-CONFIG_USB_G_SERIAL=m
-# CONFIG_USB_MIDI_GADGET is not set
-CONFIG_USB_G_PRINTER=m
-CONFIG_USB_CDC_COMPOSITE=m
-# CONFIG_USB_G_MULTI is not set
+# CONFIG_USB_GADGET is not set
 
 #
 # OTG and related infrastructure
@@ -2330,49 +2382,13 @@
 # CONFIG_UNUSED_SYMBOLS is not set
 CONFIG_DEBUG_FS=y
 # CONFIG_HEADERS_CHECK is not set
-CONFIG_DEBUG_KERNEL=y
-# CONFIG_DEBUG_SHIRQ is not set
-CONFIG_DETECT_SOFTLOCKUP=y
-# CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC is not set
-CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE=0
-CONFIG_DETECT_HUNG_TASK=y
-# CONFIG_BOOTPARAM_HUNG_TASK_PANIC is not set
-CONFIG_BOOTPARAM_HUNG_TASK_PANIC_VALUE=0
-CONFIG_SCHED_DEBUG=y
-CONFIG_SCHEDSTATS=y
-CONFIG_TIMER_STATS=y
-# CONFIG_DEBUG_OBJECTS is not set
-# CONFIG_DEBUG_SLAB is not set
-# CONFIG_DEBUG_KMEMLEAK is not set
-# CONFIG_DEBUG_RT_MUTEXES is not set
-# CONFIG_RT_MUTEX_TESTER is not set
-# CONFIG_DEBUG_SPINLOCK is not set
-CONFIG_DEBUG_MUTEXES=y
-# CONFIG_DEBUG_LOCK_ALLOC is not set
-# CONFIG_PROVE_LOCKING is not set
-# CONFIG_LOCK_STAT is not set
-# CONFIG_DEBUG_SPINLOCK_SLEEP is not set
-# CONFIG_DEBUG_LOCKING_API_SELFTESTS is not set
-# CONFIG_DEBUG_KOBJECT is not set
-# CONFIG_DEBUG_BUGVERBOSE is not set
-CONFIG_DEBUG_INFO=y
-# CONFIG_DEBUG_VM is not set
-# CONFIG_DEBUG_WRITECOUNT is not set
+# CONFIG_IPIPE_DEBUG is not set
+# CONFIG_DEBUG_KERNEL is not set
+CONFIG_DEBUG_BUGVERBOSE=y
 # CONFIG_DEBUG_MEMORY_INIT is not set
-# CONFIG_DEBUG_LIST is not set
-# CONFIG_DEBUG_SG is not set
-# CONFIG_DEBUG_NOTIFIERS is not set
-# CONFIG_DEBUG_CREDENTIALS is not set
-# CONFIG_BOOT_PRINTK_DELAY is not set
-# CONFIG_RCU_TORTURE_TEST is not set
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
-# CONFIG_BACKTRACE_SELF_TEST is not set
-# CONFIG_DEBUG_BLOCK_EXT_DEVT is not set
-# CONFIG_DEBUG_FORCE_WEAK_PER_CPU is not set
-# CONFIG_FAULT_INJECTION is not set
 # CONFIG_LATENCYTOP is not set
 # CONFIG_SYSCTL_SYSCALL_CHECK is not set
-# CONFIG_PAGE_POISONING is not set
 CONFIG_HAVE_FUNCTION_TRACER=y
 CONFIG_RING_BUFFER=y
 CONFIG_RING_BUFFER_ALLOW_SWAP=y
@@ -2394,12 +2410,8 @@
 # CONFIG_DYNAMIC_DEBUG is not set
 # CONFIG_SAMPLES is not set
 CONFIG_HAVE_ARCH_KGDB=y
-# CONFIG_KGDB is not set
 CONFIG_ARM_UNWIND=y
 # CONFIG_DEBUG_USER is not set
-# CONFIG_DEBUG_ERRORS is not set
-# CONFIG_DEBUG_STACK_USAGE is not set
-# CONFIG_DEBUG_LL is not set
 # CONFIG_OC_ETM is not set

Re: [Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Gilles Chanteperdrix]

On 10/28/2011 04:14 PM, Manfred wrote:
> Dear xenomai-users/developers,
> 
> I am currently working with an omap3530 based gumstix overo(fire), and I am

What version of the Adeos patch? If not the latest (1.18-03), please try
the latest before anything else.

-- 
					    Gilles.

Re: [Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Gilles Chanteperdrix]

On 10/28/2011 06:28 PM, Manfred Quack wrote:
> However: is there a "clean" or "simple" way to apply the adeos-patches
> to the omap3-<>-kernels?

I do not think so. The only answer is: get the omap changes merged into
the mainline kernel, and use the mainline kernel. Because from a
maintenance point of view, maintaining one patch for each version of the
kernel is enough work to want and avoid maintaining versions for several
vendor-specific trees.

That said, if there are not many differences:
- we can arrange for the hunks to apply to both branches (we do this for
the at91 patch);
- we can provide two patches, a pre-patch applied before the adeos patch
(basically reverting all the changes causing conflicts), and a
post-patch applied after the adeos patch solving the conflicts (we did
this for instance for the imx kernel for 2.6.38)

I do not want to do this work for the omap branch, but if someone
provides the patches, we could find a way to make them available in the
tree, making it clear that it is not patches that we validated (for
instance creating a "contrib" directory). I am afraid, however, that
such patches would bitrot rapidly.

-- 
					    Gilles.

Re: [Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Gilles Chanteperdrix]

On 10/28/2011 06:28 PM, Manfred Quack wrote:
> I am using a modified version of the
> adeos-ipipe-2.6.33-arm-1.16-01 patch
> the modifications were made as described on this wiki:
> http://www.lara.unb.br/wiki/index.php/Overo_Xenomai
> and if I understand correctly, the modifications were necc.
> because the omap3-2.6.33 kernel differs from the
> vanilla 2.6.33 kernel.

Also note that around 1.18, latencies on omap3 were greatly improved,
going down from around 90us to 55us at 1kHz, and 35us at 10kHz.

-- 
					    Gilles.

Re: [Xenomai-help] twl4030-irq takes 50%cpu constantly on omap3 gumstix overo

[Gilles Chanteperdrix]

On 10/31/2011 07:39 PM, Manfred Quack wrote:
> I am sorry to bother again ...
> 
> So I managed to compile with 1.16 patch and manually patching in these 
> changes:
> http://git.denx.de/?p=ipipe-2.6.git;a=commitdiff;h=6e5856f8b5383ea25970cbd076956c00b7ee4400 
> 
> http://git.denx.de/?p=ipipe-2.6.git;a=commit;h=153abc5f8a5d86ffab64469206f709191c64d901
> 
> I ran a latency test for ~1h, and generating load by downloading a 700MB 
> .iso over the wireless onto an SD card.
> I first got quite good results, (~60us worst case) but at the end of the 
> test (after ~1h) it suddenly jumped to 5000us (so 5ms).
> Looking at dmesg i got an error message about spurious interrupts:
> 
> Spurious irq 95: 0xffffffdf, please flush posted write for irq 86
> 
> These messages also appear sometimes in the precompiled images (kernel 
> 2.6.39) from the gumstix page. But because the spurious interrupts seem 
> not to create any problems except for the large latency in the 
> latency-tests, I guess it should be possible for the scheduler to reject 
> these spurious interrupts (and provide stable worst-case latency-counts).
> 
> So my question is: Do you know something about these issues, and have 
> they been treated for any of the kernel versions in any i-pipe patch?

This error has nothing to do with the I-pipe kernel, we had many of
these some time ago, but I have not seen one in years. So, the problem
is probably in the patched kernel you use, not in the mainline kernel.
Fortunately, once you found the culprit, it is easy to fix, some
hardware register is written in an interrupt handler which should be
read back right after that, and is not.

But before trying and finding the culprit, you should make sure that the
latency you observe is due to this error. Re-run the same test you ran
on an USB key instead of an SD card for instance. If you do not observe
the high latency re-run the test on the SD card, but run the latency
test on the serial port, to make sure that the kernel message appears at
the time when you get the high latency.

> Which combination of kernel and I-Pipe and xenomai version would you 
> expect to be the most stable/reliable on an omap3530?

The I-pipe patch is validated with mainline kernels by essentially
running the latency head, and generating load with the "dohell" script,
now installed by xenomai. All released patches have been validated.

-- 
                                                                Gilles.