On 2 September 2011 19:14, Kevin Hilman <khilman@xxxxxx> wrote: > javier Martin <javier.martin@xxxxxxxxxxxxxxxxx> writes: > >> On 2 September 2011 08:05, Jarkko Nikula <jarkko.nikula@xxxxxxxxxx> wrote: >>> Other usual things to check that display is off (echo 1 > >>> /sys/class/graphics/fb0/blank) and no cable to musb/otg port. >>> >>> Haven't tried myself with recent kernel but does EHCI and hub on XM let to >>> idle cpu at all? At least on one board having on-board hub I had to disable >>> or unload ehci module in order to hit the retention. >>> >> >> I've checked that too and I've even disabled USB support in the kernel >> just to be sure. But still nothing: >> >> root@beagleboard:~# powertop -d -t 100 >> PowerTOP 1.12 (C) 2007, 2008 Intel Corporation >> >> Collecting data for 100 seconds >> >> >> Cn Avg residency >> C0 (cpu running) ( 0.0%) >> C0 58.5ms (100.0%) >> C1 0.0ms ( 0.0%) >> C2 0.0ms ( 0.0%) >> C3 0.0ms ( 0.0%) >> C4 0.0ms ( 0.0%) >> C5 0.0ms ( 0.0%) >> C6 0.0ms ( 0.0%) >> >> Even when CPU has been idle 100% of the time it doesn't hit any state >> deeper than C0. > > Did you allow the UARTs to idle: Yes I did: root@beagleboard:/sys/devices/system/cpu/cpu0/cpuidle# echo 5 > /sys/devices/platform/omap/omap_uart.0/sleep_timeout root@beagleboard:/sys/devices/system/cpu/cpu0/cpuidle# echo 5 > /sys/devices/platform/omap/omap_uart.1/sleep_timeout root@beagleboard:/sys/devices/system/cpu/cpu0/cpuidle# echo 5 > /sys/devices/platform/omap/omap_uart.2/sleep_timeout root@beagleboard:/sys/devices/system/cpu/cpu0/cpuidle# echo 5 > /sys/devices/platform/omap/omap_uart.3/sleep_timeout [ 65.853820] omap_device: omap_uart.3: new worst case activate latency 0: 30517 [ 65.944366] omap_device: omap_uart.2: new worst case deactivate latency 0: 30517 > # UART timeouts: omap-serial (4th UART only on OMAP36xx and OMAP4) > echo 5 > /sys/devices/platform/omap/omap_uart.0/sleep_timeout > echo 5 > /sys/devices/platform/omap/omap_uart.1/sleep_timeout > echo 5 > /sys/devices/platform/omap/omap_uart.2/sleep_timeout > echo 5 > /sys/devices/platform/omap/omap_uart.3/sleep_timeout > > I just tested this using today's linux-omap master branch (+ merged > v3.1-rc4 which includes a fix for a bootup problem.) > > I booted my Beagle XM with a busybox rootfs on MMC and it worked fine > for me. > > I don't have powertop on the rootfs, but I manually dumped the sysfs > files that powertop reads, so I can see the state times. > > After allowing the UARTs to idle, I see: > > # cd /sys/devices/system/cpu/cpu0 > /sys/devices/system/cpu/cpu0/cpuidle # cat state?/time > 43531831 > 8997 > 157215 > 0 > 3467925 > 0 > 0 OK, I've just tried with the same kernel as you did (linux-omap master + v3.1-rc4 merge) and I can't get any other state than 0: root@beagleboard:/sys/devices/system/cpu/cpu0/cpuidle# cat state?/time 162570397 0 0 0 0 0 0 Just one question. Do you access the shell through UART? What I do is waiting for 20 seconds to allow the UART to suspend and then see state reports. -- Javier Martin Vista Silicon S.L. CDTUC - FASE C - Oficina S-345 Avda de los Castros s/n 39005- Santander. Cantabria. Spain +34 942 25 32 60 www.vista-silicon.com -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
