• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 101 subscribers
  • Views 1732 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

dpll_abe_ck failed transition to 'locked'

Michael McDonald1
Prodigy 20 points

I'm trying to boot the omappedia 3.4 Android kernel using u-boot I built from git.denx.de. When the kernel comes up, it indicates it cannot enable the dpll_abe_ck with the message:

                     dpll_abe_ck failed transition to 'locked'

Subsequently, all of the dependent clocks also fail to initialize correctly. This exact same kernel boots fine when flashed to eMMC and booted with TI's boot loader used in omappedia's 5AJ releases.

I believe that u-boot must not be initializing the clocks in the same manner as TI's boot loader.

Does anyone have any ideas as to what the cause of this dpll_abe_ck error might be?

Thanks,

Mike

Kernel and Android were obtained following these instructions:

                http://omapedia.org/wiki/Panda5AJ.1.5.1_Release_Notes

U-Boot was obtained from here:

                git://git.denx.de/u-boot-arm.git

                commit 2931fa4db349c97f882ffda42e901208654b5ca9

  • 0
    TI__Mastermind 29520 points

    Hello Michael,

    I made a comparison between some files in DENX u-boot and TI U-boot. Yes, there are differences, but I don't think that your problem with dpll_abe is on U-boot stage.

    TI u-boot uses  #include <asm/arch/clocks.h>
    Denx u-boot uses            #include <asm/arch/clock.h>

    Try to check the default value of register - CM_CLKMODE_DPLL_ABE[2:0] DPLL_EN - DPLL control in kernel.

    If this bit-filed is 0x7 - Enables the DPLL in Lock mode

    See in files:

    arch/arm/mach-omap2/prcm-54xx-debug_data.c:

    arch/arm/mach-omap2/clock54xx_data.c

    I suggest seeing following patch: https://gitorious.org/linux-omap4-dev/omapboot/source/33af7cb409b603cf7988306ab2ea70f052a9a02b:arch/omap5/configs/config_omap5uevm.h

    OMAPBOOT: OMAP5UEVM: Updating the DPLL_ABE params.

    Best regards,

    Yanko

  • 0 in reply to Yanko Todorov-XID
    Prodigy 20 points

    Thanks for responding. Could you double check that URL you provided. It points to a header file that doesn't appear to have any dpll_abe params in it.

    I still don't understand how the same kernel binary can work under the TI boot loader but get the clock error under u-boot. Seems like a boot loader/kernel interaction issue to me.

  • 0 in reply to Michael McDonald1
    TI__Mastermind 29520 points

    Hello Michael,

    I found the following information in /board-support/linux/arch/arm/mach-omap2/cclock54xx_data.c in Kernel.

    /*
     * OMAP5 ABE DPLL default frequency. In OMAP5430 ES2.0 TRM version R, section
     * "3.6.3.2.3 CKGEN_ABE Clock Generator" states that the "DPLL_ABE_X2_CLK
     * must be set to 196.608 MHz" and hence, the DPLL locked frequency is
     * half of this value.
     */
    #define OMAP5_DPLL_ABE_DEFFREQ                98304000

    However, DPLL_ABE may be disabled in u-boot. 

    Check in /board-support/u-boot/arch/arm/cpu/armv7/omap-common/ clocks-common.c:

    #ifdef CONFIG_SYS_OMAP_ABE_SYSCK - enabled?

    #ifdef CONFIG_SYS_CLOCKS_ENABLE_ALL - enabled?

    #ifdef CONFIG_SYS_OMAP_ABE_SYSCK - enabled?

    Best regards,

    Yanko