Hi Eric, On 17 May 2017 at 16:45, Eric Nelson <eric@xxxxxxxxxx> wrote: > Hi Fawad, > > On 05/17/2017 06:40 AM, Fawad Lateef wrote: >> >> On 15 May 2017 at 16:20, Fawad Lateef <fawadlateef@xxxxxxxxx> wrote: >>> >>> Hi Eric, >>> On 15 May 2017 at 16:12, Eric Nelson <eric@xxxxxxxxxx> wrote: >>>> >>>> Hi Fawad, >>>> >>>>> 发自网易邮箱大师 >>>>> On 05/15/2017 20:44, Fawad Lateef wrote: >>>>> >>>>> Hi All, >>>>> >>>>> I am working on custom i.MX6 quad hardware and using RT patches for >>>>> almost latest stable kernel 4.9 and facing some weird system stall OR >>>>> 'unhandled page fault - exceptions'. >>>>> >>>> >>>> I'm not sure about the unhandled page fault, but the stalls may be >>>> because of the SDMA driver. >>>> >>>> See this patch in the Freescale/NXP community for kernel 4.1: >>>> >>>> https://github.com/Freescale/meta-freescale/blob/master/recipes-kernel/linux/linux-fslc-imx-rt/0003-Work-around-CPU-stalls-in-the-imx-sdma-driver.patch >>>> >>> >>> Thanks for the patch link. I will give it a try. >> >> >> Talked to hardware manufacturer and they applied the patch. >> >> Still that SDMA is only used for NOR flash and only u-boot and its >> environment are stored in nor flash. So not sure if that is going to >> help in any case. >> > > SDMA is used for much more than NOR flash (SSI, USB, and sometimes > UARTs). > Yes SDMA can be used for many devices but in our case its only set to use for NOR (to confirm I also checked sdma interrupts in system and they just 21 or so which happened during boot time). >> So I would really like few more suggestions OR confirmations about ARM >> (cortex-A9 based imx6) (preemept)-RT support/patches are stable and >> can be used for final products. >> > > I don't have any experience with the RT patches on 4.9 or later > kernels, but do know that they're being used on i.MX6 with the > vendor kernels (3.10.x, 4.1.x). > > I believe Alison Chaiken mentioned using them with 4.9 kernels: > http://elinux.org/images/4/42/IRQs-_the_Hard%2C_the_Soft%2C_the_Threaded_and_the_Preemptible.pdf > https://www.youtube.com/watch?v=-pehAzaP1eg&feature=youtu.be&list=PLbzoR-pLrL6pRFP6SOywVJWdEHlmQE51q > Thanks for the video/link. Seems like very informative. Will check it soon. > Regards, > > > Eric Regards, Fawad Lateef _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
