On 12/19, Will Newton wrote: > On Tue, Dec 19, 2017 at 2:21 PM, Will Newton <will.newton@xxxxxxxxx> wrote: > > On Tue, Dec 19, 2017 at 9:44 AM, Will Newton <will.newton@xxxxxxxxx> wrote: > >> Hi, > >> > >> I have a git tree with my initial start at msm8909 support in Linux 4.9 here: > >> > >> https://bitbucket.org/andromedauk/msm8909-linux > >> > >> It's based off the Linaro Qualcomm landing team tree (with Android > >> drivers merged too for no useful reason). > >> > >> The current state is that pinctrl is pretty much done, regulators are > >> mostly done, clocks is quite hard to say as I'm not doing a good job > >> of parsing the docs right now. The serial port works! I've seen the > >> USB driver enumerate a hub but not tested any further. The bus clks that you're missing aren't typically exposed in downstream kernels because we don't control the rates of those clks. We've been putting them into upstream to keep the clk tree connected to a root. If you can list the clks that are missing I can give you the info you need. > >> > >> Outstanding tasks: > >> > >> 1. Semi-random resets during boot. Occasionally the board will reset > >> for no obvious reason during boot. I suspect this is something to do > >> with regulators as it usually seems to be around the time something is > >> setting voltage and turning on initcall debugging seems to make it > >> less likely to happen (by slowing the boot). > > > > FWIW these resets go away if I disable the wcnss driver in the dts. > > Specifically the code that triggers the reset is the call to > qcom_scm_pas_auth_and_reset in qcom_wcnss.c. If I comment that call > out then the boot seems to be stable. Does anyone have any ideas what > might cause that behaviour? > The wcnss is probably crashing because some regulator or clk is not enabled, or voltages need to be bumped up. One idea to debug would be to make wcnss into a module that you load with modprobe. Then you can try turning on more regulators, and verify that they're actually on by dumping the SPMI registers, until you narrow down what's off that needs to be on. This would also allow you to confirm the RPM communication is working and regulators are actually working. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html