Hi Lucas, > On 7 Jan 2020, at 18:53, Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote: > > Hi Sébastien, > > On Di, 2020-01-07 at 15:50 +0100, Sébastien Szymanski wrote: >> On 12/10/19 10:31 PM, Sasha Levin wrote: >>> From: Lucas Stach <l.stach@xxxxxxxxxxxxxx> >>> >>> [ Upstream commit c33c585f1b3a99d53920bdac614aca461d8db06f ] >>> >>> If software running before the OCOTP driver is loaded left the >>> controller with the error status pending, the driver will never >>> be able to complete the read timing setup. Reset the error status >>> on probe to make sure the controller is in usable state. >>> >>> Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> >>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> >>> Link: https://lore.kernel.org/r/20191029114240.14905-6-srinivas.kandagatla@xxxxxxxxxx >>> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> >>> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> >>> --- >>> drivers/nvmem/imx-ocotp.c | 4 ++++ >>> 1 file changed, 4 insertions(+) >>> >>> diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c >>> index afb429a417fe0..926d9cc080cf4 100644 >>> --- a/drivers/nvmem/imx-ocotp.c >>> +++ b/drivers/nvmem/imx-ocotp.c >>> @@ -466,6 +466,10 @@ static int imx_ocotp_probe(struct platform_device *pdev) >>> if (IS_ERR(priv->clk)) >>> return PTR_ERR(priv->clk); >>> >>> + clk_prepare_enable(priv->clk); >>> + imx_ocotp_clr_err_if_set(priv->base); >>> + clk_disable_unprepare(priv->clk); >>> + >>> priv->params = of_device_get_match_data(&pdev->dev); >>> imx_ocotp_nvmem_config.size = 4 * priv->params->nregs; >>> imx_ocotp_nvmem_config.dev = dev; >>> >> >> Hi, >> >> This patch makes kernel 4.19.{92,93} hang at boot on my i.MX6ULL based >> board. It hanks at >> >> [ 3.730078] cpu cpu0: Linked as a consumer to regulator.2 >> [ 3.737760] cpu cpu0: Linked as a consumer to regulator.3 >> >> Full boot log is here: https://pastebin.com/TS8EFxkr >> >> The config is imx_v6_v7_defconfig. >> >> Reverting it makes the kernels boot again. > > Can you check if it actually hangs in imx_ocotp_clr_err_if_set(), or if > the clk_disable_unprepare() is the culprit? > > If the clock disable hangs the system there is a missing clock > reference somewhere else that we need to track down. Yes, the system hangs in the imx6q-cpufreq driver, here: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/cpufreq/imx6q-cpufreq.c?h=v4.19.93#n322 Kernel 5.4.8 works thanks to commits: 2733fb0d0699 (“cpufreq: imx6q: read OCOTP through nvmem for imx6ul/imx6ull”) 92f0eb08c66a ("ARM: dts: imx6ul: use nvmem-cells for cpu speed grading”) Regards, -- Sébastien Szymanski, Armadeus Systems Software engineer > > Regards, > Lucas >
