Re: sdhci-esdhc-imx/v5.0-rc5: i.MX50 system hangs when "per" clock is disabled

Jonathan Neuschäfer
2019-02-10T21:32:44Z

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On Thu, Feb 07, 2019 at 11:52:11PM +0100, Jonathan Neuschäfer wrote:
> However, as soon as the mmc driver (sdhci-esdhc-imx.c) disables clk_per
> in sdhci_esdhc_runtime_suspend[2], the whole system locks up in some way.

I've traced clk prepare/unprepare/enable/disable calls and got this
right before it hangs:

[ 1.280981] sdhci_esdhc_runtime_suspend: unprepare clk_per
[ 1.283356] clk_core_unprepare esdhc1_per_gate
[ 1.285191] clk_core_unprepare esdhc_a_podf
[ 1.286881] clk_core_unprepare esdhc_a_pred
[ 1.288568] clk_core_unprepare esdhc_a_sel
[ 1.290220] clk_core_unprepare pll2_sw

I suspect that there is a dependency on pll2_sw that is not represented
in the imx5 clock driver. I'm comparing it to the Reference Manual now.