Re: [PATCH V1] PCI: imx6: Wait the clocks to stabilize after ref_en

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Hi Richard,

On Fri, Oct 24, 2014 at 12:30 AM, Richard Zhu <richard.zhu@xxxxxxxxxxxxx> wrote:

> -       /* allow the clocks to stabilize */
> -       usleep_range(200, 500);
> -
>         /* power up core phy and enable ref clock */
>         regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
>                         IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
> +       /*
> +        * the async reset input need ref clock to sync internally,
> +        * when the ref clock comes after reset, internal synced
> +        * reset time is too short , cannot meet the requirement.
> +        * add one ~10us delay here.
> +        */
> +       udelay(10);

I am curious about this delay here: have you seen boot issues without
it? If so, which hardware was that?
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