* Paul Walmsley <paul@xxxxxxxxx> [081114 09:46]:
>
> During _omap3_noncore_dpll_lock(), if a DPLL has no active downstream
> clocks and DPLL autoidle is enabled, the DPLL may never lock, since it
> will enter autoidle immediately. To resolve this, disable DPLL
> autoidle while locking the DPLL, and unconditionally wait for the DPLL
> to lock. This fixes some bugs where the kernel would hang when returning
> from retention or return the wrong rate for the DPLL.
>
> This patch is a collaboration with Peter de Schrijver
> <peter.de-schrijver@xxxxxxxxx> and Kevin Hilman
> <khilman@xxxxxxxxxxxxxxxxxxx>.
Pushing to l-o tree today.
Tony
> Signed-off-by: Paul Walmsley <paul@xxxxxxxxx>
> Cc: Peter de Schrijver <peter.de-schrijver@xxxxxxxxx>
> Cc: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
> ---
> arch/arm/mach-omap2/clock34xx.c | 15 +++++----------
> 1 files changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c
> index 3a4e160..b8b4494 100644
> --- a/arch/arm/mach-omap2/clock34xx.c
> +++ b/arch/arm/mach-omap2/clock34xx.c
> @@ -163,19 +163,14 @@ static int _omap3_noncore_dpll_lock(struct clk *clk)
>
> ai = omap3_dpll_autoidle_read(clk);
>
> + omap3_dpll_deny_idle(clk);
> +
> _omap3_dpll_write_clken(clk, DPLL_LOCKED);
>
> - if (ai) {
> - /*
> - * If no downstream clocks are enabled, CM_IDLEST bit
> - * may never become active, so don't wait for DPLL to lock.
> - */
> - r = 0;
> + r = _omap3_wait_dpll_status(clk, 1);
> +
> + if (ai)
> omap3_dpll_allow_idle(clk);
> - } else {
> - r = _omap3_wait_dpll_status(clk, 1);
> - omap3_dpll_deny_idle(clk);
> - };
>
> return r;
> }
> --
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