2009/9/16 Kalle Jokiniemi <[email protected]>:
> There is a possible race condition in clockdomain
> code handling hw supported idle transitions.
>
> When multiple autodeps dependencies are being added
> or removed, a transition of still remaining dependent
> powerdomain can result in false readings of the
> state counter. This is especially fatal for off mode
> state counter, as it could result in a driver not
> noticing a context loss.
>
> Fixed by disabling hw supported state transitions
> when autodeps are being changed.
>
> Signed-off-by: Kalle Jokiniemi <[email protected]>
> ---
> arch/arm/mach-omap2/clockdomain.c | 74
> ++++++++++++++++++++++---------------
> 1 files changed, 44 insertions(+), 30 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/clockdomain.c
> b/arch/arm/mach-omap2/clockdomain.c
> index 4ef7b4f..1a8c386 100644
> --- a/arch/arm/mach-omap2/clockdomain.c
> +++ b/arch/arm/mach-omap2/clockdomain.c
> @@ -137,6 +137,36 @@ static void _clkdm_del_autodeps(struct clockdomain
> *clkdm)
> }
> }
>
> +/*
> + * _omap2_clkdm_set_hwsup - set high the hwsup idle transition bit
> + * @clkdm: struct clockdomain *
> + * @enable: int 0 to disable, 1 to enable
> + *
> + * Internal helper for actually switching the bit that controls hwsup
> + * idle transitions for clkdm.
> + */
"static" missing here.
> +void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable)
> +{
> + u32 v;
> +
> + if (cpu_is_omap24xx()) {
> + if (enable)
> + v = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
> + else
> + v = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
> + } else if (cpu_is_omap34xx()) {
> + if (enable)
> + v = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
> + else
> + v = OMAP34XX_CLKSTCTRL_DISABLE_AUTO;
> + } else {
> + BUG();
> + }
> +
> + cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask,
> + v << __ffs(clkdm->clktrctrl_mask),
> + clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
> +}
>
> static struct clockdomain *_clkdm_lookup(const char *name)
> {
[...]
Regards,
Tommi Rantala
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