On Wed, Sep 18, 2013 at 11:58:12AM +0100, Sudeep KarkadaNagesha wrote:
> From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@xxxxxxx>
>
> Currently we need to replicate the OPP entries in all the nodes even
> though they share OPPs being in the same clock domain.
>
> Few drivers like cpufreq depend on physical cpu0 node to specify the
> OPPs and only that node is referred irrespective of the logical cpu
> accessing it. Alternatively to support cpuhotplug path, few drivers
> parse all the cpu nodes for OPPs. Instead we can specify the phandle
> of the node which contains the OPP tuples.
>
> This patch adds support to the new property 'operating-points-phandle'
> which specifies the phandle pointing to another node which contains the
> actual OPP tuples.
>
> Cc: Rob Herring <rob.herring@xxxxxxxxxxx>
> Cc: Pawel Moll <pawel.moll@xxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Kumar Gala <galak@xxxxxxxxxxxxxx>
> Cc: Stephen Warren <swarren@xxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxx>
> Cc: Nishanth Menon <nm@xxxxxx>
> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@xxxxxxx>
> ---
> drivers/base/power/opp.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
> index ef89897..a450e2f 100644
> --- a/drivers/base/power/opp.c
> +++ b/drivers/base/power/opp.c
> @@ -708,12 +708,20 @@ struct srcu_notifier_head *opp_get_notifier(struct device *dev)
> int of_init_opp_table(struct device *dev)
> {
> const struct property *prop;
> + struct device_node *opp_node;
> const __be32 *val;
> int nr;
>
> - prop = of_find_property(dev->of_node, "operating-points", NULL);
> - if (!prop)
> + opp_node = of_parse_phandle(dev->of_node,
> + "operating-points-phandle", 0);
This will increment the refcount of the node pointed to.
> + if (!opp_node) /* if no OPP phandle, search for OPPs in current node */
> + opp_node = dev->of_node;
> + prop = of_find_property(opp_node, "operating-points", NULL);
> + if (!prop) {
> + dev_warn(dev, "node %s missing operating-points property\n",
> + opp_node->full_name);
> return -ENODEV;
> + }
> if (!prop->value)
> return -ENODATA;
>From the looks of mainline the table gets parsed here, and then the node
is never used again.
At the end there should probably be an of_node_put on the opp_node (if
it's from an operating-points-phandle property).
Cheers,
Mark.
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