clk: Vexpress-spc: Add clock driver

This patch adds spc clock controller. In Vexpress cpu cluster clock is controlled via
spc controller and so it must be present in clk framework.

vexpress_clk_[of_]register_spc() registers cluster clocks with and without DT.
These are added as root clocks without any parents and their names are
"cluster[0|1|..]".

Now, platform must add clocks of all the cpus below these clusters. cpufreq
driver would get cpu clock and will do clk_get[set]_rate() on cpu clock, which
will then pass it to cluster clocks. And finally spc will get programmed.

This patch doesn't add non-DT clocks for clusters and cpus as i don't see a user
of that for now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/vexpress.h b/include/linux/vexpress.h
index 75818744ab5..698ed67e17b 100644
--- a/include/linux/vexpress.h
+++ b/include/linux/vexpress.h
@@ -123,6 +123,9 @@ void vexpress_restart(char str, const char *cmd);
 struct clk *vexpress_osc_setup(struct device *dev);
 void vexpress_osc_of_setup(struct device_node *node);
 
+struct clk *vexpress_clk_register_spc(const char *name, int cluster_id);
+void vexpress_clk_of_register_spc(void);
+
 void vexpress_clk_init(void __iomem *sp810_base);
 void vexpress_clk_of_init(void);