ARM: vexpress/TC2: add support for CPU DVFS

SPC(Serial Power Controller) on TC2 also controls the CPU performance
operating points which is essential to provide CPU DVFS. The M3
microcontroller provides two sets of eight performance values, one set
for each cluster (CA15 or CA7). Each of this value contains the
frequency(kHz) and voltage(mV) at that performance level. It expects
these performance level to be passed through the SPC PERF_LVL registers.

This patch adds support to populate these performance levels from M3,
build the mapping to CPU OPPs at the boot and then use it to get and
set the CPU performance level runtime.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Pawel Moll <Pawel.Moll@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/arm/mach-vexpress/tc2_pm.c b/arch/arm/mach-vexpress/tc2_pm.c
index e6eb48192912..d38130aba464 100644
--- a/arch/arm/mach-vexpress/tc2_pm.c
+++ b/arch/arm/mach-vexpress/tc2_pm.c
@@ -16,6 +16,7 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/spinlock.h>
 #include <linux/errno.h>
 #include <linux/irqchip/arm-gic.h>
@@ -311,7 +312,7 @@ static void __naked tc2_pm_power_up_setup(unsigned int affinity_level)
 
 static int __init tc2_pm_init(void)
 {
-	int ret;
+	int ret, irq;
 	void __iomem *scc;
 	u32 a15_cluster_id, a7_cluster_id, sys_info;
 	struct device_node *np;
@@ -336,13 +337,15 @@ static int __init tc2_pm_init(void)
 	tc2_nr_cpus[a15_cluster_id] = (sys_info >> 16) & 0xf;
 	tc2_nr_cpus[a7_cluster_id] = (sys_info >> 20) & 0xf;
 
+	irq = irq_of_parse_and_map(np, 0);
+
 	/*
 	 * A subset of the SCC registers is also used to communicate
 	 * with the SPC (power controller). We need to be able to
 	 * drive it very early in the boot process to power up
 	 * processors, so we initialize the SPC driver here.
 	 */
-	ret = ve_spc_init(scc + SPC_BASE, a15_cluster_id);
+	ret = ve_spc_init(scc + SPC_BASE, a15_cluster_id, irq);
 	if (ret)
 		return ret;