ARM: mvebu: add broken-idle option

The broken-idle option can be activated from the coherency-fabric DT
node. This property allows to disable the idle capability, when the
hardware doesn't support it, like the Seagate Personal Cloud boards.

Signed-off-by: Vincent Donnefort <vdonnefort@gmail.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

2 files changed, 31 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/arm/coherency-fabric.txt b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
index 8dd46617c889..9b5c3f620e65 100644
--- a/Documentation/devicetree/bindings/arm/coherency-fabric.txt
+++ b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
@@ -27,6 +27,11 @@ Required properties:
  * For "marvell,armada-380-coherency-fabric", only one pair is needed
    for the per-CPU fabric registers.
 
+Optional properties:
+
+- broken-idle: boolean to set when the Idle mode is not supported by the
+  hardware.
+
 Examples:
 
 coherency-fabric@d0020200 {
diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
index e8fdb9ceedf0..867ec3385eb5 100644
--- a/arch/arm/mach-mvebu/pmsu.c
+++ b/arch/arm/mach-mvebu/pmsu.c
@@ -379,6 +379,16 @@ static struct notifier_block mvebu_v7_cpu_pm_notifier = {
 
 static struct platform_device mvebu_v7_cpuidle_device;
 
+static int broken_idle(struct device_node *np)
+{
+        if (of_property_read_bool(np, "broken-idle")) {
+                pr_warn("CPU idle is currently broken: disabling\n");
+                return 1;
+        }
+
+        return 0;
+}
+
 static __init int armada_370_cpuidle_init(void)
 {
         struct device_node *np;
@@ -387,7 +397,9 @@ static __init int armada_370_cpuidle_init(void)
         np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
         if (!np)
                 return -ENODEV;
-        of_node_put(np);
+
+        if (broken_idle(np))
+                goto end;
 
         /*
          * On Armada 370, there is "a slow exit process from the deep
@@ -406,6 +418,8 @@ static __init int armada_370_cpuidle_init(void)
         mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
         mvebu_v7_cpuidle_device.name = "cpuidle-armada-370";
 
+end:
+        of_node_put(np);
         return 0;
 }
 
@@ -422,6 +436,10 @@ static __init int armada_38x_cpuidle_init(void)
                                      "marvell,armada-380-coherency-fabric");
         if (!np)
                 return -ENODEV;
+
+        if (broken_idle(np))
+                goto end;
+
         of_node_put(np);
 
         np = of_find_compatible_node(NULL, NULL,
@@ -430,7 +448,6 @@ static __init int armada_38x_cpuidle_init(void)
                 return -ENODEV;
         mpsoc_base = of_iomap(np, 0);
         BUG_ON(!mpsoc_base);
-        of_node_put(np);
 
         /* Set up reset mask when powering down the cpus */
         reg = readl(mpsoc_base + MPCORE_RESET_CTL);
@@ -450,6 +467,8 @@ static __init int armada_38x_cpuidle_init(void)
         mvebu_v7_cpuidle_device.dev.platform_data = armada_38x_cpu_suspend;
         mvebu_v7_cpuidle_device.name = "cpuidle-armada-38x";
 
+end:
+        of_node_put(np);
         return 0;
 }
 
@@ -460,12 +479,16 @@ static __init int armada_xp_cpuidle_init(void)
         np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
         if (!np)
                 return -ENODEV;
-        of_node_put(np);
+
+        if (broken_idle(np))
+                goto end;
 
         mvebu_cpu_resume = armada_370_xp_cpu_resume;
         mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
         mvebu_v7_cpuidle_device.name = "cpuidle-armada-xp";
 
+end:
+        of_node_put(np);
         return 0;
 }