of_clk_get() is called armada_xp_smp_prepare_cpus() function. This
callback can be called in a context where it should not sleep as pointed
when enabling CONFIG_DEBUG_ATOMIC_SLEEP. However of_clk_get() can sleep.
This patch solved this issue by moving the of_clk_get() during
initialization by gathering the list of reference on the clock, and only
access to this list later.
Fixes: f6cec7cd0777 ("ARM: mvebu: remove device tree parsing for cpu
nodes")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-mvebu/platsmp.c | 32 ++++++++++++++++++++++----------
1 file changed, 22 insertions(+), 10 deletions(-)
diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c
index f9597b701028..33ef7f9f4ef2 100644
--- a/arch/arm/mach-mvebu/platsmp.c
+++ b/arch/arm/mach-mvebu/platsmp.c
@@ -35,17 +35,11 @@
#define AXP_BOOTROM_BASE 0xfff00000
#define AXP_BOOTROM_SIZE 0x100000
+static struct clk *cpu_clks[ARMADA_XP_MAX_CPUS];
+
static struct clk *get_cpu_clk(int cpu)
{
- struct clk *cpu_clk;
- struct device_node *np = of_get_cpu_node(cpu, NULL);
-
- if (WARN(!np, "missing cpu node\n"))
- return NULL;
- cpu_clk = of_clk_get(np, 0);
- if (WARN_ON(IS_ERR(cpu_clk)))
- return NULL;
- return cpu_clk;
+ return cpu_clks[cpu];
}
static void set_secondary_cpu_clock(unsigned int cpu)
@@ -126,7 +120,7 @@ static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
{
struct device_node *node;
struct resource res;
- int err;
+ int err, cpu;
flush_cache_all();
set_cpu_coherent();
@@ -146,6 +140,24 @@ static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
if (res.start != AXP_BOOTROM_BASE ||
resource_size(&res) != AXP_BOOTROM_SIZE)
panic("The address for the BootROM is incorrect");
+
+ /*
+ * of_clk_get() can sleep, but we need a clk reference in
+ * armada_xp_smp_prepare_cpus and the smp_prepare_cpus() call
+ * back must not sleep. So we gather the list of reference on
+ * the clock now.
+ */
+ for (cpu = 0; cpu < ARMADA_XP_MAX_CPUS; cpu++) {
+ struct clk *cpu_clk;
+
+ node = of_get_cpu_node(cpu, NULL);
+ if (WARN(!node, "missing cpu node\n"))
+ continue;
+ cpu_clk = of_clk_get(node, 0);
+ if (WARN_ON(IS_ERR(cpu_clk)))
+ cpu_clk = NULL;
+ cpu_clks[cpu] = cpu_clk;
+ }
}
#ifdef CONFIG_HOTPLUG_CPU
--
2.5.0
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html