ARM: versatile: Map local timers using Device Tree when possible
Try to map TWD registers basing on a "arm,*-twd-timer" Device Tree
node. This overrides existing twd_base value.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
diff --git a/arch/arm/plat-versatile/localtimer.c b/arch/arm/plat-versatile/localtimer.c
index 0fb3961..e156687 100644
--- a/arch/arm/plat-versatile/localtimer.c
+++ b/arch/arm/plat-versatile/localtimer.c
@@ -11,16 +11,42 @@
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/clockchips.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
#include <asm/smp_twd.h>
#include <asm/localtimer.h>
#include <mach/irqs.h>
+const static struct of_device_id twd_of_match[] __initconst = {
+ { .compatible = "arm,cortex-a9-twd-timer", },
+ { .compatible = "arm,cortex-a5-twd-timer", },
+ { .compatible = "arm,arm11mp-twd-timer", },
+ { },
+};
+
/*
* Setup the local clock events for a CPU.
*/
int __cpuinit local_timer_setup(struct clock_event_device *evt)
{
+#if defined(CONFIG_OF)
+ static int dt_node_probed;
+
+ /* Look for TWD node only once */
+ if (!dt_node_probed) {
+ struct device_node *node = of_find_matching_node(NULL,
+ twd_of_match);
+
+ if (node)
+ twd_base = of_iomap(node, 0);
+
+ dt_node_probed = 1;
+ }
+#endif
+ if (!twd_base)
+ return -ENXIO;
+
evt->irq = IRQ_LOCALTIMER;
twd_timer_setup(evt);
return 0;