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Diffstat (limited to 'arch/arm/mach-ux500/timer.c')
-rw-r--r--arch/arm/mach-ux500/timer.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/timer.c b/arch/arm/mach-ux500/timer.c
new file mode 100644
index 00000000..b6bd0efc
--- /dev/null
+++ b/arch/arm/mach-ux500/timer.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Mattias Wallin <mattias.wallin@stericsson.com> for ST-Ericsson
+ */
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/clksrc-dbx500-prcmu.h>
+#include <linux/clocksource.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_data/clocksource-nomadik-mtu.h>
+
+#include <asm/smp_twd.h>
+
+#include "setup.h"
+#include "irqs.h"
+
+#include "db8500-regs.h"
+#include "id.h"
+
+#ifdef CONFIG_HAVE_ARM_TWD
+static DEFINE_TWD_LOCAL_TIMER(u8500_twd_local_timer,
+ U8500_TWD_BASE, IRQ_LOCALTIMER);
+
+static void __init ux500_twd_init(void)
+{
+ struct twd_local_timer *twd_local_timer;
+ int err;
+
+ /* Use this to switch local timer base if changed in new ASICs */
+ twd_local_timer = &u8500_twd_local_timer;
+
+ if (of_have_populated_dt())
+ clocksource_of_init();
+ else {
+ err = twd_local_timer_register(twd_local_timer);
+ if (err)
+ pr_err("twd_local_timer_register failed %d\n", err);
+ }
+}
+#else
+#define ux500_twd_init() do { } while(0)
+#endif
+
+const static struct of_device_id prcmu_timer_of_match[] __initconst = {
+ { .compatible = "stericsson,db8500-prcmu-timer-4", },
+ { },
+};
+
+void __init ux500_timer_init(void)
+{
+ void __iomem *mtu_timer_base;
+ void __iomem *prcmu_timer_base;
+ void __iomem *tmp_base;
+ struct device_node *np;
+
+ if (cpu_is_u8500_family() || cpu_is_ux540_family()) {
+ mtu_timer_base = __io_address(U8500_MTU0_BASE);
+ prcmu_timer_base = __io_address(U8500_PRCMU_TIMER_4_BASE);
+ } else {
+ ux500_unknown_soc();
+ }
+
+ /* TODO: Once MTU has been DT:ed place code above into else. */
+ if (of_have_populated_dt()) {
+#ifdef CONFIG_OF
+ np = of_find_matching_node(NULL, prcmu_timer_of_match);
+ if (!np)
+#endif
+ goto dt_fail;
+
+ tmp_base = of_iomap(np, 0);
+ if (!tmp_base)
+ goto dt_fail;
+
+ prcmu_timer_base = tmp_base;
+ }
+
+dt_fail:
+ /* Doing it the old fashioned way. */
+
+ /*
+ * Here we register the timerblocks active in the system.
+ * Localtimers (twd) is started when both cpu is up and running.
+ * MTU register a clocksource, clockevent and sched_clock.
+ * Since the MTU is located in the VAPE power domain
+ * it will be cleared in sleep which makes it unsuitable.
+ * We however need it as a timer tick (clockevent)
+ * during boot to calibrate delay until twd is started.
+ * RTC-RTT have problems as timer tick during boot since it is
+ * depending on delay which is not yet calibrated. RTC-RTT is in the
+ * always-on powerdomain and is used as clockevent instead of twd when
+ * sleeping.
+ * The PRCMU timer 4 register a clocksource and
+ * sched_clock with higher rating then MTU since is always-on.
+ *
+ */
+
+ nmdk_timer_init(mtu_timer_base, IRQ_MTU0);
+ clksrc_dbx500_prcmu_init(prcmu_timer_base);
+ ux500_twd_init();
+}