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authorDinh Nguyen <dinguyen@altera.com>2012-07-11 15:13:16 -0500
committerArnd Bergmann <arnd@arndb.de>2012-07-12 17:26:09 +0200
commitcfda590178a16e2b5edb09e131460b3e64819807 (patch)
tree7104a9bb75d101dcdc82c331e9cdd075eab702dc /drivers/clocksource/dw_apb_timer_of.c
parentbd0a521e88aa7a06ae7aabaed7ae196ed4ad867a (diff)
clocksource: dw_apb_timer: Add common DTS glue for dw_apb_timer
Make a common device tree glue for clocksource/dw_apb_timer. Move mach-picoxcell/time.c to be a generic device tree application of the dw_apb_timer. Configure mach-picoxcell to use the dw_apb_timer_of device tree implementation in drivers/clocksource. Signed-off-by: Pavel Machek <pavel@denx.de> Signed-off-by: Dinh Nguyen <dinguyen@altera.com> Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/clocksource/dw_apb_timer_of.c')
-rw-r--r--drivers/clocksource/dw_apb_timer_of.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c
new file mode 100644
index 000000000000..f7dba5b79b44
--- /dev/null
+++ b/drivers/clocksource/dw_apb_timer_of.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2012 Altera Corporation
+ * Copyright (c) 2011 Picochip Ltd., Jamie Iles
+ *
+ * Modified from mach-picoxcell/time.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/dw_apb_timer.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/mach/time.h>
+#include <asm/sched_clock.h>
+
+static void timer_get_base_and_rate(struct device_node *np,
+ void __iomem **base, u32 *rate)
+{
+ *base = of_iomap(np, 0);
+
+ if (!*base)
+ panic("Unable to map regs for %s", np->name);
+
+ if (of_property_read_u32(np, "clock-freq", rate) &&
+ of_property_read_u32(np, "clock-frequency", rate))
+ panic("No clock-frequency property for %s", np->name);
+}
+
+static void add_clockevent(struct device_node *event_timer)
+{
+ void __iomem *iobase;
+ struct dw_apb_clock_event_device *ced;
+ u32 irq, rate;
+
+ irq = irq_of_parse_and_map(event_timer, 0);
+ if (irq == NO_IRQ)
+ panic("No IRQ for clock event timer");
+
+ timer_get_base_and_rate(event_timer, &iobase, &rate);
+
+ ced = dw_apb_clockevent_init(0, event_timer->name, 300, iobase, irq,
+ rate);
+ if (!ced)
+ panic("Unable to initialise clockevent device");
+
+ dw_apb_clockevent_register(ced);
+}
+
+static void add_clocksource(struct device_node *source_timer)
+{
+ void __iomem *iobase;
+ struct dw_apb_clocksource *cs;
+ u32 rate;
+
+ timer_get_base_and_rate(source_timer, &iobase, &rate);
+
+ cs = dw_apb_clocksource_init(300, source_timer->name, iobase, rate);
+ if (!cs)
+ panic("Unable to initialise clocksource device");
+
+ dw_apb_clocksource_start(cs);
+ dw_apb_clocksource_register(cs);
+}
+
+static void __iomem *sched_io_base;
+
+static u32 read_sched_clock(void)
+{
+ return __raw_readl(sched_io_base);
+}
+
+static const struct of_device_id sptimer_ids[] __initconst = {
+ { .compatible = "picochip,pc3x2-rtc" },
+ { .compatible = "snps,dw-apb-timer-sp" },
+ { /* Sentinel */ },
+};
+
+static void init_sched_clock(void)
+{
+ struct device_node *sched_timer;
+ u32 rate;
+
+ sched_timer = of_find_matching_node(NULL, sptimer_ids);
+ if (!sched_timer)
+ panic("No RTC for sched clock to use");
+
+ timer_get_base_and_rate(sched_timer, &sched_io_base, &rate);
+ of_node_put(sched_timer);
+
+ setup_sched_clock(read_sched_clock, 32, rate);
+}
+
+static const struct of_device_id osctimer_ids[] __initconst = {
+ { .compatible = "picochip,pc3x2-timer" },
+ { .compatible = "snps,dw-apb-timer-osc" },
+ {},
+};
+
+static void __init timer_init(void)
+{
+ struct device_node *event_timer, *source_timer;
+
+ event_timer = of_find_matching_node(NULL, osctimer_ids);
+ if (!event_timer)
+ panic("No timer for clockevent");
+ add_clockevent(event_timer);
+
+ source_timer = of_find_matching_node(event_timer, osctimer_ids);
+ if (!source_timer)
+ panic("No timer for clocksource");
+ add_clocksource(source_timer);
+
+ of_node_put(source_timer);
+
+ init_sched_clock();
+}
+
+struct sys_timer dw_apb_timer = {
+ .init = timer_init,
+};