lkml.org 
[lkml]   [2014]   [Jul]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 18/25] clocksource: clps711x: Add CLPS711X clocksource driver
Date
From: Alexander Shiyan <shc_work@mail.ru>

This adds the clocksource driver for Cirrus Logic CLPS711X series SoCs.
Designed primarily for migration CLPS711X subarch for multiplatform & DT,
for this as the "OF" and "non-OF" calls implemented.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
drivers/clocksource/Makefile | 1 +
drivers/clocksource/clps711x-timer.c | 131 ++++++++++++++++++++++++++++++++++
2 files changed, 132 insertions(+)
create mode 100644 drivers/clocksource/clps711x-timer.c

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index da1ac09..e40435d 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o
obj-$(CONFIG_ORION_TIMER) += time-orion.o
obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
+obj-$(CONFIG_ARCH_CLPS711X) += clps711x-timer.o
obj-$(CONFIG_ARCH_MARCO) += timer-marco.o
obj-$(CONFIG_ARCH_MOXART) += moxart_timer.o
obj-$(CONFIG_ARCH_MXS) += mxs_timer.o
diff --git a/drivers/clocksource/clps711x-timer.c b/drivers/clocksource/clps711x-timer.c
new file mode 100644
index 0000000..d83ec1f
--- /dev/null
+++ b/drivers/clocksource/clps711x-timer.c
@@ -0,0 +1,131 @@
+/*
+ * Cirrus Logic CLPS711X clocksource driver
+ *
+ * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+enum {
+ CLPS711X_CLKSRC_CLOCKSOURCE,
+ CLPS711X_CLKSRC_CLOCKEVENT,
+};
+
+static void __iomem *tcd;
+
+static u64 notrace clps711x_sched_clock_read(void)
+{
+ return ~readw(tcd);
+}
+
+static int __init _clps711x_clksrc_init(struct clk *clock, void __iomem *base)
+{
+ unsigned long rate;
+
+ if (!base)
+ return -ENOMEM;
+ if (IS_ERR(clock))
+ return PTR_ERR(clock);
+
+ rate = clk_get_rate(clock);
+
+ tcd = base;
+
+ clocksource_mmio_init(tcd, "clps711x-clocksource", rate, 300, 16,
+ clocksource_mmio_readw_down);
+
+ sched_clock_register(clps711x_sched_clock_read, 16, rate);
+
+ return 0;
+}
+
+static irqreturn_t clps711x_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static void clps711x_clockevent_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+}
+
+static int __init _clps711x_clkevt_init(struct clk *clock, void __iomem *base,
+ unsigned int irq)
+{
+ struct clock_event_device *clkevt;
+ unsigned long rate;
+
+ if (!irq)
+ return -EINVAL;
+ if (!base)
+ return -ENOMEM;
+ if (IS_ERR(clock))
+ return PTR_ERR(clock);
+
+ clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL);
+ if (!clkevt)
+ return -ENOMEM;
+
+ rate = clk_get_rate(clock);
+
+ /* Set Timer prescaler */
+ writew(DIV_ROUND_CLOSEST(rate, HZ), base);
+
+ clkevt->name = "clps711x-clockevent";
+ clkevt->rating = 300;
+ clkevt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_C3STOP;
+ clkevt->set_mode = clps711x_clockevent_set_mode;
+ clkevt->cpumask = cpumask_of(0);
+ clockevents_config_and_register(clkevt, HZ, 0, 0);
+
+ return request_irq(irq, clps711x_timer_interrupt, IRQF_TIMER,
+ "clps711x-timer", clkevt);
+}
+
+void __init clps711x_clksrc_init(void __iomem *tc1_base, void __iomem *tc2_base,
+ unsigned int irq)
+{
+ struct clk *tc1 = clk_get_sys("clps711x-timer.0", NULL);
+ struct clk *tc2 = clk_get_sys("clps711x-timer.1", NULL);
+
+ BUG_ON(_clps711x_clksrc_init(tc1, tc1_base));
+ BUG_ON(_clps711x_clkevt_init(tc2, tc2_base, irq));
+}
+
+#ifdef CONFIG_CLKSRC_OF
+static void __init clps711x_timer_init(struct device_node *np)
+{
+ unsigned int irq = irq_of_parse_and_map(np, 0);
+ struct clk *clock = of_clk_get(np, 0);
+ void __iomem *base = of_iomap(np, 0);
+
+ switch (of_alias_get_id(np, "timer")) {
+ case CLPS711X_CLKSRC_CLOCKSOURCE:
+ BUG_ON(_clps711x_clksrc_init(clock, base));
+ break;
+ case CLPS711X_CLKSRC_CLOCKEVENT:
+ BUG_ON(_clps711x_clkevt_init(clock, base, irq));
+ break;
+ default:
+ break;
+ }
+}
+CLOCKSOURCE_OF_DECLARE(clps711x, "cirrus,clps711x-timer", clps711x_timer_init);
+#endif
--
1.7.9.5


\
 
 \ /
  Last update: 2014-07-23 13:41    [W:0.162 / U:0.076 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site