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-rw-r--r--drivers/clocksource/Kconfig6
-rw-r--r--drivers/clocksource/Makefile3
-rw-r--r--drivers/clocksource/bcm2835_timer.c9
-rw-r--r--drivers/clocksource/clksrc-of.c35
-rw-r--r--drivers/clocksource/cs5535-clockevt.c11
-rw-r--r--drivers/clocksource/dw_apb_timer_of.c6
-rw-r--r--drivers/clocksource/nomadik-mtu.c33
-rw-r--r--drivers/clocksource/sunxi_timer.c17
-rw-r--r--drivers/clocksource/tcb_clksrc.c7
-rw-r--r--drivers/clocksource/tegra20_timer.c281
-rw-r--r--drivers/clocksource/vt8500_timer.c180
11 files changed, 535 insertions, 53 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 7fdcbd3f4da5..7d978c1bd528 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,3 +1,6 @@
+config CLKSRC_OF
+ bool
+
config CLKSRC_I8253
bool
@@ -25,6 +28,9 @@ config ARMADA_370_XP_TIMER
config SUNXI_TIMER
bool
+config VT8500_TIMER
+ bool
+
config CLKSRC_NOMADIK_MTU
bool
depends on (ARCH_NOMADIK || ARCH_U8500)
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index f93453d01673..596c45c2f192 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_CLKSRC_OF) += clksrc-of.o
obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o
obj-$(CONFIG_X86_CYCLONE_TIMER) += cyclone.o
obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o
@@ -16,5 +17,7 @@ obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o
obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
obj-$(CONFIG_SUNXI_TIMER) += sunxi_timer.o
+obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o
+obj-$(CONFIG_VT8500_TIMER) += vt8500_timer.o
obj-$(CONFIG_CLKSRC_ARM_GENERIC) += arm_generic.o
diff --git a/drivers/clocksource/bcm2835_timer.c b/drivers/clocksource/bcm2835_timer.c
index bc19f12c20ce..50c68fef944b 100644
--- a/drivers/clocksource/bcm2835_timer.c
+++ b/drivers/clocksource/bcm2835_timer.c
@@ -16,7 +16,6 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#include <linux/bcm2835_timer.h>
#include <linux/bitops.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
@@ -101,7 +100,7 @@ static struct of_device_id bcm2835_time_match[] __initconst = {
{}
};
-static void __init bcm2835_time_init(void)
+static void __init bcm2835_timer_init(void)
{
struct device_node *node;
void __iomem *base;
@@ -155,7 +154,5 @@ static void __init bcm2835_time_init(void)
pr_info("bcm2835: system timer (irq = %d)\n", irq);
}
-
-struct sys_timer bcm2835_timer = {
- .init = bcm2835_time_init,
-};
+CLOCKSOURCE_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
+ bcm2835_timer_init);
diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
new file mode 100644
index 000000000000..bdabdaa8d00f
--- /dev/null
+++ b/drivers/clocksource/clksrc-of.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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/init.h>
+#include <linux/of.h>
+
+extern struct of_device_id __clksrc_of_table[];
+
+static const struct of_device_id __clksrc_of_table_sentinel
+ __used __section(__clksrc_of_table_end);
+
+void __init clocksource_of_init(void)
+{
+ struct device_node *np;
+ const struct of_device_id *match;
+ void (*init_func)(void);
+
+ for_each_matching_node_and_match(np, __clksrc_of_table, &match) {
+ init_func = match->data;
+ init_func();
+ }
+}
diff --git a/drivers/clocksource/cs5535-clockevt.c b/drivers/clocksource/cs5535-clockevt.c
index d9279385304d..ea210482dd20 100644
--- a/drivers/clocksource/cs5535-clockevt.c
+++ b/drivers/clocksource/cs5535-clockevt.c
@@ -100,7 +100,6 @@ static struct clock_event_device cs5535_clockevent = {
.set_mode = mfgpt_set_mode,
.set_next_event = mfgpt_next_event,
.rating = 250,
- .shift = 32
};
static irqreturn_t mfgpt_tick(int irq, void *dev_id)
@@ -169,17 +168,11 @@ static int __init cs5535_mfgpt_init(void)
cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_SETUP, val);
/* Set up the clock event */
- cs5535_clockevent.mult = div_sc(MFGPT_HZ, NSEC_PER_SEC,
- cs5535_clockevent.shift);
- cs5535_clockevent.min_delta_ns = clockevent_delta2ns(0xF,
- &cs5535_clockevent);
- cs5535_clockevent.max_delta_ns = clockevent_delta2ns(0xFFFE,
- &cs5535_clockevent);
-
printk(KERN_INFO DRV_NAME
": Registering MFGPT timer as a clock event, using IRQ %d\n",
timer_irq);
- clockevents_register_device(&cs5535_clockevent);
+ clockevents_config_and_register(&cs5535_clockevent, MFGPT_HZ,
+ 0xF, 0xFFFE);
return 0;
diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c
index f7dba5b79b44..ab09ed3742ee 100644
--- a/drivers/clocksource/dw_apb_timer_of.c
+++ b/drivers/clocksource/dw_apb_timer_of.c
@@ -107,7 +107,7 @@ static const struct of_device_id osctimer_ids[] __initconst = {
{},
};
-static void __init timer_init(void)
+void __init dw_apb_timer_init(void)
{
struct device_node *event_timer, *source_timer;
@@ -125,7 +125,3 @@ static void __init timer_init(void)
init_sched_clock();
}
-
-struct sys_timer dw_apb_timer = {
- .init = timer_init,
-};
diff --git a/drivers/clocksource/nomadik-mtu.c b/drivers/clocksource/nomadik-mtu.c
index 8914c3c1c88b..025afc6dd324 100644
--- a/drivers/clocksource/nomadik-mtu.c
+++ b/drivers/clocksource/nomadik-mtu.c
@@ -134,12 +134,32 @@ static void nmdk_clkevt_mode(enum clock_event_mode mode,
}
}
+void nmdk_clksrc_reset(void)
+{
+ /* Disable */
+ writel(0, mtu_base + MTU_CR(0));
+
+ /* ClockSource: configure load and background-load, and fire it up */
+ writel(nmdk_cycle, mtu_base + MTU_LR(0));
+ writel(nmdk_cycle, mtu_base + MTU_BGLR(0));
+
+ writel(clk_prescale | MTU_CRn_32BITS | MTU_CRn_ENA,
+ mtu_base + MTU_CR(0));
+}
+
+static void nmdk_clkevt_resume(struct clock_event_device *cedev)
+{
+ nmdk_clkevt_reset();
+ nmdk_clksrc_reset();
+}
+
static struct clock_event_device nmdk_clkevt = {
.name = "mtu_1",
.features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
.rating = 200,
.set_mode = nmdk_clkevt_mode,
.set_next_event = nmdk_clkevt_next,
+ .resume = nmdk_clkevt_resume,
};
/*
@@ -161,19 +181,6 @@ static struct irqaction nmdk_timer_irq = {
.dev_id = &nmdk_clkevt,
};
-void nmdk_clksrc_reset(void)
-{
- /* Disable */
- writel(0, mtu_base + MTU_CR(0));
-
- /* ClockSource: configure load and background-load, and fire it up */
- writel(nmdk_cycle, mtu_base + MTU_LR(0));
- writel(nmdk_cycle, mtu_base + MTU_BGLR(0));
-
- writel(clk_prescale | MTU_CRn_32BITS | MTU_CRn_ENA,
- mtu_base + MTU_CR(0));
-}
-
void __init nmdk_timer_init(void __iomem *base, int irq)
{
unsigned long rate;
diff --git a/drivers/clocksource/sunxi_timer.c b/drivers/clocksource/sunxi_timer.c
index 93d09d0e009f..4086b9167159 100644
--- a/drivers/clocksource/sunxi_timer.c
+++ b/drivers/clocksource/sunxi_timer.c
@@ -74,7 +74,6 @@ static int sunxi_clkevt_next_event(unsigned long evt,
static struct clock_event_device sunxi_clockevent = {
.name = "sunxi_tick",
- .shift = 32,
.rating = 300,
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.set_mode = sunxi_clkevt_mode,
@@ -104,7 +103,7 @@ static struct of_device_id sunxi_timer_dt_ids[] = {
{ }
};
-static void __init sunxi_timer_init(void)
+void __init sunxi_timer_init(void)
{
struct device_node *node;
unsigned long rate = 0;
@@ -154,18 +153,8 @@ static void __init sunxi_timer_init(void)
val = readl(timer_base + TIMER_CTL_REG);
writel(val | TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG);
- sunxi_clockevent.mult = div_sc(rate / TIMER_SCAL,
- NSEC_PER_SEC,
- sunxi_clockevent.shift);
- sunxi_clockevent.max_delta_ns = clockevent_delta2ns(0xff,
- &sunxi_clockevent);
- sunxi_clockevent.min_delta_ns = clockevent_delta2ns(0x1,
- &sunxi_clockevent);
sunxi_clockevent.cpumask = cpumask_of(0);
- clockevents_register_device(&sunxi_clockevent);
+ clockevents_config_and_register(&sunxi_clockevent, rate / TIMER_SCAL,
+ 0x1, 0xff);
}
-
-struct sys_timer sunxi_timer = {
- .init = sunxi_timer_init,
-};
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
index 32cb929b8eb6..8a6187225dd0 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/tcb_clksrc.c
@@ -157,7 +157,6 @@ static struct tc_clkevt_device clkevt = {
.name = "tc_clkevt",
.features = CLOCK_EVT_FEAT_PERIODIC
| CLOCK_EVT_FEAT_ONESHOT,
- .shift = 32,
/* Should be lower than at91rm9200's system timer */
.rating = 125,
.set_next_event = tc_next_event,
@@ -196,13 +195,9 @@ static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
timer_clock = clk32k_divisor_idx;
- clkevt.clkevt.mult = div_sc(32768, NSEC_PER_SEC, clkevt.clkevt.shift);
- clkevt.clkevt.max_delta_ns
- = clockevent_delta2ns(0xffff, &clkevt.clkevt);
- clkevt.clkevt.min_delta_ns = clockevent_delta2ns(1, &clkevt.clkevt) + 1;
clkevt.clkevt.cpumask = cpumask_of(0);
- clockevents_register_device(&clkevt.clkevt);
+ clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
setup_irq(irq, &tc_irqaction);
}
diff --git a/drivers/clocksource/tegra20_timer.c b/drivers/clocksource/tegra20_timer.c
new file mode 100644
index 000000000000..0bde03feb095
--- /dev/null
+++ b/drivers/clocksource/tegra20_timer.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ * Colin Cross <ccross@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/mach/time.h>
+#include <asm/smp_twd.h>
+#include <asm/sched_clock.h>
+
+#define RTC_SECONDS 0x08
+#define RTC_SHADOW_SECONDS 0x0c
+#define RTC_MILLISECONDS 0x10
+
+#define TIMERUS_CNTR_1US 0x10
+#define TIMERUS_USEC_CFG 0x14
+#define TIMERUS_CNTR_FREEZE 0x4c
+
+#define TIMER1_BASE 0x0
+#define TIMER2_BASE 0x8
+#define TIMER3_BASE 0x50
+#define TIMER4_BASE 0x58
+
+#define TIMER_PTV 0x0
+#define TIMER_PCR 0x4
+
+static void __iomem *timer_reg_base;
+static void __iomem *rtc_base;
+
+static struct timespec persistent_ts;
+static u64 persistent_ms, last_persistent_ms;
+
+#define timer_writel(value, reg) \
+ __raw_writel(value, timer_reg_base + (reg))
+#define timer_readl(reg) \
+ __raw_readl(timer_reg_base + (reg))
+
+static int tegra_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ u32 reg;
+
+ reg = 0x80000000 | ((cycles > 1) ? (cycles-1) : 0);
+ timer_writel(reg, TIMER3_BASE + TIMER_PTV);
+
+ return 0;
+}
+
+static void tegra_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ u32 reg;
+
+ timer_writel(0, TIMER3_BASE + TIMER_PTV);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ reg = 0xC0000000 | ((1000000/HZ)-1);
+ timer_writel(reg, TIMER3_BASE + TIMER_PTV);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+}
+
+static struct clock_event_device tegra_clockevent = {
+ .name = "timer0",
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
+ .set_next_event = tegra_timer_set_next_event,
+ .set_mode = tegra_timer_set_mode,
+};
+
+static u32 notrace tegra_read_sched_clock(void)
+{
+ return timer_readl(TIMERUS_CNTR_1US);
+}
+
+/*
+ * tegra_rtc_read - Reads the Tegra RTC registers
+ * Care must be taken that this funciton is not called while the
+ * tegra_rtc driver could be executing to avoid race conditions
+ * on the RTC shadow register
+ */
+static u64 tegra_rtc_read_ms(void)
+{
+ u32 ms = readl(rtc_base + RTC_MILLISECONDS);
+ u32 s = readl(rtc_base + RTC_SHADOW_SECONDS);
+ return (u64)s * MSEC_PER_SEC + ms;
+}
+
+/*
+ * tegra_read_persistent_clock - Return time from a persistent clock.
+ *
+ * Reads the time from a source which isn't disabled during PM, the
+ * 32k sync timer. Convert the cycles elapsed since last read into
+ * nsecs and adds to a monotonically increasing timespec.
+ * Care must be taken that this funciton is not called while the
+ * tegra_rtc driver could be executing to avoid race conditions
+ * on the RTC shadow register
+ */
+static void tegra_read_persistent_clock(struct timespec *ts)
+{
+ u64 delta;
+ struct timespec *tsp = &persistent_ts;
+
+ last_persistent_ms = persistent_ms;
+ persistent_ms = tegra_rtc_read_ms();
+ delta = persistent_ms - last_persistent_ms;
+
+ timespec_add_ns(tsp, delta * NSEC_PER_MSEC);
+ *ts = *tsp;
+}
+
+static irqreturn_t tegra_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+ timer_writel(1<<30, TIMER3_BASE + TIMER_PCR);
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction tegra_timer_irq = {
+ .name = "timer0",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_TRIGGER_HIGH,
+ .handler = tegra_timer_interrupt,
+ .dev_id = &tegra_clockevent,
+};
+
+static const struct of_device_id timer_match[] __initconst = {
+ { .compatible = "nvidia,tegra20-timer" },
+ {}
+};
+
+static const struct of_device_id rtc_match[] __initconst = {
+ { .compatible = "nvidia,tegra20-rtc" },
+ {}
+};
+
+static void __init tegra20_init_timer(void)
+{
+ struct device_node *np;
+ struct clk *clk;
+ unsigned long rate;
+ int ret;
+
+ np = of_find_matching_node(NULL, timer_match);
+ if (!np) {
+ pr_err("Failed to find timer DT node\n");
+ BUG();
+ }
+
+ timer_reg_base = of_iomap(np, 0);
+ if (!timer_reg_base) {
+ pr_err("Can't map timer registers\n");
+ BUG();
+ }
+
+ tegra_timer_irq.irq = irq_of_parse_and_map(np, 2);
+ if (tegra_timer_irq.irq <= 0) {
+ pr_err("Failed to map timer IRQ\n");
+ BUG();
+ }
+
+ clk = clk_get_sys("timer", NULL);
+ if (IS_ERR(clk)) {
+ pr_warn("Unable to get timer clock. Assuming 12Mhz input clock.\n");
+ rate = 12000000;
+ } else {
+ clk_prepare_enable(clk);
+ rate = clk_get_rate(clk);
+ }
+
+ of_node_put(np);
+
+ np = of_find_matching_node(NULL, rtc_match);
+ if (!np) {
+ pr_err("Failed to find RTC DT node\n");
+ BUG();
+ }
+
+ rtc_base = of_iomap(np, 0);
+ if (!rtc_base) {
+ pr_err("Can't map RTC registers");
+ BUG();
+ }
+
+ /*
+ * rtc registers are used by read_persistent_clock, keep the rtc clock
+ * enabled
+ */
+ clk = clk_get_sys("rtc-tegra", NULL);
+ if (IS_ERR(clk))
+ pr_warn("Unable to get rtc-tegra clock\n");
+ else
+ clk_prepare_enable(clk);
+
+ of_node_put(np);
+
+ switch (rate) {
+ case 12000000:
+ timer_writel(0x000b, TIMERUS_USEC_CFG);
+ break;
+ case 13000000:
+ timer_writel(0x000c, TIMERUS_USEC_CFG);
+ break;
+ case 19200000:
+ timer_writel(0x045f, TIMERUS_USEC_CFG);
+ break;
+ case 26000000:
+ timer_writel(0x0019, TIMERUS_USEC_CFG);
+ break;
+ default:
+ WARN(1, "Unknown clock rate");
+ }
+
+ setup_sched_clock(tegra_read_sched_clock, 32, 1000000);
+
+ if (clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US,
+ "timer_us", 1000000, 300, 32, clocksource_mmio_readl_up)) {
+ pr_err("Failed to register clocksource\n");
+ BUG();
+ }
+
+ ret = setup_irq(tegra_timer_irq.irq, &tegra_timer_irq);
+ if (ret) {
+ pr_err("Failed to register timer IRQ: %d\n", ret);
+ BUG();
+ }
+
+ tegra_clockevent.cpumask = cpu_all_mask;
+ tegra_clockevent.irq = tegra_timer_irq.irq;
+ clockevents_config_and_register(&tegra_clockevent, 1000000,
+ 0x1, 0x1fffffff);
+#ifdef CONFIG_HAVE_ARM_TWD
+ twd_local_timer_of_register();
+#endif
+ register_persistent_clock(NULL, tegra_read_persistent_clock);
+}
+CLOCKSOURCE_OF_DECLARE(tegra20, "nvidia,tegra20-timer", tegra20_init_timer);
+
+#ifdef CONFIG_PM
+static u32 usec_config;
+
+void tegra_timer_suspend(void)
+{
+ usec_config = timer_readl(TIMERUS_USEC_CFG);
+}
+
+void tegra_timer_resume(void)
+{
+ timer_writel(usec_config, TIMERUS_USEC_CFG);
+}
+#endif
diff --git a/drivers/clocksource/vt8500_timer.c b/drivers/clocksource/vt8500_timer.c
new file mode 100644
index 000000000000..8efc86b5b5dd
--- /dev/null
+++ b/drivers/clocksource/vt8500_timer.c
@@ -0,0 +1,180 @@
+/*
+ * arch/arm/mach-vt8500/timer.c
+ *
+ * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * 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.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * This file is copied and modified from the original timer.c provided by
+ * Alexey Charkov. Minor changes have been made for Device Tree Support.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <asm/mach/time.h>
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define VT8500_TIMER_OFFSET 0x0100
+#define VT8500_TIMER_HZ 3000000
+#define TIMER_MATCH_VAL 0x0000
+#define TIMER_COUNT_VAL 0x0010
+#define TIMER_STATUS_VAL 0x0014
+#define TIMER_IER_VAL 0x001c /* interrupt enable */
+#define TIMER_CTRL_VAL 0x0020
+#define TIMER_AS_VAL 0x0024 /* access status */
+#define TIMER_COUNT_R_ACTIVE (1 << 5) /* not ready for read */
+#define TIMER_COUNT_W_ACTIVE (1 << 4) /* not ready for write */
+#define TIMER_MATCH_W_ACTIVE (1 << 0) /* not ready for write */
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+
+static void __iomem *regbase;
+
+static cycle_t vt8500_timer_read(struct clocksource *cs)
+{
+ int loops = msecs_to_loops(10);
+ writel(3, regbase + TIMER_CTRL_VAL);
+ while ((readl((regbase + TIMER_AS_VAL)) & TIMER_COUNT_R_ACTIVE)
+ && --loops)
+ cpu_relax();
+ return readl(regbase + TIMER_COUNT_VAL);
+}
+
+static struct clocksource clocksource = {
+ .name = "vt8500_timer",
+ .rating = 200,
+ .read = vt8500_timer_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int vt8500_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ int loops = msecs_to_loops(10);
+ cycle_t alarm = clocksource.read(&clocksource) + cycles;
+ while ((readl(regbase + TIMER_AS_VAL) & TIMER_MATCH_W_ACTIVE)
+ && --loops)
+ cpu_relax();
+ writel((unsigned long)alarm, regbase + TIMER_MATCH_VAL);
+
+ if ((signed)(alarm - clocksource.read(&clocksource)) <= 16)
+ return -ETIME;
+
+ writel(1, regbase + TIMER_IER_VAL);
+
+ return 0;
+}
+
+static void vt8500_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_RESUME:
+ case CLOCK_EVT_MODE_PERIODIC:
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ writel(readl(regbase + TIMER_CTRL_VAL) | 1,
+ regbase + TIMER_CTRL_VAL);
+ writel(0, regbase + TIMER_IER_VAL);
+ break;
+ }
+}
+
+static struct clock_event_device clockevent = {
+ .name = "vt8500_timer",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 200,
+ .set_next_event = vt8500_timer_set_next_event,
+ .set_mode = vt8500_timer_set_mode,
+};
+
+static irqreturn_t vt8500_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+ writel(0xf, regbase + TIMER_STATUS_VAL);
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction irq = {
+ .name = "vt8500_timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = vt8500_timer_interrupt,
+ .dev_id = &clockevent,
+};
+
+static struct of_device_id vt8500_timer_ids[] = {
+ { .compatible = "via,vt8500-timer" },
+ { }
+};
+
+static void __init vt8500_timer_init(void)
+{
+ struct device_node *np;
+ int timer_irq;
+
+ np = of_find_matching_node(NULL, vt8500_timer_ids);
+ if (!np) {
+ pr_err("%s: Timer description missing from Device Tree\n",
+ __func__);
+ return;
+ }
+ regbase = of_iomap(np, 0);
+ if (!regbase) {
+ pr_err("%s: Missing iobase description in Device Tree\n",
+ __func__);
+ of_node_put(np);
+ return;
+ }
+ timer_irq = irq_of_parse_and_map(np, 0);
+ if (!timer_irq) {
+ pr_err("%s: Missing irq description in Device Tree\n",
+ __func__);
+ of_node_put(np);
+ return;
+ }
+
+ writel(1, regbase + TIMER_CTRL_VAL);
+ writel(0xf, regbase + TIMER_STATUS_VAL);
+ writel(~0, regbase + TIMER_MATCH_VAL);
+
+ if (clocksource_register_hz(&clocksource, VT8500_TIMER_HZ))
+ pr_err("%s: vt8500_timer_init: clocksource_register failed for %s\n",
+ __func__, clocksource.name);
+
+ clockevent.cpumask = cpumask_of(0);
+
+ if (setup_irq(timer_irq, &irq))
+ pr_err("%s: setup_irq failed for %s\n", __func__,
+ clockevent.name);
+ clockevents_config_and_register(&clockevent, VT8500_TIMER_HZ,
+ 4, 0xf0000000);
+}
+
+CLOCKSOURCE_OF_DECLARE(vt8500, "via,vt8500-timer", vt8500_timer_init)