[PATCH 18/19] clocksource: add timer-nationalchip.c
From: Guo Ren
Date: Sun Mar 18 2018 - 15:55:26 EST
Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx>
---
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-nationalchip.c | 149 +++++++++++++++++++++++++++++++
2 files changed, 150 insertions(+)
create mode 100644 drivers/clocksource/timer-nationalchip.c
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index d6dec44..d091712 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -76,3 +76,4 @@ obj-$(CONFIG_H8300_TMR16) += h8300_timer16.o
obj-$(CONFIG_H8300_TPU) += h8300_tpu.o
obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o
obj-$(CONFIG_X86_NUMACHIP) += numachip.o
+obj-$(CONFIG_CSKY) += timer-nationalchip.o
diff --git a/drivers/clocksource/timer-nationalchip.c b/drivers/clocksource/timer-nationalchip.c
new file mode 100644
index 0000000..1279d64
--- /dev/null
+++ b/drivers/clocksource/timer-nationalchip.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou NationalChip Science & Technology Co.,Ltd.
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/param.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/profile.h>
+#include <linux/irq.h>
+#include <linux/rtc.h>
+#include <linux/sizes.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#define NC_VA_COUNTER_1_STATUS (void *)(timer_reg + 0x00)
+#define NC_VA_COUNTER_1_VALUE (void *)(timer_reg + 0x04)
+#define NC_VA_COUNTER_1_CONTROL (void *)(timer_reg + 0x10)
+#define NC_VA_COUNTER_1_CONFIG (void *)(timer_reg + 0x20)
+#define NC_VA_COUNTER_1_PRE (void *)(timer_reg + 0x24)
+#define NC_VA_COUNTER_1_INI (void *)(timer_reg + 0x28)
+#define NC_VA_COUNTER_2_STATUS (void *)(timer_reg + 0x40)
+#define NC_VA_COUNTER_2_VALUE (void *)(timer_reg + 0x44)
+#define NC_VA_COUNTER_2_CONTROL (void *)(timer_reg + 0x50)
+#define NC_VA_COUNTER_2_CONFIG (void *)(timer_reg + 0x60)
+#define NC_VA_COUNTER_2_PRE (void *)(timer_reg + 0x64)
+#define NC_VA_COUNTER_2_INI (void *)(timer_reg + 0x68)
+#define NC_VA_COUNTER_3_STATUS (void *)(timer_reg + 0x80)
+#define NC_VA_COUNTER_3_VALUE (void *)(timer_reg + 0x84)
+#define NC_VA_COUNTER_3_CONTROL (void *)(timer_reg + 0x90)
+#define NC_VA_COUNTER_3_CONFIG (void *)(timer_reg + 0xa0)
+#define NC_VA_COUNTER_3_PRE (void *)(timer_reg + 0xa4)
+#define NC_VA_COUNTER_3_INI (void *)(timer_reg + 0xa8)
+
+static unsigned int timer_reg;
+
+static inline void timer_reset(void)
+{
+ __raw_writel(0x1, NC_VA_COUNTER_1_CONTROL);
+ __raw_writel(0x0, NC_VA_COUNTER_1_CONTROL);
+ __raw_writel(0x3, NC_VA_COUNTER_1_CONFIG);
+ __raw_writel(26, NC_VA_COUNTER_1_PRE);
+}
+
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *dev = (struct clock_event_device *) dev_id;
+
+ __raw_writel(1, NC_VA_COUNTER_1_STATUS);
+
+ dev->event_handler(dev);
+
+ return IRQ_HANDLED;
+}
+
+static int nc_timer_set_periodic(struct clock_event_device *dev)
+{
+ timer_reset();
+
+ __raw_writel(0xFFFFD8EF, NC_VA_COUNTER_1_INI);
+ __raw_writel(0x2, NC_VA_COUNTER_1_CONTROL);
+
+ return 0;
+}
+
+static int nc_timer_set_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+ __raw_writel(0x1, NC_VA_COUNTER_1_CONTROL);
+ __raw_writel(ULONG_MAX - delta, NC_VA_COUNTER_1_INI);
+ __raw_writel(0x2, NC_VA_COUNTER_1_CONTROL);
+ return 0;
+}
+
+static int nc_timer_shutdown(struct clock_event_device *dev)
+{
+ __raw_writel(0x0, NC_VA_COUNTER_1_CONTROL);
+ __raw_writel(0x0, NC_VA_COUNTER_1_CONFIG);
+
+ return 0;
+}
+
+static struct clock_event_device nc_ced = {
+ .name = "nationalchip-clkevent",
+ .features = CLOCK_EVT_FEAT_PERIODIC
+ | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 200,
+ .set_state_shutdown = nc_timer_shutdown,
+ .set_state_periodic = nc_timer_set_periodic,
+ .set_next_event = nc_timer_set_next_event,
+};
+
+static u64 notrace nc_sched_clock_read(void)
+{
+ return (u64) __raw_readl(NC_VA_COUNTER_2_VALUE);
+}
+
+static void nc_csd_enable(void)
+{
+ __raw_writel(0x1, NC_VA_COUNTER_2_CONTROL);
+ __raw_writel(0x0, NC_VA_COUNTER_2_CONTROL);
+ __raw_writel(0x1, NC_VA_COUNTER_2_CONFIG);
+
+ __raw_writel(26,NC_VA_COUNTER_2_PRE);
+ __raw_writel(0, NC_VA_COUNTER_2_INI);
+ __raw_writel(0x2, NC_VA_COUNTER_2_CONTROL);
+}
+
+static int __init nc_timer_init(struct device_node *np)
+{
+ unsigned int irq;
+ unsigned int freq;
+
+ /* parse from devicetree */
+ timer_reg = (unsigned int) of_iomap(np, 0);
+ if (!timer_reg)
+ panic("%s, of_iomap err.\n", __func__);
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq)
+ panic("%s, irq_parse err.\n", __func__);
+
+ if (of_property_read_u32(np, "clock-frequency", &freq))
+ panic("%s, clock-frequency error.\n", __func__);
+
+ pr_info("Nationalchip Timer Init, reg: %x, irq: %d, freq: %d.\n",
+ timer_reg, irq, freq);
+
+ /* setup irq */
+ if (request_irq(irq, timer_interrupt, IRQF_TIMER, np->name, &nc_ced))
+ panic("%s timer_interrupt error.\n", __func__);
+
+ /* register */
+ clockevents_config_and_register(&nc_ced, freq, 1, ULONG_MAX);
+
+ nc_csd_enable();
+ clocksource_mmio_init(NC_VA_COUNTER_2_VALUE, "nationalchip-clksource", freq, 200, 32, clocksource_mmio_readl_up);
+
+ sched_clock_register(nc_sched_clock_read, 32, freq);
+
+ return 0;
+}
+CLOCKSOURCE_OF_DECLARE(nc_timer, "nationalchip,timer-v1", nc_timer_init);
+
--
2.7.4