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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 19:41:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 19:41:08 -0700
commitc9297d284126b80c9cfd72c690e0da531c99fc48 (patch)
treebec7ce343f2a37def4e99ec556deb3998dbeb041 /drivers/clocksource/timer-atcpit100.c
parent17e3cd222af1c72a750cd83565bb8dfc7bc12335 (diff)
parent6fc61ee69433e7e0433cabd36f78bb5fb3b26524 (diff)
Merge tag 'nds32-for-linus-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux
Pull nds32 architecture support from Greentime Hu: "This contains the core nds32 Linux port (including interrupt controller driver and timer driver), which has been through seven rounds of review on mailing list. It is able to boot to shell and passes most LTP-2017 testsuites in nds32 AE3XX platform: Total Tests: 1901 Total Skipped Tests: 618 Total Failures: 78" Reviewed-by: Arnd Bergmann <arnd@arndb.de> * tag 'nds32-for-linus-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux: (44 commits) nds32: To use the generic dump_stack() nds32: fix building failed if using elf toolchain. nios2: add ioremap_nocache declaration before include asm-generic/io.h. nds32: fix building failed if using older version gcc. dt-bindings: timer: Add andestech atcpit100 timer binding doc clocksource/drivers/atcpit100: VDSO support clocksource/drivers/atcpit100: Add andestech atcpit100 timer net: faraday add nds32 support. irqchip: Andestech Internal Vector Interrupt Controller driver dt-bindings: interrupt-controller: Andestech Internal Vector Interrupt Controller dt-bindings: nds32 SoC Bindings dt-bindings: nds32 L2 cache controller Bindings dt-bindings: nds32 CPU Bindings MAINTAINERS: Add nds32 nds32: Build infrastructure nds32: defconfig nds32: Miscellaneous header files nds32: Device tree support nds32: Generic timers support nds32: Loadable modules ...
Diffstat (limited to 'drivers/clocksource/timer-atcpit100.c')
-rw-r--r--drivers/clocksource/timer-atcpit100.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-atcpit100.c b/drivers/clocksource/timer-atcpit100.c
new file mode 100644
index 000000000000..5e23d7b4a722
--- /dev/null
+++ b/drivers/clocksource/timer-atcpit100.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+/*
+ * Andestech ATCPIT100 Timer Device Driver Implementation
+ * Rick Chen, Andes Technology Corporation <rick@andestech.com>
+ *
+ */
+
+#include <linux/irq.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/cpufreq.h>
+#include <linux/sched.h>
+#include <linux/sched_clock.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include "timer-of.h"
+#ifdef CONFIG_NDS32
+#include <asm/vdso_timer_info.h>
+#endif
+
+/*
+ * Definition of register offsets
+ */
+
+/* ID and Revision Register */
+#define ID_REV 0x0
+
+/* Configuration Register */
+#define CFG 0x10
+
+/* Interrupt Enable Register */
+#define INT_EN 0x14
+#define CH_INT_EN(c, i) ((1<<i)<<(4*c))
+#define CH0INT0EN 0x01
+
+/* Interrupt Status Register */
+#define INT_STA 0x18
+#define CH0INT0 0x01
+
+/* Channel Enable Register */
+#define CH_EN 0x1C
+#define CH0TMR0EN 0x1
+#define CH1TMR0EN 0x10
+
+/* Channel 0 , 1 Control Register */
+#define CH0_CTL (0x20)
+#define CH1_CTL (0x20 + 0x10)
+
+/* Channel clock source , bit 3 , 0:External clock , 1:APB clock */
+#define APB_CLK BIT(3)
+
+/* Channel mode , bit 0~2 */
+#define TMR_32 0x1
+#define TMR_16 0x2
+#define TMR_8 0x3
+
+/* Channel 0 , 1 Reload Register */
+#define CH0_REL (0x24)
+#define CH1_REL (0x24 + 0x10)
+
+/* Channel 0 , 1 Counter Register */
+#define CH0_CNT (0x28)
+#define CH1_CNT (0x28 + 0x10)
+
+#define TIMER_SYNC_TICKS 3
+
+static void atcpit100_ch1_tmr0_en(void __iomem *base)
+{
+ writel(~0, base + CH1_REL);
+ writel(APB_CLK|TMR_32, base + CH1_CTL);
+}
+
+static void atcpit100_ch0_tmr0_en(void __iomem *base)
+{
+ writel(APB_CLK|TMR_32, base + CH0_CTL);
+}
+
+static void atcpit100_clkevt_time_setup(void __iomem *base, unsigned long delay)
+{
+ writel(delay, base + CH0_CNT);
+ writel(delay, base + CH0_REL);
+}
+
+static void atcpit100_timer_clear_interrupt(void __iomem *base)
+{
+ u32 val;
+
+ val = readl(base + INT_STA);
+ writel(val | CH0INT0, base + INT_STA);
+}
+
+static void atcpit100_clocksource_start(void __iomem *base)
+{
+ u32 val;
+
+ val = readl(base + CH_EN);
+ writel(val | CH1TMR0EN, base + CH_EN);
+}
+
+static void atcpit100_clkevt_time_start(void __iomem *base)
+{
+ u32 val;
+
+ val = readl(base + CH_EN);
+ writel(val | CH0TMR0EN, base + CH_EN);
+}
+
+static void atcpit100_clkevt_time_stop(void __iomem *base)
+{
+ u32 val;
+
+ atcpit100_timer_clear_interrupt(base);
+ val = readl(base + CH_EN);
+ writel(val & ~CH0TMR0EN, base + CH_EN);
+}
+
+static int atcpit100_clkevt_next_event(unsigned long evt,
+ struct clock_event_device *clkevt)
+{
+ u32 val;
+ struct timer_of *to = to_timer_of(clkevt);
+
+ val = readl(timer_of_base(to) + CH_EN);
+ writel(val & ~CH0TMR0EN, timer_of_base(to) + CH_EN);
+ writel(evt, timer_of_base(to) + CH0_REL);
+ writel(val | CH0TMR0EN, timer_of_base(to) + CH_EN);
+
+ return 0;
+}
+
+static int atcpit100_clkevt_set_periodic(struct clock_event_device *evt)
+{
+ struct timer_of *to = to_timer_of(evt);
+
+ atcpit100_clkevt_time_setup(timer_of_base(to), timer_of_period(to));
+ atcpit100_clkevt_time_start(timer_of_base(to));
+
+ return 0;
+}
+static int atcpit100_clkevt_shutdown(struct clock_event_device *evt)
+{
+ struct timer_of *to = to_timer_of(evt);
+
+ atcpit100_clkevt_time_stop(timer_of_base(to));
+
+ return 0;
+}
+static int atcpit100_clkevt_set_oneshot(struct clock_event_device *evt)
+{
+ struct timer_of *to = to_timer_of(evt);
+ u32 val;
+
+ writel(~0x0, timer_of_base(to) + CH0_REL);
+ val = readl(timer_of_base(to) + CH_EN);
+ writel(val | CH0TMR0EN, timer_of_base(to) + CH_EN);
+
+ return 0;
+}
+
+static irqreturn_t atcpit100_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+ struct timer_of *to = to_timer_of(evt);
+
+ atcpit100_timer_clear_interrupt(timer_of_base(to));
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct timer_of to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE,
+
+ .clkevt = {
+ .name = "atcpit100_tick",
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = atcpit100_clkevt_shutdown,
+ .set_state_periodic = atcpit100_clkevt_set_periodic,
+ .set_state_oneshot = atcpit100_clkevt_set_oneshot,
+ .tick_resume = atcpit100_clkevt_shutdown,
+ .set_next_event = atcpit100_clkevt_next_event,
+ .cpumask = cpu_all_mask,
+ },
+
+ .of_irq = {
+ .handler = atcpit100_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ },
+
+ /*
+ * FIXME: we currently only support clocking using PCLK
+ * and using EXTCLK is not supported in the driver.
+ */
+ .of_clk = {
+ .name = "PCLK",
+ }
+};
+
+static u64 notrace atcpit100_timer_sched_read(void)
+{
+ return ~readl(timer_of_base(&to) + CH1_CNT);
+}
+
+#ifdef CONFIG_NDS32
+static void fill_vdso_need_info(struct device_node *node)
+{
+ struct resource timer_res;
+ of_address_to_resource(node, 0, &timer_res);
+ timer_info.mapping_base = (unsigned long)timer_res.start;
+ timer_info.cycle_count_down = true;
+ timer_info.cycle_count_reg_offset = CH1_CNT;
+}
+#endif
+
+static int __init atcpit100_timer_init(struct device_node *node)
+{
+ int ret;
+ u32 val;
+ void __iomem *base;
+
+ ret = timer_of_init(node, &to);
+ if (ret)
+ return ret;
+
+ base = timer_of_base(&to);
+
+ sched_clock_register(atcpit100_timer_sched_read, 32,
+ timer_of_rate(&to));
+
+ ret = clocksource_mmio_init(base + CH1_CNT,
+ node->name, timer_of_rate(&to), 300, 32,
+ clocksource_mmio_readl_down);
+
+ if (ret) {
+ pr_err("Failed to register clocksource\n");
+ return ret;
+ }
+
+ /* clear channel 0 timer0 interrupt */
+ atcpit100_timer_clear_interrupt(base);
+
+ clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+ TIMER_SYNC_TICKS, 0xffffffff);
+ atcpit100_ch0_tmr0_en(base);
+ atcpit100_ch1_tmr0_en(base);
+ atcpit100_clocksource_start(base);
+ atcpit100_clkevt_time_start(base);
+
+ /* Enable channel 0 timer0 interrupt */
+ val = readl(base + INT_EN);
+ writel(val | CH0INT0EN, base + INT_EN);
+
+#ifdef CONFIG_NDS32
+ fill_vdso_need_info(node);
+#endif
+
+ return ret;
+}
+
+TIMER_OF_DECLARE(atcpit100, "andestech,atcpit100", atcpit100_timer_init);