--- /dev/null
+=================
+gx6605s SOC Timer
+=================
+
+The timer is used in gx6605s soc as system timer and the driver
+contain clk event and clk source.
+
+==============================
+timer node bindings definition
+==============================
+
+ Description: Describes gx6605s SOC timer
+
+ PROPERTIES
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be "csky,gx6605s-timer"
+ - reg
+ Usage: required
+ Value type: <u32 u32>
+ Definition: <phyaddr size> in soc from cpu view
+ - clocks
+ Usage: required
+ Value type: phandle + clock specifier cells
+ Definition: must be input clk node
+ - interrupt
+ Usage: required
+ Value type: <u32>
+ Definition: must be timer irq num defined by soc
+
+Examples:
+---------
+
+ timer0: timer@20a000 {
+ compatible = "csky,gx6605s-timer";
+ reg = <0x0020a000 0x400>;
+ clocks = <&dummy_apb_clk>;
+ interrupts = <10>;
+ interrupt-parent = <&intc>;
+ };
--- /dev/null
+============================
+C-SKY Multi-processors Timer
+============================
+
+C-SKY multi-processors timer is designed for C-SKY SMP system and the
+regs is accessed by cpu co-processor 4 registers with mtcr/mfcr.
+
+ - PTIM_CTLR "cr<0, 14>" Control reg to start reset timer.
+ - PTIM_TSR "cr<1, 14>" Interrupt cleanup status reg.
+ - PTIM_CCVR "cr<3, 14>" Current counter value reg.
+ - PTIM_LVR "cr<6, 14>" Window value reg to triger next event.
+
+==============================
+timer node bindings definition
+==============================
+
+ Description: Describes SMP timer
+
+ PROPERTIES
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be "csky,mptimer"
+ - clocks
+ Usage: required
+ Value type: <node>
+ Definition: must be input clk node
+ - interrupts
+ Usage: required
+ Value type: <u32>
+ Definition: must be timer irq num defined by soc
+
+Examples:
+---------
+
+ timer: timer {
+ compatible = "csky,mptimer";
+ clocks = <&dummy_apb_clk>;
+ interrupts = <16>;
+ interrupt-parent = <&intc>;
+ };
is accessed via both the SBI and the rdcycle instruction. This is
required for all RISC-V systems.
+config CSKY_MP_TIMER
+ bool "SMP Timer for the C-SKY platform" if COMPILE_TEST
+ depends on CSKY
+ select TIMER_OF
+ help
+ Say yes here to enable C-SKY SMP timer driver used for C-SKY SMP
+ system.
+ csky,mptimer is not only used in SMP system, it also could be used
+ single core system. It's not a mmio reg and it use mtcr/mfcr instruction.
+
+config GX6605S_TIMER
+ bool "Gx6605s SOC system timer driver" if COMPILE_TEST
+ depends on CSKY
+ select CLKSRC_MMIO
+ select TIMER_OF
+ help
+ This option enables support for gx6605s SOC's timer.
+
endmenu
obj-$(CONFIG_X86_NUMACHIP) += numachip.o
obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o
obj-$(CONFIG_RISCV_TIMER) += riscv_timer.o
+obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o
+obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+
+#include "timer-of.h"
+
+#define CLKSRC_OFFSET 0x40
+
+#define TIMER_STATUS 0x00
+#define TIMER_VALUE 0x04
+#define TIMER_CONTRL 0x10
+#define TIMER_CONFIG 0x20
+#define TIMER_DIV 0x24
+#define TIMER_INI 0x28
+
+#define GX6605S_STATUS_CLR BIT(0)
+#define GX6605S_CONTRL_RST BIT(0)
+#define GX6605S_CONTRL_START BIT(1)
+#define GX6605S_CONFIG_EN BIT(0)
+#define GX6605S_CONFIG_IRQ_EN BIT(1)
+
+static irqreturn_t gx6605s_timer_interrupt(int irq, void *dev)
+{
+ struct clock_event_device *ce = dev;
+ void __iomem *base = timer_of_base(to_timer_of(ce));
+
+ writel_relaxed(GX6605S_STATUS_CLR, base + TIMER_STATUS);
+
+ ce->event_handler(ce);
+
+ return IRQ_HANDLED;
+}
+
+static int gx6605s_timer_set_oneshot(struct clock_event_device *ce)
+{
+ void __iomem *base = timer_of_base(to_timer_of(ce));
+
+ /* reset and stop counter */
+ writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL);
+
+ /* enable with irq and start */
+ writel_relaxed(GX6605S_CONFIG_EN | GX6605S_CONFIG_IRQ_EN,
+ base + TIMER_CONFIG);
+
+ return 0;
+}
+
+static int gx6605s_timer_set_next_event(unsigned long delta,
+ struct clock_event_device *ce)
+{
+ void __iomem *base = timer_of_base(to_timer_of(ce));
+
+ /* use reset to pause timer */
+ writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL);
+
+ /* config next timeout value */
+ writel_relaxed(ULONG_MAX - delta, base + TIMER_INI);
+ writel_relaxed(GX6605S_CONTRL_START, base + TIMER_CONTRL);
+
+ return 0;
+}
+
+static int gx6605s_timer_shutdown(struct clock_event_device *ce)
+{
+ void __iomem *base = timer_of_base(to_timer_of(ce));
+
+ writel_relaxed(0, base + TIMER_CONTRL);
+ writel_relaxed(0, base + TIMER_CONFIG);
+
+ return 0;
+}
+
+static struct timer_of to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+ .clkevt = {
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_DYNIRQ |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = gx6605s_timer_shutdown,
+ .set_state_oneshot = gx6605s_timer_set_oneshot,
+ .set_next_event = gx6605s_timer_set_next_event,
+ .cpumask = cpu_possible_mask,
+ },
+ .of_irq = {
+ .handler = gx6605s_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ },
+};
+
+static u64 notrace gx6605s_sched_clock_read(void)
+{
+ void __iomem *base;
+
+ base = timer_of_base(&to) + CLKSRC_OFFSET;
+
+ return (u64)readl_relaxed(base + TIMER_VALUE);
+}
+
+static void gx6605s_clkevt_init(void __iomem *base)
+{
+ writel_relaxed(0, base + TIMER_DIV);
+ writel_relaxed(0, base + TIMER_CONFIG);
+
+ clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), 2,
+ ULONG_MAX);
+}
+
+static int gx6605s_clksrc_init(void __iomem *base)
+{
+ writel_relaxed(0, base + TIMER_DIV);
+ writel_relaxed(0, base + TIMER_INI);
+
+ writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL);
+
+ writel_relaxed(GX6605S_CONFIG_EN, base + TIMER_CONFIG);
+
+ writel_relaxed(GX6605S_CONTRL_START, base + TIMER_CONTRL);
+
+ sched_clock_register(gx6605s_sched_clock_read, 32, timer_of_rate(&to));
+
+ return clocksource_mmio_init(base + TIMER_VALUE, "gx6605s",
+ timer_of_rate(&to), 200, 32, clocksource_mmio_readl_up);
+}
+
+static int __init gx6605s_timer_init(struct device_node *np)
+{
+ int ret;
+
+ /*
+ * The timer driver is for nationalchip gx6605s SOC and there are two
+ * same timer in gx6605s. We use one for clkevt and another for clksrc.
+ *
+ * The timer is mmio map to access, so we need give mmio address in dts.
+ *
+ * It provides a 32bit countup timer and interrupt will be caused by
+ * count-overflow.
+ * So we need set-next-event by ULONG_MAX - delta in TIMER_INI reg.
+ *
+ * The counter at 0x0 offset is clock event.
+ * The counter at 0x40 offset is clock source.
+ * They are the same in hardware, just different used by driver.
+ */
+ ret = timer_of_init(np, &to);
+ if (ret)
+ return ret;
+
+ gx6605s_clkevt_init(timer_of_base(&to));
+
+ return gx6605s_clksrc_init(timer_of_base(&to) + CLKSRC_OFFSET);
+}
+TIMER_OF_DECLARE(csky_gx6605s_timer, "csky,gx6605s-timer", gx6605s_timer_init);
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/cpu.h>
+#include <linux/of_irq.h>
+#include <asm/reg_ops.h>
+
+#include "timer-of.h"
+
+#define PTIM_CCVR "cr<3, 14>"
+#define PTIM_CTLR "cr<0, 14>"
+#define PTIM_LVR "cr<6, 14>"
+#define PTIM_TSR "cr<1, 14>"
+
+static int csky_mptimer_irq;
+
+static int csky_mptimer_set_next_event(unsigned long delta,
+ struct clock_event_device *ce)
+{
+ mtcr(PTIM_LVR, delta);
+
+ return 0;
+}
+
+static int csky_mptimer_shutdown(struct clock_event_device *ce)
+{
+ mtcr(PTIM_CTLR, 0);
+
+ return 0;
+}
+
+static int csky_mptimer_oneshot(struct clock_event_device *ce)
+{
+ mtcr(PTIM_CTLR, 1);
+
+ return 0;
+}
+
+static int csky_mptimer_oneshot_stopped(struct clock_event_device *ce)
+{
+ mtcr(PTIM_CTLR, 0);
+
+ return 0;
+}
+
+static DEFINE_PER_CPU(struct timer_of, csky_to) = {
+ .flags = TIMER_OF_CLOCK,
+ .clkevt = {
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_PERCPU |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = csky_mptimer_shutdown,
+ .set_state_oneshot = csky_mptimer_oneshot,
+ .set_state_oneshot_stopped = csky_mptimer_oneshot_stopped,
+ .set_next_event = csky_mptimer_set_next_event,
+ },
+};
+
+static irqreturn_t csky_timer_interrupt(int irq, void *dev)
+{
+ struct timer_of *to = this_cpu_ptr(&csky_to);
+
+ mtcr(PTIM_TSR, 0);
+
+ to->clkevt.event_handler(&to->clkevt);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * clock event for percpu
+ */
+static int csky_mptimer_starting_cpu(unsigned int cpu)
+{
+ struct timer_of *to = per_cpu_ptr(&csky_to, cpu);
+
+ to->clkevt.cpumask = cpumask_of(cpu);
+
+ clockevents_config_and_register(&to->clkevt, timer_of_rate(to),
+ 2, ULONG_MAX);
+
+ enable_percpu_irq(csky_mptimer_irq, 0);
+
+ return 0;
+}
+
+static int csky_mptimer_dying_cpu(unsigned int cpu)
+{
+ disable_percpu_irq(csky_mptimer_irq);
+
+ return 0;
+}
+
+/*
+ * clock source
+ */
+static u64 sched_clock_read(void)
+{
+ return (u64)mfcr(PTIM_CCVR);
+}
+
+static u64 clksrc_read(struct clocksource *c)
+{
+ return (u64)mfcr(PTIM_CCVR);
+}
+
+struct clocksource csky_clocksource = {
+ .name = "csky",
+ .rating = 400,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .read = clksrc_read,
+};
+
+static int __init csky_mptimer_init(struct device_node *np)
+{
+ int ret, cpu, cpu_rollback;
+ struct timer_of *to = NULL;
+
+ /*
+ * Csky_mptimer is designed for C-SKY SMP multi-processors and
+ * every core has it's own private irq and regs for clkevt and
+ * clksrc.
+ *
+ * The regs is accessed by cpu instruction: mfcr/mtcr instead of
+ * mmio map style. So we needn't mmio-address in dts, but we still
+ * need to give clk and irq number.
+ *
+ * We use private irq for the mptimer and irq number is the same
+ * for every core. So we use request_percpu_irq() in timer_of_init.
+ */
+ csky_mptimer_irq = irq_of_parse_and_map(np, 0);
+ if (csky_mptimer_irq <= 0)
+ return -EINVAL;
+
+ ret = request_percpu_irq(csky_mptimer_irq, csky_timer_interrupt,
+ "csky_mp_timer", &csky_to);
+ if (ret)
+ return -EINVAL;
+
+ for_each_possible_cpu(cpu) {
+ to = per_cpu_ptr(&csky_to, cpu);
+ ret = timer_of_init(np, to);
+ if (ret)
+ goto rollback;
+ }
+
+ clocksource_register_hz(&csky_clocksource, timer_of_rate(to));
+ sched_clock_register(sched_clock_read, 32, timer_of_rate(to));
+
+ ret = cpuhp_setup_state(CPUHP_AP_CSKY_TIMER_STARTING,
+ "clockevents/csky/timer:starting",
+ csky_mptimer_starting_cpu,
+ csky_mptimer_dying_cpu);
+ if (ret)
+ return -EINVAL;
+
+ return 0;
+
+rollback:
+ for_each_possible_cpu(cpu_rollback) {
+ if (cpu_rollback == cpu)
+ break;
+
+ to = per_cpu_ptr(&csky_to, cpu_rollback);
+ timer_of_cleanup(to);
+ }
+ return -EINVAL;
+}
+TIMER_OF_DECLARE(csky_mptimer, "csky,mptimer", csky_mptimer_init);
CPUHP_AP_MIPS_GIC_TIMER_STARTING,
CPUHP_AP_ARC_TIMER_STARTING,
CPUHP_AP_RISCV_TIMER_STARTING,
+ CPUHP_AP_CSKY_TIMER_STARTING,
CPUHP_AP_KVM_STARTING,
CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
CPUHP_AP_KVM_ARM_VGIC_STARTING,
projects / linux-block.git / commitdiff