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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/clocksource/timer-digicolor.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clocksource/timer-digicolor.c')
-rw-r--r--drivers/clocksource/timer-digicolor.c204
1 files changed, 204 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-digicolor.c b/drivers/clocksource/timer-digicolor.c
new file mode 100644
index 000000000..559aa9608
--- /dev/null
+++ b/drivers/clocksource/timer-digicolor.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Conexant Digicolor timer driver
+ *
+ * Author: Baruch Siach <baruch@tkos.co.il>
+ *
+ * Copyright (C) 2014 Paradox Innovation Ltd.
+ *
+ * Based on:
+ * Allwinner SoCs hstimer driver
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+/*
+ * Conexant Digicolor SoCs have 8 configurable timers, named from "Timer A" to
+ * "Timer H". Timer A is the only one with watchdog support, so it is dedicated
+ * to the watchdog driver. This driver uses Timer B for sched_clock(), and
+ * Timer C for clockevents.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched/clock.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+enum {
+ TIMER_A,
+ TIMER_B,
+ TIMER_C,
+ TIMER_D,
+ TIMER_E,
+ TIMER_F,
+ TIMER_G,
+ TIMER_H,
+};
+
+#define CONTROL(t) ((t)*8)
+#define COUNT(t) ((t)*8 + 4)
+
+#define CONTROL_DISABLE 0
+#define CONTROL_ENABLE BIT(0)
+#define CONTROL_MODE(m) ((m) << 4)
+#define CONTROL_MODE_ONESHOT CONTROL_MODE(1)
+#define CONTROL_MODE_PERIODIC CONTROL_MODE(2)
+
+struct digicolor_timer {
+ struct clock_event_device ce;
+ void __iomem *base;
+ u32 ticks_per_jiffy;
+ int timer_id; /* one of TIMER_* */
+};
+
+static struct digicolor_timer *dc_timer(struct clock_event_device *ce)
+{
+ return container_of(ce, struct digicolor_timer, ce);
+}
+
+static inline void dc_timer_disable(struct clock_event_device *ce)
+{
+ struct digicolor_timer *dt = dc_timer(ce);
+ writeb(CONTROL_DISABLE, dt->base + CONTROL(dt->timer_id));
+}
+
+static inline void dc_timer_enable(struct clock_event_device *ce, u32 mode)
+{
+ struct digicolor_timer *dt = dc_timer(ce);
+ writeb(CONTROL_ENABLE | mode, dt->base + CONTROL(dt->timer_id));
+}
+
+static inline void dc_timer_set_count(struct clock_event_device *ce,
+ unsigned long count)
+{
+ struct digicolor_timer *dt = dc_timer(ce);
+ writel(count, dt->base + COUNT(dt->timer_id));
+}
+
+static int digicolor_clkevt_shutdown(struct clock_event_device *ce)
+{
+ dc_timer_disable(ce);
+ return 0;
+}
+
+static int digicolor_clkevt_set_oneshot(struct clock_event_device *ce)
+{
+ dc_timer_disable(ce);
+ dc_timer_enable(ce, CONTROL_MODE_ONESHOT);
+ return 0;
+}
+
+static int digicolor_clkevt_set_periodic(struct clock_event_device *ce)
+{
+ struct digicolor_timer *dt = dc_timer(ce);
+
+ dc_timer_disable(ce);
+ dc_timer_set_count(ce, dt->ticks_per_jiffy);
+ dc_timer_enable(ce, CONTROL_MODE_PERIODIC);
+ return 0;
+}
+
+static int digicolor_clkevt_next_event(unsigned long evt,
+ struct clock_event_device *ce)
+{
+ dc_timer_disable(ce);
+ dc_timer_set_count(ce, evt);
+ dc_timer_enable(ce, CONTROL_MODE_ONESHOT);
+
+ return 0;
+}
+
+static struct digicolor_timer dc_timer_dev = {
+ .ce = {
+ .name = "digicolor_tick",
+ .rating = 340,
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = digicolor_clkevt_shutdown,
+ .set_state_periodic = digicolor_clkevt_set_periodic,
+ .set_state_oneshot = digicolor_clkevt_set_oneshot,
+ .tick_resume = digicolor_clkevt_shutdown,
+ .set_next_event = digicolor_clkevt_next_event,
+ },
+ .timer_id = TIMER_C,
+};
+
+static irqreturn_t digicolor_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static u64 notrace digicolor_timer_sched_read(void)
+{
+ return ~readl(dc_timer_dev.base + COUNT(TIMER_B));
+}
+
+static int __init digicolor_timer_init(struct device_node *node)
+{
+ unsigned long rate;
+ struct clk *clk;
+ int ret, irq;
+
+ /*
+ * timer registers are shared with the watchdog timer;
+ * don't map exclusively
+ */
+ dc_timer_dev.base = of_iomap(node, 0);
+ if (!dc_timer_dev.base) {
+ pr_err("Can't map registers\n");
+ return -ENXIO;
+ }
+
+ irq = irq_of_parse_and_map(node, dc_timer_dev.timer_id);
+ if (irq <= 0) {
+ pr_err("Can't parse IRQ\n");
+ return -EINVAL;
+ }
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ pr_err("Can't get timer clock\n");
+ return PTR_ERR(clk);
+ }
+ clk_prepare_enable(clk);
+ rate = clk_get_rate(clk);
+ dc_timer_dev.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+
+ writeb(CONTROL_DISABLE, dc_timer_dev.base + CONTROL(TIMER_B));
+ writel(UINT_MAX, dc_timer_dev.base + COUNT(TIMER_B));
+ writeb(CONTROL_ENABLE, dc_timer_dev.base + CONTROL(TIMER_B));
+
+ sched_clock_register(digicolor_timer_sched_read, 32, rate);
+ clocksource_mmio_init(dc_timer_dev.base + COUNT(TIMER_B), node->name,
+ rate, 340, 32, clocksource_mmio_readl_down);
+
+ ret = request_irq(irq, digicolor_timer_interrupt,
+ IRQF_TIMER | IRQF_IRQPOLL, "digicolor_timerC",
+ &dc_timer_dev.ce);
+ if (ret) {
+ pr_warn("request of timer irq %d failed (%d)\n", irq, ret);
+ return ret;
+ }
+
+ dc_timer_dev.ce.cpumask = cpu_possible_mask;
+ dc_timer_dev.ce.irq = irq;
+
+ clockevents_config_and_register(&dc_timer_dev.ce, rate, 0, 0xffffffff);
+
+ return 0;
+}
+TIMER_OF_DECLARE(conexant_digicolor, "cnxt,cx92755-timer",
+ digicolor_timer_init);