Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 273 insertions, 0 deletions

diff --git a/drivers/clocksource/mxs_timer.c b/drivers/clocksource/mxs_timer.c
new file mode 100644
index 000000000..e52e12d27
--- /dev/null
+++ b/drivers/clocksource/mxs_timer.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+//  Copyright (C) 2000-2001 Deep Blue Solutions
+//  Copyright (C) 2002 Shane Nay (shane@minirl.com)
+//  Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com)
+//  Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de)
+//  Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/stmp_device.h>
+#include <linux/sched_clock.h>
+
+/*
+ * There are 2 versions of the timrot on Freescale MXS-based SoCs.
+ * The v1 on MX23 only gets 16 bits counter, while v2 on MX28
+ * extends the counter to 32 bits.
+ *
+ * The implementation uses two timers, one for clock_event and
+ * another for clocksource. MX28 uses timrot 0 and 1, while MX23
+ * uses 0 and 2.
+ */
+
+#define MX23_TIMROT_VERSION_OFFSET	0x0a0
+#define MX28_TIMROT_VERSION_OFFSET	0x120
+#define BP_TIMROT_MAJOR_VERSION		24
+#define BV_TIMROT_VERSION_1		0x01
+#define BV_TIMROT_VERSION_2		0x02
+#define timrot_is_v1()	(timrot_major_version == BV_TIMROT_VERSION_1)
+
+/*
+ * There are 4 registers for each timrotv2 instance, and 2 registers
+ * for each timrotv1. So address step 0x40 in macros below strides
+ * one instance of timrotv2 while two instances of timrotv1.
+ *
+ * As the result, HW_TIMROT_XXXn(1) defines the address of timrot1
+ * on MX28 while timrot2 on MX23.
+ */
+/* common between v1 and v2 */
+#define HW_TIMROT_ROTCTRL		0x00
+#define HW_TIMROT_TIMCTRLn(n)		(0x20 + (n) * 0x40)
+/* v1 only */
+#define HW_TIMROT_TIMCOUNTn(n)		(0x30 + (n) * 0x40)
+/* v2 only */
+#define HW_TIMROT_RUNNING_COUNTn(n)	(0x30 + (n) * 0x40)
+#define HW_TIMROT_FIXED_COUNTn(n)	(0x40 + (n) * 0x40)
+
+#define BM_TIMROT_TIMCTRLn_RELOAD	(1 << 6)
+#define BM_TIMROT_TIMCTRLn_UPDATE	(1 << 7)
+#define BM_TIMROT_TIMCTRLn_IRQ_EN	(1 << 14)
+#define BM_TIMROT_TIMCTRLn_IRQ		(1 << 15)
+#define BP_TIMROT_TIMCTRLn_SELECT	0
+#define BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL		0x8
+#define BV_TIMROTv2_TIMCTRLn_SELECT__32KHZ_XTAL		0xb
+#define BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS	0xf
+
+static struct clock_event_device mxs_clockevent_device;
+
+static void __iomem *mxs_timrot_base;
+static u32 timrot_major_version;
+
+static inline void timrot_irq_disable(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static inline void timrot_irq_enable(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_SET);
+}
+
+static void timrot_irq_acknowledge(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static u64 timrotv1_get_cycles(struct clocksource *cs)
+{
+	return ~((__raw_readl(mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1))
+			& 0xffff0000) >> 16);
+}
+
+static int timrotv1_set_next_event(unsigned long evt,
+					struct clock_event_device *dev)
+{
+	/* timrot decrements the count */
+	__raw_writel(evt, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(0));
+
+	return 0;
+}
+
+static int timrotv2_set_next_event(unsigned long evt,
+					struct clock_event_device *dev)
+{
+	/* timrot decrements the count */
+	__raw_writel(evt, mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(0));
+
+	return 0;
+}
+
+static irqreturn_t mxs_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	timrot_irq_acknowledge();
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static void mxs_irq_clear(char *state)
+{
+	/* Disable interrupt in timer module */
+	timrot_irq_disable();
+
+	/* Set event time into the furthest future */
+	if (timrot_is_v1())
+		__raw_writel(0xffff, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+	else
+		__raw_writel(0xffffffff,
+			     mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+	/* Clear pending interrupt */
+	timrot_irq_acknowledge();
+	pr_debug("%s: changing mode to %s\n", __func__, state);
+}
+
+static int mxs_shutdown(struct clock_event_device *evt)
+{
+	mxs_irq_clear("shutdown");
+
+	return 0;
+}
+
+static int mxs_set_oneshot(struct clock_event_device *evt)
+{
+	if (clockevent_state_oneshot(evt))
+		mxs_irq_clear("oneshot");
+	timrot_irq_enable();
+	return 0;
+}
+
+static struct clock_event_device mxs_clockevent_device = {
+	.name			= "mxs_timrot",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown	= mxs_shutdown,
+	.set_state_oneshot	= mxs_set_oneshot,
+	.tick_resume		= mxs_shutdown,
+	.set_next_event		= timrotv2_set_next_event,
+	.rating			= 200,
+};
+
+static int __init mxs_clockevent_init(struct clk *timer_clk)
+{
+	if (timrot_is_v1())
+		mxs_clockevent_device.set_next_event = timrotv1_set_next_event;
+	mxs_clockevent_device.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&mxs_clockevent_device,
+					clk_get_rate(timer_clk),
+					timrot_is_v1() ? 0xf : 0x2,
+					timrot_is_v1() ? 0xfffe : 0xfffffffe);
+
+	return 0;
+}
+
+static struct clocksource clocksource_mxs = {
+	.name		= "mxs_timer",
+	.rating		= 200,
+	.read		= timrotv1_get_cycles,
+	.mask		= CLOCKSOURCE_MASK(16),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static u64 notrace mxs_read_sched_clock_v2(void)
+{
+	return ~readl_relaxed(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1));
+}
+
+static int __init mxs_clocksource_init(struct clk *timer_clk)
+{
+	unsigned int c = clk_get_rate(timer_clk);
+
+	if (timrot_is_v1())
+		clocksource_register_hz(&clocksource_mxs, c);
+	else {
+		clocksource_mmio_init(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1),
+			"mxs_timer", c, 200, 32, clocksource_mmio_readl_down);
+		sched_clock_register(mxs_read_sched_clock_v2, 32, c);
+	}
+
+	return 0;
+}
+
+static int __init mxs_timer_init(struct device_node *np)
+{
+	struct clk *timer_clk;
+	int irq, ret;
+
+	mxs_timrot_base = of_iomap(np, 0);
+	WARN_ON(!mxs_timrot_base);
+
+	timer_clk = of_clk_get(np, 0);
+	if (IS_ERR(timer_clk)) {
+		pr_err("%s: failed to get clk\n", __func__);
+		return PTR_ERR(timer_clk);
+	}
+
+	ret = clk_prepare_enable(timer_clk);
+	if (ret)
+		return ret;
+
+	/*
+	 * Initialize timers to a known state
+	 */
+	stmp_reset_block(mxs_timrot_base + HW_TIMROT_ROTCTRL);
+
+	/* get timrot version */
+	timrot_major_version = __raw_readl(mxs_timrot_base +
+			(of_device_is_compatible(np, "fsl,imx23-timrot") ?
+						MX23_TIMROT_VERSION_OFFSET :
+						MX28_TIMROT_VERSION_OFFSET));
+	timrot_major_version >>= BP_TIMROT_MAJOR_VERSION;
+
+	/* one for clock_event */
+	__raw_writel((timrot_is_v1() ?
+			BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+			BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+			BM_TIMROT_TIMCTRLn_UPDATE |
+			BM_TIMROT_TIMCTRLn_IRQ_EN,
+			mxs_timrot_base + HW_TIMROT_TIMCTRLn(0));
+
+	/* another for clocksource */
+	__raw_writel((timrot_is_v1() ?
+			BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+			BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+			BM_TIMROT_TIMCTRLn_RELOAD,
+			mxs_timrot_base + HW_TIMROT_TIMCTRLn(1));
+
+	/* set clocksource timer fixed count to the maximum */
+	if (timrot_is_v1())
+		__raw_writel(0xffff,
+			mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+	else
+		__raw_writel(0xffffffff,
+			mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+	/* init and register the timer to the framework */
+	ret = mxs_clocksource_init(timer_clk);
+	if (ret)
+		return ret;
+
+	ret = mxs_clockevent_init(timer_clk);
+	if (ret)
+		return ret;
+
+	/* Make irqs happen */
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	return request_irq(irq, mxs_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			   "MXS Timer Tick", &mxs_clockevent_device);
+}
+TIMER_OF_DECLARE(mxs, "fsl,timrot", mxs_timer_init);