timer: add orion-timer support

Add timer support for Kirkwood and MVEBU devices.

Cc: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/timer/orion-timer.c b/drivers/timer/orion-timer.c
new file mode 100644
index 0000000..fd30e1b
--- /dev/null
+++ b/drivers/timer/orion-timer.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <asm/io.h>
+#include <common.h>
+#include <dm/device.h>
+#include <dm/fdtaddr.h>
+#include <timer.h>
+
+#define TIMER_CTRL		0x00
+#define TIMER0_EN		BIT(0)
+#define TIMER0_RELOAD_EN	BIT(1)
+#define TIMER0_RELOAD		0x10
+#define TIMER0_VAL		0x14
+
+struct orion_timer_priv {
+	void *base;
+};
+
+static uint64_t orion_timer_get_count(struct udevice *dev)
+{
+	struct orion_timer_priv *priv = dev_get_priv(dev);
+
+	return ~readl(priv->base + TIMER0_VAL);
+}
+
+static int orion_timer_probe(struct udevice *dev)
+{
+	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct orion_timer_priv *priv = dev_get_priv(dev);
+
+	priv->base = devfdt_remap_addr_index(dev, 0);
+	if (!priv->base) {
+		debug("unable to map registers\n");
+		return -ENOMEM;
+	}
+
+	uc_priv->clock_rate = CONFIG_SYS_TCLK;
+
+	writel(~0, priv->base + TIMER0_VAL);
+	writel(~0, priv->base + TIMER0_RELOAD);
+
+	/* enable timer */
+	setbits_le32(priv->base + TIMER_CTRL, TIMER0_EN | TIMER0_RELOAD_EN);
+
+	return 0;
+}
+
+static const struct timer_ops orion_timer_ops = {
+	.get_count = orion_timer_get_count,
+};
+
+static const struct udevice_id orion_timer_ids[] = {
+	{ .compatible = "marvell,orion-timer" },
+	{}
+};
+
+U_BOOT_DRIVER(orion_timer) = {
+	.name	= "orion_timer",
+	.id	= UCLASS_TIMER,
+	.of_match = orion_timer_ids,
+	.probe = orion_timer_probe,
+	.ops	= &orion_timer_ops,
+	.priv_auto	= sizeof(struct orion_timer_priv),
+};