[PATCH RFC 08/20] timer: Add Ingenic JZ4730 timer driver

[Lubomir Rintel <lkundrak@v3.sk>]

This adds support for a timer block on JZ4730 SoC.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
---
 drivers/timer/Kconfig        |  8 ++++
 drivers/timer/Makefile       |  1 +
 drivers/timer/jz4730_timer.c | 83 ++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 drivers/timer/jz4730_timer.c

diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig
index 80743a25519..9d5a84c03ea 100644
--- a/drivers/timer/Kconfig
+++ b/drivers/timer/Kconfig
@@ -110,6 +110,14 @@ config DESIGNWARE_APB_TIMER
 	  Enables support for the Designware APB Timer driver. This timer is
 	  present on Altera SoCFPGA SoCs.
 
+config JZ4730_TIMER
+	bool "Ingenic JZ4730 timer support"
+	depends on TIMER
+	default y if SOC_JZ4730
+	help
+	  Select this to enable support for the timer found on
+	  devices based on the Ingenic JZ4730 SoC.
+
 config MPC83XX_TIMER
 	bool "MPC83xx timer support"
 	depends on TIMER
diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile
index eb5c48cc6ce..67529c78e59 100644
--- a/drivers/timer/Makefile
+++ b/drivers/timer/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_ATCPIT100_TIMER) += atcpit100_timer.o
 obj-$(CONFIG_ATMEL_PIT_TIMER) += atmel_pit_timer.o
 obj-$(CONFIG_CADENCE_TTC_TIMER)	+= cadence-ttc.o
 obj-$(CONFIG_DESIGNWARE_APB_TIMER)	+= dw-apb-timer.o
+obj-$(CONFIG_JZ4730_TIMER) += jz4730_timer.o
 obj-$(CONFIG_MPC83XX_TIMER) += mpc83xx_timer.o
 obj-$(CONFIG_NOMADIK_MTU_TIMER)	+= nomadik-mtu-timer.o
 obj-$(CONFIG_OMAP_TIMER)	+= omap-timer.o
diff --git a/drivers/timer/jz4730_timer.c b/drivers/timer/jz4730_timer.c
new file mode 100644
index 00000000000..d2c77a20993
--- /dev/null
+++ b/drivers/timer/jz4730_timer.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * JZ4730 Timer driver.
+ *
+ * Copyright (c) 2020 Lubomir Rintel <lkundrak@v3.sk>
+ */
+
+#include <common.h>
+#include <config.h>
+#include <clk.h>
+#include <dm.h>
+#include <timer.h>
+#include <time.h>
+#include <asm/global_data.h>
+#include <asm/io.h>
+#include <linux/bitops.h>
+
+#define CHANNEL_ID  0
+
+#define OST_TER		(0x00)
+#define OST_TRDR(n)	(0x10 + ((n) * 0x20))
+#define OST_TCNT(n)	(0x14 + ((n) * 0x20))
+#define OST_TCSR(n)	(0x18 + ((n) * 0x20))
+#define OST_TCRB(n)	(0x1c + ((n) * 0x20))
+
+#define OST_TCSR_CKS_PCLK_256	0x0003
+
+struct jz4730_timer_priv {
+	void __iomem *base;
+};
+
+static u64 jz4730_timer_get_count(struct udevice *dev)
+{
+	struct jz4730_timer_priv *priv = dev_get_priv(dev);
+	u32 val = readl(priv->base + OST_TCNT(CHANNEL_ID));
+
+	return timer_conv_64(U32_MAX - val);
+}
+
+static int jz4730_timer_probe(struct udevice *dev)
+{
+	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct jz4730_timer_priv *priv = dev_get_priv(dev);
+	struct clk clk;
+	int ret;
+
+	priv->base = dev_remap_addr(dev);
+	if (!priv->base)
+		return -EINVAL;
+
+	ret = clk_get_by_name(dev, "pclk", &clk);
+	if (ret)
+		return ret;
+
+	uc_priv->clock_rate = clk_get_rate(&clk);
+	uc_priv->clock_rate /= 256;
+
+	writew(OST_TCSR_CKS_PCLK_256, priv->base + OST_TCSR(CHANNEL_ID));
+	writel(U32_MAX, priv->base + OST_TRDR(CHANNEL_ID));
+	writel(U32_MAX, priv->base + OST_TCNT(CHANNEL_ID));
+	writeb(BIT(CHANNEL_ID), priv->base + OST_TER);
+
+	return 0;
+}
+
+static const struct timer_ops jz4730_timer_ops = {
+	.get_count = jz4730_timer_get_count,
+};
+
+static const struct udevice_id jz4730_timer_ids[] = {
+	{ .compatible = "ingenic,jz4730-tcu" },
+	{ }
+};
+
+U_BOOT_DRIVER(jz4730_timer) = {
+	.name = "jz4730_timer",
+	.id = UCLASS_TIMER,
+	.of_match = jz4730_timer_ids,
+	.priv_auto_alloc_size = sizeof(struct jz4730_timer_priv),
+	.probe = jz4730_timer_probe,
+	.ops = &jz4730_timer_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
-- 
2.28.0