nios2: convert altera timer to driver model

Convert altera timer to driver model.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Chin Liang See <clsee@altera.com>

3 files changed, 112 insertions, 0 deletions

diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig
index 8e8d600..97c4128 100644
--- a/drivers/timer/Kconfig
+++ b/drivers/timer/Kconfig
@@ -9,4 +9,11 @@ config TIMER
 	  will be used. The timer is usually a 32 bits free-running up
 	  counter. There may be no real tick, and no timer interrupt.
 
+config ALTERA_TIMER
+	bool "Altera Timer support"
+	depends on TIMER
+	help
+	  Select this to enable an timer for Altera devices. Please find
+	  details on the "Embedded Peripherals IP User Guide" of Altera.
+
 endmenu
diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile
index afb0009..ae66c07 100644
--- a/drivers/timer/Makefile
+++ b/drivers/timer/Makefile
@@ -5,3 +5,4 @@
 #
 
 obj-$(CONFIG_TIMER)		+= timer-uclass.o
+obj-$(CONFIG_ALTERA_TIMER)	+= altera_timer.o
diff --git a/drivers/timer/altera_timer.c b/drivers/timer/altera_timer.c
new file mode 100644
index 0000000..2ef9ad6
--- /dev/null
+++ b/drivers/timer/altera_timer.c
@@ -0,0 +1,104 @@
+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <timer.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct altera_timer_regs {
+	u32	status;		/* Timer status reg */
+	u32	control;	/* Timer control reg */
+	u32	periodl;	/* Timeout period low */
+	u32	periodh;	/* Timeout period high */
+	u32	snapl;		/* Snapshot low */
+	u32	snaph;		/* Snapshot high */
+};
+
+struct altera_timer_platdata {
+	struct altera_timer_regs *regs;
+	unsigned long clock_rate;
+};
+
+/* control register */
+#define ALTERA_TIMER_CONT	(1 << 1)	/* Continuous mode */
+#define ALTERA_TIMER_START	(1 << 2)	/* Start timer */
+#define ALTERA_TIMER_STOP	(1 << 3)	/* Stop timer */
+
+static int altera_timer_get_count(struct udevice *dev, unsigned long *count)
+{
+	struct altera_timer_platdata *plat = dev->platdata;
+	struct altera_timer_regs *const regs = plat->regs;
+	u32 val;
+
+	/* Trigger update */
+	writel(0x0, &regs->snapl);
+
+	/* Read timer value */
+	val = readl(&regs->snapl) & 0xffff;
+	val |= (readl(&regs->snaph) & 0xffff) << 16;
+	*count = ~val;
+
+	return 0;
+}
+
+static int altera_timer_probe(struct udevice *dev)
+{
+	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct altera_timer_platdata *plat = dev->platdata;
+	struct altera_timer_regs *const regs = plat->regs;
+
+	uc_priv->clock_rate = plat->clock_rate;
+
+	writel(0, &regs->status);
+	writel(0, &regs->control);
+	writel(ALTERA_TIMER_STOP, &regs->control);
+
+	writel(0xffff, &regs->periodl);
+	writel(0xffff, &regs->periodh);
+	writel(ALTERA_TIMER_CONT | ALTERA_TIMER_START, &regs->control);
+
+	return 0;
+}
+
+static int altera_timer_ofdata_to_platdata(struct udevice *dev)
+{
+	struct altera_timer_platdata *plat = dev_get_platdata(dev);
+
+	plat->regs = ioremap(dev_get_addr(dev),
+		sizeof(struct altera_timer_regs));
+	plat->clock_rate = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+		"clock-frequency", 0);
+
+	return 0;
+}
+
+static const struct timer_ops altera_timer_ops = {
+	.get_count = altera_timer_get_count,
+};
+
+static const struct udevice_id altera_timer_ids[] = {
+	{ .compatible = "altr,timer-1.0", },
+	{ }
+};
+
+U_BOOT_DRIVER(altera_timer) = {
+	.name	= "altera_timer",
+	.id	= UCLASS_TIMER,
+	.of_match = altera_timer_ids,
+	.ofdata_to_platdata = altera_timer_ofdata_to_platdata,
+	.platdata_auto_alloc_size = sizeof(struct altera_timer_platdata),
+	.probe = altera_timer_probe,
+	.ops	= &altera_timer_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};