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>

arch/nios2/cpu/Makefile

@@ -7,5 +7,5 @@
 
 extra-y	= start.o
 obj-y	= exceptions.o
-obj-y	+= cpu.o interrupts.o sysid.o timer.o traps.o
+obj-y	+= cpu.o interrupts.o sysid.o traps.o
 obj-y	+= fdt.o

arch/nios2/cpu/timer.c

@@ -1,65 +0,0 @@
-/*
- * (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 <asm/nios2.h>
-#include <asm/types.h>
-#include <asm/io.h>
-
-struct nios_timer {
-	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 */
-};
-
-/* status register */
-#define NIOS_TIMER_TO		(1 << 0)	/* Timeout */
-#define NIOS_TIMER_RUN		(1 << 1)	/* Timer running */
-
-/* control register */
-#define NIOS_TIMER_ITO		(1 << 0)	/* Timeout interrupt enable */
-#define NIOS_TIMER_CONT		(1 << 1)	/* Continuous mode */
-#define NIOS_TIMER_START	(1 << 2)	/* Start timer */
-#define NIOS_TIMER_STOP		(1 << 3)	/* Stop timer */
-
-/*************************************************************************/
-unsigned long notrace timer_read_counter(void)
-{
-	struct nios_timer *tmr = (struct nios_timer *)CONFIG_SYS_TIMER_BASE;
-	u32 val;
-
-	/* Trigger update */
-	writel(0x0, &tmr->snapl);
-
-	/* Read timer value */
-	val = readl(&tmr->snapl) & 0xffff;
-	val |= (readl(&tmr->snaph) & 0xffff) << 16;
-
-	return ~val;
-}
-
-int timer_init(void)
-{
-	struct nios_timer *tmr = (struct nios_timer *)CONFIG_SYS_TIMER_BASE;
-
-	writel(0, &tmr->status);
-	writel(0, &tmr->control);
-	writel(NIOS_TIMER_STOP, &tmr->control);
-
-	writel(0xffff, &tmr->periodl);
-	writel(0xffff, &tmr->periodh);
-
-	writel(NIOS_TIMER_CONT | NIOS_TIMER_START, &tmr->control);
-
-	return 0;
-}

common/board_f.c

@@ -795,8 +795,7 @@ static init_fnc_t init_sequence_f[] = {
 	init_timebase,
 #endif
 #if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || \
-		defined(CONFIG_BLACKFIN) || defined(CONFIG_NDS32) || \
-		defined(CONFIG_NIOS2)
+		defined(CONFIG_BLACKFIN) || defined(CONFIG_NDS32)
 	timer_init,		/* initialize timer */
 #endif
 #ifdef CONFIG_SYS_ALLOC_DPRAM

configs/nios2-generic_defconfig

@@ -18,3 +18,5 @@ CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_ALTERA_PIO=y
 CONFIG_ALTERA_JTAG_UART=y
 CONFIG_ALTERA_JTAG_UART_BYPASS=y
+CONFIG_TIMER=y
+CONFIG_ALTERA_TIMER=y

doc/device-tree-bindings/timer/altera_timer.txt

@@ -0,0 +1,19 @@
+Altera Timer
+
+Required properties:
+
+- compatible : should be "altr,timer-1.0"
+- reg : Specifies base physical address and size of the registers.
+- interrupt-parent: phandle of the interrupt controller
+- interrupts : Should contain the timer interrupt number
+- clock-frequency : The frequency of the clock that drives the counter, in Hz.
+
+Example:
+
+timer {
+	compatible = "altr,timer-1.0";
+	reg = <0x00400000 0x00000020>;
+	interrupt-parent = <&cpu>;
+	interrupts = <11>;
+	clock-frequency = <125000000>;
+};

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

drivers/timer/Makefile

@@ -5,3 +5,4 @@
 #
 
 obj-$(CONFIG_TIMER)		+= timer-uclass.o
+obj-$(CONFIG_ALTERA_TIMER)	+= altera_timer.o

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,
+};

include/configs/nios2-generic.h

@@ -26,11 +26,6 @@
 #define CONFIG_SYS_CONSOLE_INFO_QUIET	/* Suppress console info */
 
 /*
- * TIMER
- */
-#define CONFIG_SYS_TIMER_RATE		CONFIG_SYS_TIMER_FREQ
-
-/*
  * BOOTP options
  */
 #define CONFIG_BOOTP_BOOTFILESIZE