diff options
Diffstat (limited to 'roms/u-boot/arch/arm/mach-zynq/timer.c')
-rw-r--r-- | roms/u-boot/arch/arm/mach-zynq/timer.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/roms/u-boot/arch/arm/mach-zynq/timer.c b/roms/u-boot/arch/arm/mach-zynq/timer.c new file mode 100644 index 000000000..a51822a53 --- /dev/null +++ b/roms/u-boot/arch/arm/mach-zynq/timer.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2017 Weidmüller Interface GmbH & Co. KG + * Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com> + * + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2011-2017 Xilinx, Inc. All rights reserved. + * + * (C) Copyright 2008 + * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de> + * + * (C) Copyright 2004 + * Philippe Robin, ARM Ltd. <philippe.robin@arm.com> + * + * (C) Copyright 2002-2004 + * Gary Jennejohn, DENX Software Engineering, <gj@denx.de> + * + * (C) Copyright 2003 + * Texas Instruments <www.ti.com> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Marius Groeger <mgroeger@sysgo.de> + * + * (C) Copyright 2002 + * Sysgo Real-Time Solutions, GmbH <www.elinos.com> + * Alex Zuepke <azu@sysgo.de> + */ + +#include <clk.h> +#include <common.h> +#include <div64.h> +#include <dm.h> +#include <init.h> +#include <time.h> +#include <malloc.h> +#include <asm/global_data.h> +#include <asm/io.h> +#include <asm/arch/hardware.h> +#include <asm/arch/clk.h> + +DECLARE_GLOBAL_DATA_PTR; + +struct scu_timer { + u32 load; /* Timer Load Register */ + u32 counter; /* Timer Counter Register */ + u32 control; /* Timer Control Register */ +}; + +static struct scu_timer *timer_base = + (struct scu_timer *)ZYNQ_SCUTIMER_BASEADDR; + +#define SCUTIMER_CONTROL_PRESCALER_MASK 0x0000FF00 /* Prescaler */ +#define SCUTIMER_CONTROL_PRESCALER_SHIFT 8 +#define SCUTIMER_CONTROL_AUTO_RELOAD_MASK 0x00000002 /* Auto-reload */ +#define SCUTIMER_CONTROL_ENABLE_MASK 0x00000001 /* Timer enable */ + +#define TIMER_LOAD_VAL 0xFFFFFFFF +#define TIMER_PRESCALE 255 + +int timer_init(void) +{ + const u32 emask = SCUTIMER_CONTROL_AUTO_RELOAD_MASK | + (TIMER_PRESCALE << SCUTIMER_CONTROL_PRESCALER_SHIFT) | + SCUTIMER_CONTROL_ENABLE_MASK; + + struct udevice *dev; + struct clk clk; + int ret; + + ret = uclass_get_device_by_driver(UCLASS_CLK, + DM_DRIVER_GET(zynq_clk), &dev); + if (ret) + return ret; + + clk.id = cpu_6or4x_clk; + ret = clk_request(dev, &clk); + if (ret < 0) + return ret; + + gd->cpu_clk = clk_get_rate(&clk); + + clk_free(&clk); + + gd->arch.timer_rate_hz = (gd->cpu_clk / 2) / (TIMER_PRESCALE + 1); + + /* Load the timer counter register */ + writel(0xFFFFFFFF, &timer_base->load); + + /* + * Start the A9Timer device + * Enable Auto reload mode, Clear prescaler control bits + * Set prescaler value, Enable the decrementer + */ + clrsetbits_le32(&timer_base->control, SCUTIMER_CONTROL_PRESCALER_MASK, + emask); + + /* Reset time */ + gd->arch.lastinc = readl(&timer_base->counter) / + (gd->arch.timer_rate_hz / CONFIG_SYS_HZ); + gd->arch.tbl = 0; + + return 0; +} + +/* + * This function is derived from PowerPC code (timebase clock frequency). + * On ARM it returns the number of timer ticks per second. + */ +ulong get_tbclk(void) +{ + return gd->arch.timer_rate_hz; +} |