u-boot/arch/arm/mach-stm32/stm32f7/timer.c
Michael Kurz 081de09d49 ARM: stm32: use clock setup function defined in clock.c
Use the clock setup function defined in clock.c instead of setting the
clock bits directly in the drivers.
Remove register definitions of RCC in rcc.h as these are already
defined in the struct in stm32.h

Signed-off-by: Michael Kurz <michi.kurz@gmail.com>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Vikas Manocha <vikas.manocha@st.com>
2017-01-28 14:04:45 -05:00

112 lines
2.3 KiB
C

/*
* (C) Copyright 2016
* Vikas Manocha, ST Micoelectronics, vikas.manocha@st.com.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/stm32.h>
#include <asm/arch/stm32_defs.h>
#include <asm/arch/gpt.h>
#define READ_TIMER() (readl(&gpt1_regs_ptr->cnt) & GPT_FREE_RUNNING)
#define GPT_RESOLUTION (CONFIG_SYS_HZ_CLOCK/CONFIG_STM32_HZ)
DECLARE_GLOBAL_DATA_PTR;
#define timestamp gd->arch.tbl
#define lastdec gd->arch.lastinc
int timer_init(void)
{
/* Timer2 clock configuration */
clock_setup(TIMER2_CLOCK_CFG);
/* Stop the timer */
writel(readl(&gpt1_regs_ptr->cr1) & ~GPT_CR1_CEN, &gpt1_regs_ptr->cr1);
writel((CONFIG_SYS_CLK_FREQ/CONFIG_SYS_HZ_CLOCK) - 1,
&gpt1_regs_ptr->psc);
/* Configure timer for auto-reload */
writel(readl(&gpt1_regs_ptr->cr1) | GPT_MODE_AUTO_RELOAD,
&gpt1_regs_ptr->cr1);
/* load value for free running */
writel(GPT_FREE_RUNNING, &gpt1_regs_ptr->arr);
/* start timer */
writel(readl(&gpt1_regs_ptr->cr1) | GPT_CR1_CEN, &gpt1_regs_ptr->cr1);
writel(readl(&gpt1_regs_ptr->egr) | TIM_EGR_UG, &gpt1_regs_ptr->egr);
/* Reset the timer */
lastdec = READ_TIMER();
timestamp = 0;
return 0;
}
/*
* timer without interrupts
*/
ulong get_timer(ulong base)
{
return (get_timer_masked() / GPT_RESOLUTION) - base;
}
void __udelay(unsigned long usec)
{
ulong tmo;
ulong start = get_timer_masked();
ulong tenudelcnt = CONFIG_SYS_HZ_CLOCK / (1000 * 100);
ulong rndoff;
rndoff = (usec % 10) ? 1 : 0;
/* tenudelcnt timer tick gives 10 microsecconds delay */
tmo = ((usec / 10) + rndoff) * tenudelcnt;
while ((ulong) (get_timer_masked() - start) < tmo)
;
}
ulong get_timer_masked(void)
{
ulong now = READ_TIMER();
if (now >= lastdec) {
/* normal mode */
timestamp += now - lastdec;
} else {
/* we have an overflow ... */
timestamp += now + GPT_FREE_RUNNING - lastdec;
}
lastdec = now;
return timestamp;
}
void udelay_masked(unsigned long usec)
{
return udelay(usec);
}
/*
* This function is derived from PowerPC code (read timebase as long long).
* On ARM it just returns the timer value.
*/
unsigned long long get_ticks(void)
{
return get_timer(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 CONFIG_STM32_HZ;
}