[U-Boot] [PATCH] ARM: stm32f7: fix prescaler calculation of timer
As the timer 2 is on APB1 bus, the maximum of clock frequency of APB1 timer clock is half of SYSCLK. Then to calculate the timer prescaler for timer 2 which need to be divided by 2.
Signed-off-by: Bo Shen voice.shen@gmail.com --- arch/arm/mach-stm32/stm32f7/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/mach-stm32/stm32f7/timer.c b/arch/arm/mach-stm32/stm32f7/timer.c index c15f8bb..b04c101 100644 --- a/arch/arm/mach-stm32/stm32f7/timer.c +++ b/arch/arm/mach-stm32/stm32f7/timer.c @@ -26,7 +26,7 @@ int timer_init(void) /* 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, + writel((CONFIG_SYS_CLK_FREQ / 2 / CONFIG_SYS_HZ_CLOCK) - 1, &gpt1_regs_ptr->psc);
/* Configure timer for auto-reload */
-----Original Message----- From: Bo Shen [mailto:voice.shen@gmail.com] Sent: Monday, October 02, 2017 10:48 PM To: albert.u.boot@aribaud.net; Vikas MANOCHA vikas.manocha@st.com Cc: u-boot@lists.denx.de; Bo Shen voice.shen@gmail.com Subject: [PATCH] ARM: stm32f7: fix prescaler calculation of timer
As the timer 2 is on APB1 bus, the maximum of clock frequency of APB1 timer clock is half of SYSCLK. Then to calculate the timer prescaler for timer 2 which need to be divided by 2.
Signed-off-by: Bo Shen voice.shen@gmail.com
Reviewed-by: Vikas Manocha vikas.manocha@st.com
Cheers, Vikas
arch/arm/mach-stm32/stm32f7/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/mach-stm32/stm32f7/timer.c b/arch/arm/mach-stm32/stm32f7/timer.c index c15f8bb..b04c101 100644 --- a/arch/arm/mach-stm32/stm32f7/timer.c +++ b/arch/arm/mach-stm32/stm32f7/timer.c @@ -26,7 +26,7 @@ int timer_init(void) /* 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,
writel((CONFIG_SYS_CLK_FREQ / 2 / CONFIG_SYS_HZ_CLOCK) - 1, &gpt1_regs_ptr->psc);
/* Configure timer for auto-reload */
-- 2.7.4
On Mon, Oct 02, 2017 at 10:47:59PM -0700, Bo Shen wrote:
As the timer 2 is on APB1 bus, the maximum of clock frequency of APB1 timer clock is half of SYSCLK. Then to calculate the timer prescaler for timer 2 which need to be divided by 2.
Signed-off-by: Bo Shen voice.shen@gmail.com Reviewed-by: Vikas Manocha vikas.manocha@st.com
Applied to u-boot/master, thanks!
participants (3)
-
Bo Shen -
Tom Rini -
Vikas MANOCHA