make nRF SoC timer source configurable #15491
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Only nRF51 does not implement the systick timer. User can use systick to drive the timer in nRF52/nRF91 series if they need higher resolution timer. Signed-off-by: Elson Wei <elson.wei@gmail.com>
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Thanks for your contribution! |
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@elsonwei: Have you confirmed that Systick is not stopped when __WFE()/__WFI() is executed? |
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I use SysTick as the timer source on my nrf52_sparkfun board. It works fine. |
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#15212 makes the SysTick be selectable. |
| @@ -11,7 +11,7 @@ config SOC_SERIES_NRF52X | |||
| select CPU_CORTEX_M4 | |||
| select CPU_HAS_ARM_MPU | |||
| select SOC_FAMILY_NRF | |||
| select NRF_RTC_TIMER | |||
| select NRF_HAS_SYSTICK | |||
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Not needed any more - CPU_HAS_SYSTICK is selected in ARCH KConfig
| config SYSTICK_AS_TIMER | ||
| bool "Cortex-M SYSTICK timer" | ||
| depends on NRF_HAS_SYSTICK | ||
| select CPU_HAS_SYSTICK |
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Not needed any more - CPU_HAS_SYSTICK is selected in ARCH KConfig
| @@ -18,4 +18,24 @@ config SOC_FAMILY | |||
| source "soc/arm/nordic_nrf/Kconfig.peripherals" | |||
| source "soc/arm/nordic_nrf/*/Kconfig.soc" | |||
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| config NRF_HAS_SYSTICK | |||
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Not needed any more - CPU_HAS_SYSTICK is selected in ARCH KConfig
| @@ -14,7 +14,8 @@ config SOC_SERIES | |||
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| config SYS_CLOCK_HW_CYCLES_PER_SEC | |||
| int | |||
| default 32768 | |||
| default 32768 if RTC_AS_TIMER | |||
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This could work, but why not using, instead, the existing options:
NRF_RTC_TIMER and CORTEX_M_SYSTICK?
| @@ -13,7 +13,7 @@ config SOC_SERIES_NRF91X | |||
| select CPU_HAS_FPU | |||
| select ARMV8_M_DSP | |||
| select SOC_FAMILY_NRF | |||
| select NRF_RTC_TIMER | |||
| select NRF_HAS_SYSTICK | |||
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Not needed any more - CPU_HAS_SYSTICK is selected in ARCH KConfig
| @@ -14,7 +14,8 @@ config SOC_SERIES | |||
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| config SYS_CLOCK_HW_CYCLES_PER_SEC | |||
| int | |||
| default 32768 | |||
| default 32768 if RTC_AS_TIMER | |||
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This could work, but why not using, instead, the existing options:
NRF_RTC_TIMER and CORTEX_M_SYSTICK?
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So, first, I agree that you should have the option to use any available HW timer you prefer, as a source for your system timer. Let's agree that the up-streamed nRF Boards need to have a default timer. And that shall be the NRF_RTC_TIMER. In #15212 we have done some cleanup and removed the "default y" in SYSTICK and NRF_RTC timer Kconfig options. IMO, if you want to use the SysTick, you should simply do: in your prj.conf. And the same for the cycles-per-second: We might still need to remove the default setting of the NRF_RTC_TIMER from SOC definition and move it to nrf Board definition, if the above setting does not work. |
That's really interesting; could you solve this problem for all ARM boards? |
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Only nRF51 does not implement the systick timer.
User can use systick to drive the timer in nRF52/nRF91 series if
they need higher resolution timer.