On 17/07/2020 08:13, Zhou Yanjie wrote: > Hi Daniel, > > 在 2020/7/17 下午12:20, Daniel Lezcano 写道: >> On 10/07/2020 19:02, 周琰杰 (Zhou Yanjie) wrote: >>> X1000 and SoCs after X1000 (such as X1500 and X1830) had a separate >>> OST, it no longer belongs to TCU. This driver will register both a >>> clocksource and a sched_clock to the system. >>> >>> Tested-by: 周正 (Zhou Zheng) <sernia.zhou@xxxxxxxxxxx> >>> Co-developed-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@xxxxxxxxxxx> >>> Signed-off-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@xxxxxxxxxxx> >>> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@xxxxxxxxxxxxxx> >>> Reviewed-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> >>> --- >>> >>> Notes: >>> v1->v2: >>> Fix compile warnings. >>> Reported-by: kernel test robot <lkp@xxxxxxxxx> >>> v2->v3: >>> No change. >>> v3->v4: >>> 1.Rename "ost" to "sysost" >>> 1.Remove unrelated changes. >>> 2.Remove ost_clock_parent enum. >>> 3.Remove ost->percpu_timer_channel/ost->global_timer_channel. >>> 4.Set up independent .recalc_rate/.set_rate for percpu/global >>> timer. >>> 5.No longer call functions in variable declarations. >>> v4->v5: >>> Use "of_io_request_and_map()" instead "of_iomap()". >>> Suggested-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> >>> v5->v6: >>> No change. >>> >>> drivers/clocksource/Kconfig | 11 + >>> drivers/clocksource/Makefile | 1 + >>> drivers/clocksource/ingenic-sysost.c | 539 >>> +++++++++++++++++++++++++++++++++++ >>> 3 files changed, 551 insertions(+) >>> create mode 100644 drivers/clocksource/ingenic-sysost.c >>> >>> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig >>> index 91418381fcd4..1bca8b8fb30f 100644 >>> --- a/drivers/clocksource/Kconfig >>> +++ b/drivers/clocksource/Kconfig >>> @@ -696,6 +696,17 @@ config INGENIC_TIMER >>> help >>> Support for the timer/counter unit of the Ingenic JZ SoCs. >>> +config INGENIC_SYSOST >>> + bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" >> We usually use silent options and let the platform's Kconfig enable it. >> We show up the option only when COMPILE_TEST is enabled. >> >> Is there a reason to do it differently? > > > Do you mean > > bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" > > or > > default MACH_INGENIC ? Both, no default here. eg. bool "Clocksource/timer using the SYSOST in Ingenic X SoCs" if COMPILE_TEST and in arch/mips/Kconfig in the config MACH_INGENIC section : ... select INGENIC_SYSOST ... > This driver has some origins from "INGENIC_TIMER" driver and > "INGENIC_OST" driver. > Early Ingenic processors used TCU (timer/counter unit, has 6 or 8 > generic timer channels) to provide clocksource and clockevent (both with > only 16bit precision). This part of the processor can only use > "INGENIC_TIMER" driver. > > Later processors provide an independent 32bit or 64bit timer channel > (still under TCU, known as ost channel, this channel can not generate > interrupt) to provid higher precision clocksource. The "INGENIC_OST" > driver is for this channel. These processors can use "INGENIC_TIMER" > driver, but using "INGENIC_OST" driver to provide higher precision > clocksource would be a better choice (clockevent still needs to be > provided by generic timer channel of TCU, and still 16bit precision). > > And the recent processors provide a SYSOST components, it is independent > from TCU, including a 64bit timer channel for clocksource and a 32bit > timer channel for clockevent. Although these processors can also use > "INGENIC_TIMER" driver, but the better choice is completely independent > use of "INGENIC_SYSOST" driver to provide higher precision clocksource > and clockevent. Ok, the rating should do the job then. Thanks for the explanation. > You may have already noticed that this independent SYSOST component is > like an upgraded and streamlined TCU, which only retains one generic > timer channel that can generate interrupts, upgrade it from 16bit to > 32bit, and then retain the 64bit ost channel. so the driver code and > Kconfig code of this patch is largely referenced > "INGENIC_TIMER" driver and "INGENIC_OST" driver. > > Thanks and best regards! > >>> + default MACH_INGENIC >>> + depends on MIPS || COMPILE_TEST >>> + depends on COMMON_CLK >>> + select MFD_SYSCON >>> + select TIMER_OF >>> + select IRQ_DOMAIN >>> + help >>> + Support for the SYSOST of the Ingenic X Series SoCs. >>> + >> [ ... ] >> >> -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
