From 03acd21a4e00752d82ce1f3198960b52c475396e Mon Sep 17 00:00:00 2001 From: Scott Soule Cheloha Date: Wed, 23 Aug 2023 01:55:48 +0000 Subject: all platforms: separate cpu_initclocks() from cpu_startclock() To give the primary CPU an opportunity to perform clock interrupt preparation in a machine-independent manner we need to separate the "initialization" parts of cpu_initclocks() from the "start the clock interrupt" parts. Currently, cpu_initclocks() does everything all at once, so there is no space for this MI setup. Many platforms have more-or-less already done this separation by implementing a separate routine named "cpu_startclock()". This patch promotes cpu_startclock() from de facto standard to mandatory API. - Prototype cpu_startclock() in sys/systm.h alongside cpu_initclocks(). The separation of responsibility between the two routines is a bit fuzzy but the basic guidelines are as follows: + cpu_initclocks() must initialize hz, stathz, and profhz, and call clockintr_init(). + cpu_startclock() must call clockintr_cpu_init() and start the clock interrupt cycle on the calling CPU. These guidelines will shift in the future, but that's the way things stand as of *this* commit. - In initclocks(): first call cpu_initclocks(), then do MI setup, and last call cpu_startclock(). - On platforms where cpu_startclock() already exists: don't call cpu_startclock() from cpu_initclocks() anymore. - On platforms where cpu_startclock() doesn't yet exist: implement it. Usually this is as simple as dividing cpu_initclocks() in two. Tested on amd64 (i8254, lapic), arm64, i386 (i8254, lapic), macppc, mips64/octeon, and sparc64. Tested on arm/armv7 (agtimer(4)) by phessler@ and jmatthew@. Tested on m88k/luna88k by aoyama@. Tested on powerpc64 by gkoehler@ and mlarkin@. Tested on riscv64 by jmatthew@. Thread: https://marc.info/?l=openbsd-tech&m=169195251322149&w=2 --- sys/arch/alpha/alpha/clock.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'sys/arch/alpha') diff --git a/sys/arch/alpha/alpha/clock.c b/sys/arch/alpha/alpha/clock.c index c03cd35993d..dd3ad3f75b2 100644 --- a/sys/arch/alpha/alpha/clock.c +++ b/sys/arch/alpha/alpha/clock.c @@ -1,4 +1,4 @@ -/* $OpenBSD: clock.c,v 1.29 2023/08/21 15:19:09 cheloha Exp $ */ +/* $OpenBSD: clock.c,v 1.30 2023/08/23 01:55:45 cheloha Exp $ */ /* $NetBSD: clock.c,v 1.29 2000/06/05 21:47:10 thorpej Exp $ */ /* @@ -192,7 +192,11 @@ cpu_initclocks(void) stathz = hz; profhz = stathz; clockintr_init(0); +} +void +cpu_startclock(void) +{ clockintr_cpu_init(NULL); /* -- cgit v1.2.3