[PATCH v2] clocksource/drivers/riscv: Get rid of clocksource_arch_init() callback

From: Prabhakar
Date: Thu Dec 29 2022 - 17:50:40 EST


From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Having a clocksource_arch_init() callback always sets vdso_clock_mode to
VDSO_CLOCKMODE_ARCHTIMER if GENERIC_GETTIMEOFDAY is enabled, this is
required for the riscv-timer.

This works for platforms where just riscv-timer clocksource is present.
On platforms where other clock sources are available we want them to
register with vdso_clock_mode set to VDSO_CLOCKMODE_NONE.

On the Renesas RZ/Five SoC OSTM block can be used as clocksource [0], to
avoid multiple clock sources being registered as VDSO_CLOCKMODE_ARCHTIMER
move setting of vdso_clock_mode in the riscv-timer driver instead of doing
this in clocksource_arch_init() callback as done similarly for ARM/64
architecture.

[0] drivers/clocksource/renesas-ostm.c

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Tested-by: Samuel Holland <samuel@xxxxxxxxxxxx>
---
RFC -> v2
* Dropped vdso_default static global variable
* Used IS_ENABLED() macro
* Included Tested-by from Samuel

RFC:
https://patchwork.kernel.org/project/linux-renesas-soc/patch/20221211215843.24024-1-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx/
---
arch/riscv/Kconfig | 1 -
arch/riscv/kernel/time.c | 9 ---------
drivers/clocksource/timer-riscv.c | 5 +++++
3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index e2b656043abf..9c687da7756d 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -12,7 +12,6 @@ config 32BIT

config RISCV
def_bool y
- select ARCH_CLOCKSOURCE_INIT
select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
select ARCH_HAS_BINFMT_FLAT
diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
index 8217b0f67c6c..42bee305e997 100644
--- a/arch/riscv/kernel/time.c
+++ b/arch/riscv/kernel/time.c
@@ -30,12 +30,3 @@ void __init time_init(void)
of_clk_init(NULL);
timer_probe();
}
-
-void clocksource_arch_init(struct clocksource *cs)
-{
-#ifdef CONFIG_GENERIC_GETTIMEOFDAY
- cs->vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER;
-#else
- cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE;
-#endif
-}
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 55dad7965f43..c416e5e934bf 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -77,6 +77,11 @@ static struct clocksource riscv_clocksource = {
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
.read = riscv_clocksource_rdtime,
+#if IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY)
+ .vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER,
+#else
+ .vdso_clock_mode = VDSO_CLOCKMODE_NONE,
+#endif
};

static int riscv_timer_starting_cpu(unsigned int cpu)
--
2.25.1