[PATCH] clocksource/drivers/sun5i: Allow enabling the driver on 64-bit sunxi

[Arun Iyengar via B4 Relay]

From: Arun Iyengar <aiyengar1990@xxxxxxxxx>

The high-speed timer driver binds "allwinner,sun20i-d1-hstimer", which
the H616 device tree uses as the fallback compatible of its
"allwinner,sun50i-h616-hstimer" node and the D1/T113 device tree uses
directly. SUN5I_HSTIMER, however, only has a prompt under COMPILE_TEST
and is selected by the 32-bit sunxi machine Kconfig alone, so arm64 and
RISC-V sunxi kernels cannot enable it and these nodes never probe.

Make the prompt visible on ARCH_SUNXI. The driver registers its
clocksource and clockevent at rating 340: below the architected timer's
clocksource (400) and below the sun4i timer (350), which ARCH_SUNXI
already selects on arm64 and RISC-V. Enabling it therefore adds a
second hardware time base without changing which one the kernel uses.

Signed-off-by: Arun Iyengar <aiyengar1990@xxxxxxxxx>
---
The H616 and D1/T113 hstimer nodes and the D1 driver support were merged
for 7.2, but the driver still cannot be enabled outside COMPILE_TEST on
arm64 and RISC-V.

Tested on an Orange Pi Zero2 (H616) with a 7.3 kernel carrying this
patch and CONFIG_SUN5I_HSTIMER=y: the hstimer node at 0x3005000
probes and available_clocksource lists "arch_sys_counter timer
hstimer".

This patch was developed with Claude (Anthropic) as a coding
assistant. It investigated the problem and wrote the code and the commit
message; I reviewed it, and it was tested on an Orange Pi Zero2 (H616)
as described above.
---
 drivers/clocksource/Kconfig | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index da83483296d5..971491d2e584 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -172,12 +172,17 @@ config SUN4I_TIMER
 	  Enables support for the Sun4i timer.
 
 config SUN5I_HSTIMER
-	bool "Sun5i timer driver" if COMPILE_TEST
+	bool "Sun5i timer driver" if COMPILE_TEST || ARCH_SUNXI
 	select CLKSRC_MMIO
 	depends on COMMON_CLK
 	help
 	  Enables support the Sun5i timer.
 
+	  The 32-bit sunxi platforms that have this timer select it. On
+	  64-bit (ARM64, RISC-V) sunxi SoCs such as the H616 and D1 it
+	  registers an additional clocksource and clockevent device, rated
+	  below the ones the kernel already uses there.
+
 config TEGRA_TIMER
 	bool "Tegra timer driver" if COMPILE_TEST
 	select CLKSRC_MMIO

---
base-commit: 7475ea8b58616b33c04afb976cf0fbaad9dd63fb
change-id: 20261110-sun5i-hstimer-arch-sunxi-167ea2ebcbd7

Best regards,
--  
Arun Iyengar <aiyengar1990@xxxxxxxxx>