[PATCH v2] reset: spacemit: Fix the RCPU2 PWM reset registers

[PATCH v2] reset: spacemit: Fix the RCPU2 PWM reset registers

[Hung-Chun Tseng]

Every entry in k1_rcpu2_resets[] uses RCPU2_PWM9_CLK_RST, so asserting
or deasserting the reset of any RCPU2 PWM from 0 to 8 acts on PWM9
instead. Each PWM has its own register, RCPU2_PWMn_CLK_RST at offset
4 * n, as k1-syscon.h already defines.

On a Milk-V Jupiter running the vendor kernel, which uses RCPU2 PWM2
for the fan, the RCPU2 registers read:

  0x00: 0x4  0x04: 0x4  0x08: 0x1  0x0c: 0x4  ...  0x24: 0x4

Only PWM2's register has its reset deasserted, which matches one
register per PWM.

Use the matching register for each reset. No in-tree device tree uses
the RCPU2 PWMs yet, so this has no effect on current boards, but it
would break the first one that does.

Build-tested only (riscv defconfig, W=1); the fix could not be tested
at runtime, as mainline has no RCPU2 PWM node to exercise it.

Fixes: c479d7cf06c3 ("reset: spacemit: add support for SpacemiT CCU resets")
Signed-off-by: Hung-Chun Tseng <alan.tseng.cs@gmail.com>
Reviewed-by: Yixun Lan <dlan@kernel.org>
Reviewed-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
---
Changes in v2:
- Drop the Assisted-by tag (Philipp)
- Collect Reviewed-by tags from Yixun, Troy and Philipp

I used Claude to help find the bug and read the vendor driver. I
checked the register dump on the board and the patch myself.

v1: https://lore.kernel.org/all/20261017140805.3278709-1-alan.tseng.cs@gmail.com/

 drivers/reset/spacemit/reset-spacemit-k1.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/reset/spacemit/reset-spacemit-k1.c b/drivers/reset/spacemit/reset-spacemit-k1.c
index 8f3b5329ea..dbd783c138 100644
--- a/drivers/reset/spacemit/reset-spacemit-k1.c
+++ b/drivers/reset/spacemit/reset-spacemit-k1.c
@@ -154,15 +154,15 @@ static const struct ccu_reset_controller_data k1_rcpu_reset_data = {
 };
 
 static const struct ccu_reset_data k1_rcpu2_resets[] = {
-	[RESET_RCPU2_PWM0]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM1]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM2]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM3]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM4]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM5]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM6]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM7]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
-	[RESET_RCPU2_PWM8]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM0]	= RESET_DATA(RCPU2_PWM0_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM1]	= RESET_DATA(RCPU2_PWM1_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM2]	= RESET_DATA(RCPU2_PWM2_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM3]	= RESET_DATA(RCPU2_PWM3_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM4]	= RESET_DATA(RCPU2_PWM4_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM5]	= RESET_DATA(RCPU2_PWM5_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM6]	= RESET_DATA(RCPU2_PWM6_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM7]	= RESET_DATA(RCPU2_PWM7_CLK_RST, BIT(2), BIT(0)),
+	[RESET_RCPU2_PWM8]	= RESET_DATA(RCPU2_PWM8_CLK_RST, BIT(2), BIT(0)),
 	[RESET_RCPU2_PWM9]	= RESET_DATA(RCPU2_PWM9_CLK_RST, BIT(2), BIT(0)),
 };
 
-- 
2.43.0