clk: samsung: gs101: fix synchronous external abort in samsung_clk_save()

Commit Message

Peter Griffin March 3, 2025, 1:11 p.m. UTC

EARLY_WAKEUP_SW_TRIG_*_SET and EARLY_WAKEUP_SW_TRIG_*_CLEAR
registers are only writeable. Attempting to read these registers
during samsung_clk_save() causes a synchronous external abort.

Remove these 8 registers from cmu_top_clk_regs[] array so that
system suspend gets further.

Note: the code path can be exercised using the following command:
echo mem > /sys/power/state

Fixes: 2c597bb7d66a ("clk: samsung: clk-gs101: Add cmu_top, cmu_misc and cmu_apm support")
Signed-off-by: Peter Griffin <[e-mail]>
Cc: [e-mail]
---
Note: to hit this clock driver issue you also need the CPU hotplug
series otherwise system fails earlier offlining CPUs
Link: https://lore.kernel.org/linux-arm-kernel/202412[e-mail]/T/
---
 drivers/clk/samsung/clk-gs101.c | 8 --------
 1 file changed, 8 deletions(-)


---
base-commit: 480112512bd6e770fa1902d01173731d02377705
change-id: 20250303-clk-suspend-fix-81c5d63827e3

Best regards,

Patch

diff --git a/drivers/clk/samsung/clk-gs101.c b/drivers/clk/samsung/clk-gs101.c
index 86b39edba122..08b867ae3ed9 100644
--- a/drivers/clk/samsung/clk-gs101.c
+++ b/drivers/clk/samsung/clk-gs101.c
@@ -382,17 +382,9 @@  static const unsigned long cmu_top_clk_regs[] __initconst = {
 	EARLY_WAKEUP_DPU_DEST,
 	EARLY_WAKEUP_CSIS_DEST,
 	EARLY_WAKEUP_SW_TRIG_APM,
-	EARLY_WAKEUP_SW_TRIG_APM_SET,
-	EARLY_WAKEUP_SW_TRIG_APM_CLEAR,
 	EARLY_WAKEUP_SW_TRIG_CLUSTER0,
-	EARLY_WAKEUP_SW_TRIG_CLUSTER0_SET,
-	EARLY_WAKEUP_SW_TRIG_CLUSTER0_CLEAR,
 	EARLY_WAKEUP_SW_TRIG_DPU,
-	EARLY_WAKEUP_SW_TRIG_DPU_SET,
-	EARLY_WAKEUP_SW_TRIG_DPU_CLEAR,
 	EARLY_WAKEUP_SW_TRIG_CSIS,
-	EARLY_WAKEUP_SW_TRIG_CSIS_SET,
-	EARLY_WAKEUP_SW_TRIG_CSIS_CLEAR,
 	CLK_CON_MUX_MUX_CLKCMU_BO_BUS,
 	CLK_CON_MUX_MUX_CLKCMU_BUS0_BUS,
 	CLK_CON_MUX_MUX_CLKCMU_BUS1_BUS,