[PATCH v1 04/16] ACPICA: Allow to skip Global Lock initialization

Rafael J. Wysocki
2025-09-12T20:06:56Z

From: Huacai Chen <chenhuacai@loongson.cn>

Introduce acpi_gbl_use_global_lock, which allows to skip the Global Lock
initialization. This is useful for systems without Global Lock (such as
loong_arch), so as to avoid error messages during boot phase:

ACPI Error: Could not enable global_lock event (20240827/evxfevnt-182)
ACPI Error: No response from Global Lock hardware, disabling lock (20240827/evglock-59)

Link: https://github.com/acpica/acpica/commit/463cb0fe
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/acpi/acpica/evglock.c | 4 ++++
include/acpi/acpixf.h | 6 ++++++
2 files changed, 10 insertions(+)

diff --git a/drivers/acpi/acpica/evglock.c b/drivers/acpi/acpica/evglock.c
index fa3e0d00d1ca..df2a4ab0e0da 100644
--- a/drivers/acpi/acpica/evglock.c
+++ b/drivers/acpi/acpica/evglock.c
@@ -42,6 +42,10 @@ acpi_status acpi_ev_init_global_lock_handler(void)
return_ACPI_STATUS(AE_OK);
}

+ if (!acpi_gbl_use_global_lock) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
/* Attempt installation of the global lock handler */

status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index b49396aa4058..97c25ae8a36e 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -213,6 +213,12 @@ ACPI_INIT_GLOBAL(u8, acpi_gbl_osi_data, 0);
*/
ACPI_INIT_GLOBAL(u8, acpi_gbl_reduced_hardware, FALSE);

+/*
+ * ACPI Global Lock is mainly used for systems with SMM, so no-SMM systems
+ * (such as loong_arch) may not have and not use Global Lock.
+ */
+ACPI_INIT_GLOBAL(u8, acpi_gbl_use_global_lock, TRUE);
+
/*
* Maximum timeout for While() loop iterations before forced method abort.
* This mechanism is intended to prevent infinite loops during interpreter
--
2.51.0