[PATCH AUTOSEL 4.19 081/209] ACPICA: Never run _REG on system_memory and system_IO

From: Sasha Levin
Date: Tue Nov 12 2019 - 20:52:26 EST


From: Bob Moore <robert.moore@xxxxxxxxx>

[ Upstream commit 8b1cafdcb4b75c5027c52f1e82b47ebe727ad7ed ]

These address spaces are defined by the ACPI spec to be
"always available", and thus _REG should never be run on them.
Provides compatibility with other ACPI implementations.

Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
Signed-off-by: Erik Schmauss <erik.schmauss@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/acpi/acpica/acevents.h | 2 ++
drivers/acpi/acpica/aclocal.h | 2 +-
drivers/acpi/acpica/evregion.c | 17 +++++++++++++++--
drivers/acpi/acpica/evrgnini.c | 6 +-----
drivers/acpi/acpica/evxfregn.c | 1 -
5 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/acpi/acpica/acevents.h b/drivers/acpi/acpica/acevents.h
index 298180bf7e3c1..bfcc68b9f708d 100644
--- a/drivers/acpi/acpica/acevents.h
+++ b/drivers/acpi/acpica/acevents.h
@@ -230,6 +230,8 @@ acpi_ev_default_region_setup(acpi_handle handle,

acpi_status acpi_ev_initialize_region(union acpi_operand_object *region_obj);

+u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node);
+
/*
* evsci - SCI (System Control Interrupt) handling/dispatch
*/
diff --git a/drivers/acpi/acpica/aclocal.h b/drivers/acpi/acpica/aclocal.h
index 0f28a38a43ea1..99b0da8991098 100644
--- a/drivers/acpi/acpica/aclocal.h
+++ b/drivers/acpi/acpica/aclocal.h
@@ -395,9 +395,9 @@ struct acpi_simple_repair_info {
/* Info for running the _REG methods */

struct acpi_reg_walk_info {
- acpi_adr_space_type space_id;
u32 function;
u32 reg_run_count;
+ acpi_adr_space_type space_id;
};

/*****************************************************************************
diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c
index 70c2bd169f669..49decca4e08ff 100644
--- a/drivers/acpi/acpica/evregion.c
+++ b/drivers/acpi/acpica/evregion.c
@@ -653,6 +653,19 @@ acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,

ACPI_FUNCTION_TRACE(ev_execute_reg_methods);

+ /*
+ * These address spaces do not need a call to _REG, since the ACPI
+ * specification defines them as: "must always be accessible". Since
+ * they never change state (never become unavailable), no need to ever
+ * call _REG on them. Also, a data_table is not a "real" address space,
+ * so do not call _REG. September 2018.
+ */
+ if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
+ (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
+ (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
+ return_VOID;
+ }
+
info.space_id = space_id;
info.function = function;
info.reg_run_count = 0;
@@ -714,8 +727,8 @@ acpi_ev_reg_run(acpi_handle obj_handle,
}

/*
- * We only care about regions.and objects that are allowed to have address
- * space handlers
+ * We only care about regions and objects that are allowed to have
+ * address space handlers
*/
if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
return (AE_OK);
diff --git a/drivers/acpi/acpica/evrgnini.c b/drivers/acpi/acpica/evrgnini.c
index 39284deedd885..17df5dacd43cf 100644
--- a/drivers/acpi/acpica/evrgnini.c
+++ b/drivers/acpi/acpica/evrgnini.c
@@ -16,9 +16,6 @@
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME("evrgnini")

-/* Local prototypes */
-static u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node);
-
/*******************************************************************************
*
* FUNCTION: acpi_ev_system_memory_region_setup
@@ -33,7 +30,6 @@ static u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node);
* DESCRIPTION: Setup a system_memory operation region
*
******************************************************************************/
-
acpi_status
acpi_ev_system_memory_region_setup(acpi_handle handle,
u32 function,
@@ -313,7 +309,7 @@ acpi_ev_pci_config_region_setup(acpi_handle handle,
*
******************************************************************************/

-static u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node)
+u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node)
{
acpi_status status;
struct acpi_pnp_device_id *hid;
diff --git a/drivers/acpi/acpica/evxfregn.c b/drivers/acpi/acpica/evxfregn.c
index 091415b14fbf1..3b3a25d9f0e6d 100644
--- a/drivers/acpi/acpica/evxfregn.c
+++ b/drivers/acpi/acpica/evxfregn.c
@@ -193,7 +193,6 @@ acpi_remove_address_space_handler(acpi_handle device,
*/
region_obj =
handler_obj->address_space.region_list;
-
}

/* Remove this Handler object from the list */
--
2.20.1