[PATCH v2] ACPICA: Events: support fixed pcie wake event

[Jianmin Lv]

Some chipsets support fixed pcie wake event which is
defined in the PM1 block(related description can be found
in 4.8.3.1.1 PM1 Status Registers, 4.8.3.2.1 PM1 Control
Registers and 5.2.9 Fixed ACPI Description Table (FADT)),
such as LS7A1000 of Loongson company, so we add code to
handle it.

ACPI spec link:
https://uefi.org/sites/default/files/resources/ACPI_6_3_May16.pdf

Signed-off-by: Jianmin Lv <lvjianmin@xxxxxxxxxxx>
---
 drivers/acpi/acpica/evevent.c  |  8 ++++++--
 drivers/acpi/acpica/hwsleep.c  | 12 ++++++++++++
 drivers/acpi/acpica/utglobal.c |  4 ++++
 include/acpi/actypes.h         |  3 ++-
 4 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/acpica/evevent.c b/drivers/acpi/acpica/evevent.c
index 35385148fedb..08ba368beb2d 100644
--- a/drivers/acpi/acpica/evevent.c
+++ b/drivers/acpi/acpica/evevent.c
@@ -185,6 +185,10 @@ u32 acpi_ev_fixed_event_detect(void)
 		return (int_status);
 	}
 
+	if (fixed_enable & ACPI_BITMASK_PCIEXP_WAKE_DISABLE)
+		fixed_enable &= ~ACPI_BITMASK_PCIEXP_WAKE_DISABLE;
+	else
+		fixed_enable |= ACPI_BITMASK_PCIEXP_WAKE_DISABLE;
 	ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 			  "Fixed Event Block: Enable %08X Status %08X\n",
 			  fixed_enable, fixed_status));
@@ -250,8 +254,8 @@ static u32 acpi_ev_fixed_event_dispatch(u32 event)
 	if (!acpi_gbl_fixed_event_handlers[event].handler) {
 		(void)acpi_write_bit_register(acpi_gbl_fixed_event_info[event].
 					      enable_register_id,
-					      ACPI_DISABLE_EVENT);
-
+						event == ACPI_EVENT_PCIE_WAKE ?
+						ACPI_ENABLE_EVENT : ACPI_DISABLE_EVENT);
 		ACPI_ERROR((AE_INFO,
 			    "No installed handler for fixed event - %s (%u), disabling",
 			    acpi_ut_get_event_name(event), event));
diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c
index 14baa13bf848..7e7ea4c2e914 100644
--- a/drivers/acpi/acpica/hwsleep.c
+++ b/drivers/acpi/acpica/hwsleep.c
@@ -312,6 +312,18 @@ acpi_status acpi_hw_legacy_wake(u8 sleep_state)
 				    [ACPI_EVENT_SLEEP_BUTTON].
 				    status_register_id, ACPI_CLEAR_STATUS);
 
+	/* Enable pcie wake event if support */
+	if ((acpi_gbl_FADT.flags & ACPI_FADT_PCI_EXPRESS_WAKE)) {
+		(void)
+		acpi_write_bit_register(acpi_gbl_fixed_event_info
+				[ACPI_EVENT_PCIE_WAKE].
+				enable_register_id, ACPI_DISABLE_EVENT);
+		(void)
+		acpi_write_bit_register(acpi_gbl_fixed_event_info
+				[ACPI_EVENT_PCIE_WAKE].
+				status_register_id, ACPI_CLEAR_STATUS);
+	}
+
 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
 	return_ACPI_STATUS(status);
 }
diff --git a/drivers/acpi/acpica/utglobal.c b/drivers/acpi/acpica/utglobal.c
index 59a48371a7bc..68baf16d8a02 100644
--- a/drivers/acpi/acpica/utglobal.c
+++ b/drivers/acpi/acpica/utglobal.c
@@ -186,6 +186,10 @@ struct acpi_fixed_event_info acpi_gbl_fixed_event_info[ACPI_NUM_FIXED_EVENTS] =
 					ACPI_BITREG_RT_CLOCK_ENABLE,
 					ACPI_BITMASK_RT_CLOCK_STATUS,
 					ACPI_BITMASK_RT_CLOCK_ENABLE},
+	/* ACPI_EVENT_PCIE_WAKE		*/ {ACPI_BITREG_PCIEXP_WAKE_STATUS,
+					ACPI_BITREG_PCIEXP_WAKE_DISABLE,
+					ACPI_BITMASK_PCIEXP_WAKE_STATUS,
+					ACPI_BITMASK_PCIEXP_WAKE_DISABLE},
 };
 #endif				/* !ACPI_REDUCED_HARDWARE */
 
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index 92c71dfce0d5..0b6c72033487 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -714,7 +714,8 @@ typedef u32 acpi_event_type;
 #define ACPI_EVENT_POWER_BUTTON         2
 #define ACPI_EVENT_SLEEP_BUTTON         3
 #define ACPI_EVENT_RTC                  4
-#define ACPI_EVENT_MAX                  4
+#define ACPI_EVENT_PCIE_WAKE            5
+#define ACPI_EVENT_MAX                  5
 #define ACPI_NUM_FIXED_EVENTS           ACPI_EVENT_MAX + 1
 
 /*
-- 
2.27.0