ACPICA: Events: Support fixed PCIe wake event

ACPICA commit 32d875705c8ee8f99fd8b78dbed48633486a7640

Some chipsets (such as Loongson's LS7A) support fixed pcie wake event
which is defined in the PM1 block(related description can be found in
4.8.4.1.1 PM1 Status Registers, 4.8.4.2.1 PM1 Control Registers and
5.2.9 Fixed ACPI Description Table (FADT)), so we add code to handle it.

Link: https://uefi.org/specifications/ACPI/6.4/
Link: acpica/acpica@32d87570
Co-developed-by: Jianmin Lv <[email protected]>
Signed-off-by: Jianmin Lv <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>
Signed-off-by: Bob Moore <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

Author: chenhuacai

drivers/acpi/acpica/evevent.c

@@ -142,6 +142,9 @@ static acpi_status acpi_ev_fixed_event_initialize(void)
 			status =
 			    acpi_write_bit_register(acpi_gbl_fixed_event_info
 						    [i].enable_register_id,
+						    (i ==
+						     ACPI_EVENT_PCIE_WAKE) ?
+						    ACPI_ENABLE_EVENT :
 						    ACPI_DISABLE_EVENT);
 			if (ACPI_FAILURE(status)) {
 				return (status);
@@ -185,6 +188,11 @@ 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));
@@ -250,6 +258,9 @@ 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,
+					      (event ==
+					       ACPI_EVENT_PCIE_WAKE) ?
+					      ACPI_ENABLE_EVENT :
 					      ACPI_DISABLE_EVENT);
 
 		ACPI_ERROR((AE_INFO,

drivers/acpi/acpica/hwsleep.c

@@ -311,6 +311,20 @@ 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);
 }

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 */
 

include/acpi/actypes.h

@@ -723,7 +723,8 @@ 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
 
 /*