ACPICA: Minimize the differences between linux GPE code and ACPICA code base

We have ported Rafael's major GPE changes
(ACPI: Use GPE reference counting to support shared GPEs) into ACPICA code base.
But the port and Rafael's original patch have some differences, so we made
below patch to make linux GPE code consistent with ACPICA code base.

Most changes are about comments and coding styles.
Other noticeable changes are based on:

Rafael: Reduce code duplication related to GPE lookup
https://patchwork.kernel.org/patch/86237/

Rafael: Always use the same lock for GPE locking
https://patchwork.kernel.org/patch/90471/

A new field gpe_count in struct acpi_gpe_block_info to record the number
of individual GPEs in block.

Rename acpi_ev_save_method_info to acpi_ev_match_gpe_method.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Robert Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/acpica/acevents.h

@@ -85,6 +85,10 @@ acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info);
 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 						       u32 gpe_number);
 
+struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
+						     struct acpi_gpe_block_info
+						     *gpe_block);
+
 /*
  * evgpeblk
  */
@@ -118,9 +122,6 @@ acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info,
 
 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list);
 
-acpi_status
-acpi_ev_check_for_wake_only_gpe(struct acpi_gpe_event_info *gpe_event_info);
-
 acpi_status acpi_ev_gpe_initialize(void);
 
 /*

drivers/acpi/acpica/aclocal.h

@@ -427,8 +427,8 @@ struct acpi_gpe_event_info {
 	struct acpi_gpe_register_info *register_info;	/* Backpointer to register info */
 	u8 flags;		/* Misc info about this GPE */
 	u8 gpe_number;		/* This GPE */
-	u8 runtime_count;
-	u8 wakeup_count;
+	u8 runtime_count;	/* References to a run GPE */
+	u8 wakeup_count;	/* References to a wake GPE */
 };
 
 /* Information about a GPE register pair, one per each status/enable pair in an array */
@@ -454,6 +454,7 @@ struct acpi_gpe_block_info {
 	struct acpi_gpe_event_info *event_info;	/* One for each GPE */
 	struct acpi_generic_address block_address;	/* Base address of the block */
 	u32 register_count;	/* Number of register pairs in block */
+	u16 gpe_count;		/* Number of individual GPEs in block */
 	u8 block_base_number;	/* Base GPE number for this block */
 };
 

drivers/acpi/acpica/evgpe.c

@@ -60,7 +60,8 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
  *
  * RETURN:      Status
  *
- * DESCRIPTION: Updates GPE register enable masks based on the GPE type
+ * DESCRIPTION: Updates GPE register enable masks based upon whether there are
+ *              references (either wake or run) to this GPE
  *
  ******************************************************************************/
 
@@ -81,14 +82,20 @@ acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info)
 	    (1 <<
 	     (gpe_event_info->gpe_number - gpe_register_info->base_gpe_number));
 
+	/* Clear the wake/run bits up front */
+
 	ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake, register_bit);
 	ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
 
-	if (gpe_event_info->runtime_count)
+	/* Set the mask bits only if there are references to this GPE */
+
+	if (gpe_event_info->runtime_count) {
 		ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
+	}
 
-	if (gpe_event_info->wakeup_count)
+	if (gpe_event_info->wakeup_count) {
 		ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
+	}
 
 	return_ACPI_STATUS(AE_OK);
 }
@@ -101,7 +108,10 @@ acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info)
  *
  * RETURN:      Status
  *
- * DESCRIPTION: Enable a GPE based on the GPE type
+ * DESCRIPTION: Hardware-enable a GPE. Always enables the GPE, regardless
+ *              of type or number of references.
+ *
+ * Note: The GPE lock should be already acquired when this function is called.
  *
  ******************************************************************************/
 
@@ -109,20 +119,36 @@ acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 {
 	acpi_status status;
 
+
 	ACPI_FUNCTION_TRACE(ev_enable_gpe);
 
-	/* Make sure HW enable masks are updated */
+
+	/*
+	 * We will only allow a GPE to be enabled if it has either an
+	 * associated method (_Lxx/_Exx) or a handler. Otherwise, the
+	 * GPE will be immediately disabled by acpi_ev_gpe_dispatch the
+	 * first time it fires.
+	 */
+	if (!(gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)) {
+		return_ACPI_STATUS(AE_NO_HANDLER);
+	}
+
+	/* Ensure the HW enable masks are current */
 
 	status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
-	if (ACPI_FAILURE(status))
+	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
+	}
+
+	/* Clear the GPE (of stale events) */
 
-	/* Clear the GPE (of stale events), then enable it */
 	status = acpi_hw_clear_gpe(gpe_event_info);
-	if (ACPI_FAILURE(status))
+	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
+	}
 
 	/* Enable the requested GPE */
+
 	status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
 	return_ACPI_STATUS(status);
 }
@@ -135,7 +161,10 @@ acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
  *
  * RETURN:      Status
  *
- * DESCRIPTION: Disable a GPE based on the GPE type
+ * DESCRIPTION: Hardware-disable a GPE. Always disables the requested GPE,
+ *              regardless of the type or number of references.
+ *
+ * Note: The GPE lock should be already acquired when this function is called.
  *
  ******************************************************************************/
 
@@ -145,24 +174,71 @@ acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 
 	ACPI_FUNCTION_TRACE(ev_disable_gpe);
 
-	/* Make sure HW enable masks are updated */
+
+	/*
+	 * Note: Always disable the GPE, even if we think that that it is already
+	 * disabled. It is possible that the AML or some other code has enabled
+	 * the GPE behind our back.
+	 */
+
+	/* Ensure the HW enable masks are current */
 
 	status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
-	if (ACPI_FAILURE(status))
+	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
+	}
 
 	/*
-	 * Even if we don't know the GPE type, make sure that we always
-	 * disable it. low_disable_gpe will just clear the enable bit for this
-	 * GPE and write it. It will not write out the current GPE enable mask,
-	 * since this may inadvertently enable GPEs too early, if a rogue GPE has
-	 * come in during ACPICA initialization - possibly as a result of AML or
-	 * other code that has enabled the GPE.
+	 * Always H/W disable this GPE, even if we don't know the GPE type.
+	 * Simply clear the enable bit for this particular GPE, but do not
+	 * write out the current GPE enable mask since this may inadvertently
+	 * enable GPEs too early. An example is a rogue GPE that has arrived
+	 * during ACPICA initialization - possibly because AML or other code
+	 * has enabled the GPE.
 	 */
 	status = acpi_hw_low_disable_gpe(gpe_event_info);
 	return_ACPI_STATUS(status);
 }
 
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_low_get_gpe_info
+ *
+ * PARAMETERS:  gpe_number          - Raw GPE number
+ *              gpe_block           - A GPE info block
+ *
+ * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
+ *              is not within the specified GPE block)
+ *
+ * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
+ *              the low-level implementation of ev_get_gpe_event_info.
+ *
+ ******************************************************************************/
+
+struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
+						     struct acpi_gpe_block_info
+						     *gpe_block)
+{
+	u32 gpe_index;
+
+	/*
+	 * Validate that the gpe_number is within the specified gpe_block.
+	 * (Two steps)
+	 */
+	if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
+		return (NULL);
+	}
+
+	gpe_index = gpe_number - gpe_block->block_base_number;
+	if (gpe_index >= gpe_block->gpe_count) {
+		return (NULL);
+	}
+
+	return (&gpe_block->event_info[gpe_index]);
+}
+
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ev_get_gpe_event_info
@@ -184,7 +260,7 @@ struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 						       u32 gpe_number)
 {
 	union acpi_operand_object *obj_desc;
-	struct acpi_gpe_block_info *gpe_block;
+	struct acpi_gpe_event_info *gpe_info;
 	u32 i;
 
 	ACPI_FUNCTION_ENTRY();
@@ -196,17 +272,11 @@ struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 		/* Examine GPE Block 0 and 1 (These blocks are permanent) */
 
 		for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
-			gpe_block = acpi_gbl_gpe_fadt_blocks[i];
-			if (gpe_block) {
-				if ((gpe_number >= gpe_block->block_base_number)
-				    && (gpe_number <
-					gpe_block->block_base_number +
-					(gpe_block->register_count * 8))) {
-					return (&gpe_block->
-						event_info[gpe_number -
-							   gpe_block->
-							   block_base_number]);
-				}
+			gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
+							    acpi_gbl_gpe_fadt_blocks
+							    [i]);
+			if (gpe_info) {
+				return (gpe_info);
 			}
 		}
 
@@ -223,16 +293,8 @@ struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 		return (NULL);
 	}
 
-	gpe_block = obj_desc->device.gpe_block;
-
-	if ((gpe_number >= gpe_block->block_base_number) &&
-	    (gpe_number <
-	     gpe_block->block_base_number + (gpe_block->register_count * 8))) {
-		return (&gpe_block->
-			event_info[gpe_number - gpe_block->block_base_number]);
-	}
-
-	return (NULL);
+	return (acpi_ev_low_get_gpe_info
+		(gpe_number, obj_desc->device.gpe_block));
 }
 
 /*******************************************************************************
@@ -389,7 +451,7 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 		return_VOID;
 	}
 
-	/* Set the GPE flags for return to enabled state */
+	/* Update the GPE register masks for return to enabled state */
 
 	(void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
 
@@ -569,15 +631,18 @@ acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 
 	default:
 
-		/* No handler or method to run! */
-
+		/*
+		 * No handler or method to run!
+		 * 03/2010: This case should no longer be possible. We will not allow
+		 * a GPE to be enabled if it has no handler or method.
+		 */
 		ACPI_ERROR((AE_INFO,
 			    "No handler or method for GPE[0x%2X], disabling event",
 			    gpe_number));
 
 		/*
-		 * Disable the GPE. The GPE will remain disabled until the ACPICA
-		 * Core Subsystem is restarted, or a handler is installed.
+		 * Disable the GPE. The GPE will remain disabled a handler
+		 * is installed or ACPICA is restarted.
 		 */
 		status = acpi_ev_disable_gpe(gpe_event_info);
 		if (ACPI_FAILURE(status)) {

drivers/acpi/acpica/evxface.c

@@ -682,14 +682,13 @@ acpi_install_gpe_handler(acpi_handle gpe_device,
 
 	/* Parameter validation */
 
-	if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
-		status = AE_BAD_PARAMETER;
-		goto exit;
+	if ((!address) || (type & ~ACPI_GPE_XRUPT_TYPE_MASK)) {
+		return_ACPI_STATUS(AE_BAD_PARAMETER);
 	}
 
 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 	if (ACPI_FAILURE(status)) {
-		goto exit;
+		return_ACPI_STATUS(status);
 	}
 
 	/* Ensure that we have a valid GPE number */
@@ -720,6 +719,13 @@ acpi_install_gpe_handler(acpi_handle gpe_device,
 	handler->context = context;
 	handler->method_node = gpe_event_info->dispatch.method_node;
 
+	/* Disable the GPE before installing the handler */
+
+	status = acpi_ev_disable_gpe(gpe_event_info);
+	if (ACPI_FAILURE (status)) {
+		goto unlock_and_exit;
+	}
+
 	/* Install the handler */
 
 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
@@ -733,12 +739,8 @@ acpi_install_gpe_handler(acpi_handle gpe_device,
 
 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 
-      unlock_and_exit:
+unlock_and_exit:
 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
-      exit:
-	if (ACPI_FAILURE(status))
-		ACPI_EXCEPTION((AE_INFO, status,
-				"Installing notify handler failed"));
 	return_ACPI_STATUS(status);
 }
 

drivers/acpi/acpica/exoparg2.c

@@ -119,33 +119,6 @@ acpi_status acpi_ex_opcode_2A_0T_0R(struct acpi_walk_state *walk_state)
 			status = AE_AML_OPERAND_TYPE;
 			break;
 		}
-#ifdef ACPI_GPE_NOTIFY_CHECK
-		/*
-		 * GPE method wake/notify check.  Here, we want to ensure that we
-		 * don't receive any "DeviceWake" Notifies from a GPE _Lxx or _Exx
-		 * GPE method during system runtime.  If we do, the GPE is marked
-		 * as "wake-only" and disabled.
-		 *
-		 * 1) Is the Notify() value == device_wake?
-		 * 2) Is this a GPE deferred method?  (An _Lxx or _Exx method)
-		 * 3) Did the original GPE happen at system runtime?
-		 *    (versus during wake)
-		 *
-		 * If all three cases are true, this is a wake-only GPE that should
-		 * be disabled at runtime.
-		 */
-		if (value == 2) {	/* device_wake */
-			status =
-			    acpi_ev_check_for_wake_only_gpe(walk_state->
-							    gpe_event_info);
-			if (ACPI_FAILURE(status)) {
-
-				/* AE_WAKE_ONLY_GPE only error, means ignore this notify */
-
-				return_ACPI_STATUS(AE_OK)
-			}
-		}
-#endif
 
 		/*
 		 * Dispatch the notify to the appropriate handler

drivers/acpi/scan.c

@@ -765,7 +765,7 @@ static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 	}
 
 	status = acpi_get_gpe_status(NULL, device->wakeup.gpe_number,
-					ACPI_NOT_ISR, &event_status);
+					&event_status);
 	if (status == AE_OK)
 		device->wakeup.flags.run_wake =
 				!!(event_status & ACPI_EVENT_FLAG_HANDLE);

drivers/acpi/system.c

@@ -303,8 +303,7 @@ static int get_status(u32 index, acpi_event_status *status, acpi_handle *handle)
 				"Invalid GPE 0x%x\n", index));
 			goto end;
 		}
-		result = acpi_get_gpe_status(*handle, index,
-						ACPI_NOT_ISR, status);
+		result = acpi_get_gpe_status(*handle, index, status);
 	} else if (index < (num_gpes + ACPI_NUM_FIXED_EVENTS))
 		result = acpi_get_event_status(index - num_gpes, status);
 
@@ -395,7 +394,7 @@ static ssize_t counter_set(struct kobject *kobj,
 			result = acpi_set_gpe(handle, index, ACPI_GPE_ENABLE);
 		else if (!strcmp(buf, "clear\n") &&
 				(status & ACPI_EVENT_FLAG_SET))
-			result = acpi_clear_gpe(handle, index, ACPI_NOT_ISR);
+			result = acpi_clear_gpe(handle, index);
 		else
 			all_counters[index].count = strtoul(buf, NULL, 0);
 	} else if (index < num_gpes + ACPI_NUM_FIXED_EVENTS) {

include/acpi/acexcep.h

@@ -87,7 +87,7 @@
 #define AE_NO_GLOBAL_LOCK               (acpi_status) (0x0017 | AE_CODE_ENVIRONMENTAL)
 #define AE_ABORT_METHOD                 (acpi_status) (0x0018 | AE_CODE_ENVIRONMENTAL)
 #define AE_SAME_HANDLER                 (acpi_status) (0x0019 | AE_CODE_ENVIRONMENTAL)
-#define AE_WAKE_ONLY_GPE                (acpi_status) (0x001A | AE_CODE_ENVIRONMENTAL)
+#define AE_NO_HANDLER                   (acpi_status) (0x001A | AE_CODE_ENVIRONMENTAL)
 #define AE_OWNER_ID_LIMIT               (acpi_status) (0x001B | AE_CODE_ENVIRONMENTAL)
 
 #define AE_CODE_ENV_MAX                 0x001B

include/acpi/acpixf.h

@@ -285,16 +285,17 @@ acpi_status acpi_get_event_status(u32 event, acpi_event_status * event_status);
  */
 acpi_status acpi_set_gpe(acpi_handle gpe_device, u32 gpe_number, u8 action);
 
-acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 type);
+acpi_status
+acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type);
 
-acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 type);
+acpi_status
+acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type);
 
-acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number, u32 flags);
+acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number);
 
 acpi_status
 acpi_get_gpe_status(acpi_handle gpe_device,
-		    u32 gpe_number,
-		    u32 flags, acpi_event_status * event_status);
+		    u32 gpe_number, acpi_event_status *event_status);
 
 acpi_status acpi_disable_all_gpes(void);
 

include/acpi/actypes.h

@@ -663,44 +663,42 @@ typedef u32 acpi_event_status;
 #define ACPI_GPE_MAX                    0xFF
 #define ACPI_NUM_GPE                    256
 
+/* Actions for acpi_set_gpe */
+
 #define ACPI_GPE_ENABLE                 0
 #define ACPI_GPE_DISABLE                1
 
+/* gpe_types for acpi_enable_gpe and acpi_disable_gpe */
+
+#define ACPI_GPE_TYPE_WAKE              (u8) 0x01
+#define ACPI_GPE_TYPE_RUNTIME           (u8) 0x02
+#define ACPI_GPE_TYPE_WAKE_RUN          (u8) 0x03
+
 /*
  * GPE info flags - Per GPE
- * +-+-+-+---+-+-+-+
- * |7|6|5|4:3|2|1|0|
- * +-+-+-+---+-+-+-+
- *  | | |  |  | | |
- *  | | |  |  | | +--- Interrupt type: Edge or Level Triggered
- *  | | |  |  | +--- GPE can wake the system
- *  | | |  |  +--- Unused
- *  | | |  +--- Type of dispatch -- to method, handler, or none
- *  | | +--- Unused
- *  | +--- Unused
- *  +--- Unused
+ * +-------+---+-+-+
+ * |  7:4  |3:2|1|0|
+ * +-------+---+-+-+
+ *     |     |  | |
+ *     |     |  | +--- Interrupt type: edge or level triggered
+ *     |     |  +----- GPE can wake the system
+ *     |     +-------- Type of dispatch:to method, handler, or none
+ *     +-------------- <Reserved>
  */
 #define ACPI_GPE_XRUPT_TYPE_MASK        (u8) 0x01
 #define ACPI_GPE_LEVEL_TRIGGERED        (u8) 0x01
 #define ACPI_GPE_EDGE_TRIGGERED         (u8) 0x00
 
-#define ACPI_GPE_TYPE_MASK              (u8) 0x06
-#define ACPI_GPE_TYPE_WAKE_RUN          (u8) 0x06
-#define ACPI_GPE_TYPE_WAKE              (u8) 0x02
-#define ACPI_GPE_TYPE_RUNTIME           (u8) 0x04	/* Default */
 #define ACPI_GPE_CAN_WAKE		(u8) 0x02
 
-#define ACPI_GPE_DISPATCH_MASK          (u8) 0x18
-#define ACPI_GPE_DISPATCH_HANDLER       (u8) 0x08
-#define ACPI_GPE_DISPATCH_METHOD        (u8) 0x10
-#define ACPI_GPE_DISPATCH_NOT_USED      (u8) 0x00	/* Default */
+#define ACPI_GPE_DISPATCH_MASK          (u8) 0x0C
+#define ACPI_GPE_DISPATCH_HANDLER       (u8) 0x04
+#define ACPI_GPE_DISPATCH_METHOD        (u8) 0x08
+#define ACPI_GPE_DISPATCH_NOT_USED      (u8) 0x00
 
 /*
  * Flags for GPE and Lock interfaces
  */
-#define ACPI_EVENT_WAKE_ENABLE          0x2	/* acpi_gpe_enable */
-#define ACPI_EVENT_WAKE_DISABLE         0x2	/* acpi_gpe_disable */
-
 #define ACPI_NOT_ISR                    0x1
 #define ACPI_ISR                        0x0