alistair23-linux/drivers/acpi/acpica/evgpeblk.c
Lv Zheng 0d0988af81 ACPICA: Events: Introduce ACPI_GPE_DISPATCH_RAW_HANDLER to fix 2 issues for the current GPE APIs
ACPICA commit 199cad16530a45aea2bec98e528866e20c5927e1

Since whether the GPE should be disabled/enabled/cleared should only be
determined by the GPE driver's state machine:
1. GPE should be disabled if the driver wants to switch to the GPE polling
   mode when a GPE storm condition is indicated and should be enabled if
   the driver wants to switch back to the GPE interrupt mode when all of
   the storm conditions are cleared. The conditions should be protected by
   the driver's specific lock.
2. GPE should be enabled if the driver has accepted more than one request
   and should be disabled if the driver has completed all of the requests.
   The request count should be protected by the driver's specific lock.
3. GPE should be cleared either when the driver is about to handle an edge
   triggered GPE or when the driver has completed to handle a level
   triggered GPE. The handling code should be protected by the driver's
   specific lock.
Thus the GPE enabling/disabling/clearing operations are likely to be
performed with the driver's specific lock held while we currently cannot do
this. This is because:
1. We have the acpi_gbl_gpe_lock held before invoking the GPE driver's
   handler. Driver's specific lock is likely to be held inside of the
   handler, thus we can see some dead lock issues due to the reversed
   locking order or recursive locking. In order to solve such dead lock
   issues, we need to unlock the acpi_gbl_gpe_lock before invoking the
   handler. BZ 1100.
2. Since GPE disabling/enabling/clearing should be determined by the GPE
   driver's state machine, we shouldn't perform such operations inside of
   ACPICA for a GPE handler to mess up the driver's state machine. BZ 1101.

Originally this patch includes a logic to flush GPE handlers, it is dropped
due to the following reasons:
1. This is a different issue;
2. Linux OSL has fixed this by flushing SCI in acpi_os_wait_events_complete().
We will pick up this topic when the Linux OSL fix turns out to be not
sufficient.

Note that currently the internal operations and the acpi_gbl_gpe_lock are
also used by ACPI_GPE_DISPATCH_METHOD and ACPI_GPE_DISPATCH_NOTIFY. In
order not to introduce regressions, we add one
ACPI_GPE_DISPATCH_RAW_HANDLER type to be distiguished from
ACPI_GPE_DISPATCH_HANDLER. For which the acpi_gbl_gpe_lock is unlocked before
invoking the GPE handler and the internal enabling/disabling operations are
bypassed to allow drivers to perform them at a proper position using the
GPE APIs and ACPI_GPE_DISPATCH_RAW_HANDLER users should invoke acpi_set_gpe()
instead of acpi_enable_gpe()/acpi_disable_gpe() to bypass the internal GPE
clearing code in acpi_enable_gpe(). Lv Zheng.

Known issues:
1. Edge-triggered GPE lost for frequent enablings
   On some buggy silicon platforms, GPE enable line may not be directly
   wired to the GPE trigger line. In that case, when GPE enabling is
   frequently performed for edge-triggered GPEs, GPE status may stay set
   without being triggered.
   This patch may maginify this problem as it allows GPE enabling to be
   parallel performed during the process the GPEs are handled.
   This is an existing issue, because:
   1. For task context:
      Current ACPI_GPE_DISPATCH_METHOD practices have proven that this
      isn't a real issue - we can re-enable edge-triggered GPE in a work
      queue where the GPE status bit might already be set.
   2. For IRQ context:
      This can even happen when the GPE enabling occurs before returning
      from the GPE handler and after unlocking the GPE lock.
   Thus currently no code is included to protect this.

Link: https://github.com/acpica/acpica/commit/199cad16
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-05 15:34:51 +01:00

514 lines
15 KiB
C

/******************************************************************************
*
* Module Name: evgpeblk - GPE block creation and initialization.
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2015, Intel Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME("evgpeblk")
#if (!ACPI_REDUCED_HARDWARE) /* Entire module */
/* Local prototypes */
static acpi_status
acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
u32 interrupt_number);
static acpi_status
acpi_ev_create_gpe_info_blocks(struct acpi_gpe_block_info *gpe_block);
/*******************************************************************************
*
* FUNCTION: acpi_ev_install_gpe_block
*
* PARAMETERS: gpe_block - New GPE block
* interrupt_number - Xrupt to be associated with this
* GPE block
*
* RETURN: Status
*
* DESCRIPTION: Install new GPE block with mutex support
*
******************************************************************************/
static acpi_status
acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
u32 interrupt_number)
{
struct acpi_gpe_block_info *next_gpe_block;
struct acpi_gpe_xrupt_info *gpe_xrupt_block;
acpi_status status;
acpi_cpu_flags flags;
ACPI_FUNCTION_TRACE(ev_install_gpe_block);
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
status =
acpi_ev_get_gpe_xrupt_block(interrupt_number, &gpe_xrupt_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* Install the new block at the end of the list with lock */
flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
if (gpe_xrupt_block->gpe_block_list_head) {
next_gpe_block = gpe_xrupt_block->gpe_block_list_head;
while (next_gpe_block->next) {
next_gpe_block = next_gpe_block->next;
}
next_gpe_block->next = gpe_block;
gpe_block->previous = next_gpe_block;
} else {
gpe_xrupt_block->gpe_block_list_head = gpe_block;
}
gpe_block->xrupt_block = gpe_xrupt_block;
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_delete_gpe_block
*
* PARAMETERS: gpe_block - Existing GPE block
*
* RETURN: Status
*
* DESCRIPTION: Remove a GPE block
*
******************************************************************************/
acpi_status acpi_ev_delete_gpe_block(struct acpi_gpe_block_info *gpe_block)
{
acpi_status status;
acpi_cpu_flags flags;
ACPI_FUNCTION_TRACE(ev_install_gpe_block);
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Disable all GPEs in this block */
status =
acpi_hw_disable_gpe_block(gpe_block->xrupt_block, gpe_block, NULL);
if (!gpe_block->previous && !gpe_block->next) {
/* This is the last gpe_block on this interrupt */
status = acpi_ev_delete_gpe_xrupt(gpe_block->xrupt_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
} else {
/* Remove the block on this interrupt with lock */
flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
if (gpe_block->previous) {
gpe_block->previous->next = gpe_block->next;
} else {
gpe_block->xrupt_block->gpe_block_list_head =
gpe_block->next;
}
if (gpe_block->next) {
gpe_block->next->previous = gpe_block->previous;
}
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
}
acpi_current_gpe_count -= gpe_block->gpe_count;
/* Free the gpe_block */
ACPI_FREE(gpe_block->register_info);
ACPI_FREE(gpe_block->event_info);
ACPI_FREE(gpe_block);
unlock_and_exit:
status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_create_gpe_info_blocks
*
* PARAMETERS: gpe_block - New GPE block
*
* RETURN: Status
*
* DESCRIPTION: Create the register_info and event_info blocks for this GPE block
*
******************************************************************************/
static acpi_status
acpi_ev_create_gpe_info_blocks(struct acpi_gpe_block_info *gpe_block)
{
struct acpi_gpe_register_info *gpe_register_info = NULL;
struct acpi_gpe_event_info *gpe_event_info = NULL;
struct acpi_gpe_event_info *this_event;
struct acpi_gpe_register_info *this_register;
u32 i;
u32 j;
acpi_status status;
ACPI_FUNCTION_TRACE(ev_create_gpe_info_blocks);
/* Allocate the GPE register information block */
gpe_register_info = ACPI_ALLOCATE_ZEROED((acpi_size) gpe_block->
register_count *
sizeof(struct
acpi_gpe_register_info));
if (!gpe_register_info) {
ACPI_ERROR((AE_INFO,
"Could not allocate the GpeRegisterInfo table"));
return_ACPI_STATUS(AE_NO_MEMORY);
}
/*
* Allocate the GPE event_info block. There are eight distinct GPEs
* per register. Initialization to zeros is sufficient.
*/
gpe_event_info = ACPI_ALLOCATE_ZEROED((acpi_size) gpe_block->gpe_count *
sizeof(struct
acpi_gpe_event_info));
if (!gpe_event_info) {
ACPI_ERROR((AE_INFO,
"Could not allocate the GpeEventInfo table"));
status = AE_NO_MEMORY;
goto error_exit;
}
/* Save the new Info arrays in the GPE block */
gpe_block->register_info = gpe_register_info;
gpe_block->event_info = gpe_event_info;
/*
* Initialize the GPE Register and Event structures. A goal of these
* tables is to hide the fact that there are two separate GPE register
* sets in a given GPE hardware block, the status registers occupy the
* first half, and the enable registers occupy the second half.
*/
this_register = gpe_register_info;
this_event = gpe_event_info;
for (i = 0; i < gpe_block->register_count; i++) {
/* Init the register_info for this GPE register (8 GPEs) */
this_register->base_gpe_number = (u16)
(gpe_block->block_base_number +
(i * ACPI_GPE_REGISTER_WIDTH));
this_register->status_address.address = gpe_block->address + i;
this_register->enable_address.address =
gpe_block->address + i + gpe_block->register_count;
this_register->status_address.space_id = gpe_block->space_id;
this_register->enable_address.space_id = gpe_block->space_id;
this_register->status_address.bit_width =
ACPI_GPE_REGISTER_WIDTH;
this_register->enable_address.bit_width =
ACPI_GPE_REGISTER_WIDTH;
this_register->status_address.bit_offset = 0;
this_register->enable_address.bit_offset = 0;
/* Init the event_info for each GPE within this register */
for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
this_event->gpe_number =
(u8) (this_register->base_gpe_number + j);
this_event->register_info = this_register;
this_event++;
}
/* Disable all GPEs within this register */
status = acpi_hw_write(0x00, &this_register->enable_address);
if (ACPI_FAILURE(status)) {
goto error_exit;
}
/* Clear any pending GPE events within this register */
status = acpi_hw_write(0xFF, &this_register->status_address);
if (ACPI_FAILURE(status)) {
goto error_exit;
}
this_register++;
}
return_ACPI_STATUS(AE_OK);
error_exit:
if (gpe_register_info) {
ACPI_FREE(gpe_register_info);
}
if (gpe_event_info) {
ACPI_FREE(gpe_event_info);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_create_gpe_block
*
* PARAMETERS: gpe_device - Handle to the parent GPE block
* gpe_block_address - Address and space_ID
* register_count - Number of GPE register pairs in the block
* gpe_block_base_number - Starting GPE number for the block
* interrupt_number - H/W interrupt for the block
* return_gpe_block - Where the new block descriptor is returned
*
* RETURN: Status
*
* DESCRIPTION: Create and Install a block of GPE registers. All GPEs within
* the block are disabled at exit.
* Note: Assumes namespace is locked.
*
******************************************************************************/
acpi_status
acpi_ev_create_gpe_block(struct acpi_namespace_node *gpe_device,
u64 address,
u8 space_id,
u32 register_count,
u16 gpe_block_base_number,
u32 interrupt_number,
struct acpi_gpe_block_info **return_gpe_block)
{
acpi_status status;
struct acpi_gpe_block_info *gpe_block;
struct acpi_gpe_walk_info walk_info;
ACPI_FUNCTION_TRACE(ev_create_gpe_block);
if (!register_count) {
return_ACPI_STATUS(AE_OK);
}
/* Allocate a new GPE block */
gpe_block = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_block_info));
if (!gpe_block) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Initialize the new GPE block */
gpe_block->address = address;
gpe_block->space_id = space_id;
gpe_block->node = gpe_device;
gpe_block->gpe_count = (u16)(register_count * ACPI_GPE_REGISTER_WIDTH);
gpe_block->initialized = FALSE;
gpe_block->register_count = register_count;
gpe_block->block_base_number = gpe_block_base_number;
/*
* Create the register_info and event_info sub-structures
* Note: disables and clears all GPEs in the block
*/
status = acpi_ev_create_gpe_info_blocks(gpe_block);
if (ACPI_FAILURE(status)) {
ACPI_FREE(gpe_block);
return_ACPI_STATUS(status);
}
/* Install the new block in the global lists */
status = acpi_ev_install_gpe_block(gpe_block, interrupt_number);
if (ACPI_FAILURE(status)) {
ACPI_FREE(gpe_block->register_info);
ACPI_FREE(gpe_block->event_info);
ACPI_FREE(gpe_block);
return_ACPI_STATUS(status);
}
acpi_gbl_all_gpes_initialized = FALSE;
/* Find all GPE methods (_Lxx or_Exx) for this block */
walk_info.gpe_block = gpe_block;
walk_info.gpe_device = gpe_device;
walk_info.execute_by_owner_id = FALSE;
status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD, gpe_device,
ACPI_UINT32_MAX, ACPI_NS_WALK_NO_UNLOCK,
acpi_ev_match_gpe_method, NULL,
&walk_info, NULL);
/* Return the new block */
if (return_gpe_block) {
(*return_gpe_block) = gpe_block;
}
ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
" Initialized GPE %02X to %02X [%4.4s] %u regs on interrupt 0x%X%s\n",
(u32)gpe_block->block_base_number,
(u32)(gpe_block->block_base_number +
(gpe_block->gpe_count - 1)),
gpe_device->name.ascii, gpe_block->register_count,
interrupt_number,
interrupt_number ==
acpi_gbl_FADT.sci_interrupt ? " (SCI)" : ""));
/* Update global count of currently available GPEs */
acpi_current_gpe_count += gpe_block->gpe_count;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_initialize_gpe_block
*
* PARAMETERS: acpi_gpe_callback
*
* RETURN: Status
*
* DESCRIPTION: Initialize and enable a GPE block. Enable GPEs that have
* associated methods.
* Note: Assumes namespace is locked.
*
******************************************************************************/
acpi_status
acpi_ev_initialize_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
struct acpi_gpe_block_info *gpe_block,
void *ignored)
{
acpi_status status;
struct acpi_gpe_event_info *gpe_event_info;
u32 gpe_enabled_count;
u32 gpe_index;
u32 i;
u32 j;
ACPI_FUNCTION_TRACE(ev_initialize_gpe_block);
/*
* Ignore a null GPE block (e.g., if no GPE block 1 exists), and
* any GPE blocks that have been initialized already.
*/
if (!gpe_block || gpe_block->initialized) {
return_ACPI_STATUS(AE_OK);
}
/*
* Enable all GPEs that have a corresponding method and have the
* ACPI_GPE_CAN_WAKE flag unset. Any other GPEs within this block
* must be enabled via the acpi_enable_gpe() interface.
*/
gpe_enabled_count = 0;
for (i = 0; i < gpe_block->register_count; i++) {
for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
/* Get the info block for this particular GPE */
gpe_index = (i * ACPI_GPE_REGISTER_WIDTH) + j;
gpe_event_info = &gpe_block->event_info[gpe_index];
/*
* Ignore GPEs that have no corresponding _Lxx/_Exx method
* and GPEs that are used to wake the system
*/
if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_NONE)
|| (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_HANDLER)
|| (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_RAW_HANDLER)
|| (gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {
continue;
}
status = acpi_ev_add_gpe_reference(gpe_event_info);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Could not enable GPE 0x%02X",
gpe_index +
gpe_block->block_base_number));
continue;
}
gpe_enabled_count++;
}
}
if (gpe_enabled_count) {
ACPI_INFO((AE_INFO,
"Enabled %u GPEs in block %02X to %02X",
gpe_enabled_count, (u32)gpe_block->block_base_number,
(u32)(gpe_block->block_base_number +
(gpe_block->gpe_count - 1))));
}
gpe_block->initialized = TRUE;
return_ACPI_STATUS(AE_OK);
}
#endif /* !ACPI_REDUCED_HARDWARE */