linux_dsm_epyc7002/drivers/acpi/acpica/hwxface.c
Steven Rostedt c57c0ad4a3 ACPICA: Convert acpi_gbl_hardware lock back to an acpi_raw_spinlock
We hit the following bug with -RT:

|BUG: scheduling while atomic: swapper/7/0/0x00000002
|Pid: 0, comm: swapper/7 Not tainted 3.6.11-rt28.19.el6rt.x86_64.debug #1
|Call Trace:
|  rt_spin_lock+0x16/0x40
|  __schedule_bug+0x67/0x90
|  __schedule+0x793/0x7a0
|  acpi_os_acquire_lock+0x1f/0x23
|  acpi_write_bit_register+0x33/0xb0
|  rt_spin_lock_slowlock+0xe5/0x2f0
|  acpi_idle_enter_bm+0x8a/0x28e
…
As the acpi code disables interrupts in acpi_idle_enter_bm, and calls
code that grabs the acpi lock, it causes issues as the lock is currently
in RT a sleeping lock.

The lock was converted from a raw to a sleeping lock due to some
previous issues, and tests that showed it didn't seem to matter.
Unfortunately, it did matter for one of our boxes.

This patch converts the lock back to a raw lock. I've run this code on a
few of my own machines, one being my laptop that uses the acpi quite
extensively. I've been able to suspend and resume without issues.

[ tglx: Made the change exclusive for acpi_gbl_hardware_lock ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1360765565.23152.5.camel@gandalf.local.home
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: shorten the backtrace, use the type acpi_raw_spinlock incl.
 accessor]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-10 17:18:45 +02:00

449 lines
13 KiB
C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: hwxface - Public ACPICA hardware interfaces
*
* Copyright (C) 2000 - 2018, Intel Corp.
*
*****************************************************************************/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_HARDWARE
ACPI_MODULE_NAME("hwxface")
/******************************************************************************
*
* FUNCTION: acpi_reset
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Set reset register in memory or IO space. Note: Does not
* support reset register in PCI config space, this must be
* handled separately.
*
******************************************************************************/
acpi_status acpi_reset(void)
{
struct acpi_generic_address *reset_reg;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_reset);
reset_reg = &acpi_gbl_FADT.reset_register;
/* Check if the reset register is supported */
if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) ||
!reset_reg->address) {
return_ACPI_STATUS(AE_NOT_EXIST);
}
if (reset_reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
/*
* For I/O space, write directly to the OSL. This bypasses the port
* validation mechanism, which may block a valid write to the reset
* register.
*
* NOTE:
* The ACPI spec requires the reset register width to be 8, so we
* hardcode it here and ignore the FADT value. This maintains
* compatibility with other ACPI implementations that have allowed
* BIOS code with bad register width values to go unnoticed.
*/
status = acpi_os_write_port((acpi_io_address)reset_reg->address,
acpi_gbl_FADT.reset_value,
ACPI_RESET_REGISTER_WIDTH);
} else {
/* Write the reset value to the reset register */
status = acpi_hw_write(acpi_gbl_FADT.reset_value, reset_reg);
}
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_reset)
/******************************************************************************
*
* FUNCTION: acpi_read
*
* PARAMETERS: value - Where the value is returned
* reg - GAS register structure
*
* RETURN: Status
*
* DESCRIPTION: Read from either memory or IO space.
*
* LIMITATIONS: <These limitations also apply to acpi_write>
* bit_width must be exactly 8, 16, 32, or 64.
* space_ID must be system_memory or system_IO.
* bit_offset and access_width are currently ignored, as there has
* not been a need to implement these.
*
******************************************************************************/
acpi_status acpi_read(u64 *return_value, struct acpi_generic_address *reg)
{
acpi_status status;
ACPI_FUNCTION_NAME(acpi_read);
status = acpi_hw_read(return_value, reg);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_read)
/******************************************************************************
*
* FUNCTION: acpi_write
*
* PARAMETERS: value - Value to be written
* reg - GAS register structure
*
* RETURN: Status
*
* DESCRIPTION: Write to either memory or IO space.
*
******************************************************************************/
acpi_status acpi_write(u64 value, struct acpi_generic_address *reg)
{
acpi_status status;
ACPI_FUNCTION_NAME(acpi_write);
status = acpi_hw_write(value, reg);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_write)
#if (!ACPI_REDUCED_HARDWARE)
/*******************************************************************************
*
* FUNCTION: acpi_read_bit_register
*
* PARAMETERS: register_id - ID of ACPI Bit Register to access
* return_value - Value that was read from the register,
* normalized to bit position zero.
*
* RETURN: Status and the value read from the specified Register. Value
* returned is normalized to bit0 (is shifted all the way right)
*
* DESCRIPTION: ACPI bit_register read function. Does not acquire the HW lock.
*
* SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
* PM2 Control.
*
* Note: The hardware lock is not required when reading the ACPI bit registers
* since almost all of them are single bit and it does not matter that
* the parent hardware register can be split across two physical
* registers. The only multi-bit field is SLP_TYP in the PM1 control
* register, but this field does not cross an 8-bit boundary (nor does
* it make much sense to actually read this field.)
*
******************************************************************************/
acpi_status acpi_read_bit_register(u32 register_id, u32 *return_value)
{
struct acpi_bit_register_info *bit_reg_info;
u32 register_value;
u32 value;
acpi_status status;
ACPI_FUNCTION_TRACE_U32(acpi_read_bit_register, register_id);
/* Get the info structure corresponding to the requested ACPI Register */
bit_reg_info = acpi_hw_get_bit_register_info(register_id);
if (!bit_reg_info) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Read the entire parent register */
status = acpi_hw_register_read(bit_reg_info->parent_register,
&register_value);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Normalize the value that was read, mask off other bits */
value = ((register_value & bit_reg_info->access_bit_mask)
>> bit_reg_info->bit_position);
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"BitReg %X, ParentReg %X, Actual %8.8X, ReturnValue %8.8X\n",
register_id, bit_reg_info->parent_register,
register_value, value));
*return_value = value;
return_ACPI_STATUS(AE_OK);
}
ACPI_EXPORT_SYMBOL(acpi_read_bit_register)
/*******************************************************************************
*
* FUNCTION: acpi_write_bit_register
*
* PARAMETERS: register_id - ID of ACPI Bit Register to access
* value - Value to write to the register, in bit
* position zero. The bit is automatically
* shifted to the correct position.
*
* RETURN: Status
*
* DESCRIPTION: ACPI Bit Register write function. Acquires the hardware lock
* since most operations require a read/modify/write sequence.
*
* SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
* PM2 Control.
*
* Note that at this level, the fact that there may be actually two
* hardware registers (A and B - and B may not exist) is abstracted.
*
******************************************************************************/
acpi_status acpi_write_bit_register(u32 register_id, u32 value)
{
struct acpi_bit_register_info *bit_reg_info;
acpi_cpu_flags lock_flags;
u32 register_value;
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_U32(acpi_write_bit_register, register_id);
/* Get the info structure corresponding to the requested ACPI Register */
bit_reg_info = acpi_hw_get_bit_register_info(register_id);
if (!bit_reg_info) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
lock_flags = acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock);
/*
* At this point, we know that the parent register is one of the
* following: PM1 Status, PM1 Enable, PM1 Control, or PM2 Control
*/
if (bit_reg_info->parent_register != ACPI_REGISTER_PM1_STATUS) {
/*
* 1) Case for PM1 Enable, PM1 Control, and PM2 Control
*
* Perform a register read to preserve the bits that we are not
* interested in
*/
status = acpi_hw_register_read(bit_reg_info->parent_register,
&register_value);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/*
* Insert the input bit into the value that was just read
* and write the register
*/
ACPI_REGISTER_INSERT_VALUE(register_value,
bit_reg_info->bit_position,
bit_reg_info->access_bit_mask,
value);
status = acpi_hw_register_write(bit_reg_info->parent_register,
register_value);
} else {
/*
* 2) Case for PM1 Status
*
* The Status register is different from the rest. Clear an event
* by writing 1, writing 0 has no effect. So, the only relevant
* information is the single bit we're interested in, all others
* should be written as 0 so they will be left unchanged.
*/
register_value = ACPI_REGISTER_PREPARE_BITS(value,
bit_reg_info->
bit_position,
bit_reg_info->
access_bit_mask);
/* No need to write the register if value is all zeros */
if (register_value) {
status =
acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
register_value);
}
}
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"BitReg %X, ParentReg %X, Value %8.8X, Actual %8.8X\n",
register_id, bit_reg_info->parent_register, value,
register_value));
unlock_and_exit:
acpi_os_release_raw_lock(acpi_gbl_hardware_lock, lock_flags);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_write_bit_register)
#endif /* !ACPI_REDUCED_HARDWARE */
/*******************************************************************************
*
* FUNCTION: acpi_get_sleep_type_data
*
* PARAMETERS: sleep_state - Numeric sleep state
* *sleep_type_a - Where SLP_TYPa is returned
* *sleep_type_b - Where SLP_TYPb is returned
*
* RETURN: Status
*
* DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested
* sleep state via the appropriate \_Sx object.
*
* The sleep state package returned from the corresponding \_Sx_ object
* must contain at least one integer.
*
* March 2005:
* Added support for a package that contains two integers. This
* goes against the ACPI specification which defines this object as a
* package with one encoded DWORD integer. However, existing practice
* by many BIOS vendors is to return a package with 2 or more integer
* elements, at least one per sleep type (A/B).
*
* January 2013:
* Therefore, we must be prepared to accept a package with either a
* single integer or multiple integers.
*
* The single integer DWORD format is as follows:
* BYTE 0 - Value for the PM1A SLP_TYP register
* BYTE 1 - Value for the PM1B SLP_TYP register
* BYTE 2-3 - Reserved
*
* The dual integer format is as follows:
* Integer 0 - Value for the PM1A SLP_TYP register
* Integer 1 - Value for the PM1A SLP_TYP register
*
******************************************************************************/
acpi_status
acpi_get_sleep_type_data(u8 sleep_state, u8 *sleep_type_a, u8 *sleep_type_b)
{
acpi_status status;
struct acpi_evaluate_info *info;
union acpi_operand_object **elements;
ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data);
/* Validate parameters */
if ((sleep_state > ACPI_S_STATES_MAX) || !sleep_type_a || !sleep_type_b) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Allocate the evaluation information block */
info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
if (!info) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/*
* Evaluate the \_Sx namespace object containing the register values
* for this state
*/
info->relative_pathname = acpi_gbl_sleep_state_names[sleep_state];
status = acpi_ns_evaluate(info);
if (ACPI_FAILURE(status)) {
if (status == AE_NOT_FOUND) {
/* The _Sx states are optional, ignore NOT_FOUND */
goto final_cleanup;
}
goto warning_cleanup;
}
/* Must have a return object */
if (!info->return_object) {
ACPI_ERROR((AE_INFO, "No Sleep State object returned from [%s]",
info->relative_pathname));
status = AE_AML_NO_RETURN_VALUE;
goto warning_cleanup;
}
/* Return object must be of type Package */
if (info->return_object->common.type != ACPI_TYPE_PACKAGE) {
ACPI_ERROR((AE_INFO,
"Sleep State return object is not a Package"));
status = AE_AML_OPERAND_TYPE;
goto return_value_cleanup;
}
/*
* Any warnings about the package length or the object types have
* already been issued by the predefined name module -- there is no
* need to repeat them here.
*/
elements = info->return_object->package.elements;
switch (info->return_object->package.count) {
case 0:
status = AE_AML_PACKAGE_LIMIT;
break;
case 1:
if (elements[0]->common.type != ACPI_TYPE_INTEGER) {
status = AE_AML_OPERAND_TYPE;
break;
}
/* A valid _Sx_ package with one integer */
*sleep_type_a = (u8)elements[0]->integer.value;
*sleep_type_b = (u8)(elements[0]->integer.value >> 8);
break;
case 2:
default:
if ((elements[0]->common.type != ACPI_TYPE_INTEGER) ||
(elements[1]->common.type != ACPI_TYPE_INTEGER)) {
status = AE_AML_OPERAND_TYPE;
break;
}
/* A valid _Sx_ package with two integers */
*sleep_type_a = (u8)elements[0]->integer.value;
*sleep_type_b = (u8)elements[1]->integer.value;
break;
}
return_value_cleanup:
acpi_ut_remove_reference(info->return_object);
warning_cleanup:
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"While evaluating Sleep State [%s]",
info->relative_pathname));
}
final_cleanup:
ACPI_FREE(info);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data)