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ACPICA: Update Load() to use operation region interfaces 

Replace memory mapping with region access calls. Now, all region
accesses go through the region handler as they should.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Bob Moore 2009-05-21 10:51:53 +08:00 committed by Len Brown
parent b2f7ddcfcb
commit 3c59f96081
1 changed files with 78 additions and 18 deletions
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96
drivers/acpi/acpica/exconfig.c
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@ -47,6 +47,7 @@
#include "acnamesp.h"
#include "actables.h"
#include "acdispat.h"
#include "acevents.h"
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME("exconfig")
@ -57,6 +58,10 @@ acpi_ex_add_table(u32 table_index,
struct acpi_namespace_node *parent_node,
union acpi_operand_object **ddb_handle);
static acpi_status
acpi_ex_region_read(union acpi_operand_object *obj_desc,
u32 length, u8 *buffer);
/*******************************************************************************
*
* FUNCTION: acpi_ex_add_table
@ -255,6 +260,48 @@ acpi_ex_load_table_op(struct acpi_walk_state *walk_state,
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_region_read
*
* PARAMETERS: obj_desc - Region descriptor
* Length - Number of bytes to read
* Buffer - Pointer to where to put the data
*
* RETURN: Status
*
* DESCRIPTION: Read data from an operation region. The read starts from the
* beginning of the region.
*
******************************************************************************/
static acpi_status
acpi_ex_region_read(union acpi_operand_object *obj_desc, u32 length, u8 *buffer)
{
acpi_status status;
acpi_integer value;
acpi_physical_address address;
u32 i;
address = obj_desc->region.address;
/* Bytewise reads */
for (i = 0; i < length; i++) {
status = acpi_ev_address_space_dispatch(obj_desc, ACPI_READ,
address, 8, &value);
if (ACPI_FAILURE(status)) {
return status;
}
*buffer = (u8)value;
buffer++;
address++;
}
return AE_OK;
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_load_op
@ -317,18 +364,23 @@ acpi_ex_load_op(union acpi_operand_object *obj_desc,
}
}
/*
* Map the table header and get the actual table length. The region
* length is not guaranteed to be the same as the table length.
*/
table = acpi_os_map_memory(obj_desc->region.address,
sizeof(struct acpi_table_header));
/* Get the table header first so we can get the table length */
table = ACPI_ALLOCATE(sizeof(struct acpi_table_header));
if (!table) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
status =
acpi_ex_region_read(obj_desc,
sizeof(struct acpi_table_header),
ACPI_CAST_PTR(u8, table));
length = table->length;
acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
ACPI_FREE(table);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Must have at least an ACPI table header */
@ -337,10 +389,19 @@ acpi_ex_load_op(union acpi_operand_object *obj_desc,
}
/*
* The memory region is not guaranteed to remain stable and we must
* copy the table to a local buffer. For example, the memory region
* is corrupted after suspend on some machines. Dynamically loaded
* tables are usually small, so this overhead is minimal.
* The original implementation simply mapped the table, with no copy.
* However, the memory region is not guaranteed to remain stable and
* we must copy the table to a local buffer. For example, the memory
* region is corrupted after suspend on some machines. Dynamically
* loaded tables are usually small, so this overhead is minimal.
*
* The latest implementation (5/2009) does not use a mapping at all.
* We use the low-level operation region interface to read the table
* instead of the obvious optimization of using a direct mapping.
* This maintains a consistent use of operation regions across the
* entire subsystem. This is important if additional processing must
* be performed in the (possibly user-installed) operation region
* handler. For example, acpi_exec and ASLTS depend on this.
*/
/* Allocate a buffer for the table */
@ -350,17 +411,16 @@ acpi_ex_load_op(union acpi_operand_object *obj_desc,
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Map the entire table and copy it */
/* Read the entire table */
table = acpi_os_map_memory(obj_desc->region.address, length);
if (!table) {
status = acpi_ex_region_read(obj_desc, length,
ACPI_CAST_PTR(u8,
table_desc.pointer));
if (ACPI_FAILURE(status)) {
ACPI_FREE(table_desc.pointer);
return_ACPI_STATUS(AE_NO_MEMORY);
return_ACPI_STATUS(status);
}
ACPI_MEMCPY(table_desc.pointer, table, length);
acpi_os_unmap_memory(table, length);
table_desc.address = obj_desc->region.address;
break;