exconvrt.c
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: exconvrt - Object conversion routines
*
* Copyright (C) 2000 - 2019, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acinterp.h"
#include "amlcode.h"
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME("exconvrt")
/* Local prototypes */
static u32
acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 max_length);
/*******************************************************************************
*
* FUNCTION: acpi_ex_convert_to_integer
*
* PARAMETERS: obj_desc - Object to be converted. Must be an
* Integer, Buffer, or String
* result_desc - Where the new Integer object is returned
* implicit_conversion - Used for string conversion
*
* RETURN: Status
*
* DESCRIPTION: Convert an ACPI Object to an integer.
*
******************************************************************************/
acpi_status
acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
union acpi_operand_object **result_desc,
u32 implicit_conversion)
{
union acpi_operand_object *return_desc;
u8 *pointer;
u64 result;
u32 i;
u32 count;
ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
switch (obj_desc->common.type) {
case ACPI_TYPE_INTEGER:
/* No conversion necessary */
*result_desc = obj_desc;
return_ACPI_STATUS(AE_OK);
case ACPI_TYPE_BUFFER:
case ACPI_TYPE_STRING:
/* Note: Takes advantage of common buffer/string fields */
pointer = obj_desc->buffer.pointer;
count = obj_desc->buffer.length;
break;
default:
return_ACPI_STATUS(AE_TYPE);
}
/*
* Convert the buffer/string to an integer. Note that both buffers and
* strings are treated as raw data - we don't convert ascii to hex for
* strings.
*
* There are two terminating conditions for the loop:
* 1) The size of an integer has been reached, or
* 2) The end of the buffer or string has been reached
*/
result = 0;
/* String conversion is different than Buffer conversion */
switch (obj_desc->common.type) {
case ACPI_TYPE_STRING:
/*
* Convert string to an integer - for most cases, the string must be
* hexadecimal as per the ACPI specification. The only exception (as
* of ACPI 3.0) is that the to_integer() operator allows both decimal
* and hexadecimal strings (hex prefixed with "0x").
*
* Explicit conversion is used only by to_integer.
* All other string-to-integer conversions are implicit conversions.
*/
if (implicit_conversion) {
result =
acpi_ut_implicit_strtoul64(ACPI_CAST_PTR
(char, pointer));
} else {
result =
acpi_ut_explicit_strtoul64(ACPI_CAST_PTR
(char, pointer));
}
break;
case ACPI_TYPE_BUFFER:
/* Check for zero-length buffer */
if (!count) {
return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
}
/* Transfer no more than an integer's worth of data */
if (count > acpi_gbl_integer_byte_width) {
count = acpi_gbl_integer_byte_width;
}
/*
* Convert buffer to an integer - we simply grab enough raw data
* from the buffer to fill an integer
*/
for (i = 0; i < count; i++) {
/*
* Get next byte and shift it into the Result.
* Little endian is used, meaning that the first byte of the buffer
* is the LSB of the integer
*/
result |= (((u64) pointer[i]) << (i * 8));
}
break;
default:
/* No other types can get here */
break;
}
/* Create a new integer */
return_desc = acpi_ut_create_integer_object(result);
if (!return_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
ACPI_FORMAT_UINT64(result)));
/* Save the Result */
(void)acpi_ex_truncate_for32bit_table(return_desc);
*result_desc = return_desc;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_convert_to_buffer
*
* PARAMETERS: obj_desc - Object to be converted. Must be an
* Integer, Buffer, or String
* result_desc - Where the new buffer object is returned
*
* RETURN: Status
*
* DESCRIPTION: Convert an ACPI Object to a Buffer
*
******************************************************************************/
acpi_status
acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
union acpi_operand_object **result_desc)
{
union acpi_operand_object *return_desc;
u8 *new_buf;
ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
switch (obj_desc->common.type) {
case ACPI_TYPE_BUFFER:
/* No conversion necessary */
*result_desc = obj_desc;
return_ACPI_STATUS(AE_OK);
case ACPI_TYPE_INTEGER:
/*
* Create a new Buffer object.
* Need enough space for one integer
*/
return_desc =
acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
if (!return_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Copy the integer to the buffer, LSB first */
new_buf = return_desc->buffer.pointer;
memcpy(new_buf, &obj_desc->integer.value,
acpi_gbl_integer_byte_width);
break;
case ACPI_TYPE_STRING:
/*
* Create a new Buffer object
* Size will be the string length
*
* NOTE: Add one to the string length to include the null terminator.
* The ACPI spec is unclear on this subject, but there is existing
* ASL/AML code that depends on the null being transferred to the new
* buffer.
*/
return_desc = acpi_ut_create_buffer_object((acpi_size)
obj_desc->string.
length + 1);
if (!return_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Copy the string to the buffer */
new_buf = return_desc->buffer.pointer;
strncpy((char *)new_buf, (char *)obj_desc->string.pointer,
obj_desc->string.length);
break;
default:
return_ACPI_STATUS(AE_TYPE);
}
/* Mark buffer initialized */
return_desc->common.flags |= AOPOBJ_DATA_VALID;
*result_desc = return_desc;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_convert_to_ascii
*
* PARAMETERS: integer - Value to be converted
* base - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
* string - Where the string is returned
* data_width - Size of data item to be converted, in bytes
*
* RETURN: Actual string length
*
* DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
*
******************************************************************************/
static u32
acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 data_width)
{
u64 digit;
u32 i;
u32 j;
u32 k = 0;
u32 hex_length;
u32 decimal_length;
u32 remainder;
u8 supress_zeros;
ACPI_FUNCTION_ENTRY();
switch (base) {
case 10:
/* Setup max length for the decimal number */
switch (data_width) {
case 1:
decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
break;
case 4:
decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
break;
case 8:
default:
decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
break;
}
supress_zeros = TRUE; /* No leading zeros */
remainder = 0;
for (i = decimal_length; i > 0; i--) {
/* Divide by nth factor of 10 */
digit = integer;
for (j = 0; j < i; j++) {
(void)acpi_ut_short_divide(digit, 10, &digit,
&remainder);
}
/* Handle leading zeros */
if (remainder != 0) {
supress_zeros = FALSE;
}
if (!supress_zeros) {
string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
k++;
}
}
break;
case 16:
/* hex_length: 2 ascii hex chars per data byte */
hex_length = (data_width * 2);
for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
/* Get one hex digit, most significant digits first */
string[k] = (u8)
acpi_ut_hex_to_ascii_char(integer, ACPI_MUL_4(j));
k++;
}
break;
default:
return (0);
}
/*
* Since leading zeros are suppressed, we must check for the case where
* the integer equals 0
*
* Finally, null terminate the string and return the length
*/
if (!k) {
string[0] = ACPI_ASCII_ZERO;
k = 1;
}
string[k] = 0;
return ((u32) k);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_convert_to_string
*
* PARAMETERS: obj_desc - Object to be converted. Must be an
* Integer, Buffer, or String
* result_desc - Where the string object is returned
* type - String flags (base and conversion type)
*
* RETURN: Status
*
* DESCRIPTION: Convert an ACPI Object to a string. Supports both implicit
* and explicit conversions and related rules.
*
******************************************************************************/
acpi_status
acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
union acpi_operand_object ** result_desc, u32 type)
{
union acpi_operand_object *return_desc;
u8 *new_buf;
u32 i;
u32 string_length = 0;
u16 base = 16;
u8 separator = ',';
ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
switch (obj_desc->common.type) {
case ACPI_TYPE_STRING:
/* No conversion necessary */
*result_desc = obj_desc;
return_ACPI_STATUS(AE_OK);
case ACPI_TYPE_INTEGER:
switch (type) {
case ACPI_EXPLICIT_CONVERT_DECIMAL:
/*
* From to_decimal_string, integer source.
*
* Make room for the maximum decimal number size
*/
string_length = ACPI_MAX_DECIMAL_DIGITS;
base = 10;
break;
default:
/* Two hex string characters for each integer byte */
string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
break;
}
/*
* Create a new String
* Need enough space for one ASCII integer (plus null terminator)
*/
return_desc =
acpi_ut_create_string_object((acpi_size)string_length);
if (!return_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
new_buf = return_desc->buffer.pointer;
/* Convert integer to string */
string_length =
acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
new_buf,
acpi_gbl_integer_byte_width);
/* Null terminate at the correct place */
return_desc->string.length = string_length;
new_buf[string_length] = 0;
break;
case ACPI_TYPE_BUFFER:
/* Setup string length, base, and separator */
switch (type) {
case ACPI_EXPLICIT_CONVERT_DECIMAL: /* Used by to_decimal_string */
/*
* Explicit conversion from the to_decimal_string ASL operator.
*
* From ACPI: "If the input is a buffer, it is converted to a
* a string of decimal values separated by commas."
*/
base = 10;
/*
* Calculate the final string length. Individual string values
* are variable length (include separator for each)
*/
for (i = 0; i < obj_desc->buffer.length; i++) {
if (obj_desc->buffer.pointer[i] >= 100) {
string_length += 4;
} else if (obj_desc->buffer.pointer[i] >= 10) {
string_length += 3;
} else {
string_length += 2;
}
}
break;
case ACPI_IMPLICIT_CONVERT_HEX:
/*
* Implicit buffer-to-string conversion
*
* From the ACPI spec:
* "The entire contents of the buffer are converted to a string of
* two-character hexadecimal numbers, each separated by a space."
*
* Each hex number is prefixed with 0x (11/2018)
*/
separator = ' ';
string_length = (obj_desc->buffer.length * 5);
break;
case ACPI_EXPLICIT_CONVERT_HEX:
/*
* Explicit conversion from the to_hex_string ASL operator.
*
* From ACPI: "If Data is a buffer, it is converted to a string of
* hexadecimal values separated by commas."
*
* Each hex number is prefixed with 0x (11/2018)
*/
separator = ',';
string_length = (obj_desc->buffer.length * 5);
break;
default:
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/*
* Create a new string object and string buffer
* (-1 because of extra separator included in string_length from above)
* Allow creation of zero-length strings from zero-length buffers.
*/
if (string_length) {
string_length--;
}
return_desc =
acpi_ut_create_string_object((acpi_size)string_length);
if (!return_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
new_buf = return_desc->buffer.pointer;
/*
* Convert buffer bytes to hex or decimal values
* (separated by commas or spaces)
*/
for (i = 0; i < obj_desc->buffer.length; i++) {
if (base == 16) {
/* Emit 0x prefix for explicit/implicit hex conversion */
*new_buf++ = '0';
*new_buf++ = 'x';
}
new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
buffer.pointer[i],
base, new_buf, 1);
/* Each digit is separated by either a comma or space */
*new_buf++ = separator;
}
/*
* Null terminate the string
* (overwrites final comma/space from above)
*/
if (obj_desc->buffer.length) {
new_buf--;
}
*new_buf = 0;
break;
default:
return_ACPI_STATUS(AE_TYPE);
}
*result_desc = return_desc;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_convert_to_target_type
*
* PARAMETERS: destination_type - Current type of the destination
* source_desc - Source object to be converted.
* result_desc - Where the converted object is returned
* walk_state - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Implements "implicit conversion" rules for storing an object.
*
******************************************************************************/
acpi_status
acpi_ex_convert_to_target_type(acpi_object_type destination_type,
union acpi_operand_object *source_desc,
union acpi_operand_object **result_desc,
struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
/* Default behavior */
*result_desc = source_desc;
/*
* If required by the target,
* perform implicit conversion on the source before we store it.
*/
switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
case ARGI_SIMPLE_TARGET:
case ARGI_FIXED_TARGET:
case ARGI_INTEGER_REF: /* Handles Increment, Decrement cases */
switch (destination_type) {
case ACPI_TYPE_LOCAL_REGION_FIELD:
/*
* Named field can always handle conversions
*/
break;
default:
/* No conversion allowed for these types */
if (destination_type != source_desc->common.type) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Explicit operator, will store (%s) over existing type (%s)\n",
acpi_ut_get_object_type_name
(source_desc),
acpi_ut_get_type_name
(destination_type)));
status = AE_TYPE;
}
}
break;
case ARGI_TARGETREF:
case ARGI_STORE_TARGET:
switch (destination_type) {
case ACPI_TYPE_INTEGER:
case ACPI_TYPE_BUFFER_FIELD:
case ACPI_TYPE_LOCAL_BANK_FIELD:
case ACPI_TYPE_LOCAL_INDEX_FIELD:
/*
* These types require an Integer operand. We can convert
* a Buffer or a String to an Integer if necessary.
*/
status =
acpi_ex_convert_to_integer(source_desc, result_desc,
ACPI_IMPLICIT_CONVERSION);
break;
case ACPI_TYPE_STRING:
/*
* The operand must be a String. We can convert an
* Integer or Buffer if necessary
*/
status =
acpi_ex_convert_to_string(source_desc, result_desc,
ACPI_IMPLICIT_CONVERT_HEX);
break;
case ACPI_TYPE_BUFFER:
/*
* The operand must be a Buffer. We can convert an
* Integer or String if necessary
*/
status =
acpi_ex_convert_to_buffer(source_desc, result_desc);
break;
default:
ACPI_ERROR((AE_INFO,
"Bad destination type during conversion: 0x%X",
destination_type));
status = AE_AML_INTERNAL;
break;
}
break;
case ARGI_REFERENCE:
/*
* create_xxxx_field cases - we are storing the field object into the name
*/
break;
default:
ACPI_ERROR((AE_INFO,
"Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
GET_CURRENT_ARG_TYPE(walk_state->op_info->
runtime_args),
walk_state->opcode,
acpi_ut_get_type_name(destination_type)));
status = AE_AML_INTERNAL;
}
/*
* Source-to-Target conversion semantics:
*
* If conversion to the target type cannot be performed, then simply
* overwrite the target with the new object and type.
*/
if (status == AE_TYPE) {
status = AE_OK;
}
return_ACPI_STATUS(status);
}