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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Core ACPI (Advanced Configuration and Power Interface) support
*
* Copyright 2019 Google LLC
*
* Modified from coreboot file acpigen.h
*/
#ifndef __ACPI_ACPIGEN_H
#define __ACPI_ACPIGEN_H
#include <linux/types.h>
struct acpi_ctx;
/* Top 4 bits of the value used to indicate a three-byte length value */
#define ACPI_PKG_LEN_3_BYTES 0x80
/* ACPI Op/Prefix codes */
enum {
ZERO_OP = 0x00,
ONE_OP = 0x01,
NAME_OP = 0x08,
BYTE_PREFIX = 0x0a,
WORD_PREFIX = 0x0b,
DWORD_PREFIX = 0x0c,
STRING_PREFIX = 0x0d,
QWORD_PREFIX = 0x0e,
BUFFER_OP = 0x11,
PACKAGE_OP = 0x12,
DUAL_NAME_PREFIX = 0x2e,
MULTI_NAME_PREFIX = 0x2f,
};
/**
* acpigen_get_current() - Get the current ACPI code output pointer
*
* @ctx: ACPI context pointer
* @return output pointer
*/
u8 *acpigen_get_current(struct acpi_ctx *ctx);
/**
* acpigen_emit_byte() - Emit a byte to the ACPI code
*
* @ctx: ACPI context pointer
* @data: Value to output
*/
void acpigen_emit_byte(struct acpi_ctx *ctx, uint data);
/**
* acpigen_emit_word() - Emit a 16-bit word to the ACPI code
*
* @ctx: ACPI context pointer
* @data: Value to output
*/
void acpigen_emit_word(struct acpi_ctx *ctx, uint data);
/**
* acpigen_emit_dword() - Emit a 32-bit 'double word' to the ACPI code
*
* @ctx: ACPI context pointer
* @data: Value to output
*/
void acpigen_emit_dword(struct acpi_ctx *ctx, uint data);
/**
* acpigen_emit_stream() - Emit a stream of bytes
*
* @ctx: ACPI context pointer
* @data: Data to output
* @size: Size of data in bytes
*/
void acpigen_emit_stream(struct acpi_ctx *ctx, const char *data, int size);
/**
* acpigen_emit_string() - Emit a string
*
* Emit a string with a null terminator
*
* @ctx: ACPI context pointer
* @str: String to output, or NULL for an empty string
*/
void acpigen_emit_string(struct acpi_ctx *ctx, const char *str);
/**
* acpigen_write_len_f() - Write a 'forward' length placeholder
*
* This adds space for a length value in the ACPI stream and pushes the current
* position (before the length) on the stack. After calling this you can write
* some data and then call acpigen_pop_len() to update the length value.
*
* Usage:
*
* acpigen_write_len_f() ------\
* acpigen_write...() |
* acpigen_write...() |
* acpigen_write_len_f() --\ |
* acpigen_write...() | |
* acpigen_write...() | |
* acpigen_pop_len() ------/ |
* acpigen_write...() |
* acpigen_pop_len() ----------/
*
* See ACPI 6.3 section 20.2.4 Package Length Encoding
*
* This implementation always uses a 3-byte packet length for simplicity. It
* could be adjusted to support other lengths.
*
* @ctx: ACPI context pointer
*/
void acpigen_write_len_f(struct acpi_ctx *ctx);
/**
* acpigen_pop_len() - Update the previously stacked length placeholder
*
* Call this after the data for the block has been written. It updates the
* top length value in the stack and pops it off.
*
* @ctx: ACPI context pointer
*/
void acpigen_pop_len(struct acpi_ctx *ctx);
/**
* acpigen_write_package() - Start writing a package
*
* A package collects together a number of elements in the ACPI code. To write
* a package use:
*
* acpigen_write_package(ctx, 3);
* ...write things
* acpigen_pop_len()
*
* If you don't know the number of elements in advance, acpigen_write_package()
* returns a pointer to the value so you can update it later:
*
* char *num_elements = acpigen_write_package(ctx, 0);
* ...write things
* *num_elements += 1;
* ...write things
* *num_elements += 1;
* acpigen_pop_len()
*
* @ctx: ACPI context pointer
* @nr_el: Number of elements (0 if not known)
* @returns pointer to the number of elements, which can be updated by the
* caller if needed
*/
char *acpigen_write_package(struct acpi_ctx *ctx, int nr_el);
/**
* acpigen_write_integer() - Write an integer
*
* This writes an operation (BYTE_OP, WORD_OP, DWORD_OP, QWORD_OP depending on
* the integer size) and an integer value. Note that WORD means 16 bits in ACPI.
*
* @ctx: ACPI context pointer
* @data: Integer to write
*/
void acpigen_write_integer(struct acpi_ctx *ctx, u64 data);
/**
* acpigen_write_string() - Write a string
*
* This writes a STRING_PREFIX followed by a null-terminated string
*
* @ctx: ACPI context pointer
* @str: String to write
*/
void acpigen_write_string(struct acpi_ctx *ctx, const char *str);
/**
* acpigen_emit_namestring() - Emit an ACPI name
*
* This writes out an ACPI name or path in the required special format. It does
* not add the NAME_OP prefix.
*
* @ctx: ACPI context pointer
* @namepath: Name / path to emit
*/
void acpigen_emit_namestring(struct acpi_ctx *ctx, const char *namepath);
/**
* acpigen_write_name() - Write out an ACPI name
*
* This writes out an ACPI name or path in the required special format with a
* NAME_OP prefix.
*
* @ctx: ACPI context pointer
* @namepath: Name / path to emit
*/
void acpigen_write_name(struct acpi_ctx *ctx, const char *namepath);
/**
* acpigen_write_uuid() - Write a UUID
*
* This writes out a UUID in the format used by ACPI, with a BUFFER_OP prefix.
*
* @ctx: ACPI context pointer
* @uuid: UUID to write in the form aabbccdd-eeff-gghh-iijj-kkllmmnnoopp
* @return 0 if OK, -EINVAL if the format is incorrect
*/
int acpigen_write_uuid(struct acpi_ctx *ctx, const char *uuid);
#endif