u-boot-brain/lib/acpi/acpigen.c
Simon Glass 3df33bda5c acpi: Support writing a string
ACPI supports storing a simple null-terminated string. Add support for
this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-07-17 14:32:24 +08:00

156 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Generation of ACPI (Advanced Configuration and Power Interface) tables
*
* Copyright 2019 Google LLC
* Mostly taken from coreboot
*/
#define LOG_CATEGORY LOGC_ACPI
#include <common.h>
#include <dm.h>
#include <log.h>
#include <acpi/acpigen.h>
#include <dm/acpi.h>
u8 *acpigen_get_current(struct acpi_ctx *ctx)
{
return ctx->current;
}
void acpigen_emit_byte(struct acpi_ctx *ctx, uint data)
{
*(u8 *)ctx->current++ = data;
}
void acpigen_emit_word(struct acpi_ctx *ctx, uint data)
{
acpigen_emit_byte(ctx, data & 0xff);
acpigen_emit_byte(ctx, (data >> 8) & 0xff);
}
void acpigen_emit_dword(struct acpi_ctx *ctx, uint data)
{
/* Output the value in little-endian format */
acpigen_emit_byte(ctx, data & 0xff);
acpigen_emit_byte(ctx, (data >> 8) & 0xff);
acpigen_emit_byte(ctx, (data >> 16) & 0xff);
acpigen_emit_byte(ctx, (data >> 24) & 0xff);
}
/*
* Maximum length for an ACPI object generated by this code,
*
* If you need to change this, change acpigen_write_len_f(ctx) and
* acpigen_pop_len(ctx)
*/
#define ACPIGEN_MAXLEN 0xfffff
void acpigen_write_len_f(struct acpi_ctx *ctx)
{
assert(ctx->ltop < (ACPIGEN_LENSTACK_SIZE - 1));
ctx->len_stack[ctx->ltop++] = ctx->current;
acpigen_emit_byte(ctx, 0);
acpigen_emit_byte(ctx, 0);
acpigen_emit_byte(ctx, 0);
}
void acpigen_pop_len(struct acpi_ctx *ctx)
{
int len;
char *p;
assert(ctx->ltop > 0);
p = ctx->len_stack[--ctx->ltop];
len = ctx->current - (void *)p;
assert(len <= ACPIGEN_MAXLEN);
/* generate store length for 0xfffff max */
p[0] = ACPI_PKG_LEN_3_BYTES | (len & 0xf);
p[1] = len >> 4 & 0xff;
p[2] = len >> 12 & 0xff;
}
char *acpigen_write_package(struct acpi_ctx *ctx, int nr_el)
{
char *p;
acpigen_emit_byte(ctx, PACKAGE_OP);
acpigen_write_len_f(ctx);
p = ctx->current;
acpigen_emit_byte(ctx, nr_el);
return p;
}
void acpigen_write_byte(struct acpi_ctx *ctx, unsigned int data)
{
acpigen_emit_byte(ctx, BYTE_PREFIX);
acpigen_emit_byte(ctx, data & 0xff);
}
void acpigen_write_word(struct acpi_ctx *ctx, unsigned int data)
{
acpigen_emit_byte(ctx, WORD_PREFIX);
acpigen_emit_word(ctx, data);
}
void acpigen_write_dword(struct acpi_ctx *ctx, unsigned int data)
{
acpigen_emit_byte(ctx, DWORD_PREFIX);
acpigen_emit_dword(ctx, data);
}
void acpigen_write_qword(struct acpi_ctx *ctx, u64 data)
{
acpigen_emit_byte(ctx, QWORD_PREFIX);
acpigen_emit_dword(ctx, data & 0xffffffff);
acpigen_emit_dword(ctx, (data >> 32) & 0xffffffff);
}
void acpigen_write_zero(struct acpi_ctx *ctx)
{
acpigen_emit_byte(ctx, ZERO_OP);
}
void acpigen_write_one(struct acpi_ctx *ctx)
{
acpigen_emit_byte(ctx, ONE_OP);
}
void acpigen_write_integer(struct acpi_ctx *ctx, u64 data)
{
if (data == 0)
acpigen_write_zero(ctx);
else if (data == 1)
acpigen_write_one(ctx);
else if (data <= 0xff)
acpigen_write_byte(ctx, (unsigned char)data);
else if (data <= 0xffff)
acpigen_write_word(ctx, (unsigned int)data);
else if (data <= 0xffffffff)
acpigen_write_dword(ctx, (unsigned int)data);
else
acpigen_write_qword(ctx, data);
}
void acpigen_emit_stream(struct acpi_ctx *ctx, const char *data, int size)
{
int i;
for (i = 0; i < size; i++)
acpigen_emit_byte(ctx, data[i]);
}
void acpigen_emit_string(struct acpi_ctx *ctx, const char *str)
{
acpigen_emit_stream(ctx, str, str ? strlen(str) : 0);
acpigen_emit_byte(ctx, '\0');
}
void acpigen_write_string(struct acpi_ctx *ctx, const char *str)
{
acpigen_emit_byte(ctx, STRING_PREFIX);
acpigen_emit_string(ctx, str);
}