LXR uboot/lib/acpi/dsdt.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Write the ACPI Differentiated System Description Table (DSDT)
   4 *
   5 * Copyright 2021 Google LLC
   6 */
   7
   8#define LOG_CATEGORY LOGC_ACPI
   9
  10#include <common.h>
  11#include <acpi/acpi_table.h>
  12#include <dm/acpi.h>
  13#include <tables_csum.h>
  14
  15/*
  16 * IASL compiles the dsdt entries and writes the hex values
  17 * to a C array AmlCode[] (see dsdt.c).
  18 */
  19extern const unsigned char AmlCode[];
  20
  21int acpi_write_dsdt(struct acpi_ctx *ctx, const struct acpi_writer *entry)
  22{
  23        const int thl = sizeof(struct acpi_table_header);
  24        struct acpi_table_header *dsdt = ctx->current;
  25        int aml_len;
  26
  27        /* Put the table header first */
  28        memcpy(dsdt, &AmlCode, thl);
  29        acpi_inc(ctx, thl);
  30        log_debug("DSDT starts at %p, hdr ends at %p\n", dsdt, ctx->current);
  31
  32        /* If the table is not empty, allow devices to inject things */
  33        aml_len = dsdt->length - thl;
  34        if (aml_len) {
  35                void *base = ctx->current;
  36                int ret;
  37
  38                ret = acpi_inject_dsdt(ctx);
  39                if (ret)
  40                        return log_msg_ret("inject", ret);
  41                log_debug("Added %lx bytes from inject_dsdt, now at %p\n",
  42                          (ulong)(ctx->current - base), ctx->current);
  43                log_debug("Copy AML code size %x to %p\n", aml_len,
  44                          ctx->current);
  45                memcpy(ctx->current, AmlCode + thl, aml_len);
  46                acpi_inc(ctx, aml_len);
  47        }
  48
  49        ctx->dsdt = dsdt;
  50        dsdt->length = ctx->current - (void *)dsdt;
  51        log_debug("Updated DSDT length to %x\n", dsdt->length);
  52
  53        return 0;
  54}
  55ACPI_WRITER(3dsdt, "DSDT", acpi_write_dsdt, 0);
  56