LXR uboot/lib/acpi/ssdt.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Write an ACPI Secondary System Descriptor Table (SSDT) table
   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
  15int acpi_write_ssdt(struct acpi_ctx *ctx, const struct acpi_writer *entry)
  16{
  17        struct acpi_table_header *ssdt;
  18        int ret;
  19
  20        ssdt = ctx->current;
  21        memset((void *)ssdt, '\0', sizeof(struct acpi_table_header));
  22
  23        acpi_fill_header(ssdt, "SSDT");
  24        memcpy(ssdt->oem_table_id, OEM_TABLE_ID, sizeof(ssdt->oem_table_id));
  25        ssdt->revision = acpi_get_table_revision(ACPITAB_SSDT);
  26        ssdt->aslc_revision = 1;
  27        ssdt->length = sizeof(struct acpi_table_header);
  28
  29        acpi_inc(ctx, sizeof(struct acpi_table_header));
  30
  31        ret = acpi_fill_ssdt(ctx);
  32        if (ret) {
  33                ctx->current = ssdt;
  34                return log_msg_ret("fill", ret);
  35        }
  36
  37        /* (Re)calculate length and checksum */
  38        ssdt->length = ctx->current - (void *)ssdt;
  39        ssdt->checksum = table_compute_checksum((void *)ssdt, ssdt->length);
  40        log_debug("SSDT at %p, length %x\n", ssdt, ssdt->length);
  41
  42        /* Drop the table if it is empty */
  43        if (ssdt->length == sizeof(struct acpi_table_header))
  44                return log_msg_ret("fill", -ENOENT);
  45        acpi_add_table(ctx, ssdt);
  46
  47        return 0;
  48}
  49ACPI_WRITER(6ssdt, "SSDT", acpi_write_ssdt, 0);
  50