src/acpi/gnvs.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <acpi/acpi_gnvs.h>
   4 #include <acpi/acpigen.h>
   5 #include <cbmem.h>
   6 #include <console/console.h>
   7 #include <string.h>
   8 #include <types.h>
   9
  10 static void *gnvs;
  11
  12 void *acpi_get_gnvs(void)
  13 {
  14         if (gnvs)
  15                 return gnvs;
  16
  17         gnvs = cbmem_find(CBMEM_ID_ACPI_GNVS);
  18         if (gnvs)
  19                 return gnvs;
  20
  21         printk(BIOS_ERR, "Unable to locate Global NVS\n");
  22         return NULL;
  23 }
  24
  25 static void gnvs_assign_cbmc(void)
  26 {
  27         uint32_t *gnvs_cbmc = gnvs_cbmc_ptr();
  28         if (gnvs_cbmc)
  29                 *gnvs_cbmc = (uintptr_t)cbmem_find(CBMEM_ID_CONSOLE);
  30 }
  31
  32 void *gnvs_get_or_create(void)
  33 {
  34         size_t gnvs_size;
  35
  36         if (gnvs)
  37                 return gnvs;
  38
  39         gnvs = cbmem_find(CBMEM_ID_ACPI_GNVS);
  40         if (gnvs)
  41                 return gnvs;
  42
  43         gnvs_size = gnvs_size_of_array();
  44
  45         gnvs = cbmem_add(CBMEM_ID_ACPI_GNVS, gnvs_size);
  46         if (!gnvs)
  47                 return gnvs;
  48
  49         memset(gnvs, 0, gnvs_size);
  50
  51         if (CONFIG(CONSOLE_CBMEM))
  52                 gnvs_assign_cbmc();
  53
  54         if (CONFIG(CHROMEOS))
  55                 gnvs_assign_chromeos();
  56
  57         return gnvs;
  58 }
  59
  60 void acpi_inject_nvsa(void)
  61 {
  62         uintptr_t gnvs_address = (uintptr_t)acpi_get_gnvs();
  63         if (!gnvs_address)
  64                 return;
  65
  66         acpigen_write_scope("\\");
  67         acpigen_write_name_dword("NVSA", gnvs_address);
  68         acpigen_pop_len();
  69 }