src/arch/i386/boot/acpi.c

   1 /*
   2  * LinuxBIOS ACPI Table support
   3  * written by Stefan Reinauer <stepan@openbios.org>
   4  * (C) 2004 SUSE LINUX AG
   5  */
   6
   7 #include <console/console.h>
   8 #include <string.h>
   9 #include <arch/acpi.h>
  10
  11 #define RSDP_SIG              "RSD PTR "  /* RSDT Pointer signature */
  12 #define RSDP_NAME             "RSDP"
  13
  14 #define RSDT_NAME             "RSDT"
  15 #define HPET_NAME             "HPET"
  16 #define RSDT_TABLE            "  RSDT  "
  17 #define HPET_TABLE            "AMD64   "
  18
  19 #define OEM_ID                "LXBIOS"
  20 #define ASLC                  "NONE"
  21
  22 static u8 acpi_checksum(u8 *table, u32 length)
  23 {
  24         u8 ret=0;
  25         while (length--) {
  26                 ret += *table;
  27                 table++;
  28         }
  29         return ret;
  30 }
  31
  32 static void acpi_add_table(acpi_rsdt_t *rsdt, void *table)
  33 {
  34         int i;
  35
  36         for (i=0; i<8; i++) {
  37                 if(rsdt->entry[i]==0) {
  38                         rsdt->entry[i]=(u32)table;
  39                         /* fix checksum */
  40                         /* hope this won't get optimized away */
  41                         rsdt->header.checksum=0;
  42                         rsdt->header.checksum=acpi_checksum((u8 *)rsdt,
  43                                         rsdt->header.length);
  44
  45                         printk_debug("ACPI: added table %d/8\n",i);
  46                         return;
  47                 }
  48         }
  49
  50         printk_warning("ACPI: could not ACPI table. failed.\n");
  51 }
  52
  53 static void acpi_create_hpet(acpi_hpet_t *hpet)
  54 {
  55 #define HPET_ADDR  0xfed00000ULL
  56         acpi_header_t *header=&(hpet->header);
  57         acpi_addr_t *addr=&(hpet->addr);
  58
  59         /* fill out header fields */
  60         memcpy(header->signature, HPET_NAME, 4);
  61         memcpy(header->oem_id, OEM_ID, 6);
  62         memcpy(header->oem_table_id, HPET_TABLE, 8);
  63         memcpy(header->asl_compiler_id, ASLC, 4);
  64
  65         header->length = sizeof(acpi_hpet_t);
  66         header->revision = 1;
  67
  68         /* fill out HPET address */
  69         addr->space_id          = 0; /* Memory */
  70         addr->bit_width         = 64;
  71         addr->bit_offset        = 0;
  72         addr->addrl             = HPET_ADDR & 0xffffffff;
  73         addr->addrh             = HPET_ADDR >> 32;
  74
  75         hpet->id        = 0x102282a0; /* AMD ? */
  76         hpet->number    = 0;
  77         hpet->min_tick  = 4096;
  78
  79 }
  80
  81 static void acpi_write_rsdt(acpi_rsdt_t *rsdt)
  82 {
  83         acpi_header_t *header=&(rsdt->header);
  84
  85         /* fill out header fields */
  86         memcpy(header->signature, RSDT_NAME, 4);
  87         memcpy(header->oem_id, OEM_ID, 6);
  88         memcpy(header->oem_table_id, RSDT_TABLE, 8);
  89         memcpy(header->asl_compiler_id, ASLC, 4);
  90
  91         header->length = sizeof(acpi_rsdt_t);
  92         header->revision = 1;
  93
  94         /* fill out entries */
  95
  96         // entries are filled in later, we come with an empty set.
  97
  98         /* fix checksum */
  99
 100         header->checksum        = acpi_checksum((void *)rsdt, sizeof(acpi_rsdt_t));
 101 }
 102
 103 static void acpi_write_rsdp(acpi_rsdp_t *rsdp, acpi_rsdt_t *rsdt)
 104 {
 105         memcpy(rsdp->signature, RSDP_SIG, 8);
 106         memcpy(rsdp->oem_id, OEM_ID, 6);
 107
 108         rsdp->length            = sizeof(acpi_rsdp_t);
 109         rsdp->rsdt_address      = (u32)rsdt;
 110         rsdp->checksum          = acpi_checksum((void *)rsdp, sizeof(acpi_rsdp_t));
 111
 112 }
 113
 114 unsigned long write_acpi_tables(unsigned long start)
 115 {
 116         unsigned long current = start;
 117         acpi_rsdp_t *rsdp;
 118         acpi_rsdt_t *rsdt;
 119         acpi_hpet_t *hpet;
 120
 121         printk_info("ACPI: Writing ACPI tables at %lx...\n", start);
 122
 123         /* We need at least an RSDP and an RSDT Table */
 124         rsdp = (acpi_rsdp_t *) current;
 125         current += sizeof(acpi_rsdp_t);
 126         rsdt = (acpi_rsdt_t *) current;
 127         current += sizeof(acpi_rsdt_t);
 128
 129         /* clear all table memory */
 130         memset((void *)start, 0, current - start);
 131
 132         acpi_write_rsdp(rsdp, rsdt);
 133         acpi_write_rsdt(rsdt);
 134
 135         /*
 136          * We explicitly add these tables later on:
 137          */
 138 #define HAVE_ACPI_HPET
 139 #ifdef HAVE_ACPI_HPET
 140         printk_debug("ACPI:    * HPET\n");
 141
 142         hpet = (acpi_hpet_t *) current;
 143         current += sizeof(acpi_hpet_t);
 144
 145         acpi_create_hpet(hpet);
 146         acpi_add_table(rsdt,hpet);
 147 #endif
 148         printk_info("ACPI: done.\n");
 149         return current;
 150 }
 151