Rev 29 | Rev 33 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 29 | jermar | 1 | /* |
| 2 | * Copyright (C) 2005 Jakub Jermar |
||
| 3 | * All rights reserved. |
||
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | #include <arch/acpi/acpi.h> |
||
| 32 | jermar | 30 | #include <arch/bios/bios.h> |
| 29 | jermar | 31 | |
| 32 | jermar | 32 | #define RSDP_SIGNATURE "RSD PTR " |
| 33 | #define RSDP_REVISION_OFFS 15 |
||
| 34 | |||
| 29 | jermar | 35 | struct acpi_rsdp *acpi_rsdp = NULL; |
| 36 | |||
| 32 | jermar | 37 | int rsdp_check(__u8 *rsdp) { |
| 38 | struct acpi_rsdp *r = (struct acpi_rsdp *) rsdp; |
||
| 39 | __u8 sum = 0; |
||
| 40 | int i; |
||
| 41 | |||
| 42 | for (i=0; i<20; i++) |
||
| 43 | sum += rsdp[i]; |
||
| 44 | |||
| 45 | if (sum) |
||
| 46 | return 0; /* bad checksum */ |
||
| 47 | |||
| 48 | if (r->revision == 0) |
||
| 49 | return 1; /* ACPI 1.0 */ |
||
| 50 | |||
| 51 | for (; i<r->length; i++) |
||
| 52 | sum += rsdp[i]; |
||
| 53 | |||
| 54 | return !sum; |
||
| 55 | |||
| 56 | } |
||
| 57 | |||
| 29 | jermar | 58 | void acpi_init(void) |
| 59 | { |
||
| 32 | jermar | 60 | __u8 *addr[2] = { NULL, (__u8 *) 0xe0000 }; |
| 61 | int i, j, length[2] = { 1024, 128*1024 }; |
||
| 62 | __u64 *sig = (__u64 *) RSDP_SIGNATURE; |
||
| 63 | |||
| 64 | /* |
||
| 65 | * Find Root System Description Pointer |
||
| 66 | * 1. search first 1K of EBDA |
||
| 67 | * 2. search 128K starting at 0xe0000 |
||
| 68 | */ |
||
| 69 | |||
| 70 | addr[0] = (__u8 *) ebda; |
||
| 71 | for (i = (ebda ? 0 : 1); i < 2; i++) { |
||
| 72 | for (j = 0; j < length[i]; j += 16) { |
||
| 73 | if (*((__u64 *) &addr[i][j]) == *sig && rsdp_check(&addr[i][j])) { |
||
| 74 | acpi_rsdp = (struct acpi_rsdp *) &addr[i][j]; |
||
| 75 | goto rsdp_found; |
||
| 76 | } |
||
| 77 | } |
||
| 78 | } |
||
| 79 | |||
| 80 | return; |
||
| 81 | |||
| 82 | rsdp_found: |
||
| 83 | printf("%L: ACPI Root System Description Pointer\n", acpi_rsdp); |
||
| 29 | jermar | 84 | } |