projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 0cc4746c ME |
1 | /* |
| 2 | * Routines for doing kexec-based kdump. | |
| 3 | * | |
| 4 | * Copyright (C) 2005, IBM Corp. | |
| 5 | * | |
| 6 | * Created by: Michael Ellerman | |
| 7 | * | |
| 8 | * This source code is licensed under the GNU General Public License, | |
| 9 | * Version 2. See the file COPYING for more details. | |
| 10 | */ | |
| 11 | ||
| 12 | #undef DEBUG | |
| 13 | ||
| cc532915 ME |
14 | #include <linux/crash_dump.h> |
| 15 | #include <linux/bootmem.h> | |
| 0cc4746c ME |
16 | #include <asm/kdump.h> |
| 17 | #include <asm/lmb.h> | |
| 18 | #include <asm/firmware.h> | |
| 19 | ||
| 20 | #ifdef DEBUG | |
| 21 | #include <asm/udbg.h> | |
| 22 | #define DBG(fmt...) udbg_printf(fmt) | |
| 23 | #else | |
| 24 | #define DBG(fmt...) | |
| 25 | #endif | |
| 26 | ||
| 27 | static void __init create_trampoline(unsigned long addr) | |
| 28 | { | |
| 29 | /* The maximum range of a single instruction branch, is the current | |
| 30 | * instruction's address + (32 MB - 4) bytes. For the trampoline we | |
| 31 | * need to branch to current address + 32 MB. So we insert a nop at | |
| 32 | * the trampoline address, then the next instruction (+ 4 bytes) | |
| 33 | * does a branch to (32 MB - 4). The net effect is that when we | |
| 34 | * branch to "addr" we jump to ("addr" + 32 MB). Although it requires | |
| 35 | * two instructions it doesn't require any registers. | |
| 36 | */ | |
| 37 | create_instruction(addr, 0x60000000); /* nop */ | |
| 38 | create_branch(addr + 4, addr + PHYSICAL_START, 0); | |
| 39 | } | |
| 40 | ||
| 41 | void __init kdump_setup(void) | |
| 42 | { | |
| 43 | unsigned long i; | |
| 44 | ||
| 45 | DBG(" -> kdump_setup()\n"); | |
| 46 | ||
| 47 | for (i = KDUMP_TRAMPOLINE_START; i < KDUMP_TRAMPOLINE_END; i += 8) { | |
| 48 | create_trampoline(i); | |
| 49 | } | |
| 50 | ||
| 51 | create_trampoline(__pa(system_reset_fwnmi) - PHYSICAL_START); | |
| 52 | create_trampoline(__pa(machine_check_fwnmi) - PHYSICAL_START); | |
| 53 | ||
| 54 | DBG(" <- kdump_setup()\n"); | |
| 55 | } | |
| cc532915 ME |
56 | |
| 57 | static int __init parse_elfcorehdr(char *p) | |
| 58 | { | |
| 59 | if (p) | |
| 60 | elfcorehdr_addr = memparse(p, &p); | |
| 61 | ||
| 62 | return 0; | |
| 63 | } | |
| 64 | __setup("elfcorehdr=", parse_elfcorehdr); | |
| 65 | ||
| 66 | static int __init parse_savemaxmem(char *p) | |
| 67 | { | |
| 68 | if (p) | |
| 69 | saved_max_pfn = (memparse(p, &p) >> PAGE_SHIFT) - 1; | |
| 70 | ||
| 71 | return 0; | |
| 72 | } | |
| 73 | __setup("savemaxmem=", parse_savemaxmem); |