54 строки
1.4 KiB
C
54 строки
1.4 KiB
C
|
/*
|
||
|
|
* Routines for doing kexec-based kdump.
|
||
|
|
*
|
||
|
|
* Copyright (C) 2005, IBM Corp.
|
||
|
|
*
|
||
|
|
* Created by: Michael Ellerman
|
||
|
|
*
|
||
|
|
* This source code is licensed under the GNU General Public License,
|
||
|
|
* Version 2. See the file COPYING for more details.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#undef DEBUG
|
||
|
|
|
||
|
|
#include <asm/kdump.h>
|
||
|
|
#include <asm/lmb.h>
|
||
|
|
#include <asm/firmware.h>
|
||
|
|
|
||
|
|
#ifdef DEBUG
|
||
|
|
#include <asm/udbg.h>
|
||
|
|
#define DBG(fmt...) udbg_printf(fmt)
|
||
|
|
#else
|
||
|
|
#define DBG(fmt...)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static void __init create_trampoline(unsigned long addr)
|
||
|
|
{
|
||
|
|
/* The maximum range of a single instruction branch, is the current
|
||
|
|
* instruction's address + (32 MB - 4) bytes. For the trampoline we
|
||
|
|
* need to branch to current address + 32 MB. So we insert a nop at
|
||
|
|
* the trampoline address, then the next instruction (+ 4 bytes)
|
||
|
|
* does a branch to (32 MB - 4). The net effect is that when we
|
||
|
|
* branch to "addr" we jump to ("addr" + 32 MB). Although it requires
|
||
|
|
* two instructions it doesn't require any registers.
|
||
|
|
*/
|
||
|
|
create_instruction(addr, 0x60000000); /* nop */
|
||
|
|
create_branch(addr + 4, addr + PHYSICAL_START, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
void __init kdump_setup(void)
|
||
|
|
{
|
||
|
|
unsigned long i;
|
||
|
|
|
||
|
|
DBG(" -> kdump_setup()\n");
|
||
|
|
|
||
|
|
for (i = KDUMP_TRAMPOLINE_START; i < KDUMP_TRAMPOLINE_END; i += 8) {
|
||
|
|
create_trampoline(i);
|
||
|
|
}
|
||
|
|
|
||
|
|
create_trampoline(__pa(system_reset_fwnmi) - PHYSICAL_START);
|
||
|
|
create_trampoline(__pa(machine_check_fwnmi) - PHYSICAL_START);
|
||
|
|
|
||
|
|
DBG(" <- kdump_setup()\n");
|
||
|
|
}
|