/*
* Code to handle transition of Linux booting another kernel.
*
* Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
* GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
* Copyright (C) 2005 IBM Corporation.
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*/
#include <linux/kexec.h>
#include <linux/reboot.h>
#include <linux/threads.h>
#include <linux/lmb.h>
#include <linux/of.h>
#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/sections.h>
void machine_crash_shutdown(struct pt_regs *regs)
{
if (ppc_md.machine_crash_shutdown)
ppc_md.machine_crash_shutdown(regs);
else
default_machine_crash_shutdown(regs);
}
/*
* Do what every setup is needed on image and the
* reboot code buffer to allow us to avoid allocations
* later.
*/
int machine_kexec_prepare(struct kimage *image)
{
if (ppc_md.machine_kexec_prepare)
return ppc_md.machine_kexec_prepare(image);
else
return default_machine_kexec_prepare(image);
}
void machine_kexec_cleanup(struct kimage *image)
{
if (ppc_md.machine_kexec_cleanup)
ppc_md.machine_kexec_cleanup(image);
}
/*
* Do not allocate memory (or fail in any way) in machine_kexec().
* We are past the point of no return, committed to rebooting now.
*/
void machine_kexec(struct kimage *image)
{
if (ppc_md.machine_kexec)
ppc_md.machine_kexec(image);
else
default_machine_kexec(image);
/* Fall back to normal restart if we're still alive. */
machine_restart(NULL);
for(;;);
}
void __init reserve_crashkernel(void)
{
unsigned long long crash_size, crash_base;
int ret;
/* this is necessary because of lmb_phys_mem_size() */
lmb_analyze();
/* use common parsing */
ret = parse_crashkernel(boot_command_line, lmb_phys_mem_size(),
&crash_size, &crash_base);
if (ret == 0 && crash_size > 0) {
crashk_res.start = crash_base;
crashk_res.end = crash_base + crash_size - 1;
}
if (crashk_res.end == crashk_res.start) {
crashk_res.start = crashk_res.end = 0;
return;
}
/* We might have got these values via the command line or the
* device tree, either way sanitise them now. */
crash_size = crashk_res.end - crashk_res.start + 1;
#ifndef CONFIG_RELOCATABLE
if (crashk_res.start != KDUMP_KERNELBASE)
printk("Crash kernel location must be 0x%x\n",
KDUMP_KERNELBASE);
crashk_res.start = KDUMP_KERNELBASE;
#else
if (!crashk_res.start) {
/*
* unspecified address, choose a region of specified size
* can overlap with initrd (ignoring corruption when retained)
* ppc64 requires kernel and some stacks to be in first segemnt
*/
crashk_res.start = KDUMP_KERNELBASE;
}
crash_base = PAGE_ALIGN(crashk_res.start);
if (crash_base != crashk_res.start) {
printk("Crash kernel base must be aligned to 0x%lx\n",
PAGE_SIZE);
crashk_res.start = crash_base;
}
#endif
crash_size = PAGE_ALIGN(crash_size);
crashk_res.end = crashk_res.start + crash_size - 1;
/* The crash region must not overlap the current kernel */
if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
printk(KERN_WARNING
"Crash kernel can not overlap current kernel\n");
crashk_res.start = crashk_res.end = 0;
return;
}
/* Crash kernel trumps memory limit */
if (memory_limit && memory_limit <= crashk_res.end) {
memory_limit = crashk_res.end + 1;
printk("Adjusted memory limit for crashkernel, now 0x%llx\n",
(unsigned long long)memory_limit);
}
printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
"for crashkernel (System RAM: %ldMB)\n",
(unsigned long)(crash_size >> 20),
(unsigned long)(crashk_res.start >> 20),
(unsigned long)(lmb_phys_mem_size() >> 20));
lmb_reserve(crashk_res.start, crash_size);
}
int overlaps_crashkernel(unsigned long start, unsigned long size)
{
return (start + size) > crashk_res.start && start <= crashk_res.end;
}
/* Values we need to export to the second kernel via the device tree. */
static unsigned long kernel_end;
static unsigned long crashk_size;
static struct property kernel_end_prop = {
.name = "linux,kernel-end",
.length = sizeof(unsigned long),
.value = &kernel_end,
};
static struct property crashk_base_prop = {
.name = "linux,crashkernel-base",
.length = sizeof(unsigned long),
.value = &crashk_res.start,
};
static struct property crashk_size_prop = {
.name = "linux,crashkernel-size",
.length = sizeof(unsigned long),
.value = &crashk_size,
};
static void __init export_crashk_values(struct device_node *node)
{
struct property *prop;
/* There might be existing crash kernel properties, but we can't
* be sure what's in them, so remove them. */
prop = of_find_property(node, "linux,crashkernel-base", NULL);
if (prop)
prom_remove_property(node, prop);
prop = of_find_property(node, "linux,crashkernel-size", NULL);
if (prop)
prom_remove_property(node, prop);
if (crashk_res.start != 0) {
prom_add_property(node, &crashk_base_prop);
crashk_size = crashk_res.end - crashk_res.start + 1;
prom_add_property(node, &crashk_size_prop);
}
}
static int __init kexec_setup(void)
{
struct device_node *node;
struct property *prop;
node = of_find_node_by_path("/chosen");
if (!node)
return -ENOENT;
/* remove any stale properties so ours can be found */
prop = of_find_property(node, kernel_end_prop.name, NULL);
if (prop)
prom_remove_property(node, prop);
/* information needed by userspace when using default_machine_kexec */
kernel_end = __pa(_end);
prom_add_property(node, &kernel_end_prop);
export_crashk_values(node);
of_node_put(node);
return 0;
}
late_initcall(kexec_setup);
