sh: kdump support.
This adds support for kexec based crash dumps.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 0b465d6..dfdfaae 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -551,6 +551,20 @@
support. As of this writing the exact hardware interface is
strongly in flux, so no good recommendation can be made.
+config CRASH_DUMP
+ bool "kernel crash dumps (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ help
+ Generate crash dump after being started by kexec.
+ This should be normally only set in special crash dump kernels
+ which are loaded in the main kernel with kexec-tools into
+ a specially reserved region and then later executed after
+ a crash by kdump/kexec. The crash dump kernel must be compiled
+ to a memory address not used by the main kernel using
+ MEMORY_START.
+
+ For more details see Documentation/kdump/kdump.txt
+
config SMP
bool "Symmetric multi-processing support"
---help---
diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile
index ff30d7f..9104b62 100644
--- a/arch/sh/kernel/Makefile
+++ b/arch/sh/kernel/Makefile
@@ -20,5 +20,6 @@
obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_PM) += pm.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
diff --git a/arch/sh/kernel/crash_dump.c b/arch/sh/kernel/crash_dump.c
new file mode 100644
index 0000000..4a2ecbe2
--- /dev/null
+++ b/arch/sh/kernel/crash_dump.c
@@ -0,0 +1,46 @@
+/*
+ * crash_dump.c - Memory preserving reboot related code.
+ *
+ * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
+ * Copyright (C) IBM Corporation, 2004. All rights reserved
+ */
+
+#include <linux/errno.h>
+#include <linux/crash_dump.h>
+#include <linux/io.h>
+#include <asm/uaccess.h>
+
+/**
+ * copy_oldmem_page - copy one page from "oldmem"
+ * @pfn: page frame number to be copied
+ * @buf: target memory address for the copy; this can be in kernel address
+ * space or user address space (see @userbuf)
+ * @csize: number of bytes to copy
+ * @offset: offset in bytes into the page (based on pfn) to begin the copy
+ * @userbuf: if set, @buf is in user address space, use copy_to_user(),
+ * otherwise @buf is in kernel address space, use memcpy().
+ *
+ * Copy a page from "oldmem". For this page, there is no pte mapped
+ * in the current kernel. We stitch up a pte, similar to kmap_atomic.
+ */
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
+ size_t csize, unsigned long offset, int userbuf)
+{
+ void *vaddr;
+
+ if (!csize)
+ return 0;
+
+ vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
+
+ if (userbuf) {
+ if (copy_to_user(buf, (vaddr + offset), csize)) {
+ iounmap(vaddr);
+ return -EFAULT;
+ }
+ } else
+ memcpy(buf, (vaddr + offset), csize);
+
+ iounmap(vaddr);
+ return csize;
+}
diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index 08587cd..790ed69 100644
--- a/arch/sh/kernel/machine_kexec.c
+++ b/arch/sh/kernel/machine_kexec.c
@@ -59,13 +59,13 @@
printk(" segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
i,
(unsigned int)image->segment[i].mem,
- (unsigned int)image->segment[i].mem + image->segment[i].memsz,
+ (unsigned int)image->segment[i].mem +
+ image->segment[i].memsz,
(unsigned int)image->segment[i].memsz);
- }
+ }
printk(" start : 0x%08x\n\n", (unsigned int)image->start);
}
-
/*
* Do not allocate memory (or fail in any way) in machine_kexec().
* We are past the point of no return, committed to rebooting now.
@@ -101,6 +101,27 @@
/* now call it */
rnk = (relocate_new_kernel_t) reboot_code_buffer;
- (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
+ (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
}
+/* crashkernel=size@addr specifies the location to reserve for
+ * a crash kernel. By reserving this memory we guarantee
+ * that linux never sets it up as a DMA target.
+ * Useful for holding code to do something appropriate
+ * after a kernel panic.
+ */
+static int __init parse_crashkernel(char *arg)
+{
+ unsigned long size, base;
+ size = memparse(arg, &arg);
+ if (*arg == '@') {
+ base = memparse(arg+1, &arg);
+ /* FIXME: Do I want a sanity check
+ * to validate the memory range?
+ */
+ crashk_res.start = base;
+ crashk_res.end = base + size - 1;
+ }
+ return 0;
+}
+early_param("crashkernel", parse_crashkernel);
diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index cab91a7..477d2a8 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -20,6 +20,7 @@
#include <linux/pfn.h>
#include <linux/fs.h>
#include <linux/mm.h>
+#include <linux/kexec.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/sections.h>
@@ -287,6 +288,11 @@
}
}
#endif
+#ifdef CONFIG_KEXEC
+ if (crashk_res.start != crashk_res.end)
+ reserve_bootmem(crashk_res.start,
+ crashk_res.end - crashk_res.start + 1);
+#endif
}
#ifndef CONFIG_NEED_MULTIPLE_NODES
diff --git a/include/asm-sh/kexec.h b/include/asm-sh/kexec.h
index 9d235af..da36a75 100644
--- a/include/asm-sh/kexec.h
+++ b/include/asm-sh/kexec.h
@@ -1,5 +1,8 @@
-#ifndef _SH_KEXEC_H
-#define _SH_KEXEC_H
+#ifndef __ASM_SH_KEXEC_H
+#define __ASM_SH_KEXEC_H
+
+#include <asm/ptrace.h>
+#include <asm/string.h>
/*
* KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
@@ -25,8 +28,37 @@
#define MAX_NOTE_BYTES 1024
-/* Provide a dummy definition to avoid build failures. */
static inline void crash_setup_regs(struct pt_regs *newregs,
- struct pt_regs *oldregs) { }
+ struct pt_regs *oldregs)
+{
+ if (oldregs)
+ memcpy(newregs, oldregs, sizeof(*newregs));
+ else {
+ __asm__ __volatile__ ("mov r0, %0" : "=r" (newregs->regs[0]));
+ __asm__ __volatile__ ("mov r1, %0" : "=r" (newregs->regs[1]));
+ __asm__ __volatile__ ("mov r2, %0" : "=r" (newregs->regs[2]));
+ __asm__ __volatile__ ("mov r3, %0" : "=r" (newregs->regs[3]));
+ __asm__ __volatile__ ("mov r4, %0" : "=r" (newregs->regs[4]));
+ __asm__ __volatile__ ("mov r5, %0" : "=r" (newregs->regs[5]));
+ __asm__ __volatile__ ("mov r6, %0" : "=r" (newregs->regs[6]));
+ __asm__ __volatile__ ("mov r7, %0" : "=r" (newregs->regs[7]));
+ __asm__ __volatile__ ("mov r8, %0" : "=r" (newregs->regs[8]));
+ __asm__ __volatile__ ("mov r9, %0" : "=r" (newregs->regs[9]));
+ __asm__ __volatile__ ("mov r10, %0" : "=r" (newregs->regs[10]));
+ __asm__ __volatile__ ("mov r11, %0" : "=r" (newregs->regs[11]));
+ __asm__ __volatile__ ("mov r12, %0" : "=r" (newregs->regs[12]));
+ __asm__ __volatile__ ("mov r13, %0" : "=r" (newregs->regs[13]));
+ __asm__ __volatile__ ("mov r14, %0" : "=r" (newregs->regs[14]));
+ __asm__ __volatile__ ("mov r15, %0" : "=r" (newregs->regs[15]));
-#endif /* _SH_KEXEC_H */
+ __asm__ __volatile__ ("sts pr, %0" : "=r" (newregs->pr));
+ __asm__ __volatile__ ("sts macl, %0" : "=r" (newregs->macl));
+ __asm__ __volatile__ ("sts mach, %0" : "=r" (newregs->mach));
+
+ __asm__ __volatile__ ("stc gbr, %0" : "=r" (newregs->gbr));
+ __asm__ __volatile__ ("stc sr, %0" : "=r" (newregs->sr));
+
+ newregs->pc = (unsigned long)current_text_addr();
+ }
+}
+#endif /* __ASM_SH_KEXEC_H */
