[POWERPC] Move some kexec logic into machine_kexec.c

We're missing a few functions for kexec to compile on 32-bit. There's
nothing really 64-bit specific about the 64-bit versions, so make them
generic rather than adding empty definitions for 32-bit.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/machine_kexec.c b/arch/powerpc/kernel/machine_kexec.c
index a81ca1b841ec..e60a0c544d63 100644
--- a/arch/powerpc/kernel/machine_kexec.c
+++ b/arch/powerpc/kernel/machine_kexec.c
@@ -13,6 +13,7 @@
 #include <linux/reboot.h>
 #include <linux/threads.h>
 #include <asm/machdep.h>
+#include <asm/lmb.h>
 
 void machine_crash_shutdown(struct pt_regs *regs)
 {
@@ -59,3 +60,58 @@ NORET_TYPE void machine_kexec(struct kimage *image)
 	}
 	for(;;);
 }
+
+static int __init early_parse_crashk(char *p)
+{
+	unsigned long size;
+
+	if (!p)
+		return 1;
+
+	size = memparse(p, &p);
+
+	if (*p == '@')
+		crashk_res.start = memparse(p + 1, &p);
+	else
+		crashk_res.start = KDUMP_KERNELBASE;
+
+	crashk_res.end = crashk_res.start + size - 1;
+
+	return 0;
+}
+early_param("crashkernel", early_parse_crashk);
+
+void __init reserve_crashkernel(void)
+{
+	unsigned long size;
+
+	if (crashk_res.start == 0)
+		return;
+
+	/* We might have got these values via the command line or the
+	 * device tree, either way sanitise them now. */
+
+	size = crashk_res.end - crashk_res.start + 1;
+
+	if (crashk_res.start != KDUMP_KERNELBASE)
+		printk("Crash kernel location must be 0x%x\n",
+				KDUMP_KERNELBASE);
+
+	crashk_res.start = KDUMP_KERNELBASE;
+	size = PAGE_ALIGN(size);
+	crashk_res.end = crashk_res.start + size - 1;
+
+	/* 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%lx\n",
+				memory_limit);
+	}
+
+	lmb_reserve(crashk_res.start, size);
+}
+
+int overlaps_crashkernel(unsigned long start, unsigned long size)
+{
+	return (start + size) > crashk_res.start && start <= crashk_res.end;
+}