powerpc/kexec: Move kexec files into a dedicated subdir.

arch/powerpc/kernel/ contains 8 files dedicated to kexec.

Move them into a dedicated subdirectory.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Move to a/p/kexec, drop the 'machine' naming and use 'core' instead]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/afbef97ec6a978574a5cf91a4441000e0a9da42a.1572351221.git.christophe.leroy@c-s.fr

9 files changed, 2263 insertions, 0 deletions

diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
new file mode 100644
index 000000000000..16c1c5a19519
--- /dev/null
+++ b/arch/powerpc/kexec/Makefile
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the linux kernel.
+#
+
+# Disable clang warning for using setjmp without setjmp.h header
+CFLAGS_crash.o		+= $(call cc-disable-warning, builtin-requires-header)
+
+obj-y				+= core.o crash.o core_$(BITS).o
+
+obj-$(CONFIG_PPC32)		+= relocate_32.o
+
+obj-$(CONFIG_KEXEC_FILE)	+= file_load.o elf_$(BITS).o
+
+ifdef CONFIG_HAVE_IMA_KEXEC
+ifdef CONFIG_IMA
+obj-y				+= ima.o
+endif
+endif
+
+
+# Disable GCOV, KCOV & sanitizers in odd or sensitive code
+GCOV_PROFILE_core_$(BITS).o := n
+KCOV_INSTRUMENT_core_$(BITS).o := n
+UBSAN_SANITIZE_core_$(BITS).o := n
diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
new file mode 100644
index 000000000000..078fe3d76feb
--- /dev/null
+++ b/arch/powerpc/kexec/core.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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.
+ */
+
+#include <linux/kexec.h>
+#include <linux/reboot.h>
+#include <linux/threads.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/irq.h>
+#include <linux/ftrace.h>
+
+#include <asm/kdump.h>
+#include <asm/machdep.h>
+#include <asm/pgalloc.h>
+#include <asm/prom.h>
+#include <asm/sections.h>
+
+void machine_kexec_mask_interrupts(void) {
+	unsigned int i;
+	struct irq_desc *desc;
+
+	for_each_irq_desc(i, desc) {
+		struct irq_chip *chip;
+
+		chip = irq_desc_get_chip(desc);
+		if (!chip)
+			continue;
+
+		if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
+			chip->irq_eoi(&desc->irq_data);
+
+		if (chip->irq_mask)
+			chip->irq_mask(&desc->irq_data);
+
+		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
+			chip->irq_disable(&desc->irq_data);
+	}
+}
+
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+	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)
+{
+}
+
+void arch_crash_save_vmcoreinfo(void)
+{
+
+#ifdef CONFIG_NEED_MULTIPLE_NODES
+	VMCOREINFO_SYMBOL(node_data);
+	VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
+#endif
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+	VMCOREINFO_SYMBOL(contig_page_data);
+#endif
+#if defined(CONFIG_PPC64) && defined(CONFIG_SPARSEMEM_VMEMMAP)
+	VMCOREINFO_SYMBOL(vmemmap_list);
+	VMCOREINFO_SYMBOL(mmu_vmemmap_psize);
+	VMCOREINFO_SYMBOL(mmu_psize_defs);
+	VMCOREINFO_STRUCT_SIZE(vmemmap_backing);
+	VMCOREINFO_OFFSET(vmemmap_backing, list);
+	VMCOREINFO_OFFSET(vmemmap_backing, phys);
+	VMCOREINFO_OFFSET(vmemmap_backing, virt_addr);
+	VMCOREINFO_STRUCT_SIZE(mmu_psize_def);
+	VMCOREINFO_OFFSET(mmu_psize_def, shift);
+#endif
+	vmcoreinfo_append_str("KERNELOFFSET=%lx\n", kaslr_offset());
+}
+
+/*
+ * 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)
+{
+	int save_ftrace_enabled;
+
+	save_ftrace_enabled = __ftrace_enabled_save();
+	this_cpu_disable_ftrace();
+
+	if (ppc_md.machine_kexec)
+		ppc_md.machine_kexec(image);
+	else
+		default_machine_kexec(image);
+
+	this_cpu_enable_ftrace();
+	__ftrace_enabled_restore(save_ftrace_enabled);
+
+	/* 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;
+
+	/* use common parsing */
+	ret = parse_crashkernel(boot_command_line, memblock_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 = resource_size(&crashk_res);
+
+#ifndef CONFIG_NONSTATIC_KERNEL
+	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) {
+#ifdef CONFIG_PPC64
+		/*
+		 * On 64bit we split the RMO in half but cap it at half of
+		 * a small SLB (128MB) since the crash kernel needs to place
+		 * itself and some stacks to be in the first segment.
+		 */
+		crashk_res.start = min(0x8000000ULL, (ppc64_rma_size / 2));
+#else
+		crashk_res.start = KDUMP_KERNELBASE;
+#endif
+	}
+
+	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",
+		       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)(memblock_phys_mem_size() >> 20));
+
+	if (!memblock_is_region_memory(crashk_res.start, crash_size) ||
+	    memblock_reserve(crashk_res.start, crash_size)) {
+		pr_err("Failed to reserve memory for crashkernel!\n");
+		crashk_res.start = crashk_res.end = 0;
+		return;
+	}
+}
+
+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 phys_addr_t kernel_end;
+static phys_addr_t crashk_base;
+static phys_addr_t crashk_size;
+static unsigned long long mem_limit;
+
+static struct property kernel_end_prop = {
+	.name = "linux,kernel-end",
+	.length = sizeof(phys_addr_t),
+	.value = &kernel_end,
+};
+
+static struct property crashk_base_prop = {
+	.name = "linux,crashkernel-base",
+	.length = sizeof(phys_addr_t),
+	.value = &crashk_base
+};
+
+static struct property crashk_size_prop = {
+	.name = "linux,crashkernel-size",
+	.length = sizeof(phys_addr_t),
+	.value = &crashk_size,
+};
+
+static struct property memory_limit_prop = {
+	.name = "linux,memory-limit",
+	.length = sizeof(unsigned long long),
+	.value = &mem_limit,
+};
+
+#define cpu_to_be_ulong	__PASTE(cpu_to_be, BITS_PER_LONG)
+
+static void __init export_crashk_values(struct device_node *node)
+{
+	/* There might be existing crash kernel properties, but we can't
+	 * be sure what's in them, so remove them. */
+	of_remove_property(node, of_find_property(node,
+				"linux,crashkernel-base", NULL));
+	of_remove_property(node, of_find_property(node,
+				"linux,crashkernel-size", NULL));
+
+	if (crashk_res.start != 0) {
+		crashk_base = cpu_to_be_ulong(crashk_res.start),
+		of_add_property(node, &crashk_base_prop);
+		crashk_size = cpu_to_be_ulong(resource_size(&crashk_res));
+		of_add_property(node, &crashk_size_prop);
+	}
+
+	/*
+	 * memory_limit is required by the kexec-tools to limit the
+	 * crash regions to the actual memory used.
+	 */
+	mem_limit = cpu_to_be_ulong(memory_limit);
+	of_update_property(node, &memory_limit_prop);
+}
+
+static int __init kexec_setup(void)
+{
+	struct device_node *node;
+
+	node = of_find_node_by_path("/chosen");
+	if (!node)
+		return -ENOENT;
+
+	/* remove any stale properties so ours can be found */
+	of_remove_property(node, of_find_property(node, kernel_end_prop.name, NULL));
+
+	/* information needed by userspace when using default_machine_kexec */
+	kernel_end = cpu_to_be_ulong(__pa(_end));
+	of_add_property(node, &kernel_end_prop);
+
+	export_crashk_values(node);
+
+	of_node_put(node);
+	return 0;
+}
+late_initcall(kexec_setup);
diff --git a/arch/powerpc/kexec/core_32.c b/arch/powerpc/kexec/core_32.c
new file mode 100644
index 000000000000..bf9f1f906d64
--- /dev/null
+++ b/arch/powerpc/kexec/core_32.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PPC32 code to handle 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.
+ */
+
+#include <linux/kexec.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <asm/cacheflush.h>
+#include <asm/hw_irq.h>
+#include <asm/io.h>
+
+typedef void (*relocate_new_kernel_t)(
+				unsigned long indirection_page,
+				unsigned long reboot_code_buffer,
+				unsigned long start_address) __noreturn;
+
+/*
+ * This is a generic machine_kexec function suitable at least for
+ * non-OpenFirmware embedded platforms.
+ * It merely copies the image relocation code to the control page and
+ * jumps to it.
+ * A platform specific function may just call this one.
+ */
+void default_machine_kexec(struct kimage *image)
+{
+	extern const unsigned int relocate_new_kernel_size;
+	unsigned long page_list;
+	unsigned long reboot_code_buffer, reboot_code_buffer_phys;
+	relocate_new_kernel_t rnk;
+
+	/* Interrupts aren't acceptable while we reboot */
+	local_irq_disable();
+
+	/* mask each interrupt so we are in a more sane state for the
+	 * kexec kernel */
+	machine_kexec_mask_interrupts();
+
+	page_list = image->head;
+
+	/* we need both effective and real address here */
+	reboot_code_buffer =
+			(unsigned long)page_address(image->control_code_page);
+	reboot_code_buffer_phys = virt_to_phys((void *)reboot_code_buffer);
+
+	/* copy our kernel relocation code to the control code page */
+	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
+						relocate_new_kernel_size);
+
+	flush_icache_range(reboot_code_buffer,
+				reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
+	printk(KERN_INFO "Bye!\n");
+
+	if (!IS_ENABLED(CONFIG_FSL_BOOKE) && !IS_ENABLED(CONFIG_44x))
+		relocate_new_kernel(page_list, reboot_code_buffer_phys, image->start);
+
+	/* now call it */
+	rnk = (relocate_new_kernel_t) reboot_code_buffer;
+	(*rnk)(page_list, reboot_code_buffer_phys, image->start);
+}
+
+int default_machine_kexec_prepare(struct kimage *image)
+{
+	return 0;
+}
diff --git a/arch/powerpc/kexec/core_64.c b/arch/powerpc/kexec/core_64.c
new file mode 100644
index 000000000000..04a7cba58eff
--- /dev/null
+++ b/arch/powerpc/kexec/core_64.c
@@ -0,0 +1,417 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PPC64 code to handle Linux booting another kernel.
+ *
+ * Copyright (C) 2004-2005, IBM Corp.
+ *
+ * Created by: Milton D Miller II
+ */
+
+
+#include <linux/kexec.h>
+#include <linux/smp.h>
+#include <linux/thread_info.h>
+#include <linux/init_task.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/cpu.h>
+#include <linux/hardirq.h>
+
+#include <asm/page.h>
+#include <asm/current.h>
+#include <asm/machdep.h>
+#include <asm/cacheflush.h>
+#include <asm/firmware.h>
+#include <asm/paca.h>
+#include <asm/mmu.h>
+#include <asm/sections.h>	/* _end */
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/hw_breakpoint.h>
+#include <asm/asm-prototypes.h>
+#include <asm/svm.h>
+#include <asm/ultravisor.h>
+
+int default_machine_kexec_prepare(struct kimage *image)
+{
+	int i;
+	unsigned long begin, end;	/* limits of segment */
+	unsigned long low, high;	/* limits of blocked memory range */
+	struct device_node *node;
+	const unsigned long *basep;
+	const unsigned int *sizep;
+
+	/*
+	 * Since we use the kernel fault handlers and paging code to
+	 * handle the virtual mode, we must make sure no destination
+	 * overlaps kernel static data or bss.
+	 */
+	for (i = 0; i < image->nr_segments; i++)
+		if (image->segment[i].mem < __pa(_end))
+			return -ETXTBSY;
+
+	/* We also should not overwrite the tce tables */
+	for_each_node_by_type(node, "pci") {
+		basep = of_get_property(node, "linux,tce-base", NULL);
+		sizep = of_get_property(node, "linux,tce-size", NULL);
+		if (basep == NULL || sizep == NULL)
+			continue;
+
+		low = *basep;
+		high = low + (*sizep);
+
+		for (i = 0; i < image->nr_segments; i++) {
+			begin = image->segment[i].mem;
+			end = begin + image->segment[i].memsz;
+
+			if ((begin < high) && (end > low))
+				return -ETXTBSY;
+		}
+	}
+
+	return 0;
+}
+
+static void copy_segments(unsigned long ind)
+{
+	unsigned long entry;
+	unsigned long *ptr;
+	void *dest;
+	void *addr;
+
+	/*
+	 * We rely on kexec_load to create a lists that properly
+	 * initializes these pointers before they are used.
+	 * We will still crash if the list is wrong, but at least
+	 * the compiler will be quiet.
+	 */
+	ptr = NULL;
+	dest = NULL;
+
+	for (entry = ind; !(entry & IND_DONE); entry = *ptr++) {
+		addr = __va(entry & PAGE_MASK);
+
+		switch (entry & IND_FLAGS) {
+		case IND_DESTINATION:
+			dest = addr;
+			break;
+		case IND_INDIRECTION:
+			ptr = addr;
+			break;
+		case IND_SOURCE:
+			copy_page(dest, addr);
+			dest += PAGE_SIZE;
+		}
+	}
+}
+
+void kexec_copy_flush(struct kimage *image)
+{
+	long i, nr_segments = image->nr_segments;
+	struct  kexec_segment ranges[KEXEC_SEGMENT_MAX];
+
+	/* save the ranges on the stack to efficiently flush the icache */
+	memcpy(ranges, image->segment, sizeof(ranges));
+
+	/*
+	 * After this call we may not use anything allocated in dynamic
+	 * memory, including *image.
+	 *
+	 * Only globals and the stack are allowed.
+	 */
+	copy_segments(image->head);
+
+	/*
+	 * we need to clear the icache for all dest pages sometime,
+	 * including ones that were in place on the original copy
+	 */
+	for (i = 0; i < nr_segments; i++)
+		flush_icache_range((unsigned long)__va(ranges[i].mem),
+			(unsigned long)__va(ranges[i].mem + ranges[i].memsz));
+}
+
+#ifdef CONFIG_SMP
+
+static int kexec_all_irq_disabled = 0;
+
+static void kexec_smp_down(void *arg)
+{
+	local_irq_disable();
+	hard_irq_disable();
+
+	mb(); /* make sure our irqs are disabled before we say they are */
+	get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF;
+	while(kexec_all_irq_disabled == 0)
+		cpu_relax();
+	mb(); /* make sure all irqs are disabled before this */
+	hw_breakpoint_disable();
+	/*
+	 * Now every CPU has IRQs off, we can clear out any pending
+	 * IPIs and be sure that no more will come in after this.
+	 */
+	if (ppc_md.kexec_cpu_down)
+		ppc_md.kexec_cpu_down(0, 1);
+
+	kexec_smp_wait();
+	/* NOTREACHED */
+}
+
+static void kexec_prepare_cpus_wait(int wait_state)
+{
+	int my_cpu, i, notified=-1;
+
+	hw_breakpoint_disable();
+	my_cpu = get_cpu();
+	/* Make sure each CPU has at least made it to the state we need.
+	 *
+	 * FIXME: There is a (slim) chance of a problem if not all of the CPUs
+	 * are correctly onlined.  If somehow we start a CPU on boot with RTAS
+	 * start-cpu, but somehow that CPU doesn't write callin_cpu_map[] in
+	 * time, the boot CPU will timeout.  If it does eventually execute
+	 * stuff, the secondary will start up (paca_ptrs[]->cpu_start was
+	 * written) and get into a peculiar state.
+	 * If the platform supports smp_ops->take_timebase(), the secondary CPU
+	 * will probably be spinning in there.  If not (i.e. pseries), the
+	 * secondary will continue on and try to online itself/idle/etc. If it
+	 * survives that, we need to find these
+	 * possible-but-not-online-but-should-be CPUs and chaperone them into
+	 * kexec_smp_wait().
+	 */
+	for_each_online_cpu(i) {
+		if (i == my_cpu)
+			continue;
+
+		while (paca_ptrs[i]->kexec_state < wait_state) {
+			barrier();
+			if (i != notified) {
+				printk(KERN_INFO "kexec: waiting for cpu %d "
+				       "(physical %d) to enter %i state\n",
+				       i, paca_ptrs[i]->hw_cpu_id, wait_state);
+				notified = i;
+			}
+		}
+	}
+	mb();
+}
+
+/*
+ * We need to make sure each present CPU is online.  The next kernel will scan
+ * the device tree and assume primary threads are online and query secondary
+ * threads via RTAS to online them if required.  If we don't online primary
+ * threads, they will be stuck.  However, we also online secondary threads as we
+ * may be using 'cede offline'.  In this case RTAS doesn't see the secondary
+ * threads as offline -- and again, these CPUs will be stuck.
+ *
+ * So, we online all CPUs that should be running, including secondary threads.
+ */
+static void wake_offline_cpus(void)
+{
+	int cpu = 0;
+
+	for_each_present_cpu(cpu) {
+		if (!cpu_online(cpu)) {
+			printk(KERN_INFO "kexec: Waking offline cpu %d.\n",
+			       cpu);
+			WARN_ON(cpu_up(cpu));
+		}
+	}
+}
+
+static void kexec_prepare_cpus(void)
+{
+	wake_offline_cpus();
+	smp_call_function(kexec_smp_down, NULL, /* wait */0);
+	local_irq_disable();
+	hard_irq_disable();
+
+	mb(); /* make sure IRQs are disabled before we say they are */
+	get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF;
+
+	kexec_prepare_cpus_wait(KEXEC_STATE_IRQS_OFF);
+	/* we are sure every CPU has IRQs off at this point */
+	kexec_all_irq_disabled = 1;
+
+	/*
+	 * Before removing MMU mappings make sure all CPUs have entered real
+	 * mode:
+	 */
+	kexec_prepare_cpus_wait(KEXEC_STATE_REAL_MODE);
+
+	/* after we tell the others to go down */
+	if (ppc_md.kexec_cpu_down)
+		ppc_md.kexec_cpu_down(0, 0);
+
+	put_cpu();
+}
+
+#else /* ! SMP */
+
+static void kexec_prepare_cpus(void)
+{
+	/*
+	 * move the secondarys to us so that we can copy
+	 * the new kernel 0-0x100 safely
+	 *
+	 * do this if kexec in setup.c ?
+	 *
+	 * We need to release the cpus if we are ever going from an
+	 * UP to an SMP kernel.
+	 */
+	smp_release_cpus();
+	if (ppc_md.kexec_cpu_down)
+		ppc_md.kexec_cpu_down(0, 0);
+	local_irq_disable();
+	hard_irq_disable();
+}
+
+#endif /* SMP */
+
+/*
+ * kexec thread structure and stack.
+ *
+ * We need to make sure that this is 16384-byte aligned due to the
+ * way process stacks are handled.  It also must be statically allocated
+ * or allocated as part of the kimage, because everything else may be
+ * overwritten when we copy the kexec image.  We piggyback on the
+ * "init_task" linker section here to statically allocate a stack.
+ *
+ * We could use a smaller stack if we don't care about anything using
+ * current, but that audit has not been performed.
+ */
+static union thread_union kexec_stack __init_task_data =
+	{ };
+
+/*
+ * For similar reasons to the stack above, the kexecing CPU needs to be on a
+ * static PACA; we switch to kexec_paca.
+ */
+struct paca_struct kexec_paca;
+
+/* Our assembly helper, in misc_64.S */
+extern void kexec_sequence(void *newstack, unsigned long start,
+			   void *image, void *control,
+			   void (*clear_all)(void),
+			   bool copy_with_mmu_off) __noreturn;
+
+/* too late to fail here */
+void default_machine_kexec(struct kimage *image)
+{
+	bool copy_with_mmu_off;
+
+	/* prepare control code if any */
+
+	/*
+        * If the kexec boot is the normal one, need to shutdown other cpus
+        * into our wait loop and quiesce interrupts.
+        * Otherwise, in the case of crashed mode (crashing_cpu >= 0),
+        * stopping other CPUs and collecting their pt_regs is done before
+        * using debugger IPI.
+        */
+
+	if (!kdump_in_progress())
+		kexec_prepare_cpus();
+
+	printk("kexec: Starting switchover sequence.\n");
+
+	/* switch to a staticly allocated stack.  Based on irq stack code.
+	 * We setup preempt_count to avoid using VMX in memcpy.
+	 * XXX: the task struct will likely be invalid once we do the copy!
+	 */
+	current_thread_info()->flags = 0;
+	current_thread_info()->preempt_count = HARDIRQ_OFFSET;
+
+	/* We need a static PACA, too; copy this CPU's PACA over and switch to
+	 * it. Also poison per_cpu_offset and NULL lppaca to catch anyone using
+	 * non-static data.
+	 */
+	memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct));
+	kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL;
+#ifdef CONFIG_PPC_PSERIES
+	kexec_paca.lppaca_ptr = NULL;
+#endif
+
+	if (is_secure_guest() && !(image->preserve_context ||
+				   image->type == KEXEC_TYPE_CRASH)) {
+		uv_unshare_all_pages();
+		printk("kexec: Unshared all shared pages.\n");
+	}
+
+	paca_ptrs[kexec_paca.paca_index] = &kexec_paca;
+
+	setup_paca(&kexec_paca);
+
+	/*
+	 * The lppaca should be unregistered at this point so the HV won't
+	 * touch it. In the case of a crash, none of the lppacas are
+	 * unregistered so there is not much we can do about it here.
+	 */
+
+	/*
+	 * On Book3S, the copy must happen with the MMU off if we are either
+	 * using Radix page tables or we are not in an LPAR since we can
+	 * overwrite the page tables while copying.
+	 *
+	 * In an LPAR, we keep the MMU on otherwise we can't access beyond
+	 * the RMA. On BookE there is no real MMU off mode, so we have to
+	 * keep it enabled as well (but then we have bolted TLB entries).
+	 */
+#ifdef CONFIG_PPC_BOOK3E
+	copy_with_mmu_off = false;
+#else
+	copy_with_mmu_off = radix_enabled() ||
+		!(firmware_has_feature(FW_FEATURE_LPAR) ||
+		  firmware_has_feature(FW_FEATURE_PS3_LV1));
+#endif
+
+	/* Some things are best done in assembly.  Finding globals with
+	 * a toc is easier in C, so pass in what we can.
+	 */
+	kexec_sequence(&kexec_stack, image->start, image,
+		       page_address(image->control_code_page),
+		       mmu_cleanup_all, copy_with_mmu_off);
+	/* NOTREACHED */
+}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+/* Values we need to export to the second kernel via the device tree. */
+static unsigned long htab_base;
+static unsigned long htab_size;
+
+static struct property htab_base_prop = {
+	.name = "linux,htab-base",
+	.length = sizeof(unsigned long),
+	.value = &htab_base,
+};
+
+static struct property htab_size_prop = {
+	.name = "linux,htab-size",
+	.length = sizeof(unsigned long),
+	.value = &htab_size,
+};
+
+static int __init export_htab_values(void)
+{
+	struct device_node *node;
+
+	/* On machines with no htab htab_address is NULL */
+	if (!htab_address)
+		return -ENODEV;
+
+	node = of_find_node_by_path("/chosen");
+	if (!node)
+		return -ENODEV;
+
+	/* remove any stale propertys so ours can be found */
+	of_remove_property(node, of_find_property(node, htab_base_prop.name, NULL));
+	of_remove_property(node, of_find_property(node, htab_size_prop.name, NULL));
+
+	htab_base = cpu_to_be64(__pa(htab_address));
+	of_add_property(node, &htab_base_prop);
+	htab_size = cpu_to_be64(htab_size_bytes);
+	of_add_property(node, &htab_size_prop);
+
+	of_node_put(node);
+	return 0;
+}
+late_initcall(export_htab_values);
+#endif /* CONFIG_PPC_BOOK3S_64 */
diff --git a/arch/powerpc/kexec/crash.c b/arch/powerpc/kexec/crash.c
new file mode 100644
index 000000000000..d488311efab1
--- /dev/null
+++ b/arch/powerpc/kexec/crash.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Architecture specific (PPC64) functions for kexec based crash dumps.
+ *
+ * Copyright (C) 2005, IBM Corp.
+ *
+ * Created by: Haren Myneni
+ */
+
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/reboot.h>
+#include <linux/kexec.h>
+#include <linux/export.h>
+#include <linux/crash_dump.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/types.h>
+
+#include <asm/processor.h>
+#include <asm/machdep.h>
+#include <asm/kexec.h>
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/setjmp.h>
+#include <asm/debug.h>
+
+/*
+ * The primary CPU waits a while for all secondary CPUs to enter. This is to
+ * avoid sending an IPI if the secondary CPUs are entering
+ * crash_kexec_secondary on their own (eg via a system reset).
+ *
+ * The secondary timeout has to be longer than the primary. Both timeouts are
+ * in milliseconds.
+ */
+#define PRIMARY_TIMEOUT		500
+#define SECONDARY_TIMEOUT	1000
+
+#define IPI_TIMEOUT		10000
+#define REAL_MODE_TIMEOUT	10000
+
+static int time_to_dump;
+/*
+ * crash_wake_offline should be set to 1 by platforms that intend to wake
+ * up offline cpus prior to jumping to a kdump kernel. Currently powernv
+ * sets it to 1, since we want to avoid things from happening when an
+ * offline CPU wakes up due to something like an HMI (malfunction error),
+ * which propagates to all threads.
+ */
+int crash_wake_offline;
+
+#define CRASH_HANDLER_MAX 3
+/* List of shutdown handles */
+static crash_shutdown_t crash_shutdown_handles[CRASH_HANDLER_MAX];
+static DEFINE_SPINLOCK(crash_handlers_lock);
+
+static unsigned long crash_shutdown_buf[JMP_BUF_LEN];
+static int crash_shutdown_cpu = -1;
+
+static int handle_fault(struct pt_regs *regs)
+{
+	if (crash_shutdown_cpu == smp_processor_id())
+		longjmp(crash_shutdown_buf, 1);
+	return 0;
+}
+
+#ifdef CONFIG_SMP
+
+static atomic_t cpus_in_crash;
+void crash_ipi_callback(struct pt_regs *regs)
+{
+	static cpumask_t cpus_state_saved = CPU_MASK_NONE;
+
+	int cpu = smp_processor_id();
+
+	hard_irq_disable();
+	if (!cpumask_test_cpu(cpu, &cpus_state_saved)) {
+		crash_save_cpu(regs, cpu);
+		cpumask_set_cpu(cpu, &cpus_state_saved);
+	}
+
+	atomic_inc(&cpus_in_crash);
+	smp_mb__after_atomic();
+
+	/*
+	 * Starting the kdump boot.
+	 * This barrier is needed to make sure that all CPUs are stopped.
+	 */
+	while (!time_to_dump)
+		cpu_relax();
+
+	if (ppc_md.kexec_cpu_down)
+		ppc_md.kexec_cpu_down(1, 1);
+
+#ifdef CONFIG_PPC64
+	kexec_smp_wait();
+#else
+	for (;;);	/* FIXME */
+#endif
+
+	/* NOTREACHED */
+}
+
+static void crash_kexec_prepare_cpus(int cpu)
+{
+	unsigned int msecs;
+	unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */
+	int tries = 0;
+	int (*old_handler)(struct pt_regs *regs);
+
+	printk(KERN_EMERG "Sending IPI to other CPUs\n");
+
+	if (crash_wake_offline)
+		ncpus = num_present_cpus() - 1;
+
+	crash_send_ipi(crash_ipi_callback);
+	smp_wmb();
+
+again:
+	/*
+	 * FIXME: Until we will have the way to stop other CPUs reliably,
+	 * the crash CPU will send an IPI and wait for other CPUs to
+	 * respond.
+	 */
+	msecs = IPI_TIMEOUT;
+	while ((atomic_read(&cpus_in_crash) < ncpus) && (--msecs > 0))
+		mdelay(1);
+
+	/* Would it be better to replace the trap vector here? */
+
+	if (atomic_read(&cpus_in_crash) >= ncpus) {
+		printk(KERN_EMERG "IPI complete\n");
+		return;
+	}
+
+	printk(KERN_EMERG "ERROR: %d cpu(s) not responding\n",
+		ncpus - atomic_read(&cpus_in_crash));
+
+	/*
+	 * If we have a panic timeout set then we can't wait indefinitely
+	 * for someone to activate system reset. We also give up on the
+	 * second time through if system reset fail to work.
+	 */
+	if ((panic_timeout > 0) || (tries > 0))
+		return;
+
+	/*
+	 * A system reset will cause all CPUs to take an 0x100 exception.
+	 * The primary CPU returns here via setjmp, and the secondary
+	 * CPUs reexecute the crash_kexec_secondary path.
+	 */
+	old_handler = __debugger;
+	__debugger = handle_fault;
+	crash_shutdown_cpu = smp_processor_id();
+
+	if (setjmp(crash_shutdown_buf) == 0) {
+		printk(KERN_EMERG "Activate system reset (dumprestart) "
+				  "to stop other cpu(s)\n");
+
+		/*
+		 * A system reset will force all CPUs to execute the
+		 * crash code again. We need to reset cpus_in_crash so we
+		 * wait for everyone to do this.
+		 */
+		atomic_set(&cpus_in_crash, 0);
+		smp_mb();
+
+		while (atomic_read(&cpus_in_crash) < ncpus)
+			cpu_relax();
+	}
+
+	crash_shutdown_cpu = -1;
+	__debugger = old_handler;
+
+	tries++;
+	goto again;
+}
+
+/*
+ * This function will be called by secondary cpus.
+ */
+void crash_kexec_secondary(struct pt_regs *regs)
+{
+	unsigned long flags;
+	int msecs = SECONDARY_TIMEOUT;
+
+	local_irq_save(flags);
+
+	/* Wait for the primary crash CPU to signal its progress */
+	while (crashing_cpu < 0) {
+		if (--msecs < 0) {
+			/* No response, kdump image may not have been loaded */
+			local_irq_restore(flags);
+			return;
+		}
+
+		mdelay(1);
+	}
+
+	crash_ipi_callback(regs);
+}
+
+#else	/* ! CONFIG_SMP */
+
+static void crash_kexec_prepare_cpus(int cpu)
+{
+	/*
+	 * move the secondaries to us so that we can copy
+	 * the new kernel 0-0x100 safely
+	 *
+	 * do this if kexec in setup.c ?
+	 */
+#ifdef CONFIG_PPC64
+	smp_release_cpus();
+#else
+	/* FIXME */
+#endif
+}
+
+void crash_kexec_secondary(struct pt_regs *regs)
+{
+}
+#endif	/* CONFIG_SMP */
+
+/* wait for all the CPUs to hit real mode but timeout if they don't come in */
+#if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
+static void __maybe_unused crash_kexec_wait_realmode(int cpu)
+{
+	unsigned int msecs;
+	int i;
+
+	msecs = REAL_MODE_TIMEOUT;
+	for (i=0; i < nr_cpu_ids && msecs > 0; i++) {
+		if (i == cpu)
+			continue;
+
+		while (paca_ptrs[i]->kexec_state < KEXEC_STATE_REAL_MODE) {
+			barrier();
+			if (!cpu_possible(i) || !cpu_online(i) || (msecs <= 0))
+				break;
+			msecs--;
+			mdelay(1);
+		}
+	}
+	mb();
+}
+#else
+static inline void crash_kexec_wait_realmode(int cpu) {}
+#endif	/* CONFIG_SMP && CONFIG_PPC64 */
+
+/*
+ * Register a function to be called on shutdown.  Only use this if you
+ * can't reset your device in the second kernel.
+ */
+int crash_shutdown_register(crash_shutdown_t handler)
+{
+	unsigned int i, rc;
+
+	spin_lock(&crash_handlers_lock);
+	for (i = 0 ; i < CRASH_HANDLER_MAX; i++)
+		if (!crash_shutdown_handles[i]) {
+			/* Insert handle at first empty entry */
+			crash_shutdown_handles[i] = handler;
+			rc = 0;
+			break;
+		}
+
+	if (i == CRASH_HANDLER_MAX) {
+		printk(KERN_ERR "Crash shutdown handles full, "
+		       "not registered.\n");
+		rc = 1;
+	}
+
+	spin_unlock(&crash_handlers_lock);
+	return rc;
+}
+EXPORT_SYMBOL(crash_shutdown_register);
+
+int crash_shutdown_unregister(crash_shutdown_t handler)
+{
+	unsigned int i, rc;
+
+	spin_lock(&crash_handlers_lock);
+	for (i = 0 ; i < CRASH_HANDLER_MAX; i++)
+		if (crash_shutdown_handles[i] == handler)
+			break;
+
+	if (i == CRASH_HANDLER_MAX) {
+		printk(KERN_ERR "Crash shutdown handle not found\n");
+		rc = 1;
+	} else {
+		/* Shift handles down */
+		for (; i < (CRASH_HANDLER_MAX - 1); i++)
+			crash_shutdown_handles[i] =
+				crash_shutdown_handles[i+1];
+		/*
+		 * Reset last entry to NULL now that it has been shifted down,
+		 * this will allow new handles to be added here.
+		 */
+		crash_shutdown_handles[i] = NULL;
+		rc = 0;
+	}
+
+	spin_unlock(&crash_handlers_lock);
+	return rc;
+}
+EXPORT_SYMBOL(crash_shutdown_unregister);
+
+void default_machine_crash_shutdown(struct pt_regs *regs)
+{
+	unsigned int i;
+	int (*old_handler)(struct pt_regs *regs);
+
+	/*
+	 * This function is only called after the system
+	 * has panicked or is otherwise in a critical state.
+	 * The minimum amount of code to allow a kexec'd kernel
+	 * to run successfully needs to happen here.
+	 *
+	 * In practice this means stopping other cpus in
+	 * an SMP system.
+	 * The kernel is broken so disable interrupts.
+	 */
+	hard_irq_disable();
+
+	/*
+	 * Make a note of crashing cpu. Will be used in machine_kexec
+	 * such that another IPI will not be sent.
+	 */
+	crashing_cpu = smp_processor_id();
+
+	/*
+	 * If we came in via system reset, wait a while for the secondary
+	 * CPUs to enter.
+	 */
+	if (TRAP(regs) == 0x100)
+		mdelay(PRIMARY_TIMEOUT);
+
+	crash_kexec_prepare_cpus(crashing_cpu);
+
+	crash_save_cpu(regs, crashing_cpu);
+
+	time_to_dump = 1;
+
+	crash_kexec_wait_realmode(crashing_cpu);
+
+	machine_kexec_mask_interrupts();
+
+	/*
+	 * Call registered shutdown routines safely.  Swap out
+	 * __debugger_fault_handler, and replace on exit.
+	 */
+	old_handler = __debugger_fault_handler;
+	__debugger_fault_handler = handle_fault;
+	crash_shutdown_cpu = smp_processor_id();
+	for (i = 0; i < CRASH_HANDLER_MAX && crash_shutdown_handles[i]; i++) {
+		if (setjmp(crash_shutdown_buf) == 0) {
+			/*
+			 * Insert syncs and delay to ensure
+			 * instructions in the dangerous region don't
+			 * leak away from this protected region.
+			 */
+			asm volatile("sync; isync");
+			/* dangerous region */
+			crash_shutdown_handles[i]();
+			asm volatile("sync; isync");
+		}
+	}
+	crash_shutdown_cpu = -1;
+	__debugger_fault_handler = old_handler;
+
+	if (ppc_md.kexec_cpu_down)
+		ppc_md.kexec_cpu_down(1, 0);
+}
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
new file mode 100644
index 000000000000..3072fd6dbe94
--- /dev/null
+++ b/arch/powerpc/kexec/elf_64.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Load ELF vmlinux file for the kexec_file_load syscall.
+ *
+ * Copyright (C) 2004  Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004  IBM Corp.
+ * Copyright (C) 2005  R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006  Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2016  IBM Corporation
+ *
+ * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c.
+ * Heavily modified for the kernel by
+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
+ */
+
+#define pr_fmt(fmt)	"kexec_elf: " fmt
+
+#include <linux/elf.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/module.h>
+#include <linux/of_fdt.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+static void *elf64_load(struct kimage *image, char *kernel_buf,
+			unsigned long kernel_len, char *initrd,
+			unsigned long initrd_len, char *cmdline,
+			unsigned long cmdline_len)
+{
+	int ret;
+	unsigned int fdt_size;
+	unsigned long kernel_load_addr;
+	unsigned long initrd_load_addr = 0, fdt_load_addr;
+	void *fdt;
+	const void *slave_code;
+	struct elfhdr ehdr;
+	struct kexec_elf_info elf_info;
+	struct kexec_buf kbuf = { .image = image, .buf_min = 0,
+				  .buf_max = ppc64_rma_size };
+	struct kexec_buf pbuf = { .image = image, .buf_min = 0,
+				  .buf_max = ppc64_rma_size, .top_down = true,
+				  .mem = KEXEC_BUF_MEM_UNKNOWN };
+
+	ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info);
+	if (ret)
+		goto out;
+
+	ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr);
+	if (ret)
+		goto out;
+
+	pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
+
+	ret = kexec_load_purgatory(image, &pbuf);
+	if (ret) {
+		pr_err("Loading purgatory failed.\n");
+		goto out;
+	}
+
+	pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem);
+
+	if (initrd != NULL) {
+		kbuf.buffer = initrd;
+		kbuf.bufsz = kbuf.memsz = initrd_len;
+		kbuf.buf_align = PAGE_SIZE;
+		kbuf.top_down = false;
+		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+		ret = kexec_add_buffer(&kbuf);
+		if (ret)
+			goto out;
+		initrd_load_addr = kbuf.mem;
+
+		pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
+	}
+
+	fdt_size = fdt_totalsize(initial_boot_params) * 2;
+	fdt = kmalloc(fdt_size, GFP_KERNEL);
+	if (!fdt) {
+		pr_err("Not enough memory for the device tree.\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+	ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
+	if (ret < 0) {
+		pr_err("Error setting up the new device tree.\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+	if (ret)
+		goto out;
+
+	fdt_pack(fdt);
+
+	kbuf.buffer = fdt;
+	kbuf.bufsz = kbuf.memsz = fdt_size;
+	kbuf.buf_align = PAGE_SIZE;
+	kbuf.top_down = true;
+	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+	ret = kexec_add_buffer(&kbuf);
+	if (ret)
+		goto out;
+	fdt_load_addr = kbuf.mem;
+
+	pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
+
+	slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
+	ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
+			      fdt_load_addr);
+	if (ret)
+		pr_err("Error setting up the purgatory.\n");
+
+out:
+	kexec_free_elf_info(&elf_info);
+
+	/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
+	return ret ? ERR_PTR(ret) : fdt;
+}
+
+const struct kexec_file_ops kexec_elf64_ops = {
+	.probe = kexec_elf_probe,
+	.load = elf64_load,
+};
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
new file mode 100644
index 000000000000..143c91724617
--- /dev/null
+++ b/arch/powerpc/kexec/file_load.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ppc64 code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004  Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004  IBM Corp.
+ * Copyright (C) 2004,2005  Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005  R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006  Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2016  IBM Corporation
+ *
+ * Based on kexec-tools' kexec-elf-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
+ */
+
+#include <linux/slab.h>
+#include <linux/kexec.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+#include <asm/ima.h>
+
+#define SLAVE_CODE_SIZE		256
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+	&kexec_elf64_ops,
+	NULL
+};
+
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+				  unsigned long buf_len)
+{
+	/* We don't support crash kernels yet. */
+	if (image->type == KEXEC_TYPE_CRASH)
+		return -EOPNOTSUPP;
+
+	return kexec_image_probe_default(image, buf, buf_len);
+}
+
+/**
+ * setup_purgatory - initialize the purgatory's global variables
+ * @image:		kexec image.
+ * @slave_code:		Slave code for the purgatory.
+ * @fdt:		Flattened device tree for the next kernel.
+ * @kernel_load_addr:	Address where the kernel is loaded.
+ * @fdt_load_addr:	Address where the flattened device tree is loaded.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_purgatory(struct kimage *image, const void *slave_code,
+		    const void *fdt, unsigned long kernel_load_addr,
+		    unsigned long fdt_load_addr)
+{
+	unsigned int *slave_code_buf, master_entry;
+	int ret;
+
+	slave_code_buf = kmalloc(SLAVE_CODE_SIZE, GFP_KERNEL);
+	if (!slave_code_buf)
+		return -ENOMEM;
+
+	/* Get the slave code from the new kernel and put it in purgatory. */
+	ret = kexec_purgatory_get_set_symbol(image, "purgatory_start",
+					     slave_code_buf, SLAVE_CODE_SIZE,
+					     true);
+	if (ret) {
+		kfree(slave_code_buf);
+		return ret;
+	}
+
+	master_entry = slave_code_buf[0];
+	memcpy(slave_code_buf, slave_code, SLAVE_CODE_SIZE);
+	slave_code_buf[0] = master_entry;
+	ret = kexec_purgatory_get_set_symbol(image, "purgatory_start",
+					     slave_code_buf, SLAVE_CODE_SIZE,
+					     false);
+	kfree(slave_code_buf);
+
+	ret = kexec_purgatory_get_set_symbol(image, "kernel", &kernel_load_addr,
+					     sizeof(kernel_load_addr), false);
+	if (ret)
+		return ret;
+	ret = kexec_purgatory_get_set_symbol(image, "dt_offset", &fdt_load_addr,
+					     sizeof(fdt_load_addr), false);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/**
+ * delete_fdt_mem_rsv - delete memory reservation with given address and size
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
+{
+	int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
+
+	for (i = 0; i < num_rsvs; i++) {
+		uint64_t rsv_start, rsv_size;
+
+		ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
+		if (ret) {
+			pr_err("Malformed device tree.\n");
+			return -EINVAL;
+		}
+
+		if (rsv_start == start && rsv_size == size) {
+			ret = fdt_del_mem_rsv(fdt, i);
+			if (ret) {
+				pr_err("Error deleting device tree reservation.\n");
+				return -EINVAL;
+			}
+
+			return 0;
+		}
+	}
+
+	return -ENOENT;
+}
+
+/*
+ * setup_new_fdt - modify /chosen and memory reservation for the next kernel
+ * @image:		kexec image being loaded.
+ * @fdt:		Flattened device tree for the next kernel.
+ * @initrd_load_addr:	Address where the next initrd will be loaded.
+ * @initrd_len:		Size of the next initrd, or 0 if there will be none.
+ * @cmdline:		Command line for the next kernel, or NULL if there will
+ *			be none.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_new_fdt(const struct kimage *image, void *fdt,
+		  unsigned long initrd_load_addr, unsigned long initrd_len,
+		  const char *cmdline)
+{
+	int ret, chosen_node;
+	const void *prop;
+
+	/* Remove memory reservation for the current device tree. */
+	ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
+				 fdt_totalsize(initial_boot_params));
+	if (ret == 0)
+		pr_debug("Removed old device tree reservation.\n");
+	else if (ret != -ENOENT)
+		return ret;
+
+	chosen_node = fdt_path_offset(fdt, "/chosen");
+	if (chosen_node == -FDT_ERR_NOTFOUND) {
+		chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
+					      "chosen");
+		if (chosen_node < 0) {
+			pr_err("Error creating /chosen.\n");
+			return -EINVAL;
+		}
+	} else if (chosen_node < 0) {
+		pr_err("Malformed device tree: error reading /chosen.\n");
+		return -EINVAL;
+	}
+
+	/* Did we boot using an initrd? */
+	prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
+	if (prop) {
+		uint64_t tmp_start, tmp_end, tmp_size;
+
+		tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+		prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
+		if (!prop) {
+			pr_err("Malformed device tree.\n");
+			return -EINVAL;
+		}
+		tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+		/*
+		 * kexec reserves exact initrd size, while firmware may
+		 * reserve a multiple of PAGE_SIZE, so check for both.
+		 */
+		tmp_size = tmp_end - tmp_start;
+		ret = delete_fdt_mem_rsv(fdt, tmp_start, tmp_size);
+		if (ret == -ENOENT)
+			ret = delete_fdt_mem_rsv(fdt, tmp_start,
+						 round_up(tmp_size, PAGE_SIZE));
+		if (ret == 0)
+			pr_debug("Removed old initrd reservation.\n");
+		else if (ret != -ENOENT)
+			return ret;
+
+		/* If there's no new initrd, delete the old initrd's info. */
+		if (initrd_len == 0) {
+			ret = fdt_delprop(fdt, chosen_node,
+					  "linux,initrd-start");
+			if (ret) {
+				pr_err("Error deleting linux,initrd-start.\n");
+				return -EINVAL;
+			}
+
+			ret = fdt_delprop(fdt, chosen_node, "linux,initrd-end");
+			if (ret) {
+				pr_err("Error deleting linux,initrd-end.\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	if (initrd_len) {
+		ret = fdt_setprop_u64(fdt, chosen_node,
+				      "linux,initrd-start",
+				      initrd_load_addr);
+		if (ret < 0)
+			goto err;
+
+		/* initrd-end is the first address after the initrd image. */
+		ret = fdt_setprop_u64(fdt, chosen_node, "linux,initrd-end",
+				      initrd_load_addr + initrd_len);
+		if (ret < 0)
+			goto err;
+
+		ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
+		if (ret) {
+			pr_err("Error reserving initrd memory: %s\n",
+			       fdt_strerror(ret));
+			return -EINVAL;
+		}
+	}
+
+	if (cmdline != NULL) {
+		ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
+		if (ret < 0)
+			goto err;
+	} else {
+		ret = fdt_delprop(fdt, chosen_node, "bootargs");
+		if (ret && ret != -FDT_ERR_NOTFOUND) {
+			pr_err("Error deleting bootargs.\n");
+			return -EINVAL;
+		}
+	}
+
+	ret = setup_ima_buffer(image, fdt, chosen_node);
+	if (ret) {
+		pr_err("Error setting up the new device tree.\n");
+		return ret;
+	}
+
+	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	if (ret)
+		goto err;
+
+	return 0;
+
+err:
+	pr_err("Error setting up the new device tree.\n");
+	return -EINVAL;
+}
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
new file mode 100644
index 000000000000..720e50e490b6
--- /dev/null
+++ b/arch/powerpc/kexec/ima.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 IBM Corporation
+ *
+ * Authors:
+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
+ */
+
+#include <linux/slab.h>
+#include <linux/kexec.h>
+#include <linux/of.h>
+#include <linux/memblock.h>
+#include <linux/libfdt.h>
+
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	*addr_cells = of_n_addr_cells(root);
+	*size_cells = of_n_size_cells(root);
+
+	of_node_put(root);
+
+	return 0;
+}
+
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+			       size_t *size)
+{
+	int ret, addr_cells, size_cells;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	if (len < 4 * (addr_cells + size_cells))
+		return -ENOENT;
+
+	*addr = of_read_number(prop, addr_cells);
+	*size = of_read_number(prop + 4 * addr_cells, size_cells);
+
+	return 0;
+}
+
+/**
+ * ima_get_kexec_buffer - get IMA buffer from the previous kernel
+ * @addr:	On successful return, set to point to the buffer contents.
+ * @size:	On successful return, set to the buffer size.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int ima_get_kexec_buffer(void **addr, size_t *size)
+{
+	int ret, len;
+	unsigned long tmp_addr;
+	size_t tmp_size;
+	const void *prop;
+
+	prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return -ENOENT;
+
+	ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
+	if (ret)
+		return ret;
+
+	*addr = __va(tmp_addr);
+	*size = tmp_size;
+
+	return 0;
+}
+
+/**
+ * ima_free_kexec_buffer - free memory used by the IMA buffer
+ */
+int ima_free_kexec_buffer(void)
+{
+	int ret;
+	unsigned long addr;
+	size_t size;
+	struct property *prop;
+
+	prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
+	if (!prop)
+		return -ENOENT;
+
+	ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
+	if (ret)
+		return ret;
+
+	ret = of_remove_property(of_chosen, prop);
+	if (ret)
+		return ret;
+
+	return memblock_free(addr, size);
+
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+void remove_ima_buffer(void *fdt, int chosen_node)
+{
+	int ret, len;
+	unsigned long addr;
+	size_t size;
+	const void *prop;
+
+	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return;
+
+	ret = do_get_kexec_buffer(prop, len, &addr, &size);
+	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+	if (ret)
+		return;
+
+	ret = delete_fdt_mem_rsv(fdt, addr, size);
+	if (!ret)
+		pr_debug("Removed old IMA buffer reservation.\n");
+}
+
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer
+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+			      size_t size)
+{
+	image->arch.ima_buffer_addr = load_addr;
+	image->arch.ima_buffer_size = size;
+
+	return 0;
+}
+
+static int write_number(void *p, u64 value, int cells)
+{
+	if (cells == 1) {
+		u32 tmp;
+
+		if (value > U32_MAX)
+			return -EINVAL;
+
+		tmp = cpu_to_be32(value);
+		memcpy(p, &tmp, sizeof(tmp));
+	} else if (cells == 2) {
+		u64 tmp;
+
+		tmp = cpu_to_be64(value);
+		memcpy(p, &tmp, sizeof(tmp));
+	} else
+		return -EINVAL;
+
+	return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image:		kexec image being loaded.
+ * @fdt:		Flattened device tree for the next kernel.
+ * @chosen_node:	Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
+{
+	int ret, addr_cells, size_cells, entry_size;
+	u8 value[16];
+
+	remove_ima_buffer(fdt, chosen_node);
+	if (!image->arch.ima_buffer_size)
+		return 0;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	entry_size = 4 * (addr_cells + size_cells);
+
+	if (entry_size > sizeof(value))
+		return -EINVAL;
+
+	ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
+	if (ret)
+		return ret;
+
+	ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
+			   size_cells);
+	if (ret)
+		return ret;
+
+	ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
+			  entry_size);
+	if (ret < 0)
+		return -EINVAL;
+
+	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
+			      image->arch.ima_buffer_size);
+	if (ret)
+		return -EINVAL;
+
+	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
diff --git a/arch/powerpc/kexec/relocate_32.S b/arch/powerpc/kexec/relocate_32.S
new file mode 100644
index 000000000000..61946c19e07c
--- /dev/null
+++ b/arch/powerpc/kexec/relocate_32.S
@@ -0,0 +1,500 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * This file contains kexec low-level functions.
+ *
+ * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
+ * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
+ * PPC44x port. Copyright (C) 2011,  IBM Corporation
+ * 		Author: Suzuki Poulose <suzuki@in.ibm.com>
+ */
+
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/ppc_asm.h>
+#include <asm/kexec.h>
+
+	.text
+
+	/*
+	 * Must be relocatable PIC code callable as a C function.
+	 */
+	.globl relocate_new_kernel
+relocate_new_kernel:
+	/* r3 = page_list   */
+	/* r4 = reboot_code_buffer */
+	/* r5 = start_address      */
+
+#ifdef CONFIG_FSL_BOOKE
+
+	mr	r29, r3
+	mr	r30, r4
+	mr	r31, r5
+
+#define ENTRY_MAPPING_KEXEC_SETUP
+#include <kernel/fsl_booke_entry_mapping.S>
+#undef ENTRY_MAPPING_KEXEC_SETUP
+
+	mr      r3, r29
+	mr      r4, r30
+	mr      r5, r31
+
+	li	r0, 0
+#elif defined(CONFIG_44x)
+
+	/* Save our parameters */
+	mr	r29, r3
+	mr	r30, r4
+	mr	r31, r5
+
+#ifdef CONFIG_PPC_47x
+	/* Check for 47x cores */
+	mfspr	r3,SPRN_PVR
+	srwi	r3,r3,16
+	cmplwi	cr0,r3,PVR_476FPE@h
+	beq	setup_map_47x
+	cmplwi	cr0,r3,PVR_476@h
+	beq	setup_map_47x
+	cmplwi	cr0,r3,PVR_476_ISS@h
+	beq	setup_map_47x
+#endif /* CONFIG_PPC_47x */
+
+/*
+ * Code for setting up 1:1 mapping for PPC440x for KEXEC
+ *
+ * We cannot switch off the MMU on PPC44x.
+ * So we:
+ * 1) Invalidate all the mappings except the one we are running from.
+ * 2) Create a tmp mapping for our code in the other address space(TS) and
+ *    jump to it. Invalidate the entry we started in.
+ * 3) Create a 1:1 mapping for 0-2GiB in chunks of 256M in original TS.
+ * 4) Jump to the 1:1 mapping in original TS.
+ * 5) Invalidate the tmp mapping.
+ *
+ * - Based on the kexec support code for FSL BookE
+ *
+ */
+
+	/*
+	 * Load the PID with kernel PID (0).
+	 * Also load our MSR_IS and TID to MMUCR for TLB search.
+	 */
+	li	r3, 0
+	mtspr	SPRN_PID, r3
+	mfmsr	r4
+	andi.	r4,r4,MSR_IS@l
+	beq	wmmucr
+	oris	r3,r3,PPC44x_MMUCR_STS@h
+wmmucr:
+	mtspr	SPRN_MMUCR,r3
+	sync
+
+	/*
+	 * Invalidate all the TLB entries except the current entry
+	 * where we are running from
+	 */
+	bl	0f				/* Find our address */
+0:	mflr	r5				/* Make it accessible */
+	tlbsx	r23,0,r5			/* Find entry we are in */
+	li	r4,0				/* Start at TLB entry 0 */
+	li	r3,0				/* Set PAGEID inval value */
+1:	cmpw	r23,r4				/* Is this our entry? */
+	beq	skip				/* If so, skip the inval */
+	tlbwe	r3,r4,PPC44x_TLB_PAGEID		/* If not, inval the entry */
+skip:
+	addi	r4,r4,1				/* Increment */
+	cmpwi	r4,64				/* Are we done?	*/
+	bne	1b				/* If not, repeat */
+	isync
+
+	/* Create a temp mapping and jump to it */
+	andi.	r6, r23, 1		/* Find the index to use */
+	addi	r24, r6, 1		/* r24 will contain 1 or 2 */
+
+	mfmsr	r9			/* get the MSR */
+	rlwinm	r5, r9, 27, 31, 31	/* Extract the MSR[IS] */
+	xori	r7, r5, 1		/* Use the other address space */
+
+	/* Read the current mapping entries */
+	tlbre	r3, r23, PPC44x_TLB_PAGEID
+	tlbre	r4, r23, PPC44x_TLB_XLAT
+	tlbre	r5, r23, PPC44x_TLB_ATTRIB
+
+	/* Save our current XLAT entry */
+	mr	r25, r4
+
+	/* Extract the TLB PageSize */
+	li	r10, 1 			/* r10 will hold PageSize */
+	rlwinm	r11, r3, 0, 24, 27	/* bits 24-27 */
+
+	/* XXX: As of now we use 256M, 4K pages */
+	cmpwi	r11, PPC44x_TLB_256M
+	bne	tlb_4k
+	rotlwi	r10, r10, 28		/* r10 = 256M */
+	b	write_out
+tlb_4k:
+	cmpwi	r11, PPC44x_TLB_4K
+	bne	default
+	rotlwi	r10, r10, 12		/* r10 = 4K */
+	b	write_out
+default:
+	rotlwi	r10, r10, 10		/* r10 = 1K */
+
+write_out:
+	/*
+	 * Write out the tmp 1:1 mapping for this code in other address space
+	 * Fixup  EPN = RPN , TS=other address space
+	 */
+	insrwi	r3, r7, 1, 23		/* Bit 23 is TS for PAGEID field */
+
+	/* Write out the tmp mapping entries */
+	tlbwe	r3, r24, PPC44x_TLB_PAGEID
+	tlbwe	r4, r24, PPC44x_TLB_XLAT
+	tlbwe	r5, r24, PPC44x_TLB_ATTRIB
+
+	subi	r11, r10, 1		/* PageOffset Mask = PageSize - 1 */
+	not	r10, r11		/* Mask for PageNum */
+
+	/* Switch to other address space in MSR */
+	insrwi	r9, r7, 1, 26		/* Set MSR[IS] = r7 */
+
+	bl	1f
+1:	mflr	r8
+	addi	r8, r8, (2f-1b)		/* Find the target offset */
+
+	/* Jump to the tmp mapping */
+	mtspr	SPRN_SRR0, r8
+	mtspr	SPRN_SRR1, r9
+	rfi
+
+2:
+	/* Invalidate the entry we were executing from */
+	li	r3, 0
+	tlbwe	r3, r23, PPC44x_TLB_PAGEID
+
+	/* attribute fields. rwx for SUPERVISOR mode */
+	li	r5, 0
+	ori	r5, r5, (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G)
+
+	/* Create 1:1 mapping in 256M pages */
+	xori	r7, r7, 1			/* Revert back to Original TS */
+
+	li	r8, 0				/* PageNumber */
+	li	r6, 3				/* TLB Index, start at 3  */
+
+next_tlb:
+	rotlwi	r3, r8, 28			/* Create EPN (bits 0-3) */
+	mr	r4, r3				/* RPN = EPN  */
+	ori	r3, r3, (PPC44x_TLB_VALID | PPC44x_TLB_256M) /* SIZE = 256M, Valid */
+	insrwi	r3, r7, 1, 23			/* Set TS from r7 */
+
+	tlbwe	r3, r6, PPC44x_TLB_PAGEID	/* PageID field : EPN, V, SIZE */
+	tlbwe	r4, r6, PPC44x_TLB_XLAT		/* Address translation : RPN   */
+	tlbwe	r5, r6, PPC44x_TLB_ATTRIB	/* Attributes */
+
+	addi	r8, r8, 1			/* Increment PN */
+	addi	r6, r6, 1			/* Increment TLB Index */
+	cmpwi	r8, 8				/* Are we done ? */
+	bne	next_tlb
+	isync
+
+	/* Jump to the new mapping 1:1 */
+	li	r9,0
+	insrwi	r9, r7, 1, 26			/* Set MSR[IS] = r7 */
+
+	bl	1f
+1:	mflr	r8
+	and	r8, r8, r11			/* Get our offset within page */
+	addi	r8, r8, (2f-1b)
+
+	and	r5, r25, r10			/* Get our target PageNum */
+	or	r8, r8, r5			/* Target jump address */
+
+	mtspr	SPRN_SRR0, r8
+	mtspr	SPRN_SRR1, r9
+	rfi
+2:
+	/* Invalidate the tmp entry we used */
+	li	r3, 0
+	tlbwe	r3, r24, PPC44x_TLB_PAGEID
+	sync
+	b	ppc44x_map_done
+
+#ifdef CONFIG_PPC_47x
+
+	/* 1:1 mapping for 47x */
+
+setup_map_47x:
+
+	/*
+	 * Load the kernel pid (0) to PID and also to MMUCR[TID].
+	 * Also set the MSR IS->MMUCR STS
+	 */
+	li	r3, 0
+	mtspr	SPRN_PID, r3			/* Set PID */
+	mfmsr	r4				/* Get MSR */
+	andi.	r4, r4, MSR_IS@l		/* TS=1? */
+	beq	1f				/* If not, leave STS=0 */
+	oris	r3, r3, PPC47x_MMUCR_STS@h	/* Set STS=1 */
+1:	mtspr	SPRN_MMUCR, r3			/* Put MMUCR */
+	sync
+
+	/* Find the entry we are running from */
+	bl	2f
+2:	mflr	r23
+	tlbsx	r23, 0, r23
+	tlbre	r24, r23, 0			/* TLB Word 0 */
+	tlbre	r25, r23, 1			/* TLB Word 1 */
+	tlbre	r26, r23, 2			/* TLB Word 2 */
+
+
+	/*
+	 * Invalidates all the tlb entries by writing to 256 RPNs(r4)
+	 * of 4k page size in all  4 ways (0-3 in r3).
+	 * This would invalidate the entire UTLB including the one we are
+	 * running from. However the shadow TLB entries would help us
+	 * to continue the execution, until we flush them (rfi/isync).
+	 */
+	addis	r3, 0, 0x8000			/* specify the way */
+	addi	r4, 0, 0			/* TLB Word0 = (EPN=0, VALID = 0) */
+	addi	r5, 0, 0
+	b	clear_utlb_entry
+
+	/* Align the loop to speed things up. from head_44x.S */
+	.align	6
+
+clear_utlb_entry:
+
+	tlbwe	r4, r3, 0
+	tlbwe	r5, r3, 1
+	tlbwe	r5, r3, 2
+	addis	r3, r3, 0x2000			/* Increment the way */
+	cmpwi	r3, 0
+	bne	clear_utlb_entry
+	addis	r3, 0, 0x8000
+	addis	r4, r4, 0x100			/* Increment the EPN */
+	cmpwi	r4, 0
+	bne	clear_utlb_entry
+
+	/* Create the entries in the other address space */
+	mfmsr	r5
+	rlwinm	r7, r5, 27, 31, 31		/* Get the TS (Bit 26) from MSR */
+	xori	r7, r7, 1			/* r7 = !TS */
+
+	insrwi	r24, r7, 1, 21			/* Change the TS in the saved TLB word 0 */
+
+	/*
+	 * write out the TLB entries for the tmp mapping
+	 * Use way '0' so that we could easily invalidate it later.
+	 */
+	lis	r3, 0x8000			/* Way '0' */
+
+	tlbwe	r24, r3, 0
+	tlbwe	r25, r3, 1
+	tlbwe	r26, r3, 2
+
+	/* Update the msr to the new TS */
+	insrwi	r5, r7, 1, 26
+
+	bl	1f
+1:	mflr	r6
+	addi	r6, r6, (2f-1b)
+
+	mtspr	SPRN_SRR0, r6
+	mtspr	SPRN_SRR1, r5
+	rfi
+
+	/*
+	 * Now we are in the tmp address space.
+	 * Create a 1:1 mapping for 0-2GiB in the original TS.
+	 */
+2:
+	li	r3, 0
+	li	r4, 0				/* TLB Word 0 */
+	li	r5, 0				/* TLB Word 1 */
+	li	r6, 0
+	ori	r6, r6, PPC47x_TLB2_S_RWX	/* TLB word 2 */
+
+	li	r8, 0				/* PageIndex */
+
+	xori	r7, r7, 1			/* revert back to original TS */
+
+write_utlb:
+	rotlwi	r5, r8, 28			/* RPN = PageIndex * 256M */
+						/* ERPN = 0 as we don't use memory above 2G */
+
+	mr	r4, r5				/* EPN = RPN */
+	ori	r4, r4, (PPC47x_TLB0_VALID | PPC47x_TLB0_256M)
+	insrwi	r4, r7, 1, 21			/* Insert the TS to Word 0 */
+
+	tlbwe	r4, r3, 0			/* Write out the entries */
+	tlbwe	r5, r3, 1
+	tlbwe	r6, r3, 2
+	addi	r8, r8, 1
+	cmpwi	r8, 8				/* Have we completed ? */
+	bne	write_utlb
+
+	/* make sure we complete the TLB write up */
+	isync
+
+	/*
+	 * Prepare to jump to the 1:1 mapping.
+	 * 1) Extract page size of the tmp mapping
+	 *    DSIZ = TLB_Word0[22:27]
+	 * 2) Calculate the physical address of the address
+	 *    to jump to.
+	 */
+	rlwinm	r10, r24, 0, 22, 27
+
+	cmpwi	r10, PPC47x_TLB0_4K
+	bne	0f
+	li	r10, 0x1000			/* r10 = 4k */
+	bl	1f
+
+0:
+	/* Defaults to 256M */
+	lis	r10, 0x1000
+
+	bl	1f
+1:	mflr	r4
+	addi	r4, r4, (2f-1b)			/* virtual address  of 2f */
+
+	subi	r11, r10, 1			/* offsetmask = Pagesize - 1 */
+	not	r10, r11			/* Pagemask = ~(offsetmask) */
+
+	and	r5, r25, r10			/* Physical page */
+	and	r6, r4, r11			/* offset within the current page */
+
+	or	r5, r5, r6			/* Physical address for 2f */
+
+	/* Switch the TS in MSR to the original one */
+	mfmsr	r8
+	insrwi	r8, r7, 1, 26
+
+	mtspr	SPRN_SRR1, r8
+	mtspr	SPRN_SRR0, r5
+	rfi
+
+2:
+	/* Invalidate the tmp mapping */
+	lis	r3, 0x8000			/* Way '0' */
+
+	clrrwi	r24, r24, 12			/* Clear the valid bit */
+	tlbwe	r24, r3, 0
+	tlbwe	r25, r3, 1
+	tlbwe	r26, r3, 2
+
+	/* Make sure we complete the TLB write and flush the shadow TLB */
+	isync
+
+#endif
+
+ppc44x_map_done:
+
+
+	/* Restore the parameters */
+	mr	r3, r29
+	mr	r4, r30
+	mr	r5, r31
+
+	li	r0, 0
+#else
+	li	r0, 0
+
+	/*
+	 * Set Machine Status Register to a known status,
+	 * switch the MMU off and jump to 1: in a single step.
+	 */
+
+	mr	r8, r0
+	ori     r8, r8, MSR_RI|MSR_ME
+	mtspr	SPRN_SRR1, r8
+	addi	r8, r4, 1f - relocate_new_kernel
+	mtspr	SPRN_SRR0, r8
+	sync
+	rfi
+
+1:
+#endif
+	/* from this point address translation is turned off */
+	/* and interrupts are disabled */
+
+	/* set a new stack at the bottom of our page... */
+	/* (not really needed now) */
+	addi	r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */
+	stw	r0, 0(r1)
+
+	/* Do the copies */
+	li	r6, 0 /* checksum */
+	mr	r0, r3
+	b	1f
+
+0:	/* top, read another word for the indirection page */
+	lwzu	r0, 4(r3)
+
+1:
+	/* is it a destination page? (r8) */
+	rlwinm.	r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
+	beq	2f
+
+	rlwinm	r8, r0, 0, 0, 19 /* clear kexec flags, page align */
+	b	0b
+
+2:	/* is it an indirection page? (r3) */
+	rlwinm.	r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
+	beq	2f
+
+	rlwinm	r3, r0, 0, 0, 19 /* clear kexec flags, page align */
+	subi	r3, r3, 4
+	b	0b
+
+2:	/* are we done? */
+	rlwinm.	r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
+	beq	2f
+	b	3f
+
+2:	/* is it a source page? (r9) */
+	rlwinm.	r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
+	beq	0b
+
+	rlwinm	r9, r0, 0, 0, 19 /* clear kexec flags, page align */
+
+	li	r7, PAGE_SIZE / 4
+	mtctr   r7
+	subi    r9, r9, 4
+	subi    r8, r8, 4
+9:
+	lwzu    r0, 4(r9)  /* do the copy */
+	xor	r6, r6, r0
+	stwu    r0, 4(r8)
+	dcbst	0, r8
+	sync
+	icbi	0, r8
+	bdnz    9b
+
+	addi    r9, r9, 4
+	addi    r8, r8, 4
+	b	0b
+
+3:
+
+	/* To be certain of avoiding problems with self-modifying code
+	 * execute a serializing instruction here.
+	 */
+	isync
+	sync
+
+	mfspr	r3, SPRN_PIR /* current core we are running on */
+	mr	r4, r5 /* load physical address of chunk called */
+
+	/* jump to the entry point, usually the setup routine */
+	mtlr	r5
+	blrl
+
+1:	b	1b
+
+relocate_new_kernel_end:
+
+	.globl relocate_new_kernel_size
+relocate_new_kernel_size:
+	.long relocate_new_kernel_end - relocate_new_kernel