Experimental Kexec hardboot patch for Melius

kexec-melius.patch

From 60ee12283c6be1540135f8470ae42f85cc4baebe Mon Sep 17 00:00:00 2001
From: Mike Kasick <mike@kasick.org>
Date: Sat, 7 Jul 2012 19:00:47 -0400
Subject: [PATCH] Add and enable kexec hardboot support.

Consists of squashed commits from:
https://github.com/mkasick/android_kernel_samsung_jfltespr.git

commit 750bb80f2854d6af5273e55ea179a4c60b2d9efc
Author: Mike Kasick <mike@kasick.org>
Date:   Sun Jun 2 23:11:24 2013 -0400

    Clear download mode flag on kexec hardboot.

commit 138ba851ee949af291eae914f410aea2d85ed9f5
Author: Mike Kasick <mike@kasick.org>
Date:   Sun May 12 22:39:26 2013 -0400

    Support hard booting to a kexec kernel.

    See KEXEC_HARDBOOT config option help for details.

commit 3ab41019a7af08395c233bebb605c2f1ea49c8e0
Author: Mike Kasick <mike@kasick.org>
Date:   Sat Jul 7 23:10:24 2012 -0400

    Support copying of kernel tagged list (atags) in the decompressor.

    This is needed to hardboot kexec a kernel with a new tags list (including a
    new kernel command line), since the new atags would otherwise be lost with
    the limited kernel memory mapping.  Without this patch, a hardboot-kexec'd
    kernel uses the atags provided by the bootloader.

commit 446c3d7a6631877f7dc9142359cf0eae300e9a08
Author: Mike Kasick <mike@kasick.org>
Date:   Sat Jul 7 23:09:39 2012 -0400

    Enable caching and buffering for all of physical RAM in the decompressor.

    Old method is to enable caching and buffering only for the 256 MB at the
    start of the decompressor image.  This makes a hardboot-kexec'd kernel very
    slow to decompress since the decompressor is located far above the kernel
    destination.  This patch reduces boot time from 35 to 8 seconds on epicmtd.

commit d3646be88f5b1f9a8ae714c922ec50c681b7157f
Author: Mike Kasick <mike@kasick.org>
Date:   Sat Jul 7 19:00:47 2012 -0400

    Enable and fix kexec syscall support.

    Use mem_text_write_kernel_word when assigning reboot_code_buffer parameters
    to avoid protection faults (writes to read-only kernel memory) when
    CONFIG_STRICT_MEMORY_RWX is enabled.

Change-Id: I0400ad00fcf02b8ad017f8aa371724a659b930b4
Signed-off-by: Willi Ye <williye97@gmail.com>

Conflicts:
	arch/arm/configs/cyanogen_jf_defconfig

Conflicts:
	Makefile
	arch/arm/mach-msm/board-jf_att.c
	arch/arm/mach-msm/board-jf_cri.c
	arch/arm/mach-msm/board-jf_dcm.c
	arch/arm/mach-msm/board-jf_eur.c
	arch/arm/mach-msm/board-jf_ktt.c
	arch/arm/mach-msm/board-jf_lgt.c
	arch/arm/mach-msm/board-jf_skt.c
	arch/arm/mach-msm/board-jf_spr.c
	arch/arm/mach-msm/board-jf_tmo.c
	arch/arm/mach-msm/board-jf_usc.c
	arch/arm/mach-msm/board-jf_vzw.c
	build_master.sh
---
 arch/arm/Kconfig                        | 30 ++++++++++++++
 arch/arm/boot/compressed/Makefile       |  3 ++
 arch/arm/boot/compressed/head.S         | 73 ++++++++++++++++++++++++++++++++-
 arch/arm/boot/compressed/misc.c         | 24 +++++++++++
 arch/arm/configs/gk_melius_defconfig    |  3 ++
 arch/arm/include/asm/kexec.h            |  9 ++++
 arch/arm/kernel/machine_kexec.c         | 23 +++++++++--
 arch/arm/kernel/relocate_kernel.S       | 53 ++++++++++++++++++++++++
 arch/arm/mach-msm/Kconfig               |  7 ++++
 arch/arm/mach-msm/Makefile.boot         |  3 ++
 arch/arm/mach-msm/board-melius.c        | 30 ++++++++++----
 arch/arm/mach-msm/include/mach/memory.h |  3 ++
 arch/arm/mach-msm/restart.c             | 24 +++++++++++
 include/linux/kexec.h                   | 16 ++++++--
 kernel/kexec.c                          |  4 ++
 15 files changed, 288 insertions(+), 17 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index ab1716a..2cc63a0 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -2249,6 +2249,36 @@ config ATAGS_PROC
 	  Should the atags used to boot the kernel be exported in an "atags"
 	  file in procfs. Useful with kexec.
 
+config KEXEC_HARDBOOT
+	bool "Support hard booting to a kexec kernel"
+	depends on KEXEC
+	help
+	  Allows hard booting (i.e., with a full hardware reboot) to a kernel
+	  previously loaded in memory by kexec.  This works around the problem of
+	  soft-booted kernel hangs due to improper device shutdown and/or
+	  reinitialization.  Support is comprised of two components:
+
+	  First, a "hardboot" flag is added to the kexec syscall to force a hard
+	  reboot in relocate_new_kernel() (which requires machine-specific assembly
+	  code).  This also requires the kexec userspace tool to load the kexec'd
+	  kernel in memory region left untouched by the bootloader (i.e., not
+	  explicitly cleared and not overwritten by the boot kernel).  Just prior
+	  to reboot, the kexec kernel arguments are stashed in a machine-specific
+	  memory page that must also be preserved.  Note that this hardboot page
+	  need not be reserved during regular kernel execution.
+
+	  Second, the zImage decompresor of the boot (bootloader-loaded) kernel is
+	  modified to check the hardboot page for fresh kexec arguments, and if
+	  present, attempts to jump to the kexec'd kernel preserved in memory.
+
+	  Note that hardboot support is only required in the boot kernel and any
+	  kernel capable of performing a hardboot kexec.  It is _not_ required by a
+	  kexec'd kernel.
+
+config KEXEC_HB_PAGE_ADDR
+	hex "Kexec hardboot page address"
+	depends on KEXEC_HARDBOOT
+
 config CRASH_DUMP
 	bool "Build kdump crash kernel (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index bb26756..b3f5924 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -139,6 +139,9 @@ endif
 ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 LDFLAGS_vmlinux += --be8
 endif
+ifneq ($(PARAMS_PHYS),)
+LDFLAGS_vmlinux += --defsym params_phys=$(PARAMS_PHYS)
+endif
 # ?
 LDFLAGS_vmlinux += -p
 # Report unresolved symbol references
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 64a6d6f..f046756 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -9,6 +9,11 @@
  * published by the Free Software Foundation.
  */
 #include <linux/linkage.h>
+#include <asm/memory.h>
+
+#ifdef CONFIG_KEXEC_HARDBOOT
+#include <asm/kexec.h>
+#endif
 
 /*
  * Debugging stuff
@@ -133,7 +138,31 @@ start:
 		.word	_edata			@ zImage end address
  THUMB(		.thumb			)
 1:		mov	r7, r1			@ save architecture ID
-		mov	r8, r2			@ save atags pointer
+		teq	r0, #0			@ Check for kexec_boot_atags.
+		movne	r8, r0			@ Save kexec_boot_tags.
+		moveq	r8, r2			@ save atags pointer
+
+#ifdef CONFIG_KEXEC_HARDBOOT
+		/* Check hardboot page for a kexec kernel. */
+		ldr	r3, =KEXEC_HB_PAGE_ADDR
+		ldr	r0, [r3]
+		ldr	r1, =KEXEC_HB_PAGE_MAGIC
+		teq	r0, r1
+		bne	not_booting_other
+
+		/* Clear hardboot page magic to avoid boot loop. */
+		mov	r0, #0
+		str	r0, [r3]
+
+		/* Load boot arguments and jump to kexec kernel. */
+		ldr	r0, [r3, #12]	@ kexec_boot_atags (r2: boot_atags)
+		ldr	r1, [r3, #8]	@ kexec_mach_type
+		ldr	pc, [r3, #4]	@ kexec_start_address
+
+		.ltorg
+
+not_booting_other:
+#endif
 
 #ifndef __ARM_ARCH_2__
 		/*
@@ -456,6 +485,41 @@ not_relocated:	mov	r0, #0
 		add	r2, sp, #0x10000	@ 64k max
 		mov	r3, r7
 		bl	decompress_kernel
+
+/* Copy the kernel tagged list (atags):
+ *
+ * The kernel requires atags to be located in a direct-mapped region,
+ * usually below the kernel in the first 16 kB of RAM.  If they're above
+ * (the start of) the kernel, they need to be copied to a suitable
+ * location, e.g., the machine-defined params_phys.
+ *
+ * Still need to make sure that the copied tags don't overwrite either the
+ * kernel or decompressor code (or rather, the remainder of it since
+ * everything up to here has already been executed).
+ *
+ * r4: zreladdr (kernel start)
+ * r8: atags */
+
+		/* Don't need to copy atags if they're already below the kernel. */
+		cmp	r8, r4
+		blo	call_kernel
+
+		/* r1: min(zreladdr, pc) */
+		mov	r1, pc
+		cmp	r4, r1
+		movlo	r1, r4
+
+		/* Compute max space for atags, if max <= 0 don't copy. */
+		ldr	r0, =params_phys	@ dest
+		subs	r2, r1, r0		@ max = min(zreladdr, pc) - dest
+		bls	call_kernel
+
+		/* Copy atags to params_phys. */
+		mov	r1, r8			@ src
+		bl	copy_atags
+		mov	r8, r0
+
+call_kernel:
 		bl	cache_clean_flush
 		bl	cache_off
 		mov	r0, #0			@ must be zero
@@ -464,6 +528,8 @@ not_relocated:	mov	r0, #0
  ARM(		mov	pc, r4	)		@ call kernel
  THUMB(		bx	r4	)		@ entry point is always ARM
 
+		.ltorg
+
 		.align	2
 		.type	LC0, #object
 LC0:		.word	LC0			@ r1
@@ -581,9 +647,14 @@ __setup_mmu:	sub	r3, r4, #16384		@ Page directory size
  * bits for the RAM area only.
  */
 		mov	r0, r3
+#if defined(PLAT_PHYS_OFFSET) && defined(END_MEM)
+		ldr	r9, =PLAT_PHYS_OFFSET	@ start of RAM
+		ldr	r10, =END_MEM		@ end of RAM
+#else
 		mov	r9, r0, lsr #18
 		mov	r9, r9, lsl #18		@ start of RAM
 		add	r10, r9, #0x10000000	@ a reasonable RAM size
+#endif
 		mov	r1, #0x12		@ XN|U + section mapping
 		orr	r1, r1, #3 << 10	@ AP=11
 		add	r2, r3, #16384
diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c
index 8e2a8fc..112edae 100644
--- a/arch/arm/boot/compressed/misc.c
+++ b/arch/arm/boot/compressed/misc.c
@@ -21,6 +21,8 @@
 #include <linux/compiler.h>	/* for inline */
 #include <linux/types.h>
 #include <linux/linkage.h>
+#include <asm/setup.h>
+#include <asm/string.h>
 
 static void putstr(const char *ptr);
 extern void error(char *x);
@@ -152,3 +154,25 @@ asmlinkage void __div0(void)
 	else
 		putstr(" done, booting the kernel.\n");
 }
+
+const struct tag *copy_atags(struct tag *dest, const struct tag *src,
+                             size_t max)
+{
+	struct tag *tag;
+	size_t      size;
+
+	/* Find the last tag (ATAG_NONE). */
+	for_each_tag(tag, (struct tag *)src)
+		continue;
+
+	/* Include the last tag in copy. */
+	size = (char *)tag - (char *)src + sizeof(struct tag_header);
+
+	/* If there's not enough room, just use original and hope it works. */
+	if (size > max)
+		return src;
+
+	memcpy(dest, src, size);
+
+	return dest;
+}
diff --git a/arch/arm/configs/gk_melius_defconfig b/arch/arm/configs/gk_melius_defconfig
index 64fd30e..b57167a 100644
--- a/arch/arm/configs/gk_melius_defconfig
+++ b/arch/arm/configs/gk_melius_defconfig
@@ -419,6 +419,8 @@ CONFIG_BOARD_HEADER_FILE=""
 # CONFIG_LGE_CRASH_HANDLER is not set
 # CONFIG_MSM_STACKED_MEMORY is not set
 # CONFIG_RTC_AUTO_PWRON is not set
+CONFIG_HAVE_END_MEM=y
+CONFIG_END_MEM=0xffffffff
 CONFIG_KERNEL_MSM_CONTIG_MEM_REGION=y
 CONFIG_MSM_AMSS_VERSION=6225
 # CONFIG_MSM_AMSS_VERSION_6210 is not set
@@ -731,6 +733,7 @@ CONFIG_CMDLINE=""
 CONFIG_KEXEC=y
 CONFIG_ATAGS_PROC=y
 CONFIG_KEXEC_HARDBOOT=y
+CONFIG_KEXEC_HB_PAGE_ADDR=0x88400000
 # CONFIG_CRASH_DUMP is not set
 # CONFIG_AUTO_ZRELADDR is not set
 
diff --git a/arch/arm/include/asm/kexec.h b/arch/arm/include/asm/kexec.h
index c2b9b4b..632bc15 100644
--- a/arch/arm/include/asm/kexec.h
+++ b/arch/arm/include/asm/kexec.h
@@ -17,6 +17,11 @@
 #define KEXEC_ARM_ATAGS_OFFSET  0x1000
 #define KEXEC_ARM_ZIMAGE_OFFSET 0x8000
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+#define KEXEC_HB_PAGE_ADDR  UL(CONFIG_KEXEC_HB_PAGE_ADDR)
+#define KEXEC_HB_PAGE_MAGIC 0x4a5db007
+#endif
+
 #ifndef __ASSEMBLY__
 
 /**
@@ -53,6 +58,10 @@ static inline void crash_setup_regs(struct pt_regs *newregs,
 /* Function pointer to optional machine-specific reinitialization */
 extern void (*kexec_reinit)(void);
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+extern void (*kexec_hardboot_hook)(void);
+#endif
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* CONFIG_KEXEC */
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index dfcdb9f..5882128 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -14,6 +14,7 @@
 #include <asm/cacheflush.h>
 #include <asm/mach-types.h>
 #include <asm/system_misc.h>
+#include <asm/mmu_writeable.h>
 
 extern const unsigned char relocate_new_kernel[];
 extern const unsigned int relocate_new_kernel_size;
@@ -23,6 +24,11 @@
 extern unsigned long kexec_mach_type;
 extern unsigned long kexec_boot_atags;
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+extern unsigned long kexec_hardboot;
+void (*kexec_hardboot_hook)(void);
+#endif
+
 static atomic_t waiting_for_crash_ipi;
 
 /*
@@ -119,10 +125,13 @@ void machine_kexec(struct kimage *image)
 	reboot_code_buffer = page_address(image->control_code_page);
 
 	/* Prepare parameters for reboot_code_buffer*/
-	kexec_start_address = image->start;
-	kexec_indirection_page = page_list;
-	kexec_mach_type = machine_arch_type;
-	kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
+	mem_text_write_kernel_word(&kexec_start_address, image->start);
+	mem_text_write_kernel_word(&kexec_indirection_page, page_list);
+	mem_text_write_kernel_word(&kexec_mach_type, machine_arch_type);
+	mem_text_write_kernel_word(&kexec_boot_atags, image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET);
+#ifdef CONFIG_KEXEC_HARDBOOT
+	mem_text_write_kernel_word(&kexec_hardboot, image->hardboot);
+#endif
 
 	/* copy our kernel relocation code to the control code page */
 	memcpy(reboot_code_buffer,
@@ -136,5 +145,11 @@ void machine_kexec(struct kimage *image)
 	if (kexec_reinit)
 		kexec_reinit();
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+	if (image->hardboot && kexec_hardboot_hook)
+		/* Run any final machine-specific shutdown code. */
+		kexec_hardboot_hook();
+#endif
+
 	soft_restart(reboot_code_buffer_phys);
 }
diff --git a/arch/arm/kernel/relocate_kernel.S b/arch/arm/kernel/relocate_kernel.S
index d0cdedf..1e44841 100644
--- a/arch/arm/kernel/relocate_kernel.S
+++ b/arch/arm/kernel/relocate_kernel.S
@@ -4,6 +4,13 @@
 
 #include <asm/kexec.h>
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+#include <asm/memory.h>
+#if defined(CONFIG_ARCH_MSM8960) || defined(CONFIG_ARCH_APQ8064)
+#include <mach/msm_iomap.h>
+#endif
+#endif
+
 	.globl relocate_new_kernel
 relocate_new_kernel:
 
@@ -52,6 +59,12 @@ relocate_new_kernel:
 	b 0b
 
 2:
+#ifdef CONFIG_KEXEC_HARDBOOT
+	ldr	r0, kexec_hardboot
+	teq	r0, #0
+	bne	hardboot
+#endif
+
 	/* Jump to relocated kernel */
 	mov lr,r1
 	mov r0,#0
@@ -60,6 +73,40 @@ relocate_new_kernel:
  ARM(	mov pc, lr	)
  THUMB(	bx lr		)
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+hardboot:
+	/* Stash boot arguments in hardboot page:
+	 *  0: KEXEC_HB_PAGE_MAGIC
+	 *  4: kexec_start_address
+	 *  8: kexec_mach_type
+	 * 12: kexec_boot_atags */
+	ldr	r0, =KEXEC_HB_PAGE_ADDR
+	str	r1, [r0, #4]
+	ldr	r1, kexec_mach_type
+	str	r1, [r0, #8]
+	ldr	r1, kexec_boot_atags
+	str	r1, [r0, #12]
+	ldr	r1, =KEXEC_HB_PAGE_MAGIC
+	str	r1, [r0]
+
+#if defined(CONFIG_ARCH_MSM8960) || defined(CONFIG_ARCH_APQ8064)
+#if defined(CONFIG_ARCH_APQ8064)
+#define MSM_TLMM_PHYS APQ8064_TLMM_PHYS
+#elif defined(CONFIG_ARCH_MSM8960)
+#define MSM_TLMM_PHYS MSM8960_TLMM_PHYS
+#endif
+	/* Hard reset via PMIC, decompressor jumps to kernel. */
+	ldr	r0, =MSM_TLMM_PHYS
+	mov	r1, #0
+	str	r1, [r0, #0x820]  @ PSHOLD_CTL_SU
+loop:	b	loop
+#else
+#error "No reboot method defined for hardboot."
+#endif
+
+	.ltorg
+#endif
+
 	.align
 
 	.globl kexec_start_address
@@ -79,6 +126,12 @@ kexec_mach_type:
 kexec_boot_atags:
 	.long	0x0
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+	.globl kexec_hardboot
+kexec_hardboot:
+	.long	0x0
+#endif
+
 relocate_new_kernel_end:
 
 	.globl relocate_new_kernel_size
diff --git a/arch/arm/mach-msm/Kconfig b/arch/arm/mach-msm/Kconfig
index 5243bbf..c41cb0d 100644
--- a/arch/arm/mach-msm/Kconfig
+++ b/arch/arm/mach-msm/Kconfig
@@ -1364,6 +1364,13 @@ config PHYS_OFFSET
 	default "0x40200000" if ARCH_MSM8X60
 	default "0x10000000"
 
+config HAVE_END_MEM
+	bool "Specify highest physical RAM address at compile time"
+
+config END_MEM
+	hex "Highest physical address where system RAM resides"
+	depends on HAVE_END_MEM
+
 config KERNEL_MSM_CONTIG_MEM_REGION
 	bool "Enable in-kernel contiguous memory region"
 	default y if ARCH_MSM8X60
diff --git a/arch/arm/mach-msm/Makefile.boot b/arch/arm/mach-msm/Makefile.boot
index b57d4e1..886c8c8 100644
--- a/arch/arm/mach-msm/Makefile.boot
+++ b/arch/arm/mach-msm/Makefile.boot
@@ -38,12 +38,15 @@ endif
 
 # MSM8960
    zreladdr-$(CONFIG_ARCH_MSM8960)	:= 0x80208000
+params_phys-$(CONFIG_ARCH_MSM8960)	:= 0x80200100
 
 # MSM8930
    zreladdr-$(CONFIG_ARCH_MSM8930)	:= 0x80208000
+params_phys-$(CONFIG_ARCH_MSM8930)  := 0x80200100
 
 # APQ8064
    zreladdr-$(CONFIG_ARCH_APQ8064)	:= 0x80208000
+params_phys-$(CONFIG_ARCH_APQ8064)	:= 0x80200100
 
 # MSM8974
    zreladdr-$(CONFIG_ARCH_MSM8974)	:= 0x00008000
diff --git a/arch/arm/mach-msm/board-melius.c b/arch/arm/mach-msm/board-melius.c
index 2c4a659..1ee78c7 100644
--- a/arch/arm/mach-msm/board-melius.c
+++ b/arch/arm/mach-msm/board-melius.c
@@ -137,6 +137,10 @@
 #include <mach/msm8930-thermistor.h>
 #endif
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+#include <asm/kexec.h>
+#endif
+
 #include "timer.h"
 #include "devices.h"
 #include "devices-msm8x60.h"
@@ -1861,19 +1865,27 @@ static void __init reserve_mem_for_ion(enum ion_memory_types mem_type,
 #endif
 
 #ifdef CONFIG_ANDROID_PERSISTENT_RAM
-#define RAMCONSOLE_PHYS_ADDR 0x8FE00000
+#define RAMCONSOLE_PHYS_ADDR 0x8FD00000
 static struct persistent_ram_descriptor per_ram_descs[] __initdata = {
-	{
-		.name = "ram_console",
-		.size = SZ_1M,
-	}
+    {
+        .name = "ram_console",
+#ifdef CONFIG_KEXEC_HARDBOOT
+        .size = KEXEC_HB_PAGE_ADDR - RAMCONSOLE_PHYS_ADDR,
+    },
+    {
+        .name = "kexec_hb_page",
+        .size = SZ_1M - (KEXEC_HB_PAGE_ADDR - RAMCONSOLE_PHYS_ADDR),
+#else
+        .size = SZ_1M,
+#endif
+    }
 };
 
 static struct persistent_ram per_ram __initdata = {
-	.descs = per_ram_descs,
-	.num_descs = ARRAY_SIZE(per_ram_descs),
-	.start = RAMCONSOLE_PHYS_ADDR,
-	.size = SZ_1M
+    .descs = per_ram_descs,
+    .num_descs = ARRAY_SIZE(per_ram_descs),
+    .start = RAMCONSOLE_PHYS_ADDR,
+    .size = SZ_1M
 };
 #endif
 
diff --git a/arch/arm/mach-msm/include/mach/memory.h b/arch/arm/mach-msm/include/mach/memory.h
index 18518b7..0e49743 100644
--- a/arch/arm/mach-msm/include/mach/memory.h
+++ b/arch/arm/mach-msm/include/mach/memory.h
@@ -19,6 +19,9 @@
 
 /* physical offset of RAM */
 #define PLAT_PHYS_OFFSET UL(CONFIG_PHYS_OFFSET)
+#ifdef CONFIG_HAVE_END_MEM
+#define END_MEM          UL(CONFIG_END_MEM)
+#endif
 
 #define MAX_PHYSMEM_BITS 32
 #define SECTION_SIZE_BITS 28
diff --git a/arch/arm/mach-msm/restart.c b/arch/arm/mach-msm/restart.c
index 0518f6e..07edb74 100644
--- a/arch/arm/mach-msm/restart.c
+++ b/arch/arm/mach-msm/restart.c
@@ -40,6 +40,10 @@
 #include "msm_watchdog.h"
 #include "timer.h"
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+#include <asm/kexec.h>
+#endif
+
 #define WDT0_RST	0x38
 #define WDT0_EN		0x40
 #define WDT0_BARK_TIME	0x4C
@@ -394,6 +398,23 @@ static int dload_mode_normal_reboot_handler(struct notifier_block *nb,
 };
 #endif
 
+#ifdef CONFIG_KEXEC_HARDBOOT
+void msm_kexec_hardboot(void)
+{
+#if defined(CONFIG_MSM_DLOAD_MODE) && !defined(CONFIG_SEC_DEBUG)
+	/* Do not enter download mode on reboot. */
+	set_dload_mode(0);
+#endif
+
+	/* Set PM8XXX PMIC to reset on power off. */
+	pm8xxx_reset_pwr_off(1);
+
+	/* Reboot with the recovery kernel since the boot kernel decompressor may
+	 * not support the hardboot jump. */
+	__raw_writel(0x77665502, restart_reason);
+}
+#endif
+
 static int __init msm_pmic_restart_init(void)
 {
 	int rc;
@@ -441,6 +462,9 @@ static int __init msm_restart_init(void)
 	restart_reason = MSM_IMEM_BASE + RESTART_REASON_ADDR;
 #endif
 	pm_power_off = msm_power_off;
+#ifdef CONFIG_KEXEC_HARDBOOT
+	kexec_hardboot_hook = msm_kexec_hardboot;
+#endif
 
 	return 0;
 }
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index af84a25..664791f 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -110,6 +110,9 @@ struct kimage {
 #define KEXEC_TYPE_DEFAULT 0
 #define KEXEC_TYPE_CRASH   1
 	unsigned int preserve_context : 1;
+#ifdef CONFIG_KEXEC_HARDBOOT
+	unsigned int hardboot : 1;
+#endif
 
 #ifdef ARCH_HAS_KIMAGE_ARCH
 	struct kimage_arch arch;
@@ -178,6 +181,9 @@ extern struct page *kimage_alloc_control_pages(struct kimage *image,
 
 #define KEXEC_ON_CRASH		0x00000001
 #define KEXEC_PRESERVE_CONTEXT	0x00000002
+#ifdef CONFIG_KEXEC_HARDBOOT
+#define KEXEC_HARDBOOT		0x00000004
+#endif
 #define KEXEC_ARCH_MASK		0xffff0000
 
 /* These values match the ELF architecture values.
@@ -196,10 +202,14 @@ extern struct page *kimage_alloc_control_pages(struct kimage *image,
 #define KEXEC_ARCH_MIPS    ( 8 << 16)
 
 /* List of defined/legal kexec flags */
-#ifndef CONFIG_KEXEC_JUMP
-#define KEXEC_FLAGS    KEXEC_ON_CRASH
-#else
+#if defined(CONFIG_KEXEC_JUMP) && defined(CONFIG_KEXEC_HARDBOOT)
+#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_HARDBOOT)
+#elif defined(CONFIG_KEXEC_JUMP)
 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
+#elif defined(CONFIG_KEXEC_HARDBOOT)
+#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_HARDBOOT)
+#else
+#define KEXEC_FLAGS    (KEXEC_ON_CRASH)
 #endif
 
 #define VMCOREINFO_BYTES           (4096)
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 4e2e472..aef7893 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1004,6 +1004,10 @@ static int kimage_load_segment(struct kimage *image,
 
 		if (flags & KEXEC_PRESERVE_CONTEXT)
 			image->preserve_context = 1;
+#ifdef CONFIG_KEXEC_HARDBOOT
+		if (flags & KEXEC_HARDBOOT)
+			image->hardboot = 1;
+#endif
 		result = machine_kexec_prepare(image);
 		if (result)
 			goto out;
-- 
1.8.5.1