Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux

Pull xtensa updates from Chris Zankel:
 "Support for the latest MMU architecture that allows for a larger
  accessible memory region, and various bug-fixes"

* tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux:
  xtensa: Switch to asm-generic/linkage.h
  xtensa: fix redboot load address
  xtensa: ISS: fix timer_lock usage in rs_open
  xtensa: disable IRQs while IRQ handler is running
  xtensa: enable lockdep support
  xtensa: fix arch_irqs_disabled_flags implementation
  xtensa: add irq flags trace support
  xtensa: provide custom CALLER_ADDR* implementations
  xtensa: add stacktrace support
  xtensa: clean up stpill_registers
  xtensa: don't use a7 in simcalls
  xtensa: don't attempt to use unconfigured timers
  xtensa: provide default platform_pcibios_init implementation
  xtensa: remove KCORE_ELF again
  xtensa: document MMUv3 setup sequence
  xtensa: add MMU v3 support
  xtensa: fix ibreakenable register update
  xtensa: fix oprofile building as module

32 files changed, 773 insertions, 254 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index acdfc615cca..0a1b95f81a3 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -1,11 +1,9 @@
-config FRAME_POINTER
-	def_bool n
-
 config ZONE_DMA
 	def_bool y
 
 config XTENSA
 	def_bool y
+	select ARCH_WANT_FRAME_POINTERS
 	select HAVE_IDE
 	select GENERIC_ATOMIC64
 	select HAVE_GENERIC_HARDIRQS
@@ -49,6 +47,15 @@ config HZ
 source "init/Kconfig"
 source "kernel/Kconfig.freezer"
 
+config LOCKDEP_SUPPORT
+	def_bool y
+
+config STACKTRACE_SUPPORT
+	def_bool y
+
+config TRACE_IRQFLAGS_SUPPORT
+	def_bool y
+
 config MMU
 	def_bool n
 
@@ -100,6 +107,35 @@ config MATH_EMULATION
 	help
 	Can we use information of configuration file?
 
+config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
+	bool "Initialize Xtensa MMU inside the Linux kernel code"
+	default y
+	help
+	  Earlier version initialized the MMU in the exception vector
+	  before jumping to _startup in head.S and had an advantage that
+	  it was possible to place a software breakpoint at 'reset' and
+	  then enter your normal kernel breakpoints once the MMU was mapped
+	  to the kernel mappings (0XC0000000).
+
+	  This unfortunately doesn't work for U-Boot and likley also wont
+	  work for using KEXEC to have a hot kernel ready for doing a
+	  KDUMP.
+
+	  So now the MMU is initialized in head.S but it's necessary to
+	  use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
+	  xt-gdb can't place a Software Breakpoint in the  0XD region prior
+	  to mapping the MMU and after mapping even if the area of low memory
+	  was mapped gdb wouldn't remove the breakpoint on hitting it as the
+	  PC wouldn't match. Since Hardware Breakpoints are recommended for
+	  Linux configurations it seems reasonable to just assume they exist
+	  and leave this older mechanism for unfortunate souls that choose
+	  not to follow Tensilica's recommendation.
+
+	  Selecting this will cause U-Boot to set the KERNEL Load and Entry
+	  address at 0x00003000 instead of the mapped std of 0xD0003000.
+
+	  If in doubt, say Y.
+
 endmenu
 
 config XTENSA_CALIBRATE_CCOUNT
@@ -249,21 +285,6 @@ endmenu
 
 menu "Executable file formats"
 
-# only elf supported
-config KCORE_ELF
-	def_bool y
-        depends on PROC_FS
-        help
-          If you enabled support for /proc file system then the file
-          /proc/kcore will contain the kernel core image in ELF format. This
-          can be used in gdb:
-
-          $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
-
-          This is especially useful if you have compiled the kernel with the
-          "-g" option to preserve debugging information. It is mainly used
-	  for examining kernel data structures on the live kernel.
-
 source "fs/Kconfig.binfmt"
 
 endmenu
diff --git a/arch/xtensa/boot/boot-elf/Makefile b/arch/xtensa/boot/boot-elf/Makefile
index 1fe01b78c12..89db089f5a1 100644
--- a/arch/xtensa/boot/boot-elf/Makefile
+++ b/arch/xtensa/boot/boot-elf/Makefile
@@ -12,6 +12,7 @@ endif
 
 export OBJCOPY_ARGS
 export CPPFLAGS_boot.lds += -P -C
+export KBUILD_AFLAGS += -mtext-section-literals
 
 boot-y		:= bootstrap.o
 
diff --git a/arch/xtensa/boot/boot-elf/boot.lds.S b/arch/xtensa/boot/boot-elf/boot.lds.S
index 7b646e0a648..932b58ef33d 100644
--- a/arch/xtensa/boot/boot-elf/boot.lds.S
+++ b/arch/xtensa/boot/boot-elf/boot.lds.S
@@ -1,41 +1,29 @@
-#include <variant/core.h>
+/*
+ *  linux/arch/xtensa/boot/boot-elf/boot.lds.S
+ *
+ *  Copyright (C) 2008 - 2013 by Tensilica Inc.
+ *
+ *  Chris Zankel <chris@zankel.net>
+ *  Marc Gauthier <marc@tensilica.com
+ *  Pete Delaney <piet@tensilica.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <asm/vectors.h>
 OUTPUT_ARCH(xtensa)
 ENTRY(_ResetVector)
 
 SECTIONS
 {
-	.start 0xD0000000 : { *(.start) }
-
-	.text 0xD0000000:
-	{
-		__reloc_start = . ;
-		_text_start = . ;
-		*(.literal .text.literal .text)
-		_text_end = . ;
-	}
-
-	.rodata ALIGN(0x04):
-	{
-		*(.rodata)
-		*(.rodata1)
-	}
-
-	.data ALIGN(0x04):
+	.ResetVector.text XCHAL_RESET_VECTOR_VADDR :
 	{
-		*(.data)
-		*(.data1)
-		*(.sdata)
-		*(.sdata2)
-		*(.got.plt)
-		*(.got)
-		*(.dynamic)
+		*(.ResetVector.text)
 	}
 
-	__reloc_end = . ;
-
-	. = ALIGN(0x10);
-	__image_load = . ;
-	.image 0xd0001000:
+	.image KERNELOFFSET: AT (LOAD_MEMORY_ADDRESS)
 	{
 		_image_start = .;
 		*(image)
@@ -43,7 +31,6 @@ SECTIONS
 		_image_end = .	;
 	}
 
-
 	.bss ((LOADADDR(.image) + SIZEOF(.image) + 3) & ~ 3):
 	{
 		__bss_start = .;
@@ -53,14 +40,15 @@ SECTIONS
 		*(.bss)
 		__bss_end = .;
 	}
-	_end = .;
-	_param_start = .;
 
-	.ResetVector.text XCHAL_RESET_VECTOR_VADDR :
+	/*
+	 * This is a remapped copy of the Reset Vector Code.
+	 * It keeps gdb in sync with the PC after switching
+	 * to the temporary mapping used while setting up
+	 * the V2 MMU mappings for Linux.
+	 */
+	.ResetVector.remapped_text 0x46000000 (INFO):
 	{
-		*(.ResetVector.text)
+		*(.ResetVector.remapped_text)
 	}
-
-
-	PROVIDE (end = .);
 }
diff --git a/arch/xtensa/boot/boot-elf/bootstrap.S b/arch/xtensa/boot/boot-elf/bootstrap.S
index 464298bc348..1388a499753 100644
--- a/arch/xtensa/boot/boot-elf/bootstrap.S
+++ b/arch/xtensa/boot/boot-elf/bootstrap.S
@@ -1,18 +1,77 @@
+/*
+ * arch/xtensa/boot/boot-elf/bootstrap.S
+ *
+ * Low-level exception handling
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004 - 2013 by Tensilica Inc.
+ *
+ * Chris Zankel <chris@zankel.net>
+ * Marc Gauthier <marc@tensilica.com>
+ * Piet Delaney <piet@tensilica.com>
+ */
 
 #include <asm/bootparam.h>
+#include <asm/processor.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/cacheasm.h>
+#include <asm/initialize_mmu.h>
+#include <linux/linkage.h>
 
-
-/* ResetVector
- */
-	.section        .ResetVector.text, "ax"
+	.section	.ResetVector.text, "ax"
 	.global         _ResetVector
+	.global         reset
+
 _ResetVector:
-	_j reset
+	_j _SetupMMU
+
+	.begin  no-absolute-literals
+	.literal_position
+
 	.align 4
 RomInitAddr:
-	.word 0xd0001000
+#if defined(CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX) && \
+	XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+	.word 0x00003000
+#else
+	.word 0xd0003000
+#endif
 RomBootParam:
 	.word _bootparam
+_bootparam:
+	.short	BP_TAG_FIRST
+	.short	4
+	.long	BP_VERSION
+	.short	BP_TAG_LAST
+	.short	0
+	.long	0
+
+	.align  4
+_SetupMMU:
+	movi	a0, 0
+	wsr	a0, windowbase
+	rsync
+	movi	a0, 1
+	wsr	a0, windowstart
+	rsync
+	movi	a0, 0x1F
+	wsr	a0, ps
+	rsync
+
+	Offset = _SetupMMU - _ResetVector
+
+#ifndef CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
+	initialize_mmu
+#endif
+
+	.end    no-absolute-literals
+
+	rsil    a0, XCHAL_DEBUGLEVEL-1
+	rsync
 reset:
 	l32r    a0, RomInitAddr
 	l32r	a2, RomBootParam
@@ -21,13 +80,25 @@ reset:
 	jx      a0
 
 	.align 4
-	.section .bootstrap.data, "aw"
 
-	.globl _bootparam
-_bootparam:
-	.short	BP_TAG_FIRST
-	.short	4
-	.long	BP_VERSION
-	.short	BP_TAG_LAST
-	.short	0
-	.long	0
+	.section	.ResetVector.remapped_text, "x"
+	.global         _RemappedResetVector
+
+	/* Do org before literals */
+	.org 0
+
+_RemappedResetVector:
+	.begin  no-absolute-literals
+	.literal_position
+
+	_j	_RemappedSetupMMU
+
+	/* Position Remapped code at the same location as the original code */
+	. = _RemappedResetVector + Offset
+
+_RemappedSetupMMU:
+#ifndef CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
+	initialize_mmu
+#endif
+
+	.end    no-absolute-literals
diff --git a/arch/xtensa/boot/boot-redboot/boot.ld b/arch/xtensa/boot/boot-redboot/boot.ld
index 5bbcaf9e830..b0b9e95b58b 100644
--- a/arch/xtensa/boot/boot-redboot/boot.ld
+++ b/arch/xtensa/boot/boot-redboot/boot.ld
@@ -33,7 +33,7 @@ SECTIONS
 
 	. = ALIGN(0x10);
 	__image_load = . ;
-	.image 0xd0001000: AT(__image_load)
+	.image 0xd0003000: AT(__image_load)
 	{
 		_image_start = .;
 		*(image)
diff --git a/arch/xtensa/boot/boot-uboot/Makefile b/arch/xtensa/boot/boot-uboot/Makefile
index bfbf8af582f..545759819ef 100644
--- a/arch/xtensa/boot/boot-uboot/Makefile
+++ b/arch/xtensa/boot/boot-uboot/Makefile
@@ -4,7 +4,11 @@
 # for more details.
 #
 
-UIMAGE_LOADADDR = 0xd0001000
+ifdef CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
+UIMAGE_LOADADDR = 0x00003000
+else
+UIMAGE_LOADADDR = 0xd0003000
+endif
 UIMAGE_COMPRESSION = gzip
 
 $(obj)/../uImage: vmlinux.bin.gz FORCE
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild
index 095f0a2244f..1b982641ec3 100644
--- a/arch/xtensa/include/asm/Kbuild
+++ b/arch/xtensa/include/asm/Kbuild
@@ -15,6 +15,7 @@ generic-y += irq_regs.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += kvm_para.h
+generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += percpu.h
diff --git a/arch/xtensa/include/asm/ftrace.h b/arch/xtensa/include/asm/ftrace.h
index 40a8c178f10..36dc7a68439 100644
--- a/arch/xtensa/include/asm/ftrace.h
+++ b/arch/xtensa/include/asm/ftrace.h
@@ -1 +1,33 @@
-/* empty */
+/*
+ * arch/xtensa/include/asm/ftrace.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2013 Tensilica Inc.
+ */
+#ifndef _XTENSA_FTRACE_H
+#define _XTENSA_FTRACE_H
+
+#include <asm/processor.h>
+
+#define HAVE_ARCH_CALLER_ADDR
+#define CALLER_ADDR0 ({ unsigned long a0, a1; \
+		__asm__ __volatile__ ( \
+			"mov %0, a0\n" \
+			"mov %1, a1\n" \
+			: "=r"(a0), "=r"(a1) : : ); \
+		MAKE_PC_FROM_RA(a0, a1); })
+#ifdef CONFIG_FRAME_POINTER
+extern unsigned long return_address(unsigned level);
+#define CALLER_ADDR1 return_address(1)
+#define CALLER_ADDR2 return_address(2)
+#define CALLER_ADDR3 return_address(3)
+#else
+#define CALLER_ADDR1 (0)
+#define CALLER_ADDR2 (0)
+#define CALLER_ADDR3 (0)
+#endif
+
+#endif /* _XTENSA_FTRACE_H */
diff --git a/arch/xtensa/include/asm/initialize_mmu.h b/arch/xtensa/include/asm/initialize_mmu.h
index e1f8ba4061e..722553f17db 100644
--- a/arch/xtensa/include/asm/initialize_mmu.h
+++ b/arch/xtensa/include/asm/initialize_mmu.h
@@ -23,6 +23,9 @@
 #ifndef _XTENSA_INITIALIZE_MMU_H
 #define _XTENSA_INITIALIZE_MMU_H
 
+#include <asm/pgtable.h>
+#include <asm/vectors.h>
+
 #ifdef __ASSEMBLY__
 
 #define XTENSA_HWVERSION_RC_2009_0 230000
@@ -48,6 +51,110 @@
 	 * (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0)
 	 */
 
+#if defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+/*
+ * Have MMU v3
+ */
+
+#if !XCHAL_HAVE_VECBASE
+# error "MMU v3 requires reloc vectors"
+#endif
+
+	movi	a1, 0
+	_call0	1f
+	_j	2f
+
+	.align	4
+1:	movi	a2, 0x10000000
+	movi	a3, 0x18000000
+	add	a2, a2, a0
+9:	bgeu	a2, a3, 9b	/* PC is out of the expected range */
+
+	/* Step 1: invalidate mapping at 0x40000000..0x5FFFFFFF. */
+
+	movi	a2, 0x40000006
+	idtlb	a2
+	iitlb	a2
+	isync
+
+	/* Step 2: map 0x40000000..0x47FFFFFF to paddr containing this code
+	 * and jump to the new mapping.
+	 */
+#define CA_BYPASS	(_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+#define CA_WRITEBACK	(_PAGE_CA_WB     | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+
+	srli	a3, a0, 27
+	slli	a3, a3, 27
+	addi	a3, a3, CA_BYPASS
+	addi	a7, a2, -1
+	wdtlb	a3, a7
+	witlb	a3, a7
+	isync
+
+	slli	a4, a0, 5
+	srli	a4, a4, 5
+	addi	a5, a2, -6
+	add	a4, a4, a5
+	jx	a4
+
+	/* Step 3: unmap everything other than current area.
+	 *	   Start at 0x60000000, wrap around, and end with 0x20000000
+	 */
+2:	movi	a4, 0x20000000
+	add	a5, a2, a4
+3:	idtlb	a5
+	iitlb	a5
+	add	a5, a5, a4
+	bne	a5, a2, 3b
+
+	/* Step 4: Setup MMU with the old V2 mappings. */
+	movi	a6, 0x01000000
+	wsr	a6, ITLBCFG
+	wsr	a6, DTLBCFG
+	isync
+
+	movi	a5, 0xd0000005
+	movi	a4, CA_WRITEBACK
+	wdtlb	a4, a5
+	witlb	a4, a5
+
+	movi	a5, 0xd8000005
+	movi	a4, CA_BYPASS
+	wdtlb	a4, a5
+	witlb	a4, a5
+
+	movi	a5, 0xe0000006
+	movi	a4, 0xf0000000 + CA_WRITEBACK
+	wdtlb	a4, a5
+	witlb	a4, a5
+
+	movi	a5, 0xf0000006
+	movi	a4, 0xf0000000 + CA_BYPASS
+	wdtlb	a4, a5
+	witlb	a4, a5
+
+	isync
+
+	/* Jump to self, using MMU v2 mappings. */
+	movi	a4, 1f
+	jx	a4
+
+1:
+	movi    a2, VECBASE_RESET_VADDR
+	wsr	a2, vecbase
+
+	/* Step 5: remove temporary mapping. */
+	idtlb	a7
+	iitlb	a7
+	isync
+
+	movi	a0, 0
+	wsr	a0, ptevaddr
+	rsync
+
+#endif /* defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU &&
+	  XCHAL_HAVE_SPANNING_WAY */
+
 	.endm
 
 #endif /*__ASSEMBLY__*/
diff --git a/arch/xtensa/include/asm/irqflags.h b/arch/xtensa/include/asm/irqflags.h
index f865b1c1eae..ea36674c6ec 100644
--- a/arch/xtensa/include/asm/irqflags.h
+++ b/arch/xtensa/include/asm/irqflags.h
@@ -47,7 +47,10 @@ static inline void arch_local_irq_restore(unsigned long flags)
 
 static inline bool arch_irqs_disabled_flags(unsigned long flags)
 {
-	return (flags & 0xf) != 0;
+#if XCHAL_EXCM_LEVEL < LOCKLEVEL || (1 << PS_EXCM_BIT) < LOCKLEVEL
+#error "XCHAL_EXCM_LEVEL and 1<<PS_EXCM_BIT must be no less than LOCKLEVEL"
+#endif
+	return (flags & (PS_INTLEVEL_MASK | (1 << PS_EXCM_BIT))) >= LOCKLEVEL;
 }
 
 static inline bool arch_irqs_disabled(void)
diff --git a/arch/xtensa/include/asm/linkage.h b/arch/xtensa/include/asm/linkage.h
deleted file mode 100644
index bf2128a99d7..00000000000
--- a/arch/xtensa/include/asm/linkage.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * include/asm-xtensa/linkage.h
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2001 - 2005 Tensilica Inc.
- */
-
-#ifndef _XTENSA_LINKAGE_H
-#define _XTENSA_LINKAGE_H
-
-/* Nothing to do here ... */
-
-#endif	/* _XTENSA_LINKAGE_H */
diff --git a/arch/xtensa/include/asm/stacktrace.h b/arch/xtensa/include/asm/stacktrace.h
new file mode 100644
index 00000000000..6a05fcb0a20
--- /dev/null
+++ b/arch/xtensa/include/asm/stacktrace.h
@@ -0,0 +1,36 @@
+/*
+ * arch/xtensa/include/asm/stacktrace.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2013 Tensilica Inc.
+ */
+#ifndef _XTENSA_STACKTRACE_H
+#define _XTENSA_STACKTRACE_H
+
+#include <linux/sched.h>
+
+struct stackframe {
+	unsigned long pc;
+	unsigned long sp;
+};
+
+static __always_inline unsigned long *stack_pointer(struct task_struct *task)
+{
+	unsigned long *sp;
+
+	if (!task || task == current)
+		__asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp));
+	else
+		sp = (unsigned long *)task->thread.sp;
+
+	return sp;
+}
+
+void walk_stackframe(unsigned long *sp,
+		int (*fn)(struct stackframe *frame, void *data),
+		void *data);
+
+#endif /* _XTENSA_STACKTRACE_H */
diff --git a/arch/xtensa/include/asm/timex.h b/arch/xtensa/include/asm/timex.h
index 9e85ce8bd8d..3d35e5d0367 100644
--- a/arch/xtensa/include/asm/timex.h
+++ b/arch/xtensa/include/asm/timex.h
@@ -19,13 +19,16 @@
 #define _INTLEVEL(x)	XCHAL_INT ## x ## _LEVEL
 #define INTLEVEL(x)	_INTLEVEL(x)
 
-#if INTLEVEL(XCHAL_TIMER0_INTERRUPT) <= XCHAL_EXCM_LEVEL
+#if XCHAL_NUM_TIMERS > 0 && \
+	INTLEVEL(XCHAL_TIMER0_INTERRUPT) <= XCHAL_EXCM_LEVEL
 # define LINUX_TIMER     0
 # define LINUX_TIMER_INT XCHAL_TIMER0_INTERRUPT
-#elif INTLEVEL(XCHAL_TIMER1_INTERRUPT) <= XCHAL_EXCM_LEVEL
+#elif XCHAL_NUM_TIMERS > 1 && \
+	INTLEVEL(XCHAL_TIMER1_INTERRUPT) <= XCHAL_EXCM_LEVEL
 # define LINUX_TIMER     1
 # define LINUX_TIMER_INT XCHAL_TIMER1_INTERRUPT
-#elif INTLEVEL(XCHAL_TIMER2_INTERRUPT) <= XCHAL_EXCM_LEVEL
+#elif XCHAL_NUM_TIMERS > 2 && \
+	INTLEVEL(XCHAL_TIMER2_INTERRUPT) <= XCHAL_EXCM_LEVEL
 # define LINUX_TIMER     2
 # define LINUX_TIMER_INT XCHAL_TIMER2_INTERRUPT
 #else
diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h
index b5464ef3cf6..917488a0ab0 100644
--- a/arch/xtensa/include/asm/traps.h
+++ b/arch/xtensa/include/asm/traps.h
@@ -22,10 +22,9 @@ extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
 
 static inline void spill_registers(void)
 {
-	unsigned int a0, ps;
 
 	__asm__ __volatile__ (
-		"movi	a14, " __stringify(PS_EXCM_BIT | LOCKLEVEL) "\n\t"
+		"movi	a14, "__stringify((1 << PS_EXCM_BIT) | LOCKLEVEL)"\n\t"
 		"mov	a12, a0\n\t"
 		"rsr	a13, sar\n\t"
 		"xsr	a14, ps\n\t"
@@ -35,7 +34,7 @@ static inline void spill_registers(void)
 		"mov	a0, a12\n\t"
 		"wsr	a13, sar\n\t"
 		"wsr	a14, ps\n\t"
-		: : "a" (&a0), "a" (&ps)
+		: :
 #if defined(CONFIG_FRAME_POINTER)
 		: "a2", "a3", "a4",       "a11", "a12", "a13", "a14", "a15",
 #else
diff --git a/arch/xtensa/include/asm/vectors.h b/arch/xtensa/include/asm/vectors.h
new file mode 100644
index 00000000000..c52b656d031
--- /dev/null
+++ b/arch/xtensa/include/asm/vectors.h
@@ -0,0 +1,125 @@
+/*
+ * arch/xtensa/include/asm/xchal_vaddr_remap.h
+ *
+ * Xtensa macros for MMU V3 Support. Deals with re-mapping the Virtual
+ * Memory Addresses from "Virtual == Physical" to their prevvious V2 MMU
+ * mappings (KSEG at 0xD0000000 and KIO at 0XF0000000).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2008 - 2012 Tensilica Inc.
+ *
+ * Pete Delaney <piet@tensilica.com>
+ * Marc Gauthier <marc@tensilica.com
+ */
+
+#ifndef _XTENSA_VECTORS_H
+#define _XTENSA_VECTORS_H
+
+#include <variant/core.h>
+
+#if defined(CONFIG_MMU)
+
+/* Will Become VECBASE */
+#define VIRTUAL_MEMORY_ADDRESS		0xD0000000
+
+/* Image Virtual Start Address */
+#define KERNELOFFSET			0xD0003000
+
+#if defined(XCHAL_HAVE_PTP_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+  /* MMU v3  - XCHAL_HAVE_PTP_MMU  == 1 */
+  #define PHYSICAL_MEMORY_ADDRESS	0x00000000
+  #define LOAD_MEMORY_ADDRESS		0x00003000
+#else
+  /* MMU V2 -  XCHAL_HAVE_PTP_MMU  == 0 */
+  #define PHYSICAL_MEMORY_ADDRESS	0xD0000000
+  #define LOAD_MEMORY_ADDRESS		0xD0003000
+#endif
+
+#else /* !defined(CONFIG_MMU) */
+  /* MMU Not being used - Virtual == Physical */
+
+  /* VECBASE */
+  #define VIRTUAL_MEMORY_ADDRESS	0x00002000
+
+  /* Location of the start of the kernel text, _start */
+  #define KERNELOFFSET			0x00003000
+  #define PHYSICAL_MEMORY_ADDRESS	0x00000000
+
+  /* Loaded just above possibly live vectors */
+  #define LOAD_MEMORY_ADDRESS		0x00003000
+
+#endif /* CONFIG_MMU */
+
+#define XC_VADDR(offset)		(VIRTUAL_MEMORY_ADDRESS  + offset)
+#define XC_PADDR(offset)		(PHYSICAL_MEMORY_ADDRESS + offset)
+
+/* Used to set VECBASE register */
+#define VECBASE_RESET_VADDR		VIRTUAL_MEMORY_ADDRESS
+
+#define RESET_VECTOR_VECOFS		(XCHAL_RESET_VECTOR_VADDR - \
+						VECBASE_RESET_VADDR)
+#define RESET_VECTOR_VADDR		XC_VADDR(RESET_VECTOR_VECOFS)
+
+#define RESET_VECTOR1_VECOFS		(XCHAL_RESET_VECTOR1_VADDR - \
+						VECBASE_RESET_VADDR)
+#define RESET_VECTOR1_VADDR		XC_VADDR(RESET_VECTOR1_VECOFS)
+
+#if XCHAL_HAVE_VECBASE
+
+#define USER_VECTOR_VADDR		XC_VADDR(XCHAL_USER_VECOFS)
+#define KERNEL_VECTOR_VADDR		XC_VADDR(XCHAL_KERNEL_VECOFS)
+#define DOUBLEEXC_VECTOR_VADDR		XC_VADDR(XCHAL_DOUBLEEXC_VECOFS)
+#define WINDOW_VECTORS_VADDR		XC_VADDR(XCHAL_WINDOW_OF4_VECOFS)
+#define INTLEVEL2_VECTOR_VADDR		XC_VADDR(XCHAL_INTLEVEL2_VECOFS)
+#define INTLEVEL3_VECTOR_VADDR		XC_VADDR(XCHAL_INTLEVEL3_VECOFS)
+#define INTLEVEL4_VECTOR_VADDR		XC_VADDR(XCHAL_INTLEVEL4_VECOFS)
+#define INTLEVEL5_VECTOR_VADDR		XC_VADDR(XCHAL_INTLEVEL5_VECOFS)
+#define INTLEVEL6_VECTOR_VADDR		XC_VADDR(XCHAL_INTLEVEL6_VECOFS)
+
+#define DEBUG_VECTOR_VADDR		XC_VADDR(XCHAL_DEBUG_VECOFS)
+
+#undef  XCHAL_NMI_VECTOR_VADDR
+#define XCHAL_NMI_VECTOR_VADDR		XC_VADDR(XCHAL_NMI_VECOFS)
+
+#undef  XCHAL_INTLEVEL7_VECTOR_VADDR
+#define XCHAL_INTLEVEL7_VECTOR_VADDR	XC_VADDR(XCHAL_INTLEVEL7_VECOFS)
+
+/*
+ * These XCHAL_* #defines from varian/core.h
+ * are not valid to use with V3 MMU. Non-XCHAL
+ * constants are defined above and should be used.
+ */
+#undef  XCHAL_VECBASE_RESET_VADDR
+#undef  XCHAL_RESET_VECTOR0_VADDR
+#undef  XCHAL_USER_VECTOR_VADDR
+#undef  XCHAL_KERNEL_VECTOR_VADDR
+#undef  XCHAL_DOUBLEEXC_VECTOR_VADDR
+#undef  XCHAL_WINDOW_VECTORS_VADDR
+#undef  XCHAL_INTLEVEL2_VECTOR_VADDR
+#undef  XCHAL_INTLEVEL3_VECTOR_VADDR
+#undef  XCHAL_INTLEVEL4_VECTOR_VADDR
+#undef  XCHAL_INTLEVEL5_VECTOR_VADDR
+#undef  XCHAL_INTLEVEL6_VECTOR_VADDR
+#undef  XCHAL_DEBUG_VECTOR_VADDR
+#undef  XCHAL_NMI_VECTOR_VADDR
+#undef  XCHAL_INTLEVEL7_VECTOR_VADDR
+
+#else
+
+#define USER_VECTOR_VADDR		XCHAL_USER_VECTOR_VADDR
+#define KERNEL_VECTOR_VADDR		XCHAL_KERNEL_VECTOR_VADDR
+#define DOUBLEEXC_VECTOR_VADDR		XCHAL_DOUBLEEXC_VECTOR_VADDR
+#define WINDOW_VECTORS_VADDR		XCHAL_WINDOW_VECTORS_VADDR
+#define INTLEVEL2_VECTOR_VADDR		XCHAL_INTLEVEL2_VECTOR_VADDR
+#define INTLEVEL3_VECTOR_VADDR		XCHAL_INTLEVEL3_VECTOR_VADDR
+#define INTLEVEL4_VECTOR_VADDR		XCHAL_INTLEVEL4_VECTOR_VADDR
+#define INTLEVEL5_VECTOR_VADDR		XCHAL_INTLEVEL5_VECTOR_VADDR
+#define INTLEVEL6_VECTOR_VADDR		XCHAL_INTLEVEL6_VECTOR_VADDR
+#define DEBUG_VECTOR_VADDR		XCHAL_DEBUG_VECTOR_VADDR
+
+#endif
+
+#endif /* _XTENSA_VECTORS_H */
diff --git a/arch/xtensa/kernel/Makefile b/arch/xtensa/kernel/Makefile
index c3a59d992ac..1e7fc87a94b 100644
--- a/arch/xtensa/kernel/Makefile
+++ b/arch/xtensa/kernel/Makefile
@@ -4,14 +4,16 @@
 
 extra-y := head.o vmlinux.lds
 
-obj-y := align.o entry.o irq.o coprocessor.o process.o ptrace.o \
-	 setup.o signal.o syscall.o time.o traps.o vectors.o platform.o  \
-	 pci-dma.o
+obj-y := align.o coprocessor.o entry.o irq.o pci-dma.o platform.o process.o \
+	 ptrace.o setup.o signal.o stacktrace.o syscall.o time.o traps.o \
+	 vectors.o
 
 obj-$(CONFIG_KGDB) += xtensa-stub.o
 obj-$(CONFIG_PCI) += pci.o
 obj-$(CONFIG_MODULES) += xtensa_ksyms.o module.o
 
+AFLAGS_head.o += -mtext-section-literals
+
 # In the Xtensa architecture, assembly generates literals which must always
 # precede the L32R instruction with a relative offset less than 256 kB.
 # Therefore, the .text and .literal section must be combined in parenthesis
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 63845f95079..5082507d563 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -354,16 +354,16 @@ common_exception:
 	 * so we can allow exceptions and interrupts (*) again.
 	 * Set PS(EXCM = 0, UM = 0, RING = 0, OWB = 0, WOE = 1, INTLEVEL = X)
 	 *
-	 * (*) We only allow interrupts of higher priority than current IRQ
+	 * (*) We only allow interrupts if they were previously enabled and
+	 *     we're not handling an IRQ
 	 */
 
 	rsr	a3, ps
-	addi	a0, a0, -4
-	movi	a2, 1
+	addi	a0, a0, -EXCCAUSE_LEVEL1_INTERRUPT
+	movi	a2, LOCKLEVEL
 	extui	a3, a3, PS_INTLEVEL_SHIFT, PS_INTL