Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

Pull ARM updates from Russell King:

 - UEFI boot and runtime services support for ARM from Ard Biesheuvel
   and Roy Franz.

 - DT compatibility with old atags booting protocol for Nokia N900
   devices from Ivaylo Dimitrov.

 - PSCI firmware interface using new arm-smc calling convention from
   Jens Wiklander.

 - Runtime patching for udiv/sdiv instructions for ARMv7 CPUs that
   support these instructions from Nicolas Pitre.

 - L2x0 cache updates from Dirk B and Linus Walleij.

 - Randconfig fixes from Arnd Bergmann.

 - ARMv7M (nommu) updates from Ezequiel Garcia

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (34 commits)
  ARM: 8481/2: drivers: psci: replace psci firmware calls
  ARM: 8480/2: arm64: add implementation for arm-smccc
  ARM: 8479/2: add implementation for arm-smccc
  ARM: 8478/2: arm/arm64: add arm-smccc
  ARM: 8494/1: mm: Enable PXN when running non-LPAE kernel on LPAE processor
  ARM: 8496/1: OMAP: RX51: save ATAGS data in the early boot stage
  ARM: 8495/1: ATAGS: move save_atags() to arch/arm/include/asm/setup.h
  ARM: 8452/3: PJ4: make coprocessor access sequences buildable in Thumb2 mode
  ARM: 8482/1: l2x0: make it possible to disable outer sync from DT
  ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI
  ARM: 8487/1: Remove IPI_CALL_FUNC_SINGLE
  ARM: 8485/1: cpuidle: remove cpu parameter from the cpuidle_ops suspend hook
  ARM: 8484/1: Documentation: l2c2x0: Mention separate controllers explicitly
  ARM: 8483/1: Documentation: l2c: Rename l2cc to l2c2x0
  ARM: 8477/1: runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()
  ARM: 8476/1: VDSO: use PTR_ERR_OR_ZERO for vma check
  ARM: 8453/2: proc-v7.S: don't locate temporary stack space in .text section
  ARM: add UEFI stub support
  ARM: wire up UEFI init and runtime support
  ARM: only consider memblocks with NOMAP cleared for linear mapping
  ...

1 files changed, 5 insertions, 9 deletions

diff --git a/arch/arm/mm/proc-v7m.S b/arch/arm/mm/proc-v7m.S
index 67d9209077c6..7229d8d0be1a 100644
--- a/arch/arm/mm/proc-v7m.S
+++ b/arch/arm/mm/proc-v7m.S
@@ -12,6 +12,7 @@
  */
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/memory.h>
 #include <asm/v7m.h>
 #include "proc-macros.S"
 
@@ -97,19 +98,19 @@ __v7m_setup:
 	mov	r5, #0x00800000
 	str	r5, [r0, V7M_SCB_SHPR3]	@ set PendSV priority
 
-	@ SVC to run the kernel in this mode
+	@ SVC to switch to handler mode. Notice that this requires sp to
+	@ point to writeable memory because the processor saves
+	@ some registers to the stack.
 	badr	r1, 1f
 	ldr	r5, [r12, #11 * 4]	@ read the SVC vector entry
 	str	r1, [r12, #11 * 4]	@ write the temporary SVC vector entry
 	mov	r6, lr			@ save LR
-	mov	r7, sp			@ save SP
-	ldr	sp, =__v7m_setup_stack_top
+	ldr	sp, =init_thread_union + THREAD_START_SP
 	cpsie	i
 	svc	#0
 1:	cpsid	i
 	str	r5, [r12, #11 * 4]	@ restore the original SVC vector entry
 	mov	lr, r6			@ restore LR
-	mov	sp, r7			@ restore SP
 
 	@ Special-purpose control register
 	mov	r1, #1
@@ -123,11 +124,6 @@ __v7m_setup:
 	ret	lr
 ENDPROC(__v7m_setup)
 
-	.align 2
-__v7m_setup_stack:
-	.space	4 * 8				@ 8 registers
-__v7m_setup_stack_top:
-
 	define_processor_functions v7m, dabort=nommu_early_abort, pabort=legacy_pabort, nommu=1
 
 	.section ".rodata"