ARM: 8035/1: Disable preemption in crunch_task_enable()

This patch is in preparation for calling the crunch_task_enable()
function with interrupts enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/arm/mach-ep93xx/crunch-bits.S b/arch/arm/mach-ep93xx/crunch-bits.S
index 0ec9bb48fab9..eaa5e34729d3 100644
--- a/arch/arm/mach-ep93xx/crunch-bits.S
+++ b/arch/arm/mach-ep93xx/crunch-bits.S
@@ -16,6 +16,7 @@
 #include <asm/ptrace.h>
 #include <asm/thread_info.h>
 #include <asm/asm-offsets.h>
+#include <asm/assembler.h>
 #include <mach/ep93xx-regs.h>
 
 /*
@@ -65,11 +66,13 @@
  * called from prefetch exception handler with interrupts disabled
  */
 ENTRY(crunch_task_enable)
+        inc_preempt_count r10, r3
+
         ldr     r8, =(EP93XX_APB_VIRT_BASE + 0x00130000)        @ syscon addr
 
         ldr     r1, [r8, #0x80]
         tst     r1, #0x00800000                 @ access to crunch enabled?
-        movne   pc, lr                          @ if so no business here
+        bne     2f                              @ if so no business here
         mov     r3, #0xaa                       @ unlock syscon swlock
         str     r3, [r8, #0xc0]
         orr     r1, r1, #0x00800000             @ enable access to crunch
@@ -142,7 +145,7 @@ crunch_save:
 
         teq             r0, #0                          @ anything to load?
         cfldr64eq       mvdx0, [r1, #CRUNCH_MVDX0]      @ mvdx0 was clobbered
-        moveq           pc, lr
+        beq             1f
 
 crunch_load:
         cfldr64         mvdx0, [r0, #CRUNCH_DSPSC]      @ load status word
@@ -190,6 +193,11 @@ crunch_load:
         cfldr64         mvdx14, [r0, #CRUNCH_MVDX14]
         cfldr64         mvdx15, [r0, #CRUNCH_MVDX15]
 
+1:
+#ifdef CONFIG_PREEMPT_COUNT
+        get_thread_info r10
+#endif
+2:      dec_preempt_count r10, r3
         mov     pc, lr
 
 /*