5 files changed, 238 insertions, 142 deletions

diff --git a/arch/xtensa/include/asm/regs.h b/arch/xtensa/include/asm/regs.h
index b24de6717020..4ba9f516b0e2 100644
--- a/arch/xtensa/include/asm/regs.h
+++ b/arch/xtensa/include/asm/regs.h
@@ -82,6 +82,7 @@
 #define PS_CALLINC_SHIFT        16
 #define PS_CALLINC_MASK         0x00030000
 #define PS_OWB_SHIFT            8
+#define PS_OWB_WIDTH            4
 #define PS_OWB_MASK             0x00000F00
 #define PS_RING_SHIFT           6
 #define PS_RING_MASK            0x000000C0
diff --git a/arch/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S
index aa2e87b8566a..d4cef6039a5c 100644
--- a/arch/xtensa/kernel/align.S
+++ b/arch/xtensa/kernel/align.S
@@ -146,9 +146,9 @@
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original in DEPC
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave_1: a3
+ *   excsave_1: dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -171,7 +171,6 @@ ENTRY(fast_unaligned)
         s32i    a8, a2, PT_AREG8
 
         rsr     a0, depc
-        xsr     a3, excsave1
         s32i    a0, a2, PT_AREG2
         s32i    a3, a2, PT_AREG3
 
diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
index 647657484866..a482df5df2b2 100644
--- a/arch/xtensa/kernel/coprocessor.S
+++ b/arch/xtensa/kernel/coprocessor.S
@@ -32,9 +32,9 @@
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original in DEPC
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave_1: a3
+ *   excsave_1: dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -225,9 +225,9 @@ ENDPROC(coprocessor_restore)
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original in DEPC
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave_1: a3
+ *   excsave_1: dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -245,7 +245,6 @@ ENTRY(fast_coprocessor)
 
         /* Save remaining registers a1-a3 and SAR */
 
-        xsr     a3, excsave1
         s32i    a3, a2, PT_AREG3
         rsr     a3, sar
         s32i    a1, a2, PT_AREG1
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 3f3de283d707..ab025c1f6e23 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -91,9 +91,9 @@
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original value in depc
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave1:  a3
+ *   excsave1:  dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -109,9 +109,8 @@
 
 ENTRY(user_exception)
 
-        /* Save a2, a3, and depc, restore excsave_1 and set SP. */
+        /* Save a1, a2, a3, and set SP. */
 
-        xsr     a3, excsave1
         rsr     a0, depc
         s32i    a1, a2, PT_AREG1
         s32i    a0, a2, PT_AREG2
@@ -237,9 +236,9 @@ ENDPROC(user_exception)
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original in DEPC
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave_1: a3
+ *   excsave_1: dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -255,9 +254,8 @@ ENDPROC(user_exception)
 
 ENTRY(kernel_exception)
 
-        /* Save a0, a2, a3, DEPC and set SP. */
+        /* Save a1, a2, a3, and set SP. */
 
-        xsr     a3, excsave1            # restore a3, excsave_1
         rsr     a0, depc                # get a2
         s32i    a1, a2, PT_AREG1
         s32i    a0, a2, PT_AREG2
@@ -408,7 +406,7 @@ common_exception:
          * exception handler and call the exception handler.
          */
 
-        movi    a4, exc_table
+        rsr     a4, excsave1
         mov     a6, a1                  # pass stack frame
         mov     a7, a0                  # pass EXCCAUSE
         addx4   a4, a0, a4
@@ -832,9 +830,9 @@ ENDPROC(unrecoverable_exception)
  *   a0:        trashed, original value saved on stack (PT_AREG0)
  *   a1:        a1
  *   a2:        new stack pointer, original in DEPC
- *   a3:        dispatch table
+ *   a3:        a3
  *   depc:      a2, original value saved on stack (PT_DEPC)
- *   excsave_1: a3
+ *   excsave_1: dispatch table
  *
  *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
  *           <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
@@ -857,18 +855,16 @@ ENTRY(fast_alloca)
 
         rsr     a0, depc                # get a2
         s32i    a4, a2, PT_AREG4        # save a4 and
+        s32i    a3, a2, PT_AREG3
         s32i    a0, a2, PT_AREG2        # a2 to stack
 
         /* Exit critical section. */
 
         movi    a0, 0
+        rsr     a3, excsave1
         s32i    a0, a3, EXC_TABLE_FIXUP
 
-        /* Restore a3, excsave_1 */
-
-        xsr     a3, excsave1            # make sure excsave_1 is valid for dbl.
         rsr     a4, epc1                # get exception address