3 files changed, 40 insertions, 98 deletions

diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index d0f675422074..5b847070dae5 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -67,6 +67,8 @@ void __init trap_init(void)
         CSYNC();
 }
 
+void *saved_icplb_fault_addr, *saved_dcplb_fault_addr;
+
 int kstack_depth_to_print = 48;
 
 static void decode_address(char *buf, unsigned long address)
@@ -703,10 +705,7 @@ void dump_bfin_mem(struct pt_regs *fp)
         unsigned short *addr, *erraddr, val = 0, err = 0;
         char sti = 0, buf[6];
 
-        if (unlikely((fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR))
-                erraddr = (void *)fp->pc;
-        else
-                erraddr = (void *)fp->retx;
+        erraddr = (void *)fp->pc;
 
         printk(KERN_NOTICE "return address: [0x%p]; contents of:", erraddr);
 
@@ -830,9 +829,9 @@ unlock:
 
         if (((long)fp->seqstat &  SEQSTAT_EXCAUSE) &&
             (((long)fp->seqstat & SEQSTAT_EXCAUSE) != VEC_HWERR)) {
-                decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
+                decode_address(buf, saved_dcplb_fault_addr);
                 printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
-                decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
+                decode_address(buf, saved_icplb_fault_addr);
                 printk(KERN_NOTICE "ICPLB_FAULT_ADDR: %s\n", buf);
         }
 
@@ -940,8 +939,8 @@ void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
 
         oops_in_progress = 1;
 
-        printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
-        printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
+        printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", saved_dcplb_fault_addr);
+        printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", saved_icplb_fault_addr);
         dump_bfin_process(fp);
         dump_bfin_mem(fp);
         show_regs(fp);
diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index a504c65d9990..f2fb87e9a46e 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -38,6 +38,7 @@
 #include <linux/unistd.h>
 #include <asm/blackfin.h>
 #include <asm/errno.h>
+#include <asm/fixed_code.h>
 #include <asm/thread_info.h>  /* TIF_NEED_RESCHED */
 #include <asm/asm-offsets.h>
 #include <asm/trace.h>
@@ -52,15 +53,6 @@
 # define EX_SCRATCH_REG CYCLES
 #endif
 
-#if ANOMALY_05000281
-ENTRY(_safe_speculative_execution)
-        NOP;
-        NOP;
-        NOP;
-        jump _safe_speculative_execution;
-ENDPROC(_safe_speculative_execution)
-#endif
-
 #ifdef CONFIG_EXCPT_IRQ_SYSC_L1
 .section .l1.text
 #else
@@ -230,6 +222,26 @@ ENTRY(_ex_trap_c)
         [p4] = p5;
         csync;
 
+        p4.l = lo(DCPLB_FAULT_ADDR);
+        p4.h = hi(DCPLB_FAULT_ADDR);
+        r7 = [p4];
+        p5.h = _saved_dcplb_fault_addr;
+        p5.l = _saved_dcplb_fault_addr;
+        [p5] = r7;
+
+        r7 = [p4 + (ICPLB_FAULT_ADDR - DCPLB_FAULT_ADDR)];
+        p5.h = _saved_icplb_fault_addr;
+        p5.l = _saved_icplb_fault_addr;
+        [p5] = r7;
+
+        p4.l = __retx;
+        p4.h = __retx;
+        r6 = retx;
+        [p4] = r6;
+        p4.l = lo(SAFE_USER_INSTRUCTION);
+        p4.h = hi(SAFE_USER_INSTRUCTION);
+        retx = p4;
+
         /* Disable all interrupts, but make sure level 5 is enabled so
          * we can switch to that level.  Save the old mask.  */
         cli r6;
@@ -239,23 +251,6 @@ ENTRY(_ex_trap_c)
         r6 = 0x3f;
         sti r6;
 
-        /* Save the excause into a circular buffer, in case the instruction
-         * which caused this excecptions causes others.
-         */
-        P5.l = _in_ptr_excause;
-        P5.h = _in_ptr_excause;
-        R7 = [P5];
-        R7 += 4;
-        R6 = 0xF;
-        R7 = R7 & R6;
-        [P5] = R7;
-        R6.l = _excause_circ_buf;
-        R6.h = _excause_circ_buf;
-        R7 = R7 + R6;
-        p5 = R7;
-        R6 = SEQSTAT;
-        [P5] = R6;
-
         (R7:6,P5:4) = [sp++];
         ASTAT = [sp++];
         SP = EX_SCRATCH_REG;
@@ -312,6 +307,11 @@ ENDPROC(_double_fault)
 ENTRY(_exception_to_level5)
         SAVE_ALL_SYS
 
+        p4.l = __retx;
+        p4.h = __retx;
+        r6 = [p4];
+        [sp + PT_PC] = r6;
+
         /* Restore interrupt mask.  We haven't pushed RETI, so this
          * doesn't enable interrupts until we return from this handler.  */
         p4.l = _excpt_saved_imask;
@@ -333,42 +333,11 @@ ENTRY(_exception_to_level5)
         r0 = [p2];              /* Read current IPEND */
         [sp + PT_IPEND] = r0;   /* Store IPEND */
 
-        /* Pop the excause from the circular buffer and push it on the stack
-         * (in the right place - if you change the location of SEQSTAT, you
-         * must change this offset.
-         */
-.L_excep_to_5_again:
-        P5.l = _out_ptr_excause;
-        P5.h = _out_ptr_excause;
-        R7 = [P5];
-        R7 += 4;
-        R6 = 0xF;
-        R7 = R7 & R6;
-        [P5] = R7;
-        R6.l = _excause_circ_buf;
-        R6.h = _excause_circ_buf;
-        R7 = R7 + R6;
-        P5 = R7;
-        R1 = [P5];
-        [SP + PT_SEQSTAT] = r1;
-
         r0 = sp;        /* stack frame pt_regs pointer argument ==> r0 */
         SP += -12;
         call _trap_c;
         SP += 12;
 
-        /* See if anything else is in the exception buffer
-         * if there is, process it
-         */
-        P5.l = _out_ptr_excause;
-        P5.h = _out_ptr_excause;
-        P4.l = _in_ptr_excause;
-        P4.h = _in_ptr_excause;
-        R6 = [P5];
-        R7 = [P4];
-        CC = R6 == R7;
-        if ! CC JUMP .L_excep_to_5_again
-
         call _ret_from_exception;
         RESTORE_ALL_SYS
         rti;
@@ -732,8 +701,8 @@ ENTRY(_return_from_int)
         [p0] = p1;
         csync;
 #if ANOMALY_05000281
-        r0.l = _safe_speculative_execution;
-        r0.h = _safe_speculative_execution;
+        r0.l = lo(SAFE_USER_INSTRUCTION);
+        r0.h = hi(SAFE_USER_INSTRUCTION);
         reti = r0;
 #endif
         r0 = 0x801f (z);
@@ -746,8 +715,8 @@ ENDPROC(_return_from_int)
 
 ENTRY(_lower_to_irq14)
 #if ANOMALY_05000281
-        r0.l = _safe_speculative_execution;
-        r0.h = _safe_speculative_execution;
+        r0.l = lo(SAFE_USER_INSTRUCTION);
+        r0.h = hi(SAFE_USER_INSTRUCTION);
         reti = r0;
 #endif
         r0 = 0x401f;
@@ -814,20 +783,6 @@ _schedule_and_signal:
         rti;
 ENDPROC(_lower_to_irq14)
 
-/* Make sure when we start, that the circular buffer is initialized properly
- * R0 and P0 are call clobbered, so we can use them here.
- */
-ENTRY(_init_exception_buff)
-        r0 = 0;
-        p0.h = _in_ptr_excause;
-        p0.l = _in_ptr_excause;
-        [p0] = r0;
-        p0.h = _out_ptr_excause;
-        p0.l = _out_ptr_excause;
-        [p0] = r0;
-        rts;
-ENDPROC(_init_exception_buff)
-
 /* We handle this 100% in exception space - to reduce overhead
  * Only potiential problem is if the software buffer gets swapped out of the
  * CPLB table - then double fault. - so we don't let this happen in other places
@@ -1403,17 +1358,7 @@ _exception_stack_top:
 _last_cplb_fault_retx:
         .long 0;
 #endif
-/*
- * Single instructions can have multiple faults, which need to be
- * handled by traps.c, in irq5. We store the exception cause to ensure
- * we don't miss a double fault condition
- */
-ENTRY(_in_ptr_excause)
-        .long 0;
-ENTRY(_out_ptr_excause)
+        /* Used to save the real RETX when temporarily storing a safe
+         * return address.  */
+__retx:
         .long 0;
-ALIGN
-ENTRY(_excause_circ_buf)
-        .rept 4
-        .long 0
-        .endr
diff --git a/arch/blackfin/mach-common/ints-priority.c b/arch/blackfin/mach-common/ints-priority.c
index 5448230c0e95..f5fd768022ea 100644
--- a/arch/blackfin/mach-common/ints-priority.c
+++ b/arch/blackfin/mach-common/ints-priority.c
@@ -939,8 +939,6 @@ int __init init_arch_irq(void)
 
         local_irq_disable();
 
-        init_exception_buff();
-
 #ifdef CONFIG_BF54x
 # ifdef CONFIG_PINTx_REASSIGN
         pint[0]->assign = CONFIG_PINT0_ASSIGN;