Blackfin arch: add an option to allow people to stick exception stack into L1 scratch

allow people to stick exception stack into L1 scratch
and make sure it gets placed into .bss sections rather than .data

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

1 files changed, 15 insertions, 6 deletions

diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index bde6dc4e2614..ad4049882291 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -1539,14 +1539,23 @@ ENTRY(_sys_call_table)
         .endr
 END(_sys_call_table)
 
-_exception_stack:
-        .rept 1024
-        .long 0;
-        .endr
-_exception_stack_top:
-
 #if ANOMALY_05000261
 /* Used by the assembly entry point to work around an anomaly.  */
 _last_cplb_fault_retx:
         .long 0;
 #endif
+
+#ifdef CONFIG_EXCEPTION_L1_SCRATCH
+/* .section .l1.bss.scratch */
+.set _exception_stack_top, L1_SCRATCH_START + L1_SCRATCH_LENGTH
+#else
+#ifdef CONFIG_SYSCALL_TAB_L1
+.section .l1.bss
+#else
+.bss
+#endif
+_exception_stack:
+.size _exception_stack, 1024 * 4
+.set _exception_stack_top, _exception_stack + 1024 * 4
+.size _exception_stack_top, 0
+#endif