Blackfin: keep hwtrace on CPLB miss

Crashes rarely happen in the CPLB miss handler compared to the rest of
U-Boot code, so disable hardware tracing when processing misses.  This
way a crash due to other functions will be shown properly.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/cpu/blackfin/traps.c b/cpu/blackfin/traps.c
index 7e7c74ce4736bf8707a0f463cf3bb63d0ae60bad..becc36e6a99cbb186cf6c1bcadac02d4bc7dd03a 100644 (file)
--- a/cpu/blackfin/traps.c
+++ b/cpu/blackfin/traps.c
@@ -100,6 +100,14 @@ void trap_c(struct pt_regs *regs)
                uint32_t new_cplb_addr = 0, new_cplb_data = 0;
                static size_t last_evicted;
                size_t i;
+               unsigned long tflags;
+
+               /*
+                * Keep the trace buffer so that a miss here points people
+                * to the right place (their code).  Crashes here rarely
+                * happen.  If they do, only the Blackfin maintainer cares.
+                */
+               trace_buffer_save(tflags);
 
                new_cplb_addr = (data ? bfin_read_DCPLB_FAULT_ADDR() : bfin_read_ICPLB_FAULT_ADDR()) & ~(4 * 1024 * 1024 - 1);
 
@@ -156,6 +164,7 @@ void trap_c(struct pt_regs *regs)
                for (i = 0; i < 16; ++i)
                        debug("%2i 0x%p 0x%08X\n", i, *CPLB_ADDR++, *CPLB_DATA++);
 
+               trace_buffer_restore(tflags);
                break;
        }