Blackfin: cleanup code a bit with comments and defines
Improve the assembly with a few explanatory comments and use symbolic
defines rather than numeric values for bit positions.
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index 5a4e7c7..fb1795d 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -218,7 +218,7 @@
/* Single stepping only a single instruction, so clear the trace
* bit here. */
r7 = syscfg;
- bitclr (r7, 0);
+ bitclr (r7, SYSCFG_SSSTEP_P);
syscfg = R7;
jump _ex_trap_c;
@@ -251,7 +251,7 @@
if !cc jump _bfin_return_from_exception;
r7 = syscfg;
- bitclr (r7, 0);
+ bitclr (r7, SYSCFG_SSSTEP_P); /* Turn off single step */
syscfg = R7;
/* Fall through to _bfin_return_from_exception. */
@@ -342,9 +342,11 @@
r6 = retx;
[p5 + PDA_RETX] = r6;
#endif
+ /* Save the state of single stepping */
r6 = SYSCFG;
[p5 + PDA_SYSCFG] = r6;
- BITCLR(r6, 0);
+ /* Clear it while we handle the exception in IRQ5 mode */
+ BITCLR(r6, SYSCFG_SSSTEP_P);
SYSCFG = r6;
/* Disable all interrupts, but make sure level 5 is enabled so
@@ -367,7 +369,7 @@
* exception. This is a unrecoverable event, so crash.
* Note: this cannot be ENTRY() as we jump here with "if cc jump" ...
*/
-_double_fault:
+ENTRY(_double_fault)
/* Turn caches & protection off, to ensure we don't get any more
* double exceptions
*/
@@ -872,7 +874,7 @@
raise 15; /* raise evt15 to do signal or reschedule */
4:
r0 = syscfg;
- bitclr(r0, 0);
+ bitclr(r0, SYSCFG_SSSTEP_P); /* Turn off single step */
syscfg = r0;
5:
rts;
