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>
This commit is contained in:
Robin Getz 2009-06-17 15:18:18 +00:00 committed by Mike Frysinger
parent 35b5c55fee
commit 1997660cea
1 changed files with 7 additions and 5 deletions

View File

@ -218,7 +218,7 @@ ENTRY(_ex_single_step)
/* 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 @@ ENTRY(_ex_single_step)
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 @@ ENTRY(_ex_trap_c)
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 @@ ENDPROC(_ex_trap_c)
* 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 @@ ENTRY(_ret_from_exception)
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;