[Blackfin] arch: fix bug - trap_tests fails to recover on some tests.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3719
When the CPLBs get a miss, we do:
- find a victim in the HW table
- remove the victim
- find the replacement in the software table
- put it into the HW table.
If we can't find a replacement in the software table, we accidently
leave a duplicate in the HW table. This patch ensures that duplicate
is marked as not valid.
What we should do is find the replacement in the software table, before
we find a victim in the HW table - but its too late in the release cycle
to do that much restructuring of this code.
Rather that duplicate code, connect Hardware Errors (irq5) into trap_c,
so user space processes get killed properly.
The rest of irq_panic() can be moved into traps.c (later)
There is still a small corner case that causes problems when a
pheriperal interrupt goes off a single cycle before a user space
hardware error. This causes a kernel panic, rather than the user
space process being killed.
But, this checkin makes things work in 99.9% of the cases, and is a vast
improvement from what is there today (which fails 100% of the time).
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
diff --git a/arch/blackfin/mach-common/interrupt.S b/arch/blackfin/mach-common/interrupt.S
index 4de3764..f983ac7 100644
--- a/arch/blackfin/mach-common/interrupt.S
+++ b/arch/blackfin/mach-common/interrupt.S
@@ -34,9 +34,13 @@
#include <asm/entry.h>
#include <asm/asm-offsets.h>
#include <asm/trace.h>
+#include <asm/traps.h>
+#include <asm/thread_info.h>
#include <asm/mach-common/context.S>
+.extern _ret_from_exception
+
#ifdef CONFIG_I_ENTRY_L1
.section .l1.text
#else
@@ -134,10 +138,11 @@
/* interrupt routine for ivhw - 5 */
ENTRY(_evt_ivhw)
- SAVE_CONTEXT
+ SAVE_ALL_SYS
#ifdef CONFIG_FRAME_POINTER
fp = 0;
#endif
+
#if ANOMALY_05000283
cc = r7 == r7;
p5.h = 0xffc0;
@@ -147,13 +152,8 @@
1:
#endif
- trace_buffer_stop(p0, r0);
-
- r0 = IRQ_HWERR;
- r1 = sp;
-
#ifdef CONFIG_HARDWARE_PM
- r7 = SEQSTAT;
+ r7 = [sp + PT_SEQSTAT];
r7 = r7 >>> 0xe;
r6 = 0x1F;
r7 = r7 & r6;
@@ -161,11 +161,29 @@
cc = r7 == r5;
if cc jump .Lcall_do_ovf; /* deal with performance counter overflow */
#endif
+ # We are going to dump something out, so make sure we print IPEND properly
+ p2.l = lo(IPEND);
+ p2.h = hi(IPEND);
+ r0 = [p2];
+ [sp + PT_IPEND] = r0;
+ /* set the EXCAUSE to HWERR for trap_c */
+ r0 = [sp + PT_SEQSTAT];
+ R1.L = LO(VEC_HWERR);
+ R1.H = HI(VEC_HWERR);
+ R0 = R0 | R1;
+ [sp + PT_SEQSTAT] = R0;
+
+ r0 = sp; /* stack frame pt_regs pointer argument ==> r0 */
SP += -12;
- call _irq_panic;
+ call _trap_c;
SP += 12;
+
+ call _ret_from_exception;
+.Lcommon_restore_all_sys:
+ RESTORE_ALL_SYS
rti;
+
#ifdef CONFIG_HARDWARE_PM
.Lcall_do_ovf:
@@ -173,9 +191,11 @@
call _pm_overflow;
SP += 12;
- jump .Lcommon_restore_context;
+ jump .Lcommon_restore_all_sys;
#endif
+ENDPROC(_evt_ivhw)
+
/* Interrupt routine for evt2 (NMI).
* We don't actually use this, so just return.
* For inner circle type details, please see: