[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/kernel/traps.c b/arch/blackfin/kernel/traps.c
index 21a55ef..4be5ff0 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -433,6 +433,36 @@
/* 0x3D - Reserved, Caught by default */
/* 0x3E - Reserved, Caught by default */
/* 0x3F - Reserved, Caught by default */
+ case VEC_HWERR:
+ info.si_code = BUS_ADRALN;
+ sig = SIGBUS;
+ switch (fp->seqstat & SEQSTAT_HWERRCAUSE) {
+ /* System MMR Error */
+ case (SEQSTAT_HWERRCAUSE_SYSTEM_MMR):
+ info.si_code = BUS_ADRALN;
+ sig = SIGBUS;
+ printk(KERN_NOTICE HWC_x2(KERN_NOTICE));
+ break;
+ /* External Memory Addressing Error */
+ case (SEQSTAT_HWERRCAUSE_EXTERN_ADDR):
+ info.si_code = BUS_ADRERR;
+ sig = SIGBUS;
+ printk(KERN_NOTICE HWC_x3(KERN_NOTICE));
+ break;
+ /* Performance Monitor Overflow */
+ case (SEQSTAT_HWERRCAUSE_PERF_FLOW):
+ printk(KERN_NOTICE HWC_x12(KERN_NOTICE));
+ break;
+ /* RAISE 5 instruction */
+ case (SEQSTAT_HWERRCAUSE_RAISE_5):
+ printk(KERN_NOTICE HWC_x18(KERN_NOTICE));
+ break;
+ default: /* Reserved */
+ printk(KERN_NOTICE HWC_default(KERN_NOTICE));
+ break;
+ }
+ CHK_DEBUGGER_TRAP();
+ break;
default:
info.si_code = TRAP_ILLTRAP;
sig = SIGTRAP;
@@ -447,7 +477,11 @@
if (sig != SIGTRAP) {
unsigned long stack;
dump_bfin_process(fp);
- dump_bfin_mem((void *)fp->retx);
+ /* Is it an interrupt, or an exception? */
+ if (trapnr == VEC_HWERR)
+ dump_bfin_mem((void *)fp->pc);
+ else
+ dump_bfin_mem((void *)fp->retx);
show_regs(fp);
/* Print out the trace buffer if it makes sense */
@@ -672,12 +706,11 @@
* context, which should mean an oops is happening
*/
if (oops_in_progress && x >= 0x0040 && x <= 0x0047 && i <= 0)
- panic("\n\nWARNING : You should reconfigure"
+ printk(KERN_EMERG "\n"
+ KERN_EMERG "WARNING : You should reconfigure"
" the kernel to turn on\n"
- " 'Hardware error interrupt"
- " debugging'\n"
- " The rest of this error"
- " is meanless\n");
+ KERN_EMERG " 'Hardware error interrupt debugging'\n"
+ KERN_EMERG " The rest of this error is meanless\n");
#endif
if (i == (unsigned int)retaddr)
printk("[%04x]", x);
@@ -698,6 +731,10 @@
printk(KERN_NOTICE "\n" KERN_NOTICE "SEQUENCER STATUS:\n");
printk(KERN_NOTICE " SEQSTAT: %08lx IPEND: %04lx SYSCFG: %04lx\n",
(long)fp->seqstat, fp->ipend, fp->syscfg);
+ printk(KERN_NOTICE " HWERRCAUSE: 0x%lx\n",
+ (fp->seqstat & SEQSTAT_HWERRCAUSE) >> 14);
+ printk(KERN_NOTICE " EXCAUSE : 0x%lx\n",
+ fp->seqstat & SEQSTAT_EXCAUSE);
decode_address(buf, fp->rete);
printk(KERN_NOTICE " RETE: %s\n", buf);
@@ -708,9 +745,10 @@
decode_address(buf, fp->rets);
printk(KERN_NOTICE " RETS: %s\n", buf);
decode_address(buf, fp->pc);
- printk(KERN_NOTICE " PC: %s\n", buf);
+ printk(KERN_NOTICE " PC : %s\n", buf);
- if ((long)fp->seqstat & SEQSTAT_EXCAUSE) {
+ if (((long)fp->seqstat & SEQSTAT_EXCAUSE) &&
+ (((long)fp->seqstat & SEQSTAT_EXCAUSE) != VEC_HWERR)) {
decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
diff --git a/arch/blackfin/mach-common/cplbmgr.S b/arch/blackfin/mach-common/cplbmgr.S
index faca1ab..f5cf3ac 100644
--- a/arch/blackfin/mach-common/cplbmgr.S
+++ b/arch/blackfin/mach-common/cplbmgr.S
@@ -190,7 +190,14 @@
[P0 - 4] = R0;
R0 = [P0 - 0x100];
[P0-0x104] = R0;
-.Lie_move:P0+=4;
+.Lie_move:
+ P0+=4;
+
+ /* Clear ICPLB_DATA15, in case we don't find a replacement
+ * otherwise, we would have a duplicate entry, and will crash
+ */
+ R0 = 0;
+ [P0 - 4] = R0;
/* We've made space in the ICPLB table, so that ICPLB15
* is now free to be overwritten. Next, we have to determine
@@ -515,14 +522,23 @@
R0 = [P0++]; /* move data */
[P0 - 8] = R0;
R0 = [P0-0x104] /* move address */
-.Lde_move: [P0-0x108] = R0;
+.Lde_move:
+ [P0-0x108] = R0;
+
+.Lde_moved:
+ NOP;
+
+ /* Clear DCPLB_DATA15, in case we don't find a replacement
+ * otherwise, we would have a duplicate entry, and will crash
+ */
+ R0 = 0;
+ [P0 - 0x4] = R0;
/* We've now made space in DCPLB15 for the new CPLB to be
* installed. The next stage is to locate a CPLB in the
* config table that covers the faulting address.
*/
-.Lde_moved:NOP;
R0 = I0; /* Our faulting address */
P2.L = _dpdt_table;
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:
diff --git a/arch/blackfin/mach-common/irqpanic.c b/arch/blackfin/mach-common/irqpanic.c
index b22959b..606ded9 100644
--- a/arch/blackfin/mach-common/irqpanic.c
+++ b/arch/blackfin/mach-common/irqpanic.c
@@ -46,9 +46,6 @@
*/
asmlinkage void irq_panic(int reason, struct pt_regs *regs)
{
- int sig = 0;
- siginfo_t info;
-
#ifdef CONFIG_DEBUG_ICACHE_CHECK
unsigned int cmd, tag, ca, cache_hi, cache_lo, *pa;
unsigned short i, j, die;
@@ -136,53 +133,6 @@
}
#endif
- printk(KERN_EMERG "\n");
- printk(KERN_EMERG "Exception: IRQ 0x%x entered\n", reason);
- printk(KERN_EMERG " code=[0x%08lx], stack frame=0x%08lx, "
- " bad PC=0x%08lx\n",
- (unsigned long)regs->seqstat,
- (unsigned long)regs,
- (unsigned long)regs->pc);
- if (reason == 0x5) {
- printk(KERN_EMERG "----------- HARDWARE ERROR -----------\n");
-
- /* There is only need to check for Hardware Errors, since other
- * EXCEPTIONS are handled in TRAPS.c (MH)
- */
- switch (regs->seqstat & SEQSTAT_HWERRCAUSE) {
- case (SEQSTAT_HWERRCAUSE_SYSTEM_MMR): /* System MMR Error */
- info.si_code = BUS_ADRALN;
- sig = SIGBUS;
- printk(KERN_EMERG HWC_x2(KERN_EMERG));
- break;
- case (SEQSTAT_HWERRCAUSE_EXTERN_ADDR): /* External Memory Addressing Error */
- info.si_code = BUS_ADRERR;
- sig = SIGBUS;
- printk(KERN_EMERG HWC_x3(KERN_EMERG));
- break;
- case (SEQSTAT_HWERRCAUSE_PERF_FLOW): /* Performance Monitor Overflow */
- printk(KERN_EMERG HWC_x12(KERN_EMERG));
- break;
- case (SEQSTAT_HWERRCAUSE_RAISE_5): /* RAISE 5 instruction */
- printk(KERN_EMERG HWC_x18(KERN_EMERG));
- break;
- default: /* Reserved */
- printk(KERN_EMERG HWC_default(KERN_EMERG));
- break;
- }
- }
-
- regs->ipend = bfin_read_IPEND();
- dump_bfin_process(regs);
- dump_bfin_mem((void *)regs->pc);
- show_regs(regs);
- if (0 == (info.si_signo = sig) || 0 == user_mode(regs)) /* in kernelspace */
- panic("Unhandled IRQ or exceptions!\n");
- else { /* in userspace */
- info.si_errno = 0;
- info.si_addr = (void *)regs->pc;
- force_sig_info(sig, &info, current);
- }
}
#ifdef CONFIG_HARDWARE_PM
diff --git a/include/asm-blackfin/traps.h b/include/asm-blackfin/traps.h
index ee1cbf7..f0e5f94 100644
--- a/include/asm-blackfin/traps.h
+++ b/include/asm-blackfin/traps.h
@@ -45,6 +45,10 @@
#define VEC_CPLB_I_M (44)
#define VEC_CPLB_I_MHIT (45)
#define VEC_ILL_RES (46) /* including unvalid supervisor mode insn */
+/* The hardware reserves (63) for future use - we use it to tell our
+ * normal exception handling code we have a hardware error
+ */
+#define VEC_HWERR (63)
#ifndef __ASSEMBLY__
