dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

[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>
This commit is contained in:
Robin Getz 2008-01-27 15:38:56 +08:00 committed by Bryan Wu
parent f53e86760e
commit 13fe24f37d
5 changed files with 98 additions and 70 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

54
arch/blackfin/kernel/traps.c
View File

@ -433,6 +433,36 @@ asmlinkage void trap_c(struct pt_regs *fp)
/* 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 @@ asmlinkage void trap_c(struct pt_regs *fp)
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 @@ void dump_bfin_mem(void *retaddr)
* 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 @@ void show_regs(struct pt_regs *fp)
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 @@ void show_regs(struct pt_regs *fp)
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());

22
arch/blackfin/mach-common/cplbmgr.S
View File

@ -190,7 +190,14 @@ ENTRY(_cplb_mgr)
[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 @@ ENTRY(_cplb_mgr)
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;

38
arch/blackfin/mach-common/interrupt.S
View File

@ -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 @@ __common_int_entry:
/* 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 @@ ENTRY(_evt_ivhw)
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 @@ ENTRY(_evt_ivhw)
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 @@ ENTRY(_evt_ivhw)
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:

50
arch/blackfin/mach-common/irqpanic.c
View File

@ -46,9 +46,6 @@ void irq_panic(int reason, struct pt_regs *regs) __attribute__ ((l1_text));
*/
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 @@ asmlinkage void irq_panic(int reason, struct pt_regs *regs)
}
#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

4
include/asm-blackfin/traps.h
View File

@ -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__