linux/arch/blackfin/mach-common/irqpanic.c
Robin Getz 13fe24f37d [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>
2008-01-27 15:38:56 +08:00

146 lines
4.2 KiB
C

/*
* File: arch/blackfin/mach-common/irqpanic.c
* Based on:
* Author:
*
* Created: ?
* Description: panic kernel with dump information
*
* Modified: rgetz - added cache checking code 14Feb06
* Copyright 2004-2006 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/module.h>
#include <linux/kernel_stat.h>
#include <linux/sched.h>
#include <asm/traps.h>
#include <asm/blackfin.h>
#include "../oprofile/op_blackfin.h"
#ifdef CONFIG_DEBUG_ICACHE_CHECK
#define L1_ICACHE_START 0xffa10000
#define L1_ICACHE_END 0xffa13fff
void irq_panic(int reason, struct pt_regs *regs) __attribute__ ((l1_text));
#endif
/*
* irq_panic - calls panic with string setup
*/
asmlinkage void irq_panic(int reason, struct pt_regs *regs)
{
#ifdef CONFIG_DEBUG_ICACHE_CHECK
unsigned int cmd, tag, ca, cache_hi, cache_lo, *pa;
unsigned short i, j, die;
unsigned int bad[10][6];
/* check entire cache for coherency
* Since printk is in cacheable memory,
* don't call it until you have checked everything
*/
die = 0;
i = 0;
/* check icache */
for (ca = L1_ICACHE_START; ca <= L1_ICACHE_END && i < 10; ca += 32) {
/* Grab various address bits for the itest_cmd fields */
cmd = (((ca & 0x3000) << 4) | /* ca[13:12] for SBNK[1:0] */
((ca & 0x0c00) << 16) | /* ca[11:10] for WAYSEL[1:0] */
((ca & 0x3f8)) | /* ca[09:03] for SET[4:0] and DW[1:0] */
0); /* Access Tag, Read access */
SSYNC();
bfin_write_ITEST_COMMAND(cmd);
SSYNC();
tag = bfin_read_ITEST_DATA0();
SSYNC();
/* if tag is marked as valid, check it */
if (tag & 1) {
/* The icache is arranged in 4 groups of 64-bits */
for (j = 0; j < 32; j += 8) {
cmd = ((((ca + j) & 0x3000) << 4) | /* ca[13:12] for SBNK[1:0] */
(((ca + j) & 0x0c00) << 16) | /* ca[11:10] for WAYSEL[1:0] */
(((ca + j) & 0x3f8)) | /* ca[09:03] for SET[4:0] and DW[1:0] */
4); /* Access Data, Read access */
SSYNC();
bfin_write_ITEST_COMMAND(cmd);
SSYNC();
cache_hi = bfin_read_ITEST_DATA1();
cache_lo = bfin_read_ITEST_DATA0();
pa = ((unsigned int *)((tag & 0xffffcc00) |
((ca + j) & ~(0xffffcc00))));
/*
* Debugging this, enable
*
* printk("addr: %08x %08x%08x | %08x%08x\n",
* ((unsigned int *)((tag & 0xffffcc00) | ((ca+j) & ~(0xffffcc00)))),
* cache_hi, cache_lo, *(pa+1), *pa);
*/
if (cache_hi != *(pa + 1) || cache_lo != *pa) {
/* Since icache is not working, stay out of it, by not printing */
die = 1;
bad[i][0] = (ca + j);
bad[i][1] = cache_hi;
bad[i][2] = cache_lo;
bad[i][3] = ((tag & 0xffffcc00) |
((ca + j) & ~(0xffffcc00)));
bad[i][4] = *(pa + 1);
bad[i][5] = *(pa);
i++;
}
}
}
}
if (die) {
printk(KERN_EMERG "icache coherency error\n");
for (j = 0; j <= i; j++) {
printk(KERN_EMERG
"cache address : %08x cache value : %08x%08x\n",
bad[j][0], bad[j][1], bad[j][2]);
printk(KERN_EMERG
"physical address: %08x SDRAM value : %08x%08x\n",
bad[j][3], bad[j][4], bad[j][5]);
}
panic("icache coherency error");
} else {
printk(KERN_EMERG "icache checked, and OK\n");
}
#endif
}
#ifdef CONFIG_HARDWARE_PM
/*
* call the handler of Performance overflow
*/
asmlinkage void pm_overflow(int irq, struct pt_regs *regs)
{
pm_overflow_handler(irq, regs);
}
#endif