/*
* Copyright (C) 2002,2003 Broadcom Corporation
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/*
* The Bus Watcher monitors internal bus transactions and maintains
* counts of transactions with error status, logging details and
* causing one of several interrupts. This driver provides a handler
* for those interrupts which aggregates the counts (to avoid
* saturating the 8-bit counters) and provides a presence in
* /proc/bus_watcher if PROC_FS is on.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/sibyte/sb1250.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_int.h>
#include <asm/sibyte/sb1250_scd.h>
struct bw_stats_struct {
uint64_t status;
uint32_t l2_err;
uint32_t memio_err;
int status_printed;
unsigned long l2_cor_d;
unsigned long l2_bad_d;
unsigned long l2_cor_t;
unsigned long l2_bad_t;
unsigned long mem_cor_d;
unsigned long mem_bad_d;
unsigned long bus_error;
} bw_stats;
static void print_summary(uint32_t status, uint32_t l2_err,
uint32_t memio_err)
{
printk("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
printk("\nLast recorded signature:\n");
printk("Request %02x from %d, answered by %d with Dcode %d\n",
(unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
(int)(G_SCD_BERR_TID(status) >> 6),
(int)G_SCD_BERR_RID(status),
(int)G_SCD_BERR_DCODE(status));
}
/*
* check_bus_watcher is exported for use in situations where we want
* to see the most recent status of the bus watcher, which might have
* already been destructively read out of the registers.
*
* notes: this is currently used by the cache error handler
* should provide locking against the interrupt handler
*/
void check_bus_watcher(void)
{
u32 status, l2_err, memio_err;
#ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
/* Destructive read, clears register and interrupt */
status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
#else
/* Use non-destructive register */
status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG));
#endif
if (!(status & 0x7fffffff)) {
printk("Using last values reaped by bus watcher driver\n");
status = bw_stats.status;
l2_err = bw_stats.l2_err;
memio_err = bw_stats.memio_err;
} else {
l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
}
if (status & ~(1UL << 31))
print_summary(status, l2_err, memio_err);
else
printk("Bus watcher indicates no error\n");
}
static int bw_print_buffer(char *page, struct bw_stats_struct *stats)
{
int len;
len = sprintf(page, "SiByte Bus Watcher statistics\n");
len += sprintf(page+len, "-----------------------------\n");
len += sprintf(page+len, "L2-d-cor %8ld\nL2-d-bad %8ld\n",
stats->l2_cor_d, stats->l2_bad_d);
len += sprintf(page+len, "L2-t-cor %8ld\nL2-t-bad %8ld\n",
stats->l2_cor_t, stats->l2_bad_t);
len += sprintf(page+len, "MC-d-cor %8ld\nMC-d-bad %8ld\n",
stats->mem_cor_d, stats->mem_bad_d);
len += sprintf(page+len, "IO-err %8ld\n", stats->bus_error);
len += sprintf(page+len, "\nLast recorded signature:\n");
len += sprintf(page+len, "Request %02x from %d, answered by %d with Dcode %d\n",
(unsigned int)(G_SCD_BERR_TID(stats->status) & 0x3f),
(int)(G_SCD_BERR_TID(stats->status) >> 6),
(int)G_SCD_BERR_RID(stats->status),
(int)G_SCD_BERR_DCODE(stats->status));
/* XXXKW indicate multiple errors between printings, or stats
collection (or both)? */
if (stats->status & M_SCD_BERR_MULTERRS)
len += sprintf(page+len, "Multiple errors observed since last check.\n");
if (stats->status_printed) {
len += sprintf(page+len, "(no change since last printing)\n");
} else {
stats->status_printed = 1;
}
return len;
}
#ifdef CONFIG_PROC_FS
/* For simplicity, I want to assume a single read is required each
time */
static int bw_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
int len;
if (off == 0) {
len = bw_print_buffer(page, data);
*start = page;
} else {
len = 0;
*eof = 1;
}
return len;
}
static void create_proc_decoder(struct bw_stats_struct *stats)
{
struct proc_dir_entry *ent;
ent = create_proc_read_entry("bus_watcher", S_IWUSR | S_IRUGO, NULL,
bw_read_proc, stats);
if (!ent) {
printk(KERN_INFO "Unable to initialize bus_watcher /proc entry\n");
return;
}
}
#endif /* CONFIG_PROC_FS */
/*
* sibyte_bw_int - handle bus watcher interrupts and accumulate counts
*
* notes: possible re-entry due to multiple sources
* should check/indicate saturation
*/
static irqreturn_t sibyte_bw_int(int irq, void *data, struct pt_regs *regs)
{
struct bw_stats_struct *stats = data;
unsigned long cntr;
#ifdef CONFIG_SIBYTE_BW_TRACE
int i;
#endif
#ifndef CONFIG_PROC_FS
char bw_buf[1024];
#endif
#ifdef CONFIG_SIBYTE_BW_TRACE
csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG));
csr_out32(M_SCD_TRACE_CFG_START_READ, IOADDR(A_SCD_TRACE_CFG));
for (i=0; i<256*6; i++)
printk("%016llx\n",
(unsigned long long)bus_readq(IOADDR(A_SCD_TRACE_READ)));
csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
#endif
/* Destructive read, clears register and interrupt */
stats->status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
stats->status_printed = 0;
stats->l2_err = cntr = csr_in32(IOADDR(A_BUS_L2_ERRORS));
stats->l2_cor_d += G_SCD_L2ECC_CORR_D(cntr);
stats->l2_bad_d += G_SCD_L2ECC_BAD_D(cntr);
stats->l2_cor_t += G_SCD_L2ECC_CORR_T(cntr);
stats->l2_bad_t += G_SCD_L2ECC_BAD_T(cntr);
csr_out32(0, IOADDR(A_BUS_L2_ERRORS));
stats->memio_err = cntr = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
stats->mem_cor_d += G_SCD_MEM_ECC_CORR(cntr);
stats->mem_bad_d += G_SCD_MEM_ECC_BAD(cntr);
stats->bus_error += G_SCD_MEM_BUSERR(cntr);
csr_out32(0, IOADDR(A_BUS_MEM_IO_ERRORS));
#ifndef CONFIG_PROC_FS
bw_print_buffer(bw_buf, stats);
printk(bw_buf);
#endif
return IRQ_HANDLED;
}
int __init sibyte_bus_watcher(void)
{
memset(&bw_stats, 0, sizeof(struct bw_stats_struct));
bw_stats.status_printed = 1;
if (request_irq(K_INT_BAD_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
printk("Failed to register bus watcher BAD_ECC irq\n");
return -1;
}
if (request_irq(K_INT_COR_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
free_irq(K_INT_BAD_ECC, &bw_stats);
printk("Failed to register bus watcher COR_ECC irq\n");
return -1;
}
if (request_irq(K_INT_IO_BUS, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
free_irq(K_INT_BAD_ECC, &bw_stats);
free_irq(K_INT_COR_ECC, &bw_stats);
printk("Failed to register bus watcher IO_BUS irq\n");
return -1;
}
#ifdef CONFIG_PROC_FS
create_proc_decoder(&bw_stats);
#endif
#ifdef CONFIG_SIBYTE_BW_TRACE
csr_out32((M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
K_SCD_TRSEQ_TRIGGER_ALL),
IOADDR(A_SCD_TRACE_SEQUENCE_0));
csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
#endif
return 0;
}
__initcall(sibyte_bus_watcher);
