patch-2.4.22 linux-2.4.22/arch/mips/sibyte/sb1250/bus_watcher.c

• Lines: 233
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/arch/mips/sibyte/sb1250/bus_watcher.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/arch/mips/sibyte/sb1250/bus_watcher.c linux-2.4.22/arch/mips/sibyte/sb1250/bus_watcher.c
@@ -0,0 +1,232 @@
+/*
+ * 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/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+#include <asm/system.h>
+
+#include <asm/sibyte/sb1250.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_int.h>
+#include <asm/sibyte/sb1250_scd.h>
+#include <asm/sibyte/64bit.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(IO_SPACE_BASE | A_SCD_BUS_ERR_STATUS);
+#else
+	/* Use non-destructive register */
+	status = csr_in32(IO_SPACE_BASE | 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(IO_SPACE_BASE | A_BUS_L2_ERRORS);
+		memio_err = csr_in32(IO_SPACE_BASE | 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 void sibyte_bw_int(int irq, void *data, struct pt_regs *regs)
+{
+	struct bw_stats_struct *stats = data;
+	unsigned long cntr;
+#ifndef CONFIG_PROC_FS
+	char bw_buf[1024];
+#endif
+
+	/* Destructive read, clears register and interrupt */
+	stats->status = csr_in32(IO_SPACE_BASE | A_SCD_BUS_ERR_STATUS);
+	stats->status_printed = 0;
+
+	stats->l2_err = cntr = csr_in32(IO_SPACE_BASE | 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, IO_SPACE_BASE | A_BUS_L2_ERRORS);
+
+	stats->memio_err = cntr = csr_in32(IO_SPACE_BASE | 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, IO_SPACE_BASE | A_BUS_MEM_IO_ERRORS);
+
+#ifndef CONFIG_PROC_FS
+	bw_print_buffer(bw_buf, stats);
+	printk(bw_buf);
+#endif
+}
+
+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
+
+	return 0;
+}
+
+__initcall(sibyte_bus_watcher);