[IB] mthca: first pass at catastrophic error reporting

Add some initial support for detecting and reporting catastrophic
errors reported by Mellanox HCAs.  We start a periodic timer which
polls the catastrophic error reporting buffer in device memory.  If an
error is detected, we dump the contents of the buffer for port-mortem
debugging, and report a fatal asynchronous error to higher levels.

In the future we can try to recover from these errors by resetting the
device, but this will require some work in higher-level code as well.
Let's get this in now, so that we at least get catastrophic errors
reported in logs.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_catas.c b/drivers/infiniband/hw/mthca/mthca_catas.c
new file mode 100644
index 0000000..7ac52af
--- /dev/null
+++ b/drivers/infiniband/hw/mthca/mthca_catas.c
@@ -0,0 +1,153 @@
+/*
+ * Copyright (c) 2005 Cisco Systems.  All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * $Id$
+ */
+
+#include "mthca_dev.h"
+
+enum {
+	MTHCA_CATAS_POLL_INTERVAL	= 5 * HZ,
+
+	MTHCA_CATAS_TYPE_INTERNAL	= 0,
+	MTHCA_CATAS_TYPE_UPLINK		= 3,
+	MTHCA_CATAS_TYPE_DDR		= 4,
+	MTHCA_CATAS_TYPE_PARITY		= 5,
+};
+
+static DEFINE_SPINLOCK(catas_lock);
+
+static void handle_catas(struct mthca_dev *dev)
+{
+	struct ib_event event;
+	const char *type;
+	int i;
+
+	event.device = &dev->ib_dev;
+	event.event  = IB_EVENT_DEVICE_FATAL;
+	event.element.port_num = 0;
+
+	ib_dispatch_event(&event);
+
+	switch (swab32(readl(dev->catas_err.map)) >> 24) {
+	case MTHCA_CATAS_TYPE_INTERNAL:
+		type = "internal error";
+		break;
+	case MTHCA_CATAS_TYPE_UPLINK:
+		type = "uplink bus error";
+		break;
+	case MTHCA_CATAS_TYPE_DDR:
+		type = "DDR data error";
+		break;
+	case MTHCA_CATAS_TYPE_PARITY:
+		type = "internal parity error";
+		break;
+	default:
+		type = "unknown error";
+		break;
+	}
+
+	mthca_err(dev, "Catastrophic error detected: %s\n", type);
+	for (i = 0; i < dev->catas_err.size; ++i)
+		mthca_err(dev, "  buf[%02x]: %08x\n",
+			  i, swab32(readl(dev->catas_err.map + i)));
+}
+
+static void poll_catas(unsigned long dev_ptr)
+{
+	struct mthca_dev *dev = (struct mthca_dev *) dev_ptr;
+	unsigned long flags;
+	int i;
+
+	for (i = 0; i < dev->catas_err.size; ++i)
+		if (readl(dev->catas_err.map + i)) {
+			handle_catas(dev);
+			return;
+		}
+
+	spin_lock_irqsave(&catas_lock, flags);
+	if (dev->catas_err.stop)
+		mod_timer(&dev->catas_err.timer,
+			  jiffies + MTHCA_CATAS_POLL_INTERVAL);
+	spin_unlock_irqrestore(&catas_lock, flags);
+
+	return;
+}
+
+void mthca_start_catas_poll(struct mthca_dev *dev)
+{
+	unsigned long addr;
+
+	init_timer(&dev->catas_err.timer);
+	dev->catas_err.stop = 0;
+	dev->catas_err.map  = NULL;
+
+	addr = pci_resource_start(dev->pdev, 0) +
+		((pci_resource_len(dev->pdev, 0) - 1) &
+		 dev->catas_err.addr);
+
+	if (!request_mem_region(addr, dev->catas_err.size * 4,
+				DRV_NAME)) {
+		mthca_warn(dev, "couldn't request catastrophic error region "
+			   "at 0x%lx/0x%x\n", addr, dev->catas_err.size * 4);
+		return;
+	}
+
+	dev->catas_err.map = ioremap(addr, dev->catas_err.size * 4);
+	if (!dev->catas_err.map) {
+		mthca_warn(dev, "couldn't map catastrophic error region "
+			   "at 0x%lx/0x%x\n", addr, dev->catas_err.size * 4);
+		release_mem_region(addr, dev->catas_err.size * 4);
+		return;
+	}
+
+	dev->catas_err.timer.data     = (unsigned long) dev;
+	dev->catas_err.timer.function = poll_catas;
+	dev->catas_err.timer.expires  = jiffies + MTHCA_CATAS_POLL_INTERVAL;
+	add_timer(&dev->catas_err.timer);
+}
+
+void mthca_stop_catas_poll(struct mthca_dev *dev)
+{
+	spin_lock_irq(&catas_lock);
+	dev->catas_err.stop = 1;
+	spin_unlock_irq(&catas_lock);
+
+	del_timer_sync(&dev->catas_err.timer);
+
+	if (dev->catas_err.map) {
+		iounmap(dev->catas_err.map);
+		release_mem_region(pci_resource_start(dev->pdev, 0) +
+				   ((pci_resource_len(dev->pdev, 0) - 1) &
+				    dev->catas_err.addr),
+				   dev->catas_err.size * 4);
+	}
+}