edac: AMD8131 driver source file

Introduce AMD8131 EDAC driver source file, which makes use of error
detections on the PCI-X Bridge Controllers on the AMD8131 HyperTransport
PCI-X Tunnel.

Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Cc: Doug Thompson <norsk5@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/edac/amd8131_edac.c b/drivers/edac/amd8131_edac.c
new file mode 100644
index 0000000..c083b31
--- /dev/null
+++ b/drivers/edac/amd8131_edac.c
@@ -0,0 +1,379 @@
+/*
+ * amd8131_edac.c, AMD8131 hypertransport chip EDAC kernel module
+ *
+ * Copyright (c) 2008 Wind River Systems, Inc.
+ *
+ * Authors:	Cao Qingtao <qingtao.cao@windriver.com>
+ * 		Benjamin Walsh <benjamin.walsh@windriver.com>
+ * 		Hu Yongqi <yongqi.hu@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/bitops.h>
+#include <linux/edac.h>
+#include <linux/pci_ids.h>
+
+#include "edac_core.h"
+#include "edac_module.h"
+#include "amd8131_edac.h"
+
+#define AMD8131_EDAC_REVISION	" Ver: 1.0.0 " __DATE__
+#define AMD8131_EDAC_MOD_STR	"amd8131_edac"
+
+/* Wrapper functions for accessing PCI configuration space */
+static void edac_pci_read_dword(struct pci_dev *dev, int reg, u32 *val32)
+{
+	int ret;
+
+	ret = pci_read_config_dword(dev, reg, val32);
+	if (ret != 0)
+		printk(KERN_ERR AMD8131_EDAC_MOD_STR
+			" PCI Access Read Error at 0x%x\n", reg);
+}
+
+static void edac_pci_write_dword(struct pci_dev *dev, int reg, u32 val32)
+{
+	int ret;
+
+	ret = pci_write_config_dword(dev, reg, val32);
+	if (ret != 0)
+		printk(KERN_ERR AMD8131_EDAC_MOD_STR
+			" PCI Access Write Error at 0x%x\n", reg);
+}
+
+static char * const bridge_str[] = {
+	[NORTH_A] = "NORTH A",
+	[NORTH_B] = "NORTH B",
+	[SOUTH_A] = "SOUTH A",
+	[SOUTH_B] = "SOUTH B",
+	[NO_BRIDGE] = "NO BRIDGE",
+};
+
+/* Support up to two AMD8131 chipsets on a platform */
+static struct amd8131_dev_info amd8131_devices[] = {
+	{
+	.inst = NORTH_A,
+	.devfn = DEVFN_PCIX_BRIDGE_NORTH_A,
+	.ctl_name = "AMD8131_PCIX_NORTH_A",
+	},
+	{
+	.inst = NORTH_B,
+	.devfn = DEVFN_PCIX_BRIDGE_NORTH_B,
+	.ctl_name = "AMD8131_PCIX_NORTH_B",
+	},
+	{
+	.inst = SOUTH_A,
+	.devfn = DEVFN_PCIX_BRIDGE_SOUTH_A,
+	.ctl_name = "AMD8131_PCIX_SOUTH_A",
+	},
+	{
+	.inst = SOUTH_B,
+	.devfn = DEVFN_PCIX_BRIDGE_SOUTH_B,
+	.ctl_name = "AMD8131_PCIX_SOUTH_B",
+	},
+	{.inst = NO_BRIDGE,},
+};
+
+static void amd8131_pcix_init(struct amd8131_dev_info *dev_info)
+{
+	u32 val32;
+	struct pci_dev *dev = dev_info->dev;
+
+	/* First clear error detection flags */
+	edac_pci_read_dword(dev, REG_MEM_LIM, &val32);
+	if (val32 & MEM_LIMIT_MASK)
+		edac_pci_write_dword(dev, REG_MEM_LIM, val32);
+
+	/* Clear Discard Timer Timedout flag */
+	edac_pci_read_dword(dev, REG_INT_CTLR, &val32);
+	if (val32 & INT_CTLR_DTS)
+		edac_pci_write_dword(dev, REG_INT_CTLR, val32);
+
+	/* Clear CRC Error flag on link side A */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_A, &val32);
+	if (val32 & LNK_CTRL_CRCERR_A)
+		edac_pci_write_dword(dev, REG_LNK_CTRL_A, val32);
+
+	/* Clear CRC Error flag on link side B */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_B, &val32);
+	if (val32 & LNK_CTRL_CRCERR_B)
+		edac_pci_write_dword(dev, REG_LNK_CTRL_B, val32);
+
+	/*
+	 * Then enable all error detections.
+	 *
+	 * Setup Discard Timer Sync Flood Enable,
+	 * System Error Enable and Parity Error Enable.
+	 */
+	edac_pci_read_dword(dev, REG_INT_CTLR, &val32);
+	val32 |= INT_CTLR_PERR | INT_CTLR_SERR | INT_CTLR_DTSE;
+	edac_pci_write_dword(dev, REG_INT_CTLR, val32);
+
+	/* Enable overall SERR Error detection */
+	edac_pci_read_dword(dev, REG_STS_CMD, &val32);
+	val32 |= STS_CMD_SERREN;
+	edac_pci_write_dword(dev, REG_STS_CMD, val32);
+
+	/* Setup CRC Flood Enable for link side A */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_A, &val32);
+	val32 |= LNK_CTRL_CRCFEN;
+	edac_pci_write_dword(dev, REG_LNK_CTRL_A, val32);
+
+	/* Setup CRC Flood Enable for link side B */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_B, &val32);
+	val32 |= LNK_CTRL_CRCFEN;
+	edac_pci_write_dword(dev, REG_LNK_CTRL_B, val32);
+}
+
+static void amd8131_pcix_exit(struct amd8131_dev_info *dev_info)
+{
+	u32 val32;
+	struct pci_dev *dev = dev_info->dev;
+
+	/* Disable SERR, PERR and DTSE Error detection */
+	edac_pci_read_dword(dev, REG_INT_CTLR, &val32);
+	val32 &= ~(INT_CTLR_PERR | INT_CTLR_SERR | INT_CTLR_DTSE);
+	edac_pci_write_dword(dev, REG_INT_CTLR, val32);
+
+	/* Disable overall System Error detection */
+	edac_pci_read_dword(dev, REG_STS_CMD, &val32);
+	val32 &= ~STS_CMD_SERREN;
+	edac_pci_write_dword(dev, REG_STS_CMD, val32);
+
+	/* Disable CRC Sync Flood on link side A */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_A, &val32);
+	val32 &= ~LNK_CTRL_CRCFEN;
+	edac_pci_write_dword(dev, REG_LNK_CTRL_A, val32);
+
+	/* Disable CRC Sync Flood on link side B */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_B, &val32);
+	val32 &= ~LNK_CTRL_CRCFEN;
+	edac_pci_write_dword(dev, REG_LNK_CTRL_B, val32);
+}
+
+static void amd8131_pcix_check(struct edac_pci_ctl_info *edac_dev)
+{
+	struct amd8131_dev_info *dev_info = edac_dev->pvt_info;
+	struct pci_dev *dev = dev_info->dev;
+	u32 val32;
+
+	/* Check PCI-X Bridge Memory Base-Limit Register for errors */
+	edac_pci_read_dword(dev, REG_MEM_LIM, &val32);
+	if (val32 & MEM_LIMIT_MASK) {
+		printk(KERN_INFO "Error(s) in mem limit register "
+			"on %s bridge\n", dev_info->ctl_name);
+		printk(KERN_INFO "DPE: %d, RSE: %d, RMA: %d\n"
+			"RTA: %d, STA: %d, MDPE: %d\n",
+			val32 & MEM_LIMIT_DPE,
+			val32 & MEM_LIMIT_RSE,
+			val32 & MEM_LIMIT_RMA,
+			val32 & MEM_LIMIT_RTA,
+			val32 & MEM_LIMIT_STA,
+			val32 & MEM_LIMIT_MDPE);
+
+		val32 |= MEM_LIMIT_MASK;
+		edac_pci_write_dword(dev, REG_MEM_LIM, val32);
+
+		edac_pci_handle_npe(edac_dev, edac_dev->ctl_name);
+	}
+
+	/* Check if Discard Timer timed out */
+	edac_pci_read_dword(dev, REG_INT_CTLR, &val32);
+	if (val32 & INT_CTLR_DTS) {
+		printk(KERN_INFO "Error(s) in interrupt and control register "
+			"on %s bridge\n", dev_info->ctl_name);
+		printk(KERN_INFO "DTS: %d\n", val32 & INT_CTLR_DTS);
+
+		val32 |= INT_CTLR_DTS;
+		edac_pci_write_dword(dev, REG_INT_CTLR, val32);
+
+		edac_pci_handle_npe(edac_dev, edac_dev->ctl_name);
+	}
+
+	/* Check if CRC error happens on link side A */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_A, &val32);
+	if (val32 & LNK_CTRL_CRCERR_A) {
+		printk(KERN_INFO "Error(s) in link conf and control register "
+			"on %s bridge\n", dev_info->ctl_name);
+		printk(KERN_INFO "CRCERR: %d\n", val32 & LNK_CTRL_CRCERR_A);
+
+		val32 |= LNK_CTRL_CRCERR_A;
+		edac_pci_write_dword(dev, REG_LNK_CTRL_A, val32);
+
+		edac_pci_handle_npe(edac_dev, edac_dev->ctl_name);
+	}
+
+	/* Check if CRC error happens on link side B */
+	edac_pci_read_dword(dev, REG_LNK_CTRL_B, &val32);
+	if (val32 & LNK_CTRL_CRCERR_B) {
+		printk(KERN_INFO "Error(s) in link conf and control register "
+			"on %s bridge\n", dev_info->ctl_name);
+		printk(KERN_INFO "CRCERR: %d\n", val32 & LNK_CTRL_CRCERR_B);
+
+		val32 |= LNK_CTRL_CRCERR_B;
+		edac_pci_write_dword(dev, REG_LNK_CTRL_B, val32);
+
+		edac_pci_handle_npe(edac_dev, edac_dev->ctl_name);
+	}
+}
+
+static struct amd8131_info amd8131_chipset = {
+	.err_dev = PCI_DEVICE_ID_AMD_8131_APIC,
+	.devices = amd8131_devices,
+	.init = amd8131_pcix_init,
+	.exit = amd8131_pcix_exit,
+	.check = amd8131_pcix_check,
+};
+
+/*
+ * There are 4 PCIX Bridges on ATCA-6101 that share the same PCI Device ID,
+ * so amd8131_probe() would be called by kernel 4 times, with different
+ * address of pci_dev for each of them each time.
+ */
+static int amd8131_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	struct amd8131_dev_info *dev_info;
+
+	for (dev_info = amd8131_chipset.devices; dev_info->inst != NO_BRIDGE;
+		dev_info++)
+		if (dev_info->devfn == dev->devfn)
+			break;
+
+	if (dev_info->inst == NO_BRIDGE) /* should never happen */
+		return -ENODEV;
+
+	/*
+	 * We can't call pci_get_device() as we are used to do because
+	 * there are 4 of them but pci_dev_get() instead.
+	 */
+	dev_info->dev = pci_dev_get(dev);
+
+	if (pci_enable_device(dev_info->dev)) {
+		pci_dev_put(dev_info->dev);
+		printk(KERN_ERR "failed to enable:"
+			"vendor %x, device %x, devfn %x, name %s\n",
+			PCI_VENDOR_ID_AMD, amd8131_chipset.err_dev,
+			dev_info->devfn, dev_info->ctl_name);
+		return -ENODEV;
+	}
+
+	/*
+	 * we do not allocate extra private structure for
+	 * edac_pci_ctl_info, but make use of existing
+	 * one instead.
+	 */
+	dev_info->edac_idx = edac_pci_alloc_index();
+	dev_info->edac_dev = edac_pci_alloc_ctl_info(0, dev_info->ctl_name);
+	if (!dev_info->edac_dev)
+		return -ENOMEM;
+
+	dev_info->edac_dev->pvt_info = dev_info;
+	dev_info->edac_dev->dev = &dev_info->dev->dev;
+	dev_info->edac_dev->mod_name = AMD8131_EDAC_MOD_STR;
+	dev_info->edac_dev->ctl_name = dev_info->ctl_name;
+	dev_info->edac_dev->dev_name = dev_info->dev->dev.bus_id;
+
+	if (edac_op_state == EDAC_OPSTATE_POLL)
+		dev_info->edac_dev->edac_check = amd8131_chipset.check;
+
+	if (amd8131_chipset.init)
+		amd8131_chipset.init(dev_info);
+
+	if (edac_pci_add_device(dev_info->edac_dev, dev_info->edac_idx) > 0) {
+		printk(KERN_ERR "failed edac_pci_add_device() for %s\n",
+			dev_info->ctl_name);
+		edac_pci_free_ctl_info(dev_info->edac_dev);
+		return -ENODEV;
+	}
+
+	printk(KERN_INFO "added one device on AMD8131 "
+		"vendor %x, device %x, devfn %x, name %s\n",
+		PCI_VENDOR_ID_AMD, amd8131_chipset.err_dev,
+		dev_info->devfn, dev_info->ctl_name);
+
+	return 0;
+}
+
+static void amd8131_remove(struct pci_dev *dev)
+{
+	struct amd8131_dev_info *dev_info;
+
+	for (dev_info = amd8131_chipset.devices; dev_info->inst != NO_BRIDGE;
+		dev_info++)
+		if (dev_info->devfn == dev->devfn)
+			break;
+
+	if (dev_info->inst == NO_BRIDGE) /* should never happen */
+		return;
+
+	if (dev_info->edac_dev) {
+		edac_pci_del_device(dev_info->edac_dev->dev);
+		edac_pci_free_ctl_info(dev_info->edac_dev);
+	}
+
+	if (amd8131_chipset.exit)
+		amd8131_chipset.exit(dev_info);
+
+	pci_dev_put(dev_info->dev);
+}
+
+static const struct pci_device_id amd8131_edac_pci_tbl[] = {
+	{
+	PCI_VEND_DEV(AMD, 8131_BRIDGE),
+	.subvendor = PCI_ANY_ID,
+	.subdevice = PCI_ANY_ID,
+	.class = 0,
+	.class_mask = 0,
+	.driver_data = 0,
+	},
+	{
+	0,
+	}			/* table is NULL-terminated */
+};
+MODULE_DEVICE_TABLE(pci, amd8131_edac_pci_tbl);
+
+static struct pci_driver amd8131_edac_driver = {
+	.name = AMD8131_EDAC_MOD_STR,
+	.probe = amd8131_probe,
+	.remove = amd8131_remove,
+	.id_table = amd8131_edac_pci_tbl,
+};
+
+static int __init amd8131_edac_init(void)
+{
+	printk(KERN_INFO "AMD8131 EDAC driver " AMD8131_EDAC_REVISION "\n");
+	printk(KERN_INFO "\t(c) 2008 Wind River Systems, Inc.\n");
+
+	/* Only POLL mode supported so far */
+	edac_op_state = EDAC_OPSTATE_POLL;
+
+	return pci_register_driver(&amd8131_edac_driver);
+}
+
+static void __exit amd8131_edac_exit(void)
+{
+	pci_unregister_driver(&amd8131_edac_driver);
+}
+
+module_init(amd8131_edac_init);
+module_exit(amd8131_edac_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Cao Qingtao <qingtao.cao@windriver.com>\n");
+MODULE_DESCRIPTION("AMD8131 HyperTransport PCI-X Tunnel EDAC kernel module");