7 files changed, 174 insertions, 7 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 7bdaf5080408..395d1a013ebb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1824,6 +1824,12 @@ and is between 256 and 4096 characters. It is defined in the file
                                 PAGE_SIZE is used as alignment.
                                 PCI-PCI bridge can be specified, if resource
                                 windows need to be expanded.
+                ecrc=           Enable/disable PCIe ECRC (transaction layer
+                                end-to-end CRC checking).
+                                bios: Use BIOS/firmware settings. This is the
+                                the default.
+                                off: Turn ECRC off
+                                on: Turn ECRC on.
 
         pcie_aspm=      [PCIE] Forcibly enable or disable PCIe Active State Power
                         Management.
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 761557688b18..56fb18d2cb52 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2588,6 +2588,8 @@ static int __init pci_setup(char *str)
                         } else if (!strncmp(str, "resource_alignment=", 19)) {
                                 pci_set_resource_alignment_param(str + 19,
                                                         strlen(str + 19));
+                        } else if (!strncmp(str, "ecrc=", 5)) {
+                                pcie_ecrc_get_policy(str + 5);
                         } else {
                                 printk(KERN_ERR "PCI: Unknown option `%s'\n",
                                                 str);
diff --git a/drivers/pci/pcie/aer/Kconfig b/drivers/pci/pcie/aer/Kconfig
index c3bde588aa13..db4cb950933a 100644
--- a/drivers/pci/pcie/aer/Kconfig
+++ b/drivers/pci/pcie/aer/Kconfig
@@ -10,3 +10,16 @@ config PCIEAER
           This enables PCI Express Root Port Advanced Error Reporting
           (AER) driver support. Error reporting messages sent to Root
           Port will be handled by PCI Express AER driver.
+
+
+#
+# PCI Express ECRC
+#
+config PCIE_ECRC
+        bool "PCI Express ECRC settings control"
+        depends on PCIEAER
+        help
+          Used to override firmware/bios settings for PCI Express ECRC
+          (transaction layer end-to-end CRC checking).
+
+          When in doubt, say N.
diff --git a/drivers/pci/pcie/aer/Makefile b/drivers/pci/pcie/aer/Makefile
index 8da3bd8455a8..7f93411c56e5 100644
--- a/drivers/pci/pcie/aer/Makefile
+++ b/drivers/pci/pcie/aer/Makefile
@@ -4,6 +4,8 @@
 
 obj-$(CONFIG_PCIEAER) += aerdriver.o
 
+obj-$(CONFIG_PCIE_ECRC) += ecrc.o
+
 aerdriver-objs := aerdrv_errprint.o aerdrv_core.o aerdrv.o
 aerdriver-$(CONFIG_ACPI) += aerdrv_acpi.o
 
diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
index 307452f30035..dd3829e68e3f 100644
--- a/drivers/pci/pcie/aer/aerdrv_core.c
+++ b/drivers/pci/pcie/aer/aerdrv_core.c
@@ -113,15 +113,17 @@ static void set_device_error_reporting(struct pci_dev *dev, void *data)
 {
         bool enable = *((bool *)data);
 
-        if (dev->pcie_type != PCIE_RC_PORT &&
-            dev->pcie_type != PCIE_SW_UPSTREAM_PORT &&
-            dev->pcie_type != PCIE_SW_DOWNSTREAM_PORT)
-                return;
+        if (dev->pcie_type == PCIE_RC_PORT ||
+            dev->pcie_type == PCIE_SW_UPSTREAM_PORT ||
+            dev->pcie_type == PCIE_SW_DOWNSTREAM_PORT) {
+                if (enable)
+                        pci_enable_pcie_error_reporting(dev);
+                else
+                        pci_disable_pcie_error_reporting(dev);
+        }
 
         if (enable)
-                pci_enable_pcie_error_reporting(dev);
-        else
-                pci_disable_pcie_error_reporting(dev);
+                pcie_set_ecrc_checking(dev);
 }
 
 /**
diff --git a/drivers/pci/pcie/aer/ecrc.c b/drivers/pci/pcie/aer/ecrc.c
new file mode 100644
index 000000000000..ece97df4df6d
--- /dev/null
+++ b/drivers/pci/pcie/aer/ecrc.c
@@ -0,0 +1,131 @@
+/*
+ *    Enables/disables PCIe ECRC checking.
+ *
+ *    (C) Copyright 2009 Hewlett-Packard Development Company, L.P.
+ *    Andrew Patterson <andrew.patterson@hp.com>
+ *
+ *    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; version 2 of the License.
+ *
+ *    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/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/errno.h>
+#include "../../pci.h"
+
+#define ECRC_POLICY_DEFAULT 0           /* ECRC set by BIOS */
+#define ECRC_POLICY_OFF     1           /* ECRC off for performance */
+#define ECRC_POLICY_ON      2           /* ECRC on for data integrity */
+
+static int ecrc_policy = ECRC_POLICY_DEFAULT;
+
+static const char *ecrc_policy_str[] = {
+        [ECRC_POLICY_DEFAULT] = "bios",
+        [ECRC_POLICY_OFF] = "off",
+        [ECRC_POLICY_ON] = "on"
+};
+
+/**
+ * enable_ercr_checking - enable PCIe ECRC checking for a device
+ * @dev: the PCI device
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+static int enable_ecrc_checking(struct pci_dev *dev)
+{
+        int pos;
+        u32 reg32;
+
+        if (!dev->is_pcie)
+                return -ENODEV;
+
+        pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
+        if (!pos)
+                return -ENODEV;
+
+        pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
+        if (reg32 & PCI_ERR_CAP_ECRC_GENC)
+                reg32 |= PCI_ERR_CAP_ECRC_GENE;
+        if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
+                reg32 |= PCI_ERR_CAP_ECRC_CHKE;
+        pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
+
+        return 0;
+}
+
+/**
+ * disable_ercr_checking - disables PCIe ECRC checking for a device
+ * @dev: the PCI device
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+static int disable_ecrc_checking(struct pci_dev *dev)
+{
+        int pos;
+        u32 reg32;
+
+        if (!dev->is_pcie)
+                return -ENODEV;
+
+        pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
+        if (!pos)
+                return -ENODEV;
+
+        pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
+        reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
+        pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
+
+        return 0;
+}
+
+/**
+ * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based on global policy
+ * @dev: the PCI device
+ */
+void pcie_set_ecrc_checking(struct pci_dev *dev)
+{
+        switch (ecrc_policy) {
+        case ECRC_POLICY_DEFAULT:
+                return;
+        case ECRC_POLICY_OFF:
+                disable_ecrc_checking(dev);
+                break;
+        case ECRC_POLICY_ON:
+                enable_ecrc_checking(dev);;
+                break;
+        default:
+                return;
+        }
+}
+
+/**
+ * pcie_ecrc_get_policy - parse kernel command-line ecrc option
+ */
+void pcie_ecrc_get_policy(char *str)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(ecrc_policy_str); i++)
+                if (!strncmp(str, ecrc_policy_str[i],
+                             strlen(ecrc_policy_str[i])))
+                        break;
+        if (i >= ARRAY_SIZE(ecrc_policy_str))
+                return;
+
+        ecrc_policy = i;
+}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 19ee92c53ef7..ec03b90d3510 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -878,6 +878,17 @@ static inline int pcie_aspm_enabled(void)
 extern int pcie_aspm_enabled(void);
 #endif
 
+#ifndef CONFIG_PCIE_ECRC
+static inline void pcie_set_ecrc_checking(struct pci_dev *dev)
+{
+        return;
+}
+static inline void pcie_ecrc_get_policy(char *str) {};
+#else
+extern void pcie_set_ecrc_checking(struct pci_dev *dev);
+extern void pcie_ecrc_get_policy(char *str);
+#endif
+
 #define pci_enable_msi(pdev)    pci_enable_msi_block(pdev, 1)
 
 #ifdef CONFIG_HT_IRQ