i7core_edac: Add edac_mce glue

Adds a glue code to allow i7core to work with mcelog. With the glue,
i7core registers itself on edac_mce. At mce, when an error is detected,
it calls all registered drivers (in this case, i7core), for EDAC error
handling.

TODO: It currently just prints the MCE error log using about the same
      format as mce panic messages. The error message should be enhanced
      with mcelog userspace info and converted into the proper EDAC format,
      to feed the EDAC error counts.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 116 insertions, 6 deletions

diff --git a/drivers/edac/edac_mce.c b/drivers/edac/edac_mce.c
index b1efa8e5192..9ccdc5b140e 100644
--- a/drivers/edac/edac_mce.c
+++ b/drivers/edac/edac_mce.c
@@ -41,9 +41,7 @@ void edac_mce_unregister(struct edac_mce *edac_mce)
 }
 EXPORT_SYMBOL(edac_mce_unregister);
 
-
-
-int edac_mce_queue(struct mce *mce)
+int edac_mce_parse(struct mce *mce)
 {
         struct edac_mce *edac_mce;
 
@@ -55,4 +53,9 @@ int edac_mce_queue(struct mce *mce)
         /* Nobody queued the error */
         return 0;
 }
-EXPORT_SYMBOL_GPL(edac_mce_queue);
+EXPORT_SYMBOL_GPL(edac_mce_parse);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
+MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
+MODULE_DESCRIPTION("EDAC Driver for mcelog captured errors");
diff --git a/drivers/edac/i7core_edac.c b/drivers/edac/i7core_edac.c
index 91491475969..3c7bb5f405f 100644
--- a/drivers/edac/i7core_edac.c
+++ b/drivers/edac/i7core_edac.c
@@ -27,6 +27,8 @@
 #include <linux/slab.h>
 #include <linux/edac.h>
 #include <linux/mmzone.h>
+#include <linux/edac_mce.h>
+#include <linux/spinlock.h>
 
 #include "edac_core.h"
 
@@ -195,6 +197,11 @@ struct i7core_pvt {
         unsigned long   ce_count[MAX_DIMMS];    /* ECC corrected errors counts per dimm */
         int             last_ce_count[MAX_DIMMS];
 
+        /* mcelog glue */
+        struct edac_mce         edac_mce;
+        struct mce              mce_entry[MCE_LOG_LEN];
+        unsigned                mce_count;
+        spinlock_t              mce_lock;
 };
 
 /* Device name and register DID (Device ID) */
@@ -900,7 +907,7 @@ static ssize_t i7core_inject_enable_store(struct mem_ctl_info *mci,
         pci_read_config_dword(pvt->pci_ch[pvt->inject.channel][0],
                                MC_CHANNEL_ADDR_MATCH + 4, &rdmask2);
 
-        debugf0("Inject addr match write 0x%016llx, read: 0x%08x%08x\n",
+        debugf0("Inject addr match write 0x%016llx, read: 0x%08x 0x%08x\n",
                 mask, rdmask1, rdmask2);
 #endif
 #endif
@@ -1162,9 +1169,11 @@ static void check_mc_test_err(struct mem_ctl_info *mci)
         new1 = DIMM1_COR_ERR(rcv0);
         new0 = DIMM0_COR_ERR(rcv0);
 
+#if 0
         debugf2("%s CE rcv1=0x%08x rcv0=0x%08x, %d %d %d\n",
                 (pvt->ce_count_available ? "UPDATE" : "READ"),
                 rcv1, rcv0, new0, new1, new2);
+#endif
 
         /* Updates CE counters if it is not the first time here */
         if (pvt->ce_count_available) {
@@ -1195,16 +1204,97 @@ static void check_mc_test_err(struct mem_ctl_info *mci)
         pvt->last_ce_count[0] = new0;
 }
 
+static void i7core_mce_output_error(struct mem_ctl_info *mci,
+                                    struct mce *m)
+{
+        debugf0("CPU %d: Machine Check Exception: %16Lx"
+                "Bank %d: %016Lx\n",
+                m->cpu, m->mcgstatus, m->bank, m->status);
+        if (m->ip) {
+                debugf0("RIP%s %02x:<%016Lx>\n",
+                        !(m->mcgstatus & MCG_STATUS_EIPV) ? " !INEXACT!" : "",
+                        m->cs, m->ip);
+        }
+        printk(KERN_EMERG "TSC %llx ", m->tsc);
+        if (m->addr)
+                printk("ADDR %llx ", m->addr);
+        if (m->misc)
+                printk("MISC %llx ", m->misc);
+
+#if 0
+        snprintf(msg, sizeof(msg),
+                "%s (Branch=%d DRAM-Bank=%d Buffer ID = %d RDWR=%s "
+                "RAS=%d CAS=%d %s Err=0x%lx (%s))",
+                type, branch >> 1, bank, buf_id, rdwr_str(rdwr), ras, cas,
+                type, allErrors, error_name[errnum]);
+
+        /* Call the helper to output message */
+        edac_mc_handle_fbd_ue(mci, rank, channel, channel + 1, msg);
+#endif
+}
+
 /*
  *      i7core_check_error      Retrieve and process errors reported by the
  *                              hardware. Called by the Core module.
  */
 static void i7core_check_error(struct mem_ctl_info *mci)
 {
+        struct i7core_pvt *pvt = mci->pvt_info;
+        int i;
+        unsigned count = 0;
+        struct mce *m = NULL;
+        unsigned long flags;
+
+        debugf0(__FILE__ ": %s()\n", __func__);
+
+        /* Copy all mce errors into a temporary buffer */
+        spin_lock_irqsave(&pvt->mce_lock, flags);
+        if (pvt->mce_count) {
+                m = kmalloc(sizeof(*m) * pvt->mce_count, GFP_ATOMIC);
+                if (m) {
+                        count = pvt->mce_count;
+                        memcpy(m, &pvt->mce_entry, sizeof(*m) * count);
+                }
+                pvt->mce_count = 0;
+        }
+        spin_unlock_irqrestore(&pvt->mce_lock, flags);
+
+        /* proccess mcelog errors */
+        for (i = 0; i < count; i++)
+                i7core_mce_output_error(mci, &m[i]);
+
+        kfree(m);
+
+        /* check memory count errors */
         check_mc_test_err(mci);
 }
 
 /*
+ * i7core_mce_check_error       Replicates mcelog routine to get errors
+ *                              This routine simply queues mcelog errors, and
+ *                              return. The error itself should be handled later
+ *                              by i7core_check_error.
+ */
+static int i7core_mce_check_error(void *priv, struct mce *mce)
+{
+        struct i7core_pvt *pvt = priv;
+        unsigned long flags;
+
+        debugf0(__FILE__ ": %s()\n", __func__);
+
+        spin_lock_irqsave(&pvt->mce_lock, flags);
+        if (pvt->mce_count < MCE_LOG_LEN) {
+                memcpy(&pvt->mce_entry[pvt->mce_count], mce, sizeof(*mce));
+                pvt->mce_count++;
+        }
+        spin_unlock_irqrestore(&pvt->mce_lock, flags);
+
+        /* Advice mcelog that the error were handled */
+//      return 1;
+        return 0; // Let's duplicate the log
+}
+
+/*
  *      i7core_probe    Probe for ONE instance of device to see if it is
  *                      present.
  *      return:
@@ -1305,6 +1395,18 @@ static int __devinit i7core_probe(struct pci_dev *pdev,
         pvt->inject.page = -1;
         pvt->inject.col = -1;
 
+        /* Registers on edac_mce in order to receive memory errors */
+        pvt->edac_mce.priv = pvt;
+        pvt->edac_mce.check_error = i7core_mce_check_error;
+        spin_lock_init(&pvt->mce_lock);
+
+        rc = edac_mce_register(&pvt->edac_mce);
+        if (unlikely (rc < 0)) {
+                debugf0("MC: " __FILE__
+                        ": %s(): failed edac_mce_register()\n", __func__);
+                goto fail1;
+        }
+
         i7core_printk(KERN_INFO, "Driver loaded.\n");
 
         return 0;
@@ -1324,17 +1426,22 @@ fail0:
 static void __devexit i7core_remove(struct pci_dev *pdev)
 {
         struct mem_ctl_info *mci;
+        struct i7core_pvt *pvt;
 
         debugf0(__FILE__ ": %s()\n", __func__);
 
         if (i7core_pci)
                 edac_pci_release_generic_ctl(i7core_pci);
 
-        mci = edac_mc_del_mc(&pdev->dev);
 
+        mci = edac_mc_del_mc(&pdev->dev);
         if (!mci)
                 return;
 
+        /* Unregisters on edac_mce in order to receive memory errors */
+        pvt = mci->pvt_info;
+        edac_mce_unregister(&pvt->edac_mce);
+
         /* retrieve references to resources, and free those resources */
         i7core_put_devices();