3 files changed, 82 insertions, 1 deletions

diff --git a/Documentation/drivers/edac/edac.txt b/Documentation/drivers/edac/edac.txt
index 7b3d969d2964..3c5a9e4297b4 100644
--- a/Documentation/drivers/edac/edac.txt
+++ b/Documentation/drivers/edac/edac.txt
@@ -339,7 +339,21 @@ Device Symlink:
 
         'device'
 
-        Symlink to the memory controller device
+        Symlink to the memory controller device.
+
+Sdram memory scrubbing rate:
+
+        'sdram_scrub_rate'
+
+        Read/Write attribute file that controls memory scrubbing. The scrubbing
+        rate is set by writing a minimum bandwith in bytes/sec to the attribute
+        file. The rate will be translated to an internal value that gives at
+        least the specified rate.
+
+        Reading the file will return the actual scrubbing rate employed.
+
+        If configuration fails or memory scrubbing is not implemented, the value
+        of the attribute file will be -1.
 
 
 
diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c
index 1b4fc9221803..1df8c0c5d40a 100644
--- a/drivers/edac/edac_mc.c
+++ b/drivers/edac/edac_mc.c
@@ -927,6 +927,57 @@ static ssize_t mci_reset_counters_store(struct mem_ctl_info *mci,
         return count;
 }
 
+/* memory scrubbing */
+static ssize_t mci_sdram_scrub_rate_store(struct mem_ctl_info *mci,
+                                        const char *data, size_t count)
+{
+        u32 bandwidth = -1;
+
+        if (mci->set_sdram_scrub_rate) {
+
+                memctrl_int_store(&bandwidth, data, count);
+
+                if (!(*mci->set_sdram_scrub_rate)(mci, &bandwidth)) {
+                        edac_printk(KERN_DEBUG, EDAC_MC,
+                                "Scrub rate set successfully, applied: %d\n",
+                                bandwidth);
+                } else {
+                        /* FIXME: error codes maybe? */
+                        edac_printk(KERN_DEBUG, EDAC_MC,
+                                "Scrub rate set FAILED, could not apply: %d\n",
+                                bandwidth);
+                }
+        } else {
+                /* FIXME: produce "not implemented" ERROR for user-side. */
+                edac_printk(KERN_WARNING, EDAC_MC,
+                        "Memory scrubbing 'set'control is not implemented!\n");
+        }
+        return count;
+}
+
+static ssize_t mci_sdram_scrub_rate_show(struct mem_ctl_info *mci, char *data)
+{
+        u32 bandwidth = -1;
+
+        if (mci->get_sdram_scrub_rate) {
+                if (!(*mci->get_sdram_scrub_rate)(mci, &bandwidth)) {
+                        edac_printk(KERN_DEBUG, EDAC_MC,
+                                "Scrub rate successfully, fetched: %d\n",
+                                bandwidth);
+                } else {
+                        /* FIXME: error codes maybe? */
+                        edac_printk(KERN_DEBUG, EDAC_MC,
+                                "Scrub rate fetch FAILED, got: %d\n",
+                                bandwidth);
+                }
+        } else {
+                /* FIXME: produce "not implemented" ERROR for user-side.  */
+                edac_printk(KERN_WARNING, EDAC_MC,
+                        "Memory scrubbing 'get' control is not implemented!\n");
+        }
+        return sprintf(data, "%d\n", bandwidth);
+}
+
 /* default attribute files for the MCI object */
 static ssize_t mci_ue_count_show(struct mem_ctl_info *mci, char *data)
 {
@@ -1033,6 +1084,9 @@ MCIDEV_ATTR(ce_noinfo_count,S_IRUGO,mci_ce_noinfo_show,NULL);
 MCIDEV_ATTR(ue_count,S_IRUGO,mci_ue_count_show,NULL);
 MCIDEV_ATTR(ce_count,S_IRUGO,mci_ce_count_show,NULL);
 
+/* memory scrubber attribute file */
+MCIDEV_ATTR(sdram_scrub_rate,S_IRUGO|S_IWUSR,mci_sdram_scrub_rate_show,mci_sdram_scrub_rate_store);
+
 static struct mcidev_attribute *mci_attr[] = {
         &mci_attr_reset_counters,
         &mci_attr_mc_name,
@@ -1042,6 +1096,7 @@ static struct mcidev_attribute *mci_attr[] = {
         &mci_attr_ce_noinfo_count,
         &mci_attr_ue_count,
         &mci_attr_ce_count,
+        &mci_attr_sdram_scrub_rate,
         NULL
 };
 
diff --git a/drivers/edac/edac_mc.h b/drivers/edac/edac_mc.h
index a1cfd4e3c97d..c41986a9ed5b 100644
--- a/drivers/edac/edac_mc.h
+++ b/drivers/edac/edac_mc.h
@@ -315,6 +315,18 @@ struct mem_ctl_info {
         unsigned long scrub_cap;        /* chipset scrub capabilities */
         enum scrub_type scrub_mode;     /* current scrub mode */
 
+        /* Translates sdram memory scrub rate given in bytes/sec to the
+           internal representation and configures whatever else needs
+           to be configured.
+        */
+        int (*set_sdram_scrub_rate) (struct mem_ctl_info *mci, u32 *bw);
+
+        /* Get the current sdram memory scrub rate from the internal
+           representation and converts it to the closest matching
+           bandwith in bytes/sec.
+        */
+        int (*get_sdram_scrub_rate) (struct mem_ctl_info *mci, u32 *bw);
+
         /* pointer to edac checking routine */
         void (*edac_check) (struct mem_ctl_info * mci);
         /*