edac_mc_sysfs.c

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/*
 * edac_mc kernel module
 * (C) 2005-2007 Linux Networx (http://lnxi.com)
 *
 * This file may be distributed under the terms of the
 * GNU General Public License.
 *
 * Written Doug Thompson <[email protected]> www.softwarebitmaker.com
 *
 * (c) 2012 - Mauro Carvalho Chehab <[email protected]>
 *  The entire API were re-written, and ported to use struct device
 *
 */

#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/edac.h>
#include <linux/bug.h>
#include <linux/pm_runtime.h>
#include <linux/uaccess.h>

#include "edac_core.h"
#include "edac_module.h"

/* MC EDAC Controls, setable by module parameter, and sysfs */
static int edac_mc_log_ue = 1;
static int edac_mc_log_ce = 1;
static int edac_mc_panic_on_ue;
static int edac_mc_poll_msec = 1000;

/* Getter functions for above */
int edac_mc_get_log_ue(void)
{
    return edac_mc_log_ue;
}

int edac_mc_get_log_ce(void)
{
    return edac_mc_log_ce;
}

int edac_mc_get_panic_on_ue(void)
{
    return edac_mc_panic_on_ue;
}

/* this is temporary */
int edac_mc_get_poll_msec(void)
{
    return edac_mc_poll_msec;
}

static int edac_set_poll_msec(const char *val, struct kernel_param *kp)
{
    long l;
    int ret;

    if (!val)
        return -EINVAL;

    ret = strict_strtol(val, 0, &l);
    if (ret == -EINVAL || ((int)l != l))
        return -EINVAL;
    *((int *)kp->arg) = l;

    /* notify edac_mc engine to reset the poll period */
    edac_mc_reset_delay_period(l);

    return 0;
}

/* Parameter declarations for above */
module_param(edac_mc_panic_on_ue, int, 0644);
MODULE_PARM_DESC(edac_mc_panic_on_ue, "Panic on uncorrected error: 0=off 1=on");
module_param(edac_mc_log_ue, int, 0644);
MODULE_PARM_DESC(edac_mc_log_ue,
         "Log uncorrectable error to console: 0=off 1=on");
module_param(edac_mc_log_ce, int, 0644);
MODULE_PARM_DESC(edac_mc_log_ce,
         "Log correctable error to console: 0=off 1=on");
module_param_call(edac_mc_poll_msec, edac_set_poll_msec, param_get_int,
          &edac_mc_poll_msec, 0644);
MODULE_PARM_DESC(edac_mc_poll_msec, "Polling period in milliseconds");

static struct device *mci_pdev;

/*
 * various constants for Memory Controllers
 */
static const char *mem_types[] = {
    [MEM_EMPTY] = "Empty",
    [MEM_RESERVED] = "Reserved",
    [MEM_UNKNOWN] = "Unknown",
    [MEM_FPM] = "FPM",
    [MEM_EDO] = "EDO",
    [MEM_BEDO] = "BEDO",
    [MEM_SDR] = "Unbuffered-SDR",
    [MEM_RDR] = "Registered-SDR",
    [MEM_DDR] = "Unbuffered-DDR",
    [MEM_RDDR] = "Registered-DDR",
    [MEM_RMBS] = "RMBS",
    [MEM_DDR2] = "Unbuffered-DDR2",
    [MEM_FB_DDR2] = "FullyBuffered-DDR2",
    [MEM_RDDR2] = "Registered-DDR2",
    [MEM_XDR] = "XDR",
    [MEM_DDR3] = "Unbuffered-DDR3",
    [MEM_RDDR3] = "Registered-DDR3"
};

static const char *dev_types[] = {
    [DEV_UNKNOWN] = "Unknown",
    [DEV_X1] = "x1",
    [DEV_X2] = "x2",
    [DEV_X4] = "x4",
    [DEV_X8] = "x8",
    [DEV_X16] = "x16",
    [DEV_X32] = "x32",
    [DEV_X64] = "x64"
};

static const char *edac_caps[] = {
    [EDAC_UNKNOWN] = "Unknown",
    [EDAC_NONE] = "None",
    [EDAC_RESERVED] = "Reserved",
    [EDAC_PARITY] = "PARITY",
    [EDAC_EC] = "EC",
    [EDAC_SECDED] = "SECDED",
    [EDAC_S2ECD2ED] = "S2ECD2ED",
    [EDAC_S4ECD4ED] = "S4ECD4ED",
    [EDAC_S8ECD8ED] = "S8ECD8ED",
    [EDAC_S16ECD16ED] = "S16ECD16ED"
};

#ifdef CONFIG_EDAC_LEGACY_SYSFS
/*
 * EDAC sysfs CSROW data structures and methods
 */

#define to_csrow(k) container_of(k, struct csrow_info, dev)

/*
 * We need it to avoid namespace conflicts between the legacy API
 * and the per-dimm/per-rank one
 */
#define DEVICE_ATTR_LEGACY(_name, _mode, _show, _store) \
    struct device_attribute dev_attr_legacy_##_name = __ATTR(_name, _mode, _show, _store)

struct dev_ch_attribute {
    struct device_attribute attr;
    int channel;
};

#define DEVICE_CHANNEL(_name, _mode, _show, _store, _var) \
    struct dev_ch_attribute dev_attr_legacy_##_name = \
        { __ATTR(_name, _mode, _show, _store), (_var) }

#define to_channel(k) (container_of(k, struct dev_ch_attribute, attr)->channel)

/* Set of more default csrow<id> attribute show/store functions */
static ssize_t csrow_ue_count_show(struct device *dev,
                   struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);

    return sprintf(data, "%u\n", csrow->ue_count);
}

static ssize_t csrow_ce_count_show(struct device *dev,
                   struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);

    return sprintf(data, "%u\n", csrow->ce_count);
}

static ssize_t csrow_size_show(struct device *dev,
                   struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);
    int i;
    u32 nr_pages = 0;

    for (i = 0; i < csrow->nr_channels; i++)
        nr_pages += csrow->channels[i]->dimm->nr_pages;
    return sprintf(data, "%u\n", PAGES_TO_MiB(nr_pages));
}

static ssize_t csrow_mem_type_show(struct device *dev,
                   struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);

    return sprintf(data, "%s\n", mem_types[csrow->channels[0]->dimm->mtype]);
}

static ssize_t csrow_dev_type_show(struct device *dev,
                   struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);

    return sprintf(data, "%s\n", dev_types[csrow->channels[0]->dimm->dtype]);
}

static ssize_t csrow_edac_mode_show(struct device *dev,
                    struct device_attribute *mattr,
                    char *data)
{
    struct csrow_info *csrow = to_csrow(dev);

    return sprintf(data, "%s\n", edac_caps[csrow->channels[0]->dimm->edac_mode]);
}

/* show/store functions for DIMM Label attributes */
static ssize_t channel_dimm_label_show(struct device *dev,
                       struct device_attribute *mattr,
                       char *data)
{
    struct csrow_info *csrow = to_csrow(dev);
    unsigned chan = to_channel(mattr);
    struct rank_info *rank = csrow->channels[chan];

    /* if field has not been initialized, there is nothing to send */
    if (!rank->dimm->label[0])
        return 0;

    return snprintf(data, EDAC_MC_LABEL_LEN, "%s\n",
            rank->dimm->label);
}

static ssize_t channel_dimm_label_store(struct device *dev,
                    struct device_attribute *mattr,
                    const char *data, size_t count)
{
    struct csrow_info *csrow = to_csrow(dev);
    unsigned chan = to_channel(mattr);
    struct rank_info *rank = csrow->channels[chan];

    ssize_t max_size = 0;

    max_size = min((ssize_t) count, (ssize_t) EDAC_MC_LABEL_LEN - 1);
    strncpy(rank->dimm->label, data, max_size);
    rank->dimm->label[max_size] = '\0';

    return max_size;
}

/* show function for dynamic chX_ce_count attribute */
static ssize_t channel_ce_count_show(struct device *dev,
                     struct device_attribute *mattr, char *data)
{
    struct csrow_info *csrow = to_csrow(dev);
    unsigned chan = to_channel(mattr);
    struct rank_info *rank = csrow->channels[chan];

    return sprintf(data, "%u\n", rank->ce_count);
}

/* cwrow<id>/attribute files */
DEVICE_ATTR_LEGACY(size_mb, S_IRUGO, csrow_size_show, NULL);
DEVICE_ATTR_LEGACY(dev_type, S_IRUGO, csrow_dev_type_show, NULL);
DEVICE_ATTR_LEGACY(mem_type, S_IRUGO, csrow_mem_type_show, NULL);
DEVICE_ATTR_LEGACY(edac_mode, S_IRUGO, csrow_edac_mode_show, NULL);
DEVICE_ATTR_LEGACY(ue_count, S_IRUGO, csrow_ue_count_show, NULL);
DEVICE_ATTR_LEGACY(ce_count, S_IRUGO, csrow_ce_count_show, NULL);

/* default attributes of the CSROW<id> object */
static struct attribute *csrow_attrs[] = {
    &dev_attr_legacy_dev_type.attr,
    &dev_attr_legacy_mem_type.attr,
    &dev_attr_legacy_edac_mode.attr,
    &dev_attr_legacy_size_mb.attr,
    &dev_attr_legacy_ue_count.attr,
    &dev_attr_legacy_ce_count.attr,
    NULL,
};

static struct attribute_group csrow_attr_grp = {
    .attrs  = csrow_attrs,
};

static const struct attribute_group *csrow_attr_groups[] = {
    &csrow_attr_grp,
    NULL
};

static void csrow_attr_release(struct device *dev)
{
    struct csrow_info *csrow = container_of(dev, struct csrow_info, dev);

    edac_dbg(1, "Releasing csrow device %s\n", dev_name(dev));
    kfree(csrow);
}

static struct device_type csrow_attr_type = {
    .groups     = csrow_attr_groups,
    .release    = csrow_attr_release,
};

/*
 * possible dynamic channel DIMM Label attribute files
 *
 */

#define EDAC_NR_CHANNELS    6

DEVICE_CHANNEL(ch0_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 0);
DEVICE_CHANNEL(ch1_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 1);
DEVICE_CHANNEL(ch2_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 2);
DEVICE_CHANNEL(ch3_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 3);
DEVICE_CHANNEL(ch4_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 4);
DEVICE_CHANNEL(ch5_dimm_label, S_IRUGO | S_IWUSR,
    channel_dimm_label_show, channel_dimm_label_store, 5);

/* Total possible dynamic DIMM Label attribute file table */
static struct device_attribute *dynamic_csrow_dimm_attr[] = {
    &dev_attr_legacy_ch0_dimm_label.attr,
    &dev_attr_legacy_ch1_dimm_label.attr,
    &dev_attr_legacy_ch2_dimm_label.attr,
    &dev_attr_legacy_ch3_dimm_label.attr,
    &dev_attr_legacy_ch4_dimm_label.attr,
    &dev_attr_legacy_ch5_dimm_label.attr
};

/* possible dynamic channel ce_count attribute files */
DEVICE_CHANNEL(ch0_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 0);
DEVICE_CHANNEL(ch1_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 1);
DEVICE_CHANNEL(ch2_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 2);
DEVICE_CHANNEL(ch3_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 3);
DEVICE_CHANNEL(ch4_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 4);
DEVICE_CHANNEL(ch5_ce_count, S_IRUGO | S_IWUSR,
           channel_ce_count_show, NULL, 5);

/* Total possible dynamic ce_count attribute file table */
static struct device_attribute *dynamic_csrow_ce_count_attr[] = {
    &dev_attr_legacy_ch0_ce_count.attr,
    &dev_attr_legacy_ch1_ce_count.attr,
    &dev_attr_legacy_ch2_ce_count.attr,
    &dev_attr_legacy_ch3_ce_count.attr,
    &dev_attr_legacy_ch4_ce_count.attr,
    &dev_attr_legacy_ch5_ce_count.attr
};

static inline int nr_pages_per_csrow(struct csrow_info *csrow)
{
    int chan, nr_pages = 0;

    for (chan = 0; chan < csrow->nr_channels; chan++)
        nr_pages += csrow->channels[chan]->dimm->nr_pages;

    return nr_pages;
}

/* Create a CSROW object under specifed edac_mc_device */
static int edac_create_csrow_object(struct mem_ctl_info *mci,
                    struct csrow_info *csrow, int index)
{
    int err, chan;

    if (csrow->nr_channels >= EDAC_NR_CHANNELS)
        return -ENODEV;

    csrow->dev.type = &csrow_attr_type;
    csrow->dev.bus = &mci->bus;
    device_initialize(&csrow->dev);
    csrow->dev.parent = &mci->dev;
    dev_set_name(&csrow->dev, "csrow%d", index);
    dev_set_drvdata(&csrow->dev, csrow);

    edac_dbg(0, "creating (virtual) csrow node %s\n",
         dev_name(&csrow->dev));

    err = device_add(&csrow->dev);
    if (err < 0)
        return err;

    for (chan = 0; chan < csrow->nr_channels; chan++) {
        /* Only expose populated DIMMs */
        if (!csrow->channels[chan]->dimm->nr_pages)
            continue;
        err = device_create_file(&csrow->dev,
                     dynamic_csrow_dimm_attr[chan]);
        if (err < 0)
            goto error;
        err = device_create_file(&csrow->dev,
                     dynamic_csrow_ce_count_attr[chan]);
        if (err < 0) {
            device_remove_file(&csrow->dev,
                       dynamic_csrow_dimm_attr[chan]);
            goto error;
        }
    }

    return 0;

error:
    for (--chan; chan >= 0; chan--) {
        device_remove_file(&csrow->dev,
                    dynamic_csrow_dimm_attr[chan]);
        device_remove_file(&csrow->dev,
                       dynamic_csrow_ce_count_attr[chan]);
    }
    put_device(&csrow->dev);

    return err;
}

/* Create a CSROW object under specifed edac_mc_device */
static int edac_create_csrow_objects(struct mem_ctl_info *mci)
{
    int err, i, chan;
    struct csrow_info *csrow;

    for (i = 0; i < mci->nr_csrows; i++) {
        csrow = mci->csrows[i];
        if (!nr_pages_per_csrow(csrow))
            continue;
        err = edac_create_csrow_object(mci, mci->csrows[i], i);
        if (err < 0)
            goto error;
    }
    return 0;

error:
    for (--i; i >= 0; i--) {
        csrow = mci->csrows[i];
        if (!nr_pages_per_csrow(csrow))
            continue;
        for (chan = csrow->nr_channels - 1; chan >= 0; chan--) {
            if (!csrow->channels[chan]->dimm->nr_pages)
                continue;
            device_remove_file(&csrow->dev,
                        dynamic_csrow_dimm_attr[chan]);
            device_remove_file(&csrow->dev,
                        dynamic_csrow_ce_count_attr[chan]);
        }
        put_device(&mci->csrows[i]->dev);
    }

    return err;
}

static void edac_delete_csrow_objects(struct mem_ctl_info *mci)
{
    int i, chan;
    struct csrow_info *csrow;

    for (i = mci->nr_csrows - 1; i >= 0; i--) {
        csrow = mci->csrows[i];
        if (!nr_pages_per_csrow(csrow))
            continue;
        for (chan = csrow->nr_channels - 1; chan >= 0; chan--) {
            if (!csrow->channels[chan]->dimm->nr_pages)
                continue;
            edac_dbg(1, "Removing csrow %d channel %d sysfs nodes\n",
                 i, chan);
            device_remove_file(&csrow->dev,
                        dynamic_csrow_dimm_attr[chan]);
            device_remove_file(&csrow->dev,
                        dynamic_csrow_ce_count_attr[chan]);
        }
        put_device(&mci->csrows[i]->dev);
        device_del(&mci->csrows[i]->dev);
    }
}
#endif

/*
 * Per-dimm (or per-rank) devices
 */

#define to_dimm(k) container_of(k, struct dimm_info, dev)

/* show/store functions for DIMM Label attributes */
static ssize_t dimmdev_location_show(struct device *dev,
                     struct device_attribute *mattr, char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    return edac_dimm_info_location(dimm, data, PAGE_SIZE);
}

static ssize_t dimmdev_label_show(struct device *dev,
                  struct device_attribute *mattr, char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    /* if field has not been initialized, there is nothing to send */
    if (!dimm->label[0])
        return 0;

    return snprintf(data, EDAC_MC_LABEL_LEN, "%s\n", dimm->label);
}

static ssize_t dimmdev_label_store(struct device *dev,
                   struct device_attribute *mattr,
                   const char *data,
                   size_t count)
{
    struct dimm_info *dimm = to_dimm(dev);

    ssize_t max_size = 0;

    max_size = min((ssize_t) count, (ssize_t) EDAC_MC_LABEL_LEN - 1);
    strncpy(dimm->label, data, max_size);
    dimm->label[max_size] = '\0';

    return max_size;
}

static ssize_t dimmdev_size_show(struct device *dev,
                 struct device_attribute *mattr, char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    return sprintf(data, "%u\n", PAGES_TO_MiB(dimm->nr_pages));
}

static ssize_t dimmdev_mem_type_show(struct device *dev,
                     struct device_attribute *mattr, char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    return sprintf(data, "%s\n", mem_types[dimm->mtype]);
}

static ssize_t dimmdev_dev_type_show(struct device *dev,
                     struct device_attribute *mattr, char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    return sprintf(data, "%s\n", dev_types[dimm->dtype]);
}

static ssize_t dimmdev_edac_mode_show(struct device *dev,
                      struct device_attribute *mattr,
                      char *data)
{
    struct dimm_info *dimm = to_dimm(dev);

    return sprintf(data, "%s\n", edac_caps[dimm->edac_mode]);
}

/* dimm/rank attribute files */
static DEVICE_ATTR(dimm_label, S_IRUGO | S_IWUSR,
           dimmdev_label_show, dimmdev_label_store);
static DEVICE_ATTR(dimm_location, S_IRUGO, dimmdev_location_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, dimmdev_size_show, NULL);
static DEVICE_ATTR(dimm_mem_type, S_IRUGO, dimmdev_mem_type_show, NULL);
static DEVICE_ATTR(dimm_dev_type, S_IRUGO, dimmdev_dev_type_show, NULL);
static DEVICE_ATTR(dimm_edac_mode, S_IRUGO, dimmdev_edac_mode_show, NULL);

/* attributes of the dimm<id>/rank<id> object */
static struct attribute *dimm_attrs[] = {
    &dev_attr_dimm_label.attr,
    &dev_attr_dimm_location.attr,
    &dev_attr_size.attr,
    &dev_attr_dimm_mem_type.attr,
    &dev_attr_dimm_dev_type.attr,
    &dev_attr_dimm_edac_mode.attr,
    NULL,
};

static struct attribute_group dimm_attr_grp = {
    .attrs  = dimm_attrs,
};

static const struct attribute_group *dimm_attr_groups[] = {
    &dimm_attr_grp,
    NULL
};

static void dimm_attr_release(struct device *dev)
{
    struct dimm_info *dimm = container_of(dev, struct dimm_info, dev);

    edac_dbg(1, "Releasing dimm device %s\n", dev_name(dev));
    kfree(dimm);
}

static struct device_type dimm_attr_type = {
    .groups     = dimm_attr_groups,
    .release    = dimm_attr_release,
};

/* Create a DIMM object under specifed memory controller device */
static int edac_create_dimm_object(struct mem_ctl_info *mci,
                   struct dimm_info *dimm,
                   int index)
{
    int err;
    dimm->mci = mci;

    dimm->dev.type = &dimm_attr_type;
    dimm->dev.bus = &mci->bus;
    device_initialize(&dimm->dev);

    dimm->dev.parent = &mci->dev;
    if (mci->mem_is_per_rank)
        dev_set_name(&dimm->dev, "rank%d", index);
    else
        dev_set_name(&dimm->dev, "dimm%d", index);
    dev_set_drvdata(&dimm->dev, dimm);
    pm_runtime_forbid(&mci->dev);

    err =  device_add(&dimm->dev);

    edac_dbg(0, "creating rank/dimm device %s\n", dev_name(&dimm->dev));

    return err;
}

/*
 * Memory controller device
 */

#define to_mci(k) container_of(k, struct mem_ctl_info, dev)

static ssize_t mci_reset_counters_store(struct device *dev,
                    struct device_attribute *mattr,
                    const char *data, size_t count)
{
    struct mem_ctl_info *mci = to_mci(dev);
    int cnt, row, chan, i;
    mci->ue_mc = 0;
    mci->ce_mc = 0;
    mci->ue_noinfo_count = 0;
    mci->ce_noinfo_count = 0;

    for (row = 0; row < mci->nr_csrows; row++) {
        struct csrow_info *ri = mci->csrows[row];

        ri->ue_count = 0;
        ri->ce_count = 0;

        for (chan = 0; chan < ri->nr_channels; chan++)
            ri->channels[chan]->ce_count = 0;
    }

    cnt = 1;
    for (i = 0; i < mci->n_layers; i++) {
        cnt *= mci->layers[i].size;
        memset(mci->ce_per_layer[i], 0, cnt * sizeof(u32));
        memset(mci->ue_per_layer[i], 0, cnt * sizeof(u32));
    }

    mci->start_time = jiffies;
    return count;
}

/* Memory scrubbing interface:
 *
 * A MC driver can limit the scrubbing bandwidth based on the CPU type.
 * Therefore, ->set_sdram_scrub_rate should be made to return the actual
 * bandwidth that is accepted or 0 when scrubbing is to be disabled.
 *
 * Negative value still means that an error has occurred while setting
 * the scrub rate.
 */
static ssize_t mci_sdram_scrub_rate_store(struct device *dev,
                      struct device_attribute *mattr,
                      const char *data, size_t count)
{
    struct mem_ctl_info *mci = to_mci(dev);
    unsigned long bandwidth = 0;
    int new_bw = 0;

    if (!mci->set_sdram_scrub_rate)
        return -ENODEV;

    if (strict_strtoul(data, 10, &bandwidth) < 0)
        return -EINVAL;

    new_bw = mci->set_sdram_scrub_rate(mci, bandwidth);
    if (new_bw < 0) {
        edac_printk(KERN_WARNING, EDAC_MC,
                "Error setting scrub rate to: %lu\n", bandwidth);
        return -EINVAL;
    }

    return count;
}

/*
 * ->get_sdram_scrub_rate() return value semantics same as above.
 */
static ssize_t mci_sdram_scrub_rate_show(struct device *dev,
                     struct device_attribute *mattr,
                     char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);
    int bandwidth = 0;

    if (!mci->get_sdram_scrub_rate)
        return -ENODEV;

    bandwidth = mci->get_sdram_scrub_rate(mci);
    if (bandwidth < 0) {
        edac_printk(KERN_DEBUG, EDAC_MC, "Error reading scrub rate\n");
        return bandwidth;
    }

    return sprintf(data, "%d\n", bandwidth);
}

/* default attribute files for the MCI object */
static ssize_t mci_ue_count_show(struct device *dev,
                 struct device_attribute *mattr,
                 char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%d\n", mci->ue_mc);
}

static ssize_t mci_ce_count_show(struct device *dev,
                 struct device_attribute *mattr,
                 char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%d\n", mci->ce_mc);
}

static ssize_t mci_ce_noinfo_show(struct device *dev,
                  struct device_attribute *mattr,
                  char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%d\n", mci->ce_noinfo_count);
}

static ssize_t mci_ue_noinfo_show(struct device *dev,
                  struct device_attribute *mattr,
                  char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%d\n", mci->ue_noinfo_count);
}

static ssize_t mci_seconds_show(struct device *dev,
                struct device_attribute *mattr,
                char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%ld\n", (jiffies - mci->start_time) / HZ);
}

static ssize_t mci_ctl_name_show(struct device *dev,
                 struct device_attribute *mattr,
                 char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);

    return sprintf(data, "%s\n", mci->ctl_name);
}

static ssize_t mci_size_mb_show(struct device *dev,
                struct device_attribute *mattr,
                char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);
    int total_pages = 0, csrow_idx, j;

    for (csrow_idx = 0; csrow_idx < mci->nr_csrows; csrow_idx++) {
        struct csrow_info *csrow = mci->csrows[csrow_idx];

        for (j = 0; j < csrow->nr_channels; j++) {
            struct dimm_info *dimm = csrow->channels[j]->dimm;

            total_pages += dimm->nr_pages;
        }
    }

    return sprintf(data, "%u\n", PAGES_TO_MiB(total_pages));
}

static ssize_t mci_max_location_show(struct device *dev,
                     struct device_attribute *mattr,
                     char *data)
{
    struct mem_ctl_info *mci = to_mci(dev);
    int i;
    char *p = data;

    for (i = 0; i < mci->n_layers; i++) {
        p += sprintf(p, "%s %d ",
                 edac_layer_name[mci->layers[i].type],
                 mci->layers[i].size - 1);
    }

    return p - data;
}

#ifdef CONFIG_EDAC_DEBUG
static ssize_t edac_fake_inject_write(struct file *file,
                      const char __user *data,
                      size_t count, loff_t *ppos)
{
    struct device *dev = file->private_data;
    struct mem_ctl_info *mci = to_mci(dev);
    static enum hw_event_mc_err_type type;
    u16 errcount = mci->fake_inject_count;

    if (!errcount)
        errcount = 1;

    type = mci->fake_inject_ue ? HW_EVENT_ERR_UNCORRECTED
                   : HW_EVENT_ERR_CORRECTED;

    printk(KERN_DEBUG
           "Generating %d %s fake error%s to %d.%d.%d to test core handling. NOTE: this won't test the driver-specific decoding logic.\n",
        errcount,
        (type == HW_EVENT_ERR_UNCORRECTED) ? "UE" : "CE",
        errcount > 1 ? "s" : "",
        mci->fake_inject_layer[0],
        mci->fake_inject_layer[1],
        mci->fake_inject_layer[2]
           );
    edac_mc_handle_error(type, mci, errcount, 0, 0, 0,
                 mci->fake_inject_layer[0],
                 mci->fake_inject_layer[1],
                 mci->fake_inject_layer[2],
                 "FAKE ERROR", "for EDAC testing only");

    return count;
}

static int debugfs_open(struct inode *inode, struct file *file)
{
    file->private_data = inode->i_private;
    return 0;
}

static const struct file_operations debug_fake_inject_fops = {
    .open = debugfs_open,
    .write = edac_fake_inject_write,
    .llseek = generic_file_llseek,
};
#endif

/* default Control file */
DEVICE_ATTR(reset_counters, S_IWUSR, NULL, mci_reset_counters_store);

/* default Attribute files */
DEVICE_ATTR(mc_name, S_IRUGO, mci_ctl_name_show, NULL);
DEVICE_ATTR(size_mb, S_IRUGO, mci_size_mb_show, NULL);
DEVICE_ATTR(seconds_since_reset, S_IRUGO, mci_seconds_show, NULL);
DEVICE_ATTR(ue_noinfo_count, S_IRUGO, mci_ue_noinfo_show, NULL);
DEVICE_ATTR(ce_noinfo_count, S_IRUGO, mci_ce_noinfo_show, NULL);
DEVICE_ATTR(ue_count, S_IRUGO, mci_ue_count_show, NULL);
DEVICE_ATTR(ce_count, S_IRUGO, mci_ce_count_show, NULL);
DEVICE_ATTR(max_location, S_IRUGO, mci_max_location_show, NULL);

/* memory scrubber attribute file */
DEVICE_ATTR(sdram_scrub_rate, S_IRUGO | S_IWUSR, mci_sdram_scrub_rate_show,
    mci_sdram_scrub_rate_store);

static struct attribute *mci_attrs[] = {
    &dev_attr_reset_counters.attr,
    &dev_attr_mc_name.attr,
    &dev_attr_size_mb.attr,
    &dev_attr_seconds_since_reset.attr,
    &dev_attr_ue_noinfo_count.attr,
    &dev_attr_ce_noinfo_count.attr,
    &dev_attr_ue_count.attr,
    &dev_attr_ce_count.attr,
    &dev_attr_sdram_scrub_rate.attr,
    &dev_attr_max_location.attr,
    NULL
};

static struct attribute_group mci_attr_grp = {
    .attrs  = mci_attrs,
};

static const struct attribute_group *mci_attr_groups[] = {
    &mci_attr_grp,
    NULL
};

static void mci_attr_release(struct device *dev)
{
    struct mem_ctl_info *mci = container_of(dev, struct mem_ctl_info, dev);

    edac_dbg(1, "Releasing csrow device %s\n", dev_name(dev));
    kfree(mci);
}

static struct device_type mci_attr_type = {
    .groups     = mci_attr_groups,
    .release    = mci_attr_release,
};

#ifdef CONFIG_EDAC_DEBUG
static struct dentry *edac_debugfs;

int __init edac_debugfs_init(void)
{
    edac_debugfs = debugfs_create_dir("edac", NULL);
    if (IS_ERR(edac_debugfs)) {
        edac_debugfs = NULL;
        return -ENOMEM;
    }
    return 0;
}

void __exit edac_debugfs_exit(void)
{
    debugfs_remove(edac_debugfs);
}

int edac_create_debug_nodes(struct mem_ctl_info *mci)
{
    struct dentry *d, *parent;
    char name[80];
    int i;

    if (!edac_debugfs)
        return -ENODEV;

    d = debugfs_create_dir(mci->dev.kobj.name, edac_debugfs);
    if (!d)
        return -ENOMEM;
    parent = d;

    for (i = 0; i < mci->n_layers; i++) {
        sprintf(name, "fake_inject_%s",
                 edac_layer_name[mci->layers[i].type]);
        d = debugfs_create_u8(name, S_IRUGO | S_IWUSR, parent,
                      &mci->fake_inject_layer[i]);
        if (!d)
            goto nomem;
    }

    d = debugfs_create_bool("fake_inject_ue", S_IRUGO | S_IWUSR, parent,
                &mci->fake_inject_ue);
    if (!d)
        goto nomem;

    d = debugfs_create_u16("fake_inject_count", S_IRUGO | S_IWUSR, parent,
                &mci->fake_inject_count);
    if (!d)
        goto nomem;

    d = debugfs_create_file("fake_inject", S_IWUSR, parent,
                &mci->dev,
                &debug_fake_inject_fops);
    if (!d)
        goto nomem;

    mci->debugfs = parent;
    return 0;
nomem:
    debugfs_remove(mci->debugfs);
    return -ENOMEM;
}
#endif

/*
 * Create a new Memory Controller kobject instance,
 *  mc<id> under the 'mc' directory
 *
 * Return:
 *  0   Success
 *  !0  Failure
 */
int edac_create_sysfs_mci_device(struct mem_ctl_info *mci)
{
    int i, err;

    /*
     * The memory controller needs its own bus, in order to avoid
     * namespace conflicts at /sys/bus/edac.
     */
    mci->bus.name = kasprintf(GFP_KERNEL, "mc%d", mci->mc_idx);
    if (!mci->bus.name)
        return -ENOMEM;
    edac_dbg(0, "creating bus %s\n", mci->bus.name);
    err = bus_register(&mci->bus);
    if (err < 0)
        return err;

    /* get the /sys/devices/system/edac subsys reference */
    mci->dev.type = &mci_attr_type;
    device_initialize(&mci->dev);

    mci->dev.parent = mci_pdev;
    mci->dev.bus = &mci->bus;
    dev_set_name(&mci->dev, "mc%d", mci->mc_idx);
    dev_set_drvdata(&mci->dev, mci);
    pm_runtime_forbid(&mci->dev);

    edac_dbg(0, "creating device %s\n", dev_name(&mci->dev));
    err = device_add(&mci->dev);
    if (err < 0) {
        bus_unregister(&mci->bus);
        kfree(mci->bus.name);
        return err;
    }

    /*
     * Create the dimm/rank devices
     */
    for (i = 0; i < mci->tot_dimms; i++) {
        struct dimm_info *dimm = mci->dimms[i];
        /* Only expose populated DIMMs */
        if (dimm->nr_pages == 0)
            continue;
#ifdef CONFIG_EDAC_DEBUG
        edac_dbg(1, "creating dimm%d, located at ", i);
        if (edac_debug_level >= 1) {
            int lay;
            for (lay = 0; lay < mci->n_layers; lay++)
                printk(KERN_CONT "%s %d ",
                    edac_layer_name[mci->layers[lay].type],
                    dimm->location[lay]);
            printk(KERN_CONT "\n");
        }
#endif
        err = edac_create_dimm_object(mci, dimm, i);
        if (err) {
            edac_dbg(1, "failure: create dimm %d obj\n", i);
            goto fail;
        }
    }

#ifdef CONFIG_EDAC_LEGACY_SYSFS
    err = edac_create_csrow_objects(mci);
    if (err < 0)
        goto fail;
#endif

#ifdef CONFIG_EDAC_DEBUG
    edac_create_debug_nodes(mci);
#endif
    return 0;

fail:
    for (i--; i >= 0; i--) {
        struct dimm_info *dimm = mci->dimms[i];
        if (dimm->nr_pages == 0)
            continue;
        put_device(&dimm->dev);
        device_del(&dimm->dev);
    }
    put_device(&mci->dev);
    device_del(&mci->dev);
    bus_unregister(&mci->bus);
    kfree(mci->bus.name);
    return err;
}

/*
 * remove a Memory Controller instance
 */
void edac_remove_sysfs_mci_device(struct mem_ctl_info *mci)
{
    int i;

    edac_dbg(0, "\n");

#ifdef CONFIG_EDAC_DEBUG
    debugfs_remove(mci->debugfs);
#endif
#ifdef CONFIG_EDAC_LEGACY_SYSFS
    edac_delete_csrow_objects(mci);
#endif

    for (i = 0; i < mci->tot_dimms; i++) {
        struct dimm_info *dimm = mci->dimms[i];
        if (dimm->nr_pages == 0)
            continue;
        edac_dbg(0, "removing device %s\n", dev_name(&dimm->dev));
        put_device(&dimm->dev);
        device_del(&dimm->dev);
    }
}

void edac_unregister_sysfs(struct mem_ctl_info *mci)
{
    edac_dbg(1, "Unregistering device %s\n", dev_name(&mci->dev));
    put_device(&mci->dev);
    device_del(&mci->dev);
    bus_unregister(&mci->bus);
    kfree(mci->bus.name);
}

static void mc_attr_release(struct device *dev)
{
    /*
     * There's no container structure here, as this is just the mci
     * parent device, used to create the /sys/devices/mc sysfs node.
     * So, there are no attributes on it.
     */
    edac_dbg(1, "Releasing device %s\n", dev_name(dev));
    kfree(dev);
}

static struct device_type mc_attr_type = {
    .release    = mc_attr_release,
};
/*
 * Init/exit code for the module. Basically, creates/removes /sys/class/rc
 */
int __init edac_mc_sysfs_init(void)
{
    struct bus_type *edac_subsys;
    int err;

    /* get the /sys/devices/system/edac subsys reference */
    edac_subsys = edac_get_sysfs_subsys();
    if (edac_subsys == NULL) {
        edac_dbg(1, "no edac_subsys\n");
        return -EINVAL;
    }

    mci_pdev = kzalloc(sizeof(*mci_pdev), GFP_KERNEL);

    mci_pdev->bus = edac_subsys;
    mci_pdev->type = &mc_attr_type;
    device_initialize(mci_pdev);
    dev_set_name(mci_pdev, "mc");

    err = device_add(mci_pdev);
    if (err < 0)
        return err;

    edac_dbg(0, "device %s created\n", dev_name(mci_pdev));

    return 0;
}

void __exit edac_mc_sysfs_exit(void)
{
    put_device(mci_pdev);
    device_del(mci_pdev);
    edac_put_sysfs_subsys();
}