/**
 * IBM Accelerator Family 'GenWQE'
 *
 * (C) Copyright IBM Corp. 2013
 *
 * Author: Frank Haverkamp <haver@linux.vnet.ibm.com>
 * Author: Joerg-Stephan Vogt <jsvogt@de.ibm.com>
 * Author: Michael Jung <mijung@gmx.net>
 * Author: Michael Ruettger <michael@ibmra.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (version 2 only)
 * 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.
 */

/*
 * Sysfs interfaces for the GenWQE card. There are attributes to query
 * the version of the bitstream as well as some for the driver. For
 * debugging, please also see the debugfs interfaces of this driver.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/sysfs.h>
#include <linux/ctype.h>
#include <linux/device.h>

#include "card_base.h"
#include "card_ddcb.h"

static const char * const genwqe_types[] = {
        [GENWQE_TYPE_ALTERA_230] = "GenWQE4-230",
        [GENWQE_TYPE_ALTERA_530] = "GenWQE4-530",
        [GENWQE_TYPE_ALTERA_A4]  = "GenWQE5-A4",
        [GENWQE_TYPE_ALTERA_A7]  = "GenWQE5-A7",
};

static ssize_t status_show(struct device *dev, struct device_attribute *attr,
                           char *buf)
{
        struct genwqe_dev *cd = dev_get_drvdata(dev);
        const char *cs[GENWQE_CARD_STATE_MAX] = { "unused", "used", "error" };

        return sprintf(buf, "%s\n", cs[cd->card_state]);
}
static DEVICE_ATTR_RO(status);

static ssize_t appid_show(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        char app_name[5];
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        genwqe_read_app_id(cd, app_name, sizeof(app_name));
        return sprintf(buf, "%s\n", app_name);
}
static DEVICE_ATTR_RO(appid);

static ssize_t version_show(struct device *dev, struct device_attribute *attr,
                            char *buf)
{
        u64 slu_id, app_id;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        slu_id = __genwqe_readq(cd, IO_SLU_UNITCFG);
        app_id = __genwqe_readq(cd, IO_APP_UNITCFG);

        return sprintf(buf, "%016llx.%016llx\n", slu_id, app_id);
}
static DEVICE_ATTR_RO(version);

static ssize_t type_show(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        u8 card_type;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        card_type = genwqe_card_type(cd);
        return sprintf(buf, "%s\n", (card_type >= ARRAY_SIZE(genwqe_types)) ?
                       "invalid" : genwqe_types[card_type]);
}
static DEVICE_ATTR_RO(type);

static ssize_t tempsens_show(struct device *dev, struct device_attribute *attr,
                             char *buf)
{
        u64 tempsens;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        tempsens = __genwqe_readq(cd, IO_SLU_TEMPERATURE_SENSOR);
        return sprintf(buf, "%016llx\n", tempsens);
}
static DEVICE_ATTR_RO(tempsens);

static ssize_t freerunning_timer_show(struct device *dev,
                                      struct device_attribute *attr,
                                      char *buf)
{
        u64 t;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        t = __genwqe_readq(cd, IO_SLC_FREE_RUNNING_TIMER);
        return sprintf(buf, "%016llx\n", t);
}
static DEVICE_ATTR_RO(freerunning_timer);

static ssize_t queue_working_time_show(struct device *dev,
                                       struct device_attribute *attr,
                                       char *buf)
{
        u64 t;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        t = __genwqe_readq(cd, IO_SLC_QUEUE_WTIME);
        return sprintf(buf, "%016llx\n", t);
}
static DEVICE_ATTR_RO(queue_working_time);

static ssize_t base_clock_show(struct device *dev,
                               struct device_attribute *attr,
                               char *buf)
{
        u64 base_clock;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        base_clock = genwqe_base_clock_frequency(cd);
        return sprintf(buf, "%lld\n", base_clock);
}
static DEVICE_ATTR_RO(base_clock);

/**
 * curr_bitstream_show() - Show the current bitstream id
 *
 * There is a bug in some old versions of the CPLD which selects the
 * bitstream, which causes the IO_SLU_BITSTREAM register to report
 * unreliable data in very rare cases. This makes this sysfs
 * unreliable up to the point were a new CPLD version is being used.
 *
 * Unfortunately there is no automatic way yet to query the CPLD
 * version, such that you need to manually ensure via programming
 * tools that you have a recent version of the CPLD software.
 *
 * The proposed circumvention is to use a special recovery bitstream
 * on the backup partition (0) to identify problems while loading the
 * image.
 */
static ssize_t curr_bitstream_show(struct device *dev,
                                   struct device_attribute *attr, char *buf)
{
        int curr_bitstream;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        curr_bitstream = __genwqe_readq(cd, IO_SLU_BITSTREAM) & 0x1;
        return sprintf(buf, "%d\n", curr_bitstream);
}
static DEVICE_ATTR_RO(curr_bitstream);

/**
 * next_bitstream_show() - Show the next activated bitstream
 *
 * IO_SLC_CFGREG_SOFTRESET: This register can only be accessed by the PF.
 */
static ssize_t next_bitstream_show(struct device *dev,
                                   struct device_attribute *attr, char *buf)
{
        int next_bitstream;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        switch ((cd->softreset & 0xc) >> 2) {
        case 0x2:
                next_bitstream =  0;
                break;
        case 0x3:
                next_bitstream =  1;
                break;
        default:
                next_bitstream = -1;
                break;          /* error */
        }
        return sprintf(buf, "%d\n", next_bitstream);
}

static ssize_t next_bitstream_store(struct device *dev,
                                    struct device_attribute *attr,
                                    const char *buf, size_t count)
{
        int partition;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        if (kstrtoint(buf, 0, &partition) < 0)
                return -EINVAL;

        switch (partition) {
        case 0x0:
                cd->softreset = 0x78;
                break;
        case 0x1:
                cd->softreset = 0x7c;
                break;
        default:
                return -EINVAL;
        }

        __genwqe_writeq(cd, IO_SLC_CFGREG_SOFTRESET, cd->softreset);
        return count;
}
static DEVICE_ATTR_RW(next_bitstream);

static ssize_t reload_bitstream_store(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        int reload;
        struct genwqe_dev *cd = dev_get_drvdata(dev);

        if (kstrtoint(buf, 0, &reload) < 0)
                return -EINVAL;

        if (reload == 0x1) {
                if (cd->card_state == GENWQE_CARD_UNUSED ||
                    cd->card_state == GENWQE_CARD_USED)
                        cd->card_state = GENWQE_CARD_RELOAD_BITSTREAM;
                else
                        return -EIO;
        } else {
                return -EINVAL;
        }

        return count;
}
static DEVICE_ATTR_WO(reload_bitstream);

/*
 * Create device_attribute structures / params: name, mode, show, store
 * additional flag if valid in VF
 */
static struct attribute *genwqe_attributes[] = {
        &dev_attr_tempsens.attr,
        &dev_attr_next_bitstream.attr,
        &dev_attr_curr_bitstream.attr,
        &dev_attr_base_clock.attr,
        &dev_attr_type.attr,
        &dev_attr_version.attr,
        &dev_attr_appid.attr,
        &dev_attr_status.attr,
        &dev_attr_freerunning_timer.attr,
        &dev_attr_queue_working_time.attr,
        &dev_attr_reload_bitstream.attr,
        NULL,
};

static struct attribute *genwqe_normal_attributes[] = {
        &dev_attr_type.attr,
        &dev_attr_version.attr,
        &dev_attr_appid.attr,
        &dev_attr_status.attr,
        &dev_attr_freerunning_timer.attr,
        &dev_attr_queue_working_time.attr,
        NULL,
};

/**
 * genwqe_is_visible() - Determine if sysfs attribute should be visible or not
 *
 * VFs have restricted mmio capabilities, so not all sysfs entries
 * are allowed in VFs.
 */
static umode_t genwqe_is_visible(struct kobject *kobj,
                                 struct attribute *attr, int n)
{
        unsigned int j;
        struct device *dev = kobj_to_dev(kobj);
        struct genwqe_dev *cd = dev_get_drvdata(dev);
        umode_t mode = attr->mode;

        if (genwqe_is_privileged(cd))
                return mode;

        for (j = 0; genwqe_normal_attributes[j] != NULL;  j++)
                if (genwqe_normal_attributes[j] == attr)
                        return mode;

        return 0;
}

static struct attribute_group genwqe_attribute_group = {
        .is_visible = genwqe_is_visible,
        .attrs      = genwqe_attributes,
};

const struct attribute_group *genwqe_attribute_groups[] = {
        &genwqe_attribute_group,
        NULL,
};