/*
 * Intel MIC Platform Software Stack (MPSS)
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, 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.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Intel MIC Coprocessor State Management (COSM) Driver
 *
 */
#include <linux/slab.h>
#include "cosm_main.h"

/*
 * A state-to-string lookup table, for exposing a human readable state
 * via sysfs. Always keep in sync with enum cosm_states
 */
const char * const cosm_state_string[] = {
        [MIC_READY] = "ready",
        [MIC_BOOTING] = "booting",
        [MIC_ONLINE] = "online",
        [MIC_SHUTTING_DOWN] = "shutting_down",
        [MIC_RESETTING] = "resetting",
        [MIC_RESET_FAILED] = "reset_failed",
};

/*
 * A shutdown-status-to-string lookup table, for exposing a human
 * readable state via sysfs. Always keep in sync with enum cosm_shutdown_status
 */
const char * const cosm_shutdown_status_string[] = {
        [MIC_NOP] = "nop",
        [MIC_CRASHED] = "crashed",
        [MIC_HALTED] = "halted",
        [MIC_POWER_OFF] = "poweroff",
        [MIC_RESTART] = "restart",
};

void cosm_set_shutdown_status(struct cosm_device *cdev, u8 shutdown_status)
{
        dev_dbg(&cdev->dev, "Shutdown Status %s -> %s\n",
                cosm_shutdown_status_string[cdev->shutdown_status],
                cosm_shutdown_status_string[shutdown_status]);
        cdev->shutdown_status = shutdown_status;
}

void cosm_set_state(struct cosm_device *cdev, u8 state)
{
        dev_dbg(&cdev->dev, "State %s -> %s\n",
                cosm_state_string[cdev->state],
                cosm_state_string[state]);
        cdev->state = state;
        sysfs_notify_dirent(cdev->state_sysfs);
}

static ssize_t
family_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        return cdev->hw_ops->family(cdev, buf);
}
static DEVICE_ATTR_RO(family);

static ssize_t
stepping_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        return cdev->hw_ops->stepping(cdev, buf);
}
static DEVICE_ATTR_RO(stepping);

static ssize_t
state_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev || cdev->state >= MIC_LAST)
                return -EINVAL;

        return scnprintf(buf, PAGE_SIZE, "%s\n",
                cosm_state_string[cdev->state]);
}

static ssize_t
state_store(struct device *dev, struct device_attribute *attr,
            const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        int rc;

        if (!cdev)
                return -EINVAL;

        if (sysfs_streq(buf, "boot")) {
                rc = cosm_start(cdev);
                goto done;
        }
        if (sysfs_streq(buf, "reset")) {
                rc = cosm_reset(cdev);
                goto done;
        }

        if (sysfs_streq(buf, "shutdown")) {
                rc = cosm_shutdown(cdev);
                goto done;
        }
        rc = -EINVAL;
done:
        if (rc)
                count = rc;
        return count;
}
static DEVICE_ATTR_RW(state);

static ssize_t shutdown_status_show(struct device *dev,
                                    struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev || cdev->shutdown_status >= MIC_STATUS_LAST)
                return -EINVAL;

        return scnprintf(buf, PAGE_SIZE, "%s\n",
                cosm_shutdown_status_string[cdev->shutdown_status]);
}
static DEVICE_ATTR_RO(shutdown_status);

static ssize_t
heartbeat_enable_show(struct device *dev,
                      struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        return scnprintf(buf, PAGE_SIZE, "%d\n", cdev->sysfs_heartbeat_enable);
}

static ssize_t
heartbeat_enable_store(struct device *dev,
                       struct device_attribute *attr,
                       const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        int enable;
        int ret;

        if (!cdev)
                return -EINVAL;

        mutex_lock(&cdev->cosm_mutex);
        ret = kstrtoint(buf, 10, &enable);
        if (ret)
                goto unlock;

        cdev->sysfs_heartbeat_enable = enable;
        /* if state is not online, cdev->heartbeat_watchdog_enable is 0 */
        if (cdev->state == MIC_ONLINE)
                cdev->heartbeat_watchdog_enable = enable;
        ret = count;
unlock:
        mutex_unlock(&cdev->cosm_mutex);
        return ret;
}
static DEVICE_ATTR_RW(heartbeat_enable);

static ssize_t
cmdline_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        char *cmdline;

        if (!cdev)
                return -EINVAL;

        cmdline = cdev->cmdline;

        if (cmdline)
                return scnprintf(buf, PAGE_SIZE, "%s\n", cmdline);
        return 0;
}

static ssize_t
cmdline_store(struct device *dev, struct device_attribute *attr,
              const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        mutex_lock(&cdev->cosm_mutex);
        kfree(cdev->cmdline);

        cdev->cmdline = kmalloc(count + 1, GFP_KERNEL);
        if (!cdev->cmdline) {
                count = -ENOMEM;
                goto unlock;
        }

        strncpy(cdev->cmdline, buf, count);

        if (cdev->cmdline[count - 1] == '\n')
                cdev->cmdline[count - 1] = '\0';
        else
                cdev->cmdline[count] = '\0';
unlock:
        mutex_unlock(&cdev->cosm_mutex);
        return count;
}
static DEVICE_ATTR_RW(cmdline);

static ssize_t
firmware_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        char *firmware;

        if (!cdev)
                return -EINVAL;

        firmware = cdev->firmware;

        if (firmware)
                return scnprintf(buf, PAGE_SIZE, "%s\n", firmware);
        return 0;
}

static ssize_t
firmware_store(struct device *dev, struct device_attribute *attr,
               const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        mutex_lock(&cdev->cosm_mutex);
        kfree(cdev->firmware);

        cdev->firmware = kmalloc(count + 1, GFP_KERNEL);
        if (!cdev->firmware) {
                count = -ENOMEM;
                goto unlock;
        }
        strncpy(cdev->firmware, buf, count);

        if (cdev->firmware[count - 1] == '\n')
                cdev->firmware[count - 1] = '\0';
        else
                cdev->firmware[count] = '\0';
unlock:
        mutex_unlock(&cdev->cosm_mutex);
        return count;
}
static DEVICE_ATTR_RW(firmware);

static ssize_t
ramdisk_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        char *ramdisk;

        if (!cdev)
                return -EINVAL;

        ramdisk = cdev->ramdisk;

        if (ramdisk)
                return scnprintf(buf, PAGE_SIZE, "%s\n", ramdisk);
        return 0;
}

static ssize_t
ramdisk_store(struct device *dev, struct device_attribute *attr,
              const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        mutex_lock(&cdev->cosm_mutex);
        kfree(cdev->ramdisk);

        cdev->ramdisk = kmalloc(count + 1, GFP_KERNEL);
        if (!cdev->ramdisk) {
                count = -ENOMEM;
                goto unlock;
        }

        strncpy(cdev->ramdisk, buf, count);

        if (cdev->ramdisk[count - 1] == '\n')
                cdev->ramdisk[count - 1] = '\0';
        else
                cdev->ramdisk[count] = '\0';
unlock:
        mutex_unlock(&cdev->cosm_mutex);
        return count;
}
static DEVICE_ATTR_RW(ramdisk);

static ssize_t
bootmode_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        char *bootmode;

        if (!cdev)
                return -EINVAL;

        bootmode = cdev->bootmode;

        if (bootmode)
                return scnprintf(buf, PAGE_SIZE, "%s\n", bootmode);
        return 0;
}

static ssize_t
bootmode_store(struct device *dev, struct device_attribute *attr,
               const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        if (!sysfs_streq(buf, "linux") && !sysfs_streq(buf, "flash"))
                return -EINVAL;

        mutex_lock(&cdev->cosm_mutex);
        kfree(cdev->bootmode);

        cdev->bootmode = kmalloc(count + 1, GFP_KERNEL);
        if (!cdev->bootmode) {
                count = -ENOMEM;
                goto unlock;
        }

        strncpy(cdev->bootmode, buf, count);

        if (cdev->bootmode[count - 1] == '\n')
                cdev->bootmode[count - 1] = '\0';
        else
                cdev->bootmode[count] = '\0';
unlock:
        mutex_unlock(&cdev->cosm_mutex);
        return count;
}
static DEVICE_ATTR_RW(bootmode);

static ssize_t
log_buf_addr_show(struct device *dev, struct device_attribute *attr,
                  char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        return scnprintf(buf, PAGE_SIZE, "%p\n", cdev->log_buf_addr);
}

static ssize_t
log_buf_addr_store(struct device *dev, struct device_attribute *attr,
                   const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        int ret;
        unsigned long addr;

        if (!cdev)
                return -EINVAL;

        ret = kstrtoul(buf, 16, &addr);
        if (ret)
                goto exit;

        cdev->log_buf_addr = (void *)addr;
        ret = count;
exit:
        return ret;
}
static DEVICE_ATTR_RW(log_buf_addr);

static ssize_t
log_buf_len_show(struct device *dev, struct device_attribute *attr,
                 char *buf)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);

        if (!cdev)
                return -EINVAL;

        return scnprintf(buf, PAGE_SIZE, "%p\n", cdev->log_buf_len);
}

static ssize_t
log_buf_len_store(struct device *dev, struct device_attribute *attr,
                  const char *buf, size_t count)
{
        struct cosm_device *cdev = dev_get_drvdata(dev);
        int ret;
        unsigned long addr;

        if (!cdev)
                return -EINVAL;

        ret = kstrtoul(buf, 16, &addr);
        if (ret)
                goto exit;

        cdev->log_buf_len = (int *)addr;
        ret = count;
exit:
        return ret;
}
static DEVICE_ATTR_RW(log_buf_len);

static struct attribute *cosm_default_attrs[] = {
        &dev_attr_family.attr,
        &dev_attr_stepping.attr,
        &dev_attr_state.attr,
        &dev_attr_shutdown_status.attr,
        &dev_attr_heartbeat_enable.attr,
        &dev_attr_cmdline.attr,
        &dev_attr_firmware.attr,
        &dev_attr_ramdisk.attr,
        &dev_attr_bootmode.attr,
        &dev_attr_log_buf_addr.attr,
        &dev_attr_log_buf_len.attr,

        NULL
};

ATTRIBUTE_GROUPS(cosm_default);

void cosm_sysfs_init(struct cosm_device *cdev)
{
        cdev->attr_group = cosm_default_groups;
}