// SPDX-License-Identifier: GPL-2.0-only
/*
 * Linux network driver for QLogic BR-series Converged Network Adapter.
 */
/*
 * Copyright (c) 2005-2014 Brocade Communications Systems, Inc.
 * Copyright (c) 2014-2015 QLogic Corporation
 * All rights reserved
 * www.qlogic.com
 */

#include <linux/debugfs.h>
#include <linux/module.h>
#include "bnad.h"

/*
 * BNA debufs interface
 *
 * To access the interface, debugfs file system should be mounted
 * if not already mounted using:
 *      mount -t debugfs none /sys/kernel/debug
 *
 * BNA Hierarchy:
 *      - bna/pci_dev:<pci_name>
 * where the pci_name corresponds to the one under /sys/bus/pci/drivers/bna
 *
 * Debugging service available per pci_dev:
 *      fwtrc:  To collect current firmware trace.
 *      fwsave: To collect last saved fw trace as a result of firmware crash.
 *      regwr:  To write one word to chip register
 *      regrd:  To read one or more words from chip register.
 */

struct bnad_debug_info {
        char *debug_buffer;
        void *i_private;
        int buffer_len;
};

static int
bnad_debugfs_open_fwtrc(struct inode *inode, struct file *file)
{
        struct bnad *bnad = inode->i_private;
        struct bnad_debug_info *fw_debug;
        unsigned long flags;
        int rc;

        fw_debug = kzalloc_obj(struct bnad_debug_info);
        if (!fw_debug)
                return -ENOMEM;

        fw_debug->buffer_len = BNA_DBG_FWTRC_LEN;

        fw_debug->debug_buffer = kzalloc(fw_debug->buffer_len, GFP_KERNEL);
        if (!fw_debug->debug_buffer) {
                kfree(fw_debug);
                fw_debug = NULL;
                return -ENOMEM;
        }

        spin_lock_irqsave(&bnad->bna_lock, flags);
        rc = bfa_nw_ioc_debug_fwtrc(&bnad->bna.ioceth.ioc,
                        fw_debug->debug_buffer,
                        &fw_debug->buffer_len);
        spin_unlock_irqrestore(&bnad->bna_lock, flags);
        if (rc != BFA_STATUS_OK) {
                kfree(fw_debug->debug_buffer);
                fw_debug->debug_buffer = NULL;
                kfree(fw_debug);
                fw_debug = NULL;
                netdev_warn(bnad->netdev, "failed to collect fwtrc\n");
                return -ENOMEM;
        }

        file->private_data = fw_debug;

        return 0;
}

static int
bnad_debugfs_open_fwsave(struct inode *inode, struct file *file)
{
        struct bnad *bnad = inode->i_private;
        struct bnad_debug_info *fw_debug;
        unsigned long flags;
        int rc;

        fw_debug = kzalloc_obj(struct bnad_debug_info);
        if (!fw_debug)
                return -ENOMEM;

        fw_debug->buffer_len = BNA_DBG_FWTRC_LEN;

        fw_debug->debug_buffer = kzalloc(fw_debug->buffer_len, GFP_KERNEL);
        if (!fw_debug->debug_buffer) {
                kfree(fw_debug);
                fw_debug = NULL;
                return -ENOMEM;
        }

        spin_lock_irqsave(&bnad->bna_lock, flags);
        rc = bfa_nw_ioc_debug_fwsave(&bnad->bna.ioceth.ioc,
                        fw_debug->debug_buffer,
                        &fw_debug->buffer_len);
        spin_unlock_irqrestore(&bnad->bna_lock, flags);
        if (rc != BFA_STATUS_OK && rc != BFA_STATUS_ENOFSAVE) {
                kfree(fw_debug->debug_buffer);
                fw_debug->debug_buffer = NULL;
                kfree(fw_debug);
                fw_debug = NULL;
                netdev_warn(bnad->netdev, "failed to collect fwsave\n");
                return -ENOMEM;
        }

        file->private_data = fw_debug;

        return 0;
}

static int
bnad_debugfs_open_reg(struct inode *inode, struct file *file)
{
        struct bnad_debug_info *reg_debug;

        reg_debug = kzalloc_obj(struct bnad_debug_info);
        if (!reg_debug)
                return -ENOMEM;

        reg_debug->i_private = inode->i_private;

        file->private_data = reg_debug;

        return 0;
}

static int
bnad_get_debug_drvinfo(struct bnad *bnad, void *buffer, u32 len)
{
        struct bnad_drvinfo *drvinfo = (struct bnad_drvinfo *) buffer;
        struct bnad_iocmd_comp fcomp;
        unsigned long flags = 0;
        int ret = BFA_STATUS_FAILED;

        /* Get IOC info */
        spin_lock_irqsave(&bnad->bna_lock, flags);
        bfa_nw_ioc_get_attr(&bnad->bna.ioceth.ioc, &drvinfo->ioc_attr);
        spin_unlock_irqrestore(&bnad->bna_lock, flags);

        /* Retrieve CEE related info */
        fcomp.bnad = bnad;
        fcomp.comp_status = 0;
        init_completion(&fcomp.comp);
        spin_lock_irqsave(&bnad->bna_lock, flags);
        ret = bfa_nw_cee_get_attr(&bnad->bna.cee, &drvinfo->cee_attr,
                                bnad_cb_completion, &fcomp);
        if (ret != BFA_STATUS_OK) {
                spin_unlock_irqrestore(&bnad->bna_lock, flags);
                goto out;
        }
        spin_unlock_irqrestore(&bnad->bna_lock, flags);
        wait_for_completion(&fcomp.comp);
        drvinfo->cee_status = fcomp.comp_status;

        /* Retrieve flash partition info */
        fcomp.comp_status = 0;
        reinit_completion(&fcomp.comp);
        spin_lock_irqsave(&bnad->bna_lock, flags);
        ret = bfa_nw_flash_get_attr(&bnad->bna.flash, &drvinfo->flash_attr,
                                bnad_cb_completion, &fcomp);
        if (ret != BFA_STATUS_OK) {
                spin_unlock_irqrestore(&bnad->bna_lock, flags);
                goto out;
        }
        spin_unlock_irqrestore(&bnad->bna_lock, flags);
        wait_for_completion(&fcomp.comp);
        drvinfo->flash_status = fcomp.comp_status;
out:
        return ret;
}

static int
bnad_debugfs_open_drvinfo(struct inode *inode, struct file *file)
{
        struct bnad *bnad = inode->i_private;
        struct bnad_debug_info *drv_info;
        int rc;

        drv_info = kzalloc_obj(struct bnad_debug_info);
        if (!drv_info)
                return -ENOMEM;

        drv_info->buffer_len = sizeof(struct bnad_drvinfo);

        drv_info->debug_buffer = kzalloc(drv_info->buffer_len, GFP_KERNEL);
        if (!drv_info->debug_buffer) {
                kfree(drv_info);
                drv_info = NULL;
                return -ENOMEM;
        }

        mutex_lock(&bnad->conf_mutex);
        rc = bnad_get_debug_drvinfo(bnad, drv_info->debug_buffer,
                                drv_info->buffer_len);
        mutex_unlock(&bnad->conf_mutex);
        if (rc != BFA_STATUS_OK) {
                kfree(drv_info->debug_buffer);
                drv_info->debug_buffer = NULL;
                kfree(drv_info);
                drv_info = NULL;
                netdev_warn(bnad->netdev, "failed to collect drvinfo\n");
                return -ENOMEM;
        }

        file->private_data = drv_info;

        return 0;
}

/* Changes the current file position */
static loff_t
bnad_debugfs_lseek(struct file *file, loff_t offset, int orig)
{
        struct bnad_debug_info *debug = file->private_data;

        if (!debug)
                return -EINVAL;

        return fixed_size_llseek(file, offset, orig, debug->buffer_len);
}

static ssize_t
bnad_debugfs_read(struct file *file, char __user *buf,
                  size_t nbytes, loff_t *pos)
{
        struct bnad_debug_info *debug = file->private_data;

        if (!debug || !debug->debug_buffer)
                return 0;

        return simple_read_from_buffer(buf, nbytes, pos,
                                debug->debug_buffer, debug->buffer_len);
}

#define BFA_REG_CT_ADDRSZ       (0x40000)
#define BFA_REG_CB_ADDRSZ       (0x20000)
#define BFA_REG_ADDRSZ(__ioc)   \
        ((u32)(bfa_asic_id_ctc(bfa_ioc_devid(__ioc)) ?  \
         BFA_REG_CT_ADDRSZ : BFA_REG_CB_ADDRSZ))
#define BFA_REG_ADDRMSK(__ioc)  (BFA_REG_ADDRSZ(__ioc) - 1)

/*
 * Function to check if the register offset passed is valid.
 */
static int
bna_reg_offset_check(struct bfa_ioc *ioc, u32 offset, u32 len)
{
        u8 area;

        /* check [16:15] */
        area = (offset >> 15) & 0x7;
        if (area == 0) {
                /* PCIe core register */
                if (offset + (len << 2) > 0x8000)       /* 8k dwords or 32KB */
                        return BFA_STATUS_EINVAL;
        } else if (area == 0x1) {
                /* CB 32 KB memory page */
                if (offset + (len << 2) > 0x10000)      /* 8k dwords or 32KB */
                        return BFA_STATUS_EINVAL;
        } else {
                /* CB register space 64KB */
                if (offset + (len << 2) > BFA_REG_ADDRMSK(ioc))
                        return BFA_STATUS_EINVAL;
        }
        return BFA_STATUS_OK;
}

static ssize_t
bnad_debugfs_read_regrd(struct file *file, char __user *buf,
                        size_t nbytes, loff_t *pos)
{
        struct bnad_debug_info *regrd_debug = file->private_data;
        struct bnad *bnad = (struct bnad *)regrd_debug->i_private;
        ssize_t rc;

        if (!bnad->regdata)
                return 0;

        rc = simple_read_from_buffer(buf, nbytes, pos,
                        bnad->regdata, bnad->reglen);

        if ((*pos + nbytes) >= bnad->reglen) {
                kfree(bnad->regdata);
                bnad->regdata = NULL;
                bnad->reglen = 0;
        }

        return rc;
}

static ssize_t
bnad_debugfs_write_regrd(struct file *file, const char __user *buf,
                size_t nbytes, loff_t *ppos)
{
        struct bnad_debug_info *regrd_debug = file->private_data;
        struct bnad *bnad = (struct bnad *)regrd_debug->i_private;
        struct bfa_ioc *ioc = &bnad->bna.ioceth.ioc;
        int rc, i;
        u32 addr, len;
        u32 *regbuf;
        void __iomem *rb, *reg_addr;
        unsigned long flags;
        void *kern_buf;

        /* Copy the user space buf */
        kern_buf = memdup_user_nul(buf, nbytes);
        if (IS_ERR(kern_buf))
                return PTR_ERR(kern_buf);

        rc = sscanf(kern_buf, "%x:%x", &addr, &len);
        if (rc < 2 || len > UINT_MAX >> 2) {
                netdev_warn(bnad->netdev, "failed to read user buffer\n");
                kfree(kern_buf);
                return -EINVAL;
        }

        kfree(kern_buf);
        kfree(bnad->regdata);
        bnad->reglen = 0;

        bnad->regdata = kzalloc(len << 2, GFP_KERNEL);
        if (!bnad->regdata)
                return -ENOMEM;

        bnad->reglen = len << 2;
        rb = bfa_ioc_bar0(ioc);
        addr &= BFA_REG_ADDRMSK(ioc);

        /* offset and len sanity check */
        rc = bna_reg_offset_check(ioc, addr, len);
        if (rc) {
                netdev_warn(bnad->netdev, "failed reg offset check\n");
                kfree(bnad->regdata);
                bnad->regdata = NULL;
                bnad->reglen = 0;
                return -EINVAL;
        }

        reg_addr = rb + addr;
        regbuf =  (u32 *)bnad->regdata;
        spin_lock_irqsave(&bnad->bna_lock, flags);
        for (i = 0; i < len; i++) {
                *regbuf = readl(reg_addr);
                regbuf++;
                reg_addr += sizeof(u32);
        }
        spin_unlock_irqrestore(&bnad->bna_lock, flags);

        return nbytes;
}

static ssize_t
bnad_debugfs_write_regwr(struct file *file, const char __user *buf,
                size_t nbytes, loff_t *ppos)
{
        struct bnad_debug_info *debug = file->private_data;
        struct bnad *bnad = (struct bnad *)debug->i_private;
        struct bfa_ioc *ioc = &bnad->bna.ioceth.ioc;
        int rc;
        u32 addr, val;
        void __iomem *reg_addr;
        unsigned long flags;
        void *kern_buf;

        /* Copy the user space buf */
        kern_buf = memdup_user_nul(buf, nbytes);
        if (IS_ERR(kern_buf))
                return PTR_ERR(kern_buf);

        rc = sscanf(kern_buf, "%x:%x", &addr, &val);
        if (rc < 2) {
                netdev_warn(bnad->netdev, "failed to read user buffer\n");
                kfree(kern_buf);
                return -EINVAL;
        }
        kfree(kern_buf);

        addr &= BFA_REG_ADDRMSK(ioc); /* offset only 17 bit and word align */

        /* offset and len sanity check */
        rc = bna_reg_offset_check(ioc, addr, 1);
        if (rc) {
                netdev_warn(bnad->netdev, "failed reg offset check\n");
                return -EINVAL;
        }

        reg_addr = (bfa_ioc_bar0(ioc)) + addr;
        spin_lock_irqsave(&bnad->bna_lock, flags);
        writel(val, reg_addr);
        spin_unlock_irqrestore(&bnad->bna_lock, flags);

        return nbytes;
}

static int
bnad_debugfs_release(struct inode *inode, struct file *file)
{
        struct bnad_debug_info *debug = file->private_data;

        if (!debug)
                return 0;

        file->private_data = NULL;
        kfree(debug);
        return 0;
}

static int
bnad_debugfs_buffer_release(struct inode *inode, struct file *file)
{
        struct bnad_debug_info *debug = file->private_data;

        if (!debug)
                return 0;

        kfree(debug->debug_buffer);

        file->private_data = NULL;
        kfree(debug);
        debug = NULL;
        return 0;
}

static const struct file_operations bnad_debugfs_op_fwtrc = {
        .owner          =       THIS_MODULE,
        .open           =       bnad_debugfs_open_fwtrc,
        .llseek         =       bnad_debugfs_lseek,
        .read           =       bnad_debugfs_read,
        .release        =       bnad_debugfs_buffer_release,
};

static const struct file_operations bnad_debugfs_op_fwsave = {
        .owner          =       THIS_MODULE,
        .open           =       bnad_debugfs_open_fwsave,
        .llseek         =       bnad_debugfs_lseek,
        .read           =       bnad_debugfs_read,
        .release        =       bnad_debugfs_buffer_release,
};

static const struct file_operations bnad_debugfs_op_regrd = {
        .owner          =       THIS_MODULE,
        .open           =       bnad_debugfs_open_reg,
        .llseek         =       bnad_debugfs_lseek,
        .read           =       bnad_debugfs_read_regrd,
        .write          =       bnad_debugfs_write_regrd,
        .release        =       bnad_debugfs_release,
};

static const struct file_operations bnad_debugfs_op_regwr = {
        .owner          =       THIS_MODULE,
        .open           =       bnad_debugfs_open_reg,
        .llseek         =       bnad_debugfs_lseek,
        .write          =       bnad_debugfs_write_regwr,
        .release        =       bnad_debugfs_release,
};

static const struct file_operations bnad_debugfs_op_drvinfo = {
        .owner          =       THIS_MODULE,
        .open           =       bnad_debugfs_open_drvinfo,
        .llseek         =       bnad_debugfs_lseek,
        .read           =       bnad_debugfs_read,
        .release        =       bnad_debugfs_buffer_release,
};

struct bnad_debugfs_entry {
        const char *name;
        umode_t  mode;
        const struct file_operations *fops;
};

static const struct bnad_debugfs_entry bnad_debugfs_files[] = {
        { "fwtrc",  S_IFREG | 0444, &bnad_debugfs_op_fwtrc, },
        { "fwsave", S_IFREG | 0444, &bnad_debugfs_op_fwsave, },
        { "regrd",  S_IFREG | 0644, &bnad_debugfs_op_regrd, },
        { "regwr",  S_IFREG | 0200, &bnad_debugfs_op_regwr, },
        { "drvinfo", S_IFREG | 0444, &bnad_debugfs_op_drvinfo, },
};

static struct dentry *bna_debugfs_root;
static atomic_t bna_debugfs_port_count;

/* Initialize debugfs interface for BNA */
void
bnad_debugfs_init(struct bnad *bnad)
{
        const struct bnad_debugfs_entry *file;
        char name[64];
        int i;

        /* Setup the BNA debugfs root directory*/
        if (!bna_debugfs_root) {
                bna_debugfs_root = debugfs_create_dir("bna", NULL);
                atomic_set(&bna_debugfs_port_count, 0);
        }

        /* Setup the pci_dev debugfs directory for the port */
        snprintf(name, sizeof(name), "pci_dev:%s", pci_name(bnad->pcidev));
        if (!bnad->port_debugfs_root) {
                bnad->port_debugfs_root =
                        debugfs_create_dir(name, bna_debugfs_root);

                atomic_inc(&bna_debugfs_port_count);

                for (i = 0; i < ARRAY_SIZE(bnad_debugfs_files); i++) {
                        file = &bnad_debugfs_files[i];
                        debugfs_create_file(file->name,
                                            file->mode,
                                            bnad->port_debugfs_root,
                                            bnad,
                                            file->fops);
                }
        }
}

/* Uninitialize debugfs interface for BNA */
void
bnad_debugfs_uninit(struct bnad *bnad)
{
        /* Remove the pci_dev debugfs directory for the port */
        if (bnad->port_debugfs_root) {
                debugfs_remove(bnad->port_debugfs_root);
                bnad->port_debugfs_root = NULL;
                atomic_dec(&bna_debugfs_port_count);
        }

        /* Remove the BNA debugfs root directory */
        if (atomic_read(&bna_debugfs_port_count) == 0) {
                debugfs_remove(bna_debugfs_root);
                bna_debugfs_root = NULL;
        }
}