// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2021 Intel Corporation. All rights rsvd. */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/debugfs.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <uapi/linux/idxd.h>
#include "idxd.h"
#include "registers.h"

static struct dentry *idxd_debugfs_dir;

static void dump_event_entry(struct idxd_device *idxd, struct seq_file *s,
                             u16 index, int *count, bool processed)
{
        struct idxd_evl *evl = idxd->evl;
        struct dsa_evl_entry *entry;
        struct dsa_completion_record *cr;
        u64 *raw;
        int i;
        int evl_strides = evl_ent_size(idxd) / sizeof(u64);

        entry = (struct dsa_evl_entry *)evl->log + index;

        if (!entry->e.desc_valid)
                return;

        seq_printf(s, "Event Log entry %d (real index %u) processed: %u\n",
                   *count, index, processed);

        seq_printf(s, "desc valid %u wq idx valid %u\n"
                   "batch %u fault rw %u priv %u error 0x%x\n"
                   "wq idx %u op %#x pasid %u batch idx %u\n"
                   "fault addr %#llx\n",
                   entry->e.desc_valid, entry->e.wq_idx_valid,
                   entry->e.batch, entry->e.fault_rw, entry->e.priv,
                   entry->e.error, entry->e.wq_idx, entry->e.operation,
                   entry->e.pasid, entry->e.batch_idx, entry->e.fault_addr);

        cr = &entry->cr;
        seq_printf(s, "status %#x result %#x fault_info %#x bytes_completed %u\n"
                   "fault addr %#llx inv flags %#x\n\n",
                   cr->status, cr->result, cr->fault_info, cr->bytes_completed,
                   cr->fault_addr, cr->invalid_flags);

        raw = (u64 *)entry;

        for (i = 0; i < evl_strides; i++)
                seq_printf(s, "entry[%d] = %#llx\n", i, raw[i]);

        seq_puts(s, "\n");
        *count += 1;
}

static int debugfs_evl_show(struct seq_file *s, void *d)
{
        struct idxd_device *idxd = s->private;
        struct idxd_evl *evl = idxd->evl;
        union evl_status_reg evl_status;
        u16 h, t, evl_size, i;
        int count = 0;
        bool processed = true;

        if (!evl || !evl->log)
                return 0;

        mutex_lock(&evl->lock);

        evl_status.bits = ioread64(idxd->reg_base + IDXD_EVLSTATUS_OFFSET);
        t = evl_status.tail;
        h = evl_status.head;
        evl_size = evl->size;

        seq_printf(s, "Event Log head %u tail %u interrupt pending %u\n\n",
                   evl_status.head, evl_status.tail, evl_status.int_pending);

        i = t;
        while (1) {
                i = (i + 1) % evl_size;
                if (i == t)
                        break;

                if (processed && i == h)
                        processed = false;
                dump_event_entry(idxd, s, i, &count, processed);
        }

        mutex_unlock(&evl->lock);
        return 0;
}

DEFINE_SHOW_ATTRIBUTE(debugfs_evl);

int idxd_device_init_debugfs(struct idxd_device *idxd)
{
        if (IS_ERR_OR_NULL(idxd_debugfs_dir))
                return 0;

        idxd->dbgfs_dir = debugfs_create_dir(dev_name(idxd_confdev(idxd)), idxd_debugfs_dir);
        if (IS_ERR(idxd->dbgfs_dir))
                return PTR_ERR(idxd->dbgfs_dir);

        if (idxd->evl) {
                idxd->dbgfs_evl_file = debugfs_create_file("event_log", 0400,
                                                           idxd->dbgfs_dir, idxd,
                                                           &debugfs_evl_fops);
                if (IS_ERR(idxd->dbgfs_evl_file)) {
                        debugfs_remove_recursive(idxd->dbgfs_dir);
                        idxd->dbgfs_dir = NULL;
                        return PTR_ERR(idxd->dbgfs_evl_file);
                }
        }

        return 0;
}

void idxd_device_remove_debugfs(struct idxd_device *idxd)
{
        debugfs_remove_recursive(idxd->dbgfs_dir);
}

int idxd_init_debugfs(void)
{
        if (!debugfs_initialized())
                return 0;

        idxd_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
        if (IS_ERR(idxd_debugfs_dir))
                return  PTR_ERR(idxd_debugfs_dir);
        return 0;
}

void idxd_remove_debugfs(void)
{
        debugfs_remove_recursive(idxd_debugfs_dir);
}