// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Cryptographic Coprocessor (CCP) driver
 *
 * Copyright (C) 2017 Advanced Micro Devices, Inc.
 *
 * Author: Gary R Hook <gary.hook@amd.com>
 */

#include <linux/debugfs.h>
#include <linux/ccp.h>

#include "ccp-dev.h"

/* DebugFS helpers */
#define OBUFP           (obuf + oboff)
#define OBUFLEN         512
#define OBUFSPC         (OBUFLEN - oboff)
#define OSCNPRINTF(fmt, ...) \
                scnprintf(OBUFP, OBUFSPC, fmt, ## __VA_ARGS__)

#define BUFLEN  63

#define RI_VERSION_NUM  0x0000003F
#define RI_AES_PRESENT  0x00000040
#define RI_3DES_PRESENT 0x00000080
#define RI_SHA_PRESENT  0x00000100
#define RI_RSA_PRESENT  0x00000200
#define RI_ECC_PRESENT  0x00000400
#define RI_ZDE_PRESENT  0x00000800
#define RI_ZCE_PRESENT  0x00001000
#define RI_TRNG_PRESENT 0x00002000
#define RI_ELFC_PRESENT 0x00004000
#define RI_ELFC_SHIFT   14
#define RI_NUM_VQM      0x00078000
#define RI_NVQM_SHIFT   15
#define RI_NVQM(r)      (((r) * RI_NUM_VQM) >> RI_NVQM_SHIFT)
#define RI_LSB_ENTRIES  0x0FF80000
#define RI_NLSB_SHIFT   19
#define RI_NLSB(r)      (((r) * RI_LSB_ENTRIES) >> RI_NLSB_SHIFT)

static ssize_t ccp5_debugfs_info_read(struct file *filp, char __user *ubuf,
                                      size_t count, loff_t *offp)
{
        struct ccp_device *ccp = filp->private_data;
        unsigned int oboff = 0;
        unsigned int regval;
        ssize_t ret;
        char *obuf;

        if (!ccp)
                return 0;

        obuf = kmalloc(OBUFLEN, GFP_KERNEL);
        if (!obuf)
                return -ENOMEM;

        oboff += OSCNPRINTF("Device name: %s\n", ccp->name);
        oboff += OSCNPRINTF("   RNG name: %s\n", ccp->rngname);
        oboff += OSCNPRINTF("   # Queues: %d\n", ccp->cmd_q_count);
        oboff += OSCNPRINTF("     # Cmds: %d\n", ccp->cmd_count);

        regval = ioread32(ccp->io_regs + CMD5_PSP_CCP_VERSION);
        oboff += OSCNPRINTF("    Version: %d\n", regval & RI_VERSION_NUM);
        oboff += OSCNPRINTF("    Engines:");
        if (regval & RI_AES_PRESENT)
                oboff += OSCNPRINTF(" AES");
        if (regval & RI_3DES_PRESENT)
                oboff += OSCNPRINTF(" 3DES");
        if (regval & RI_SHA_PRESENT)
                oboff += OSCNPRINTF(" SHA");
        if (regval & RI_RSA_PRESENT)
                oboff += OSCNPRINTF(" RSA");
        if (regval & RI_ECC_PRESENT)
                oboff += OSCNPRINTF(" ECC");
        if (regval & RI_ZDE_PRESENT)
                oboff += OSCNPRINTF(" ZDE");
        if (regval & RI_ZCE_PRESENT)
                oboff += OSCNPRINTF(" ZCE");
        if (regval & RI_TRNG_PRESENT)
                oboff += OSCNPRINTF(" TRNG");
        oboff += OSCNPRINTF("\n");
        oboff += OSCNPRINTF("     Queues: %d\n",
                   (regval & RI_NUM_VQM) >> RI_NVQM_SHIFT);
        oboff += OSCNPRINTF("LSB Entries: %d\n",
                   (regval & RI_LSB_ENTRIES) >> RI_NLSB_SHIFT);

        ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
        kfree(obuf);

        return ret;
}

/* Return a formatted buffer containing the current
 * statistics across all queues for a CCP.
 */
static ssize_t ccp5_debugfs_stats_read(struct file *filp, char __user *ubuf,
                                       size_t count, loff_t *offp)
{
        struct ccp_device *ccp = filp->private_data;
        unsigned long total_xts_aes_ops = 0;
        unsigned long total_3des_ops = 0;
        unsigned long total_aes_ops = 0;
        unsigned long total_sha_ops = 0;
        unsigned long total_rsa_ops = 0;
        unsigned long total_ecc_ops = 0;
        unsigned long total_pt_ops = 0;
        unsigned long total_ops = 0;
        unsigned int oboff = 0;
        ssize_t ret = 0;
        unsigned int i;
        char *obuf;

        for (i = 0; i < ccp->cmd_q_count; i++) {
                struct ccp_cmd_queue *cmd_q = &ccp->cmd_q[i];

                total_ops += cmd_q->total_ops;
                total_aes_ops += cmd_q->total_aes_ops;
                total_xts_aes_ops += cmd_q->total_xts_aes_ops;
                total_3des_ops += cmd_q->total_3des_ops;
                total_sha_ops += cmd_q->total_sha_ops;
                total_rsa_ops += cmd_q->total_rsa_ops;
                total_pt_ops += cmd_q->total_pt_ops;
                total_ecc_ops += cmd_q->total_ecc_ops;
        }

        obuf = kmalloc(OBUFLEN, GFP_KERNEL);
        if (!obuf)
                return -ENOMEM;

        oboff += OSCNPRINTF("Total Interrupts Handled: %ld\n",
                            ccp->total_interrupts);
        oboff += OSCNPRINTF("        Total Operations: %ld\n",
                            total_ops);
        oboff += OSCNPRINTF("                     AES: %ld\n",
                            total_aes_ops);
        oboff += OSCNPRINTF("                 XTS AES: %ld\n",
                            total_xts_aes_ops);
        oboff += OSCNPRINTF("                     SHA: %ld\n",
                            total_3des_ops);
        oboff += OSCNPRINTF("                     SHA: %ld\n",
                            total_sha_ops);
        oboff += OSCNPRINTF("                     RSA: %ld\n",
                            total_rsa_ops);
        oboff += OSCNPRINTF("               Pass-Thru: %ld\n",
                            total_pt_ops);
        oboff += OSCNPRINTF("                     ECC: %ld\n",
                            total_ecc_ops);

        ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
        kfree(obuf);

        return ret;
}

/* Reset the counters in a queue
 */
static void ccp5_debugfs_reset_queue_stats(struct ccp_cmd_queue *cmd_q)
{
        cmd_q->total_ops = 0L;
        cmd_q->total_aes_ops = 0L;
        cmd_q->total_xts_aes_ops = 0L;
        cmd_q->total_3des_ops = 0L;
        cmd_q->total_sha_ops = 0L;
        cmd_q->total_rsa_ops = 0L;
        cmd_q->total_pt_ops = 0L;
        cmd_q->total_ecc_ops = 0L;
}

/* A value was written to the stats variable, which
 * should be used to reset the queue counters across
 * that device.
 */
static ssize_t ccp5_debugfs_stats_write(struct file *filp,
                                        const char __user *ubuf,
                                        size_t count, loff_t *offp)
{
        struct ccp_device *ccp = filp->private_data;
        int i;

        for (i = 0; i < ccp->cmd_q_count; i++)
                ccp5_debugfs_reset_queue_stats(&ccp->cmd_q[i]);
        ccp->total_interrupts = 0L;

        return count;
}

/* Return a formatted buffer containing the current information
 * for that queue
 */
static ssize_t ccp5_debugfs_queue_read(struct file *filp, char __user *ubuf,
                                       size_t count, loff_t *offp)
{
        struct ccp_cmd_queue *cmd_q = filp->private_data;
        unsigned int oboff = 0;
        unsigned int regval;
        ssize_t ret;
        char *obuf;

        if (!cmd_q)
                return 0;

        obuf = kmalloc(OBUFLEN, GFP_KERNEL);
        if (!obuf)
                return -ENOMEM;

        oboff += OSCNPRINTF("  Total Queue Operations: %ld\n",
                            cmd_q->total_ops);
        oboff += OSCNPRINTF("                     AES: %ld\n",
                            cmd_q->total_aes_ops);
        oboff += OSCNPRINTF("                 XTS AES: %ld\n",
                            cmd_q->total_xts_aes_ops);
        oboff += OSCNPRINTF("                     SHA: %ld\n",
                            cmd_q->total_3des_ops);
        oboff += OSCNPRINTF("                     SHA: %ld\n",
                            cmd_q->total_sha_ops);
        oboff += OSCNPRINTF("                     RSA: %ld\n",
                            cmd_q->total_rsa_ops);
        oboff += OSCNPRINTF("               Pass-Thru: %ld\n",
                            cmd_q->total_pt_ops);
        oboff += OSCNPRINTF("                     ECC: %ld\n",
                            cmd_q->total_ecc_ops);

        regval = ioread32(cmd_q->reg_int_enable);
        oboff += OSCNPRINTF("      Enabled Interrupts:");
        if (regval & INT_EMPTY_QUEUE)
                oboff += OSCNPRINTF(" EMPTY");
        if (regval & INT_QUEUE_STOPPED)
                oboff += OSCNPRINTF(" STOPPED");
        if (regval & INT_ERROR)
                oboff += OSCNPRINTF(" ERROR");
        if (regval & INT_COMPLETION)
                oboff += OSCNPRINTF(" COMPLETION");
        oboff += OSCNPRINTF("\n");

        ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
        kfree(obuf);

        return ret;
}

/* A value was written to the stats variable for a
 * queue. Reset the queue counters to this value.
 */
static ssize_t ccp5_debugfs_queue_write(struct file *filp,
                                        const char __user *ubuf,
                                        size_t count, loff_t *offp)
{
        struct ccp_cmd_queue *cmd_q = filp->private_data;

        ccp5_debugfs_reset_queue_stats(cmd_q);

        return count;
}

static const struct file_operations ccp_debugfs_info_ops = {
        .owner = THIS_MODULE,
        .open = simple_open,
        .read = ccp5_debugfs_info_read,
        .write = NULL,
};

static const struct file_operations ccp_debugfs_queue_ops = {
        .owner = THIS_MODULE,
        .open = simple_open,
        .read = ccp5_debugfs_queue_read,
        .write = ccp5_debugfs_queue_write,
};

static const struct file_operations ccp_debugfs_stats_ops = {
        .owner = THIS_MODULE,
        .open = simple_open,
        .read = ccp5_debugfs_stats_read,
        .write = ccp5_debugfs_stats_write,
};

static struct dentry *ccp_debugfs_dir;
static DEFINE_MUTEX(ccp_debugfs_lock);

#define MAX_NAME_LEN    20

void ccp5_debugfs_setup(struct ccp_device *ccp)
{
        struct ccp_cmd_queue *cmd_q;
        char name[MAX_NAME_LEN + 1];
        struct dentry *debugfs_q_instance;
        int i;

        if (!debugfs_initialized())
                return;

        mutex_lock(&ccp_debugfs_lock);
        if (!ccp_debugfs_dir)
                ccp_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
        mutex_unlock(&ccp_debugfs_lock);

        ccp->debugfs_instance = debugfs_create_dir(ccp->name, ccp_debugfs_dir);

        debugfs_create_file("info", 0400, ccp->debugfs_instance, ccp,
                            &ccp_debugfs_info_ops);

        debugfs_create_file("stats", 0600, ccp->debugfs_instance, ccp,
                            &ccp_debugfs_stats_ops);

        for (i = 0; i < ccp->cmd_q_count; i++) {
                cmd_q = &ccp->cmd_q[i];

                snprintf(name, MAX_NAME_LEN - 1, "q%d", cmd_q->id);

                debugfs_q_instance =
                        debugfs_create_dir(name, ccp->debugfs_instance);

                debugfs_create_file("stats", 0600, debugfs_q_instance, cmd_q,
                                    &ccp_debugfs_queue_ops);
        }

        return;
}

void ccp5_debugfs_destroy(void)
{
        mutex_lock(&ccp_debugfs_lock);
        debugfs_remove_recursive(ccp_debugfs_dir);
        ccp_debugfs_dir = NULL;
        mutex_unlock(&ccp_debugfs_lock);
}