/*
 *  Copyright IBM Corp. 2012
 *  Author(s): Holger Dengler <hd@linux.vnet.ibm.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/atomic.h>
#include <linux/uaccess.h>
#include <linux/mod_devicetable.h>

#include "ap_bus.h"
#include "zcrypt_api.h"
#include "zcrypt_msgtype6.h"
#include "zcrypt_msgtype50.h"
#include "zcrypt_error.h"
#include "zcrypt_cex4.h"

#define CEX4A_MIN_MOD_SIZE	  1	/*    8 bits	*/
#define CEX4A_MAX_MOD_SIZE_2K	256	/* 2048 bits	*/
#define CEX4A_MAX_MOD_SIZE_4K	512	/* 4096 bits	*/

#define CEX4C_MIN_MOD_SIZE	 16	/*  256 bits	*/
#define CEX4C_MAX_MOD_SIZE	512	/* 4096 bits	*/

#define CEX4A_MAX_MESSAGE_SIZE	MSGTYPE50_CRB3_MAX_MSG_SIZE
#define CEX4C_MAX_MESSAGE_SIZE	MSGTYPE06_MAX_MSG_SIZE

/* Waiting time for requests to be processed.
 * Currently there are some types of request which are not deterministic.
 * But the maximum time limit managed by the stomper code is set to 60sec.
 * Hence we have to wait at least that time period.
 */
#define CEX4_CLEANUP_TIME	(900*HZ)

MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("CEX4 Cryptographic Card device driver, " \
		   "Copyright IBM Corp. 2012");
MODULE_LICENSE("GPL");

static struct ap_device_id zcrypt_cex4_card_ids[] = {
	{ .dev_type = AP_DEVICE_TYPE_CEX4,
	  .match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
	{ .dev_type = AP_DEVICE_TYPE_CEX5,
	  .match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
	{ /* end of list */ },
};

MODULE_DEVICE_TABLE(ap, zcrypt_cex4_card_ids);

static struct ap_device_id zcrypt_cex4_queue_ids[] = {
	{ .dev_type = AP_DEVICE_TYPE_CEX4,
	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
	{ .dev_type = AP_DEVICE_TYPE_CEX5,
	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
	{ /* end of list */ },
};

MODULE_DEVICE_TABLE(ap, zcrypt_cex4_queue_ids);

/**
 * Probe function for CEX4 card device. It always accepts the AP device
 * since the bus_match already checked the hardware type.
 * @ap_dev: pointer to the AP device.
 */
static int zcrypt_cex4_card_probe(struct ap_device *ap_dev)
{
	/*
	 * Normalized speed ratings per crypto adapter
	 * MEX_1k, MEX_2k, MEX_4k, CRT_1k, CRT_2k, CRT_4k, RNG, SECKEY
	 */
	static const int CEX4A_SPEED_IDX[] = {
		5,  6,	  59,  20, 115,  581,  0,  0};
	static const int CEX5A_SPEED_IDX[] = {
		3,  3,	   6,	8,  32,  218,  0,  0};
	static const int CEX4C_SPEED_IDX[] = {
		24,  25,   82,	41, 138, 1111, 79,  8};
	static const int CEX5C_SPEED_IDX[] = {
		10,  14,   23,	17,  45,  242, 63,  4};
	static const int CEX4P_SPEED_IDX[] = {
		142, 198, 1852, 203, 331, 1563,  0,  8};
	static const int CEX5P_SPEED_IDX[] = {
		49,  67,  131,	52,  85,  287,	0,  4};

	struct ap_card *ac = to_ap_card(&ap_dev->device);
	struct zcrypt_card *zc;
	int rc = 0;

	zc = zcrypt_card_alloc();
	if (!zc)
		return -ENOMEM;
	zc->card = ac;
	ac->private = zc;
	if (ap_test_bit(&ac->functions, AP_FUNC_ACCEL)) {
		if (ac->ap_dev.device_type == AP_DEVICE_TYPE_CEX4) {
			zc->type_string = "CEX4A";
			zc->user_space_type = ZCRYPT_CEX4;
			memcpy(zc->speed_rating, CEX4A_SPEED_IDX,
			       sizeof(CEX4A_SPEED_IDX));
		} else {
			zc->type_string = "CEX5A";
			zc->user_space_type = ZCRYPT_CEX5;
			memcpy(zc->speed_rating, CEX5A_SPEED_IDX,
			       sizeof(CEX5A_SPEED_IDX));
		}
		zc->min_mod_size = CEX4A_MIN_MOD_SIZE;
		if (ap_test_bit(&ac->functions, AP_FUNC_MEX4K) &&
		    ap_test_bit(&ac->functions, AP_FUNC_CRT4K)) {
			zc->max_mod_size = CEX4A_MAX_MOD_SIZE_4K;
			zc->max_exp_bit_length =
				CEX4A_MAX_MOD_SIZE_4K;
		} else {
			zc->max_mod_size = CEX4A_MAX_MOD_SIZE_2K;
			zc->max_exp_bit_length =
				CEX4A_MAX_MOD_SIZE_2K;
		}
	} else if (ap_test_bit(&ac->functions, AP_FUNC_COPRO)) {
		if (ac->ap_dev.device_type == AP_DEVICE_TYPE_CEX4) {
			zc->type_string = "CEX4C";
			/* wrong user space type, must be CEX4
			 * just keep it for cca compatibility
			 */
			zc->user_space_type = ZCRYPT_CEX3C;
			memcpy(zc->speed_rating, CEX4C_SPEED_IDX,
			       sizeof(CEX4C_SPEED_IDX));
		} else {
			zc->type_string = "CEX5C";
			/* wrong user space type, must be CEX5
			 * just keep it for cca compatibility
			 */
			zc->user_space_type = ZCRYPT_CEX3C;
			memcpy(zc->speed_rating, CEX5C_SPEED_IDX,
			       sizeof(CEX5C_SPEED_IDX));
		}
		zc->min_mod_size = CEX4C_MIN_MOD_SIZE;
		zc->max_mod_size = CEX4C_MAX_MOD_SIZE;
		zc->max_exp_bit_length = CEX4C_MAX_MOD_SIZE;
	} else if (ap_test_bit(&ac->functions, AP_FUNC_EP11)) {
		if (ac->ap_dev.device_type == AP_DEVICE_TYPE_CEX4) {
			zc->type_string = "CEX4P";
			zc->user_space_type = ZCRYPT_CEX4;
			memcpy(zc->speed_rating, CEX4P_SPEED_IDX,
			       sizeof(CEX4P_SPEED_IDX));
		} else {
			zc->type_string = "CEX5P";
			zc->user_space_type = ZCRYPT_CEX5;
			memcpy(zc->speed_rating, CEX5P_SPEED_IDX,
			       sizeof(CEX5P_SPEED_IDX));
		}
		zc->min_mod_size = CEX4C_MIN_MOD_SIZE;
		zc->max_mod_size = CEX4C_MAX_MOD_SIZE;
		zc->max_exp_bit_length = CEX4C_MAX_MOD_SIZE;
	} else {
		zcrypt_card_free(zc);
		return -ENODEV;
	}
	zc->online = 1;

	rc = zcrypt_card_register(zc);
	if (rc) {
		ac->private = NULL;
		zcrypt_card_free(zc);
	}

	return rc;
}

/**
 * This is called to remove the CEX4 card driver information
 * if an AP card device is removed.
 */
static void zcrypt_cex4_card_remove(struct ap_device *ap_dev)
{
	struct zcrypt_card *zc = to_ap_card(&ap_dev->device)->private;

	if (zc)
		zcrypt_card_unregister(zc);
}

static struct ap_driver zcrypt_cex4_card_driver = {
	.probe = zcrypt_cex4_card_probe,
	.remove = zcrypt_cex4_card_remove,
	.ids = zcrypt_cex4_card_ids,
};

/**
 * Probe function for CEX4 queue device. It always accepts the AP device
 * since the bus_match already checked the hardware type.
 * @ap_dev: pointer to the AP device.
 */
static int zcrypt_cex4_queue_probe(struct ap_device *ap_dev)
{
	struct ap_queue *aq = to_ap_queue(&ap_dev->device);
	struct zcrypt_queue *zq;
	int rc;

	if (ap_test_bit(&aq->card->functions, AP_FUNC_ACCEL)) {
		zq = zcrypt_queue_alloc(CEX4A_MAX_MESSAGE_SIZE);
		if (!zq)
			return -ENOMEM;
		zq->ops = zcrypt_msgtype(MSGTYPE50_NAME,
					 MSGTYPE50_VARIANT_DEFAULT);
	} else if (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO)) {
		zq = zcrypt_queue_alloc(CEX4C_MAX_MESSAGE_SIZE);
		if (!zq)
			return -ENOMEM;
		zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
					 MSGTYPE06_VARIANT_DEFAULT);
	} else if (ap_test_bit(&aq->card->functions, AP_FUNC_EP11)) {
		zq = zcrypt_queue_alloc(CEX4C_MAX_MESSAGE_SIZE);
		if (!zq)
			return -ENOMEM;
		zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
					 MSGTYPE06_VARIANT_EP11);
	} else {
		return -ENODEV;
	}
	zq->queue = aq;
	zq->online = 1;
	atomic_set(&zq->load, 0);
	ap_queue_init_reply(aq, &zq->reply);
	aq->request_timeout = CEX4_CLEANUP_TIME,
	aq->private = zq;
	rc = zcrypt_queue_register(zq);
	if (rc) {
		aq->private = NULL;
		zcrypt_queue_free(zq);
	}

	return rc;
}

/**
 * This is called to remove the CEX4 queue driver information
 * if an AP queue device is removed.
 */
static void zcrypt_cex4_queue_remove(struct ap_device *ap_dev)
{
	struct ap_queue *aq = to_ap_queue(&ap_dev->device);
	struct zcrypt_queue *zq = aq->private;

	ap_queue_remove(aq);
	if (zq)
		zcrypt_queue_unregister(zq);
}

static struct ap_driver zcrypt_cex4_queue_driver = {
	.probe = zcrypt_cex4_queue_probe,
	.remove = zcrypt_cex4_queue_remove,
	.suspend = ap_queue_suspend,
	.resume = ap_queue_resume,
	.ids = zcrypt_cex4_queue_ids,
};

int __init zcrypt_cex4_init(void)
{
	int rc;

	rc = ap_driver_register(&zcrypt_cex4_card_driver,
				THIS_MODULE, "cex4card");
	if (rc)
		return rc;

	rc = ap_driver_register(&zcrypt_cex4_queue_driver,
				THIS_MODULE, "cex4queue");
	if (rc)
		ap_driver_unregister(&zcrypt_cex4_card_driver);

	return rc;
}

void __exit zcrypt_cex4_exit(void)
{
	ap_driver_unregister(&zcrypt_cex4_queue_driver);
	ap_driver_unregister(&zcrypt_cex4_card_driver);
}

module_init(zcrypt_cex4_init);
module_exit(zcrypt_cex4_exit);