/*
 * Marvell NFC driver: Firmware downloader
 *
 * Copyright (C) 2015, Marvell International Ltd.
 *
 * This software file (the "File") is distributed by Marvell International
 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
 * (the "License").  You may use, redistribute and/or modify this File in
 * accordance with the terms and conditions of the License, a copy of which
 * is available on the worldwide web at
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
 *
 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
 * this warranty disclaimer.
 */

#include <linux/module.h>
#include <linux/unaligned/access_ok.h>
#include <linux/firmware.h>
#include <linux/nfc.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include "nfcmrvl.h"

#define FW_DNLD_TIMEOUT			15000

#define NCI_OP_PROPRIETARY_BOOT_CMD	nci_opcode_pack(NCI_GID_PROPRIETARY, \
							NCI_OP_PROP_BOOT_CMD)

/* FW download states */

enum {
	STATE_RESET = 0,
	STATE_INIT,
	STATE_SET_REF_CLOCK,
	STATE_SET_HI_CONFIG,
	STATE_OPEN_LC,
	STATE_FW_DNLD,
	STATE_CLOSE_LC,
	STATE_BOOT
};

enum {
	SUBSTATE_WAIT_COMMAND = 0,
	SUBSTATE_WAIT_ACK_CREDIT,
	SUBSTATE_WAIT_NACK_CREDIT,
	SUBSTATE_WAIT_DATA_CREDIT,
};

/*
** Patterns for responses
*/

static const uint8_t nci_pattern_core_reset_ntf[] = {
	0x60, 0x00, 0x02, 0xA0, 0x01
};

static const uint8_t nci_pattern_core_init_rsp[] = {
	0x40, 0x01, 0x11
};

static const uint8_t nci_pattern_core_set_config_rsp[] = {
	0x40, 0x02, 0x02, 0x00, 0x00
};

static const uint8_t nci_pattern_core_conn_create_rsp[] = {
	0x40, 0x04, 0x04, 0x00
};

static const uint8_t nci_pattern_core_conn_close_rsp[] = {
	0x40, 0x05, 0x01, 0x00
};

static const uint8_t nci_pattern_core_conn_credits_ntf[] = {
	0x60, 0x06, 0x03, 0x01, NCI_CORE_LC_CONNID_PROP_FW_DL, 0x01
};

static const uint8_t nci_pattern_proprietary_boot_rsp[] = {
	0x4F, 0x3A, 0x01, 0x00
};

static struct sk_buff *alloc_lc_skb(struct nfcmrvl_private *priv, uint8_t plen)
{
	struct sk_buff *skb;
	struct nci_data_hdr *hdr;

	skb = nci_skb_alloc(priv->ndev, (NCI_DATA_HDR_SIZE + plen), GFP_KERNEL);
	if (!skb) {
		pr_err("no memory for data\n");
		return NULL;
	}

	hdr = (struct nci_data_hdr *) skb_put(skb, NCI_DATA_HDR_SIZE);
	hdr->conn_id = NCI_CORE_LC_CONNID_PROP_FW_DL;
	hdr->rfu = 0;
	hdr->plen = plen;

	nci_mt_set((__u8 *)hdr, NCI_MT_DATA_PKT);
	nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);

	return skb;
}

static void fw_dnld_over(struct nfcmrvl_private *priv, u32 error)
{
	if (priv->fw_dnld.fw) {
		release_firmware(priv->fw_dnld.fw);
		priv->fw_dnld.fw = NULL;
		priv->fw_dnld.header = NULL;
		priv->fw_dnld.binary_config = NULL;
	}

	atomic_set(&priv->ndev->cmd_cnt, 0);

	if (timer_pending(&priv->ndev->cmd_timer))
		del_timer_sync(&priv->ndev->cmd_timer);

	if (timer_pending(&priv->fw_dnld.timer))
		del_timer_sync(&priv->fw_dnld.timer);

	nfc_info(priv->dev, "FW loading over (%d)]\n", error);

	if (error != 0) {
		/* failed, halt the chip to avoid power consumption */
		nfcmrvl_chip_halt(priv);
	}

	nfc_fw_download_done(priv->ndev->nfc_dev, priv->fw_dnld.name, error);
}

static void fw_dnld_timeout(unsigned long arg)
{
	struct nfcmrvl_private *priv = (struct nfcmrvl_private *) arg;

	nfc_err(priv->dev, "FW loading timeout");
	priv->fw_dnld.state = STATE_RESET;
	fw_dnld_over(priv, -ETIMEDOUT);
}

static int process_state_reset(struct nfcmrvl_private *priv,
			       struct sk_buff *skb)
{
	if (sizeof(nci_pattern_core_reset_ntf) != skb->len ||
	    memcmp(skb->data, nci_pattern_core_reset_ntf,
		   sizeof(nci_pattern_core_reset_ntf)))
		return -EINVAL;

	nfc_info(priv->dev, "BootROM reset, start fw download\n");

	/* Start FW download state machine */
	priv->fw_dnld.state = STATE_INIT;
	nci_send_cmd(priv->ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);

	return 0;
}

static int process_state_init(struct nfcmrvl_private *priv, struct sk_buff *skb)
{
	struct nci_core_set_config_cmd cmd;

	if (sizeof(nci_pattern_core_init_rsp) >= skb->len ||
	    memcmp(skb->data, nci_pattern_core_init_rsp,
		   sizeof(nci_pattern_core_init_rsp)))
		return -EINVAL;

	cmd.num_params = 1;
	cmd.param.id = NFCMRVL_PROP_REF_CLOCK;
	cmd.param.len = 4;
	memcpy(cmd.param.val, &priv->fw_dnld.header->ref_clock, 4);

	nci_send_cmd(priv->ndev, NCI_OP_CORE_SET_CONFIG_CMD, 3 + cmd.param.len,
		     &cmd);

	priv->fw_dnld.state = STATE_SET_REF_CLOCK;
	return 0;
}

static void create_lc(struct nfcmrvl_private *priv)
{
	uint8_t param[2] = { NCI_CORE_LC_PROP_FW_DL, 0x0 };

	priv->fw_dnld.state = STATE_OPEN_LC;
	nci_send_cmd(priv->ndev, NCI_OP_CORE_CONN_CREATE_CMD, 2, param);
}

static int process_state_set_ref_clock(struct nfcmrvl_private *priv,
				       struct sk_buff *skb)
{
	struct nci_core_set_config_cmd cmd;

	if (sizeof(nci_pattern_core_set_config_rsp) != skb->len ||
	    memcmp(skb->data, nci_pattern_core_set_config_rsp, skb->len))
		return -EINVAL;

	cmd.num_params = 1;
	cmd.param.id = NFCMRVL_PROP_SET_HI_CONFIG;

	switch (priv->phy) {
	case NFCMRVL_PHY_UART:
		cmd.param.len = 5;
		memcpy(cmd.param.val,
		       &priv->fw_dnld.binary_config->uart.baudrate,
		       4);
		cmd.param.val[4] =
			priv->fw_dnld.binary_config->uart.flow_control;
		break;
	case NFCMRVL_PHY_I2C:
		cmd.param.len = 5;
		memcpy(cmd.param.val,
		       &priv->fw_dnld.binary_config->i2c.clk,
		       4);
		cmd.param.val[4] = 0;
		break;
	case NFCMRVL_PHY_SPI:
		cmd.param.len = 5;
		memcpy(cmd.param.val,
		       &priv->fw_dnld.binary_config->spi.clk,
		       4);
		cmd.param.val[4] = 0;
		break;
	default:
		create_lc(priv);
		return 0;
	}

	priv->fw_dnld.state = STATE_SET_HI_CONFIG;
	nci_send_cmd(priv->ndev, NCI_OP_CORE_SET_CONFIG_CMD, 3 + cmd.param.len,
		     &cmd);
	return 0;
}

static int process_state_set_hi_config(struct nfcmrvl_private *priv,
				       struct sk_buff *skb)
{
	if (sizeof(nci_pattern_core_set_config_rsp) != skb->len ||
	    memcmp(skb->data, nci_pattern_core_set_config_rsp, skb->len))
		return -EINVAL;

	create_lc(priv);
	return 0;
}

static int process_state_open_lc(struct nfcmrvl_private *priv,
				 struct sk_buff *skb)
{
	if (sizeof(nci_pattern_core_conn_create_rsp) >= skb->len ||
	    memcmp(skb->data, nci_pattern_core_conn_create_rsp,
		   sizeof(nci_pattern_core_conn_create_rsp)))
		return -EINVAL;

	priv->fw_dnld.state = STATE_FW_DNLD;
	priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
	priv->fw_dnld.offset = priv->fw_dnld.binary_config->offset;
	return 0;
}

static int process_state_fw_dnld(struct nfcmrvl_private *priv,
				 struct sk_buff *skb)
{
	uint16_t len;
	uint16_t comp_len;
	struct sk_buff *out_skb;

	switch (priv->fw_dnld.substate) {
	case SUBSTATE_WAIT_COMMAND:
		/*
		 * Command format:
		 * B0..2: NCI header
		 * B3   : Helper command (0xA5)
		 * B4..5: le16 data size
		 * B6..7: le16 data size complement (~)
		 * B8..N: payload
		 */

		/* Remove NCI HDR */
		skb_pull(skb, 3);
		if (skb->data[0] != HELPER_CMD_PACKET_FORMAT || skb->len != 5) {
			nfc_err(priv->dev, "bad command");
			return -EINVAL;
		}
		skb_pull(skb, 1);
		memcpy(&len, skb->data, 2);
		skb_pull(skb, 2);
		memcpy(&comp_len, skb->data, 2);
		skb_pull(skb, 2);
		len = get_unaligned_le16(&len);
		comp_len = get_unaligned_le16(&comp_len);
		if (((~len) & 0xFFFF) != comp_len) {
			nfc_err(priv->dev, "bad len complement: %x %x %x",
				len, comp_len, (~len & 0xFFFF));
			out_skb = alloc_lc_skb(priv, 1);
			if (!out_skb)
				return -ENOMEM;
			*skb_put(out_skb, 1) = 0xBF;
			nci_send_frame(priv->ndev, out_skb);
			priv->fw_dnld.substate = SUBSTATE_WAIT_NACK_CREDIT;
			return 0;
		}
		priv->fw_dnld.chunk_len = len;
		out_skb = alloc_lc_skb(priv, 1);
		if (!out_skb)
			return -ENOMEM;
		*skb_put(out_skb, 1) = HELPER_ACK_PACKET_FORMAT;
		nci_send_frame(priv->ndev, out_skb);
		priv->fw_dnld.substate = SUBSTATE_WAIT_ACK_CREDIT;
		break;

	case SUBSTATE_WAIT_ACK_CREDIT:
		if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
		    memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
			   skb->len)) {
			nfc_err(priv->dev, "bad packet: waiting for credit");
			return -EINVAL;
		}
		if (priv->fw_dnld.chunk_len == 0) {
			/* FW Loading is done */
			uint8_t conn_id = NCI_CORE_LC_CONNID_PROP_FW_DL;

			priv->fw_dnld.state = STATE_CLOSE_LC;
			nci_send_cmd(priv->ndev, NCI_OP_CORE_CONN_CLOSE_CMD,
				     1, &conn_id);
		} else {
			out_skb = alloc_lc_skb(priv, priv->fw_dnld.chunk_len);
			if (!out_skb)
				return -ENOMEM;
			memcpy(skb_put(out_skb, priv->fw_dnld.chunk_len),
			       ((uint8_t *)priv->fw_dnld.fw->data) +
			       priv->fw_dnld.offset,
			       priv->fw_dnld.chunk_len);
			nci_send_frame(priv->ndev, out_skb);
			priv->fw_dnld.substate = SUBSTATE_WAIT_DATA_CREDIT;
		}
		break;

	case SUBSTATE_WAIT_DATA_CREDIT:
		if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
		    memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
			    skb->len)) {
			nfc_err(priv->dev, "bad packet: waiting for credit");
			return -EINVAL;
		}
		priv->fw_dnld.offset += priv->fw_dnld.chunk_len;
		priv->fw_dnld.chunk_len = 0;
		priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
		break;

	case SUBSTATE_WAIT_NACK_CREDIT:
		if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
		    memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
			    skb->len)) {
			nfc_err(priv->dev, "bad packet: waiting for credit");
			return -EINVAL;
		}
		priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
		break;
	}
	return 0;
}

static int process_state_close_lc(struct nfcmrvl_private *priv,
				  struct sk_buff *skb)
{
	if (sizeof(nci_pattern_core_conn_close_rsp) != skb->len ||
	    memcmp(skb->data, nci_pattern_core_conn_close_rsp, skb->len))
		return -EINVAL;

	priv->fw_dnld.state = STATE_BOOT;
	nci_send_cmd(priv->ndev, NCI_OP_PROPRIETARY_BOOT_CMD, 0, NULL);
	return 0;
}

static int process_state_boot(struct nfcmrvl_private *priv, struct sk_buff *skb)
{
	if (sizeof(nci_pattern_proprietary_boot_rsp) != skb->len ||
	    memcmp(skb->data, nci_pattern_proprietary_boot_rsp, skb->len))
		return -EINVAL;

	/*
	 * Update HI config to use the right configuration for the next
	 * data exchanges.
	 */
	priv->if_ops->nci_update_config(priv,
					&priv->fw_dnld.binary_config->config);

	if (priv->fw_dnld.binary_config == &priv->fw_dnld.header->helper) {
		/*
		 * This is the case where an helper was needed and we have
		 * uploaded it. Now we have to wait the next RESET NTF to start
		 * FW download.
		 */
		priv->fw_dnld.state = STATE_RESET;
		priv->fw_dnld.binary_config = &priv->fw_dnld.header->firmware;
		nfc_info(priv->dev, "FW loading: helper loaded");
	} else {
		nfc_info(priv->dev, "FW loading: firmware loaded");
		fw_dnld_over(priv, 0);
	}
	return 0;
}

static void fw_dnld_rx_work(struct work_struct *work)
{
	int ret;
	struct sk_buff *skb;
	struct nfcmrvl_fw_dnld *fw_dnld = container_of(work,
						       struct nfcmrvl_fw_dnld,
						       rx_work);
	struct nfcmrvl_private *priv = container_of(fw_dnld,
						    struct nfcmrvl_private,
						    fw_dnld);

	while ((skb = skb_dequeue(&fw_dnld->rx_q))) {
		nfc_send_to_raw_sock(priv->ndev->nfc_dev, skb,
				     RAW_PAYLOAD_NCI, NFC_DIRECTION_RX);
		switch (fw_dnld->state) {
		case STATE_RESET:
			ret = process_state_reset(priv, skb);
			break;
		case STATE_INIT:
			ret = process_state_init(priv, skb);
			break;
		case STATE_SET_REF_CLOCK:
			ret = process_state_set_ref_clock(priv, skb);
			break;
		case STATE_SET_HI_CONFIG:
			ret = process_state_set_hi_config(priv, skb);
			break;
		case STATE_OPEN_LC:
			ret = process_state_open_lc(priv, skb);
			break;
		case STATE_FW_DNLD:
			ret = process_state_fw_dnld(priv, skb);
			break;
		case STATE_CLOSE_LC:
			ret = process_state_close_lc(priv, skb);
			break;
		case STATE_BOOT:
			ret = process_state_boot(priv, skb);
			break;
		default:
			ret = -EFAULT;
		}

		kfree_skb(skb);

		if (ret != 0) {
			nfc_err(priv->dev, "FW loading error");
			fw_dnld_over(priv, ret);
			break;
		}
	}
}

int	nfcmrvl_fw_dnld_init(struct nfcmrvl_private *priv)
{
	char name[32];

	INIT_WORK(&priv->fw_dnld.rx_work, fw_dnld_rx_work);
	snprintf(name, sizeof(name), "%s_nfcmrvl_fw_dnld_rx_wq",
		 dev_name(priv->dev));
	priv->fw_dnld.rx_wq = create_singlethread_workqueue(name);
	if (!priv->fw_dnld.rx_wq)
		return -ENOMEM;
	skb_queue_head_init(&priv->fw_dnld.rx_q);
	return 0;
}

void	nfcmrvl_fw_dnld_deinit(struct nfcmrvl_private *priv)
{
	destroy_workqueue(priv->fw_dnld.rx_wq);
}

void	nfcmrvl_fw_dnld_recv_frame(struct nfcmrvl_private *priv,
				   struct sk_buff *skb)
{
	/* Discard command timer */
	if (timer_pending(&priv->ndev->cmd_timer))
		del_timer_sync(&priv->ndev->cmd_timer);

	/* Allow next command */
	atomic_set(&priv->ndev->cmd_cnt, 1);

	/* Queue and trigger rx work */
	skb_queue_tail(&priv->fw_dnld.rx_q, skb);
	queue_work(priv->fw_dnld.rx_wq, &priv->fw_dnld.rx_work);
}

void nfcmrvl_fw_dnld_abort(struct nfcmrvl_private *priv)
{
	fw_dnld_over(priv, -EHOSTDOWN);
}

int nfcmrvl_fw_dnld_start(struct nci_dev *ndev, const char *firmware_name)
{
	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
	struct nfcmrvl_fw_dnld *fw_dnld = &priv->fw_dnld;

	if (!priv->support_fw_dnld)
		return -ENOTSUPP;

	if (!firmware_name || !firmware_name[0])
		return -EINVAL;

	strcpy(fw_dnld->name, firmware_name);

	/*
	 * Retrieve FW binary file and parse it to initialize FW download
	 * state machine.
	 */

	/* Retrieve FW binary */
	if (request_firmware(&fw_dnld->fw, firmware_name, priv->dev) < 0) {
		nfc_err(priv->dev, "failed to retrieve FW %s", firmware_name);
		return -ENOENT;
	}

	fw_dnld->header = (const struct nfcmrvl_fw *) priv->fw_dnld.fw->data;

	if (fw_dnld->header->magic != NFCMRVL_FW_MAGIC ||
	    fw_dnld->header->phy != priv->phy) {
		nfc_err(priv->dev, "bad firmware binary %s magic=0x%x phy=%d",
			firmware_name, fw_dnld->header->magic,
			fw_dnld->header->phy);
		release_firmware(fw_dnld->fw);
		fw_dnld->header = NULL;
		return -EINVAL;
	}

	if (fw_dnld->header->helper.offset != 0) {
		nfc_info(priv->dev, "loading helper");
		fw_dnld->binary_config = &fw_dnld->header->helper;
	} else {
		nfc_info(priv->dev, "loading firmware");
		fw_dnld->binary_config = &fw_dnld->header->firmware;
	}

	/* Configure a timer for timeout */
	setup_timer(&priv->fw_dnld.timer, fw_dnld_timeout,
		    (unsigned long) priv);
	mod_timer(&priv->fw_dnld.timer,
		  jiffies + msecs_to_jiffies(FW_DNLD_TIMEOUT));

	/* Ronfigure HI to be sure that it is the bootrom values */
	priv->if_ops->nci_update_config(priv,
					&fw_dnld->header->bootrom.config);

	/* Allow first command */
	atomic_set(&priv->ndev->cmd_cnt, 1);

	/* First, reset the chip */
	priv->fw_dnld.state = STATE_RESET;
	nfcmrvl_chip_reset(priv);

	/* Now wait for CORE_RESET_NTF or timeout */

	return 0;
}