/*
 * Copyright 2014 Vitalii Demianets
 * Copyright 2014 KnCMiner
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 3 of the License, or (at your option)
 * any later version.  See COPYING for more details.
 */

#include <zlib.h>

#include "miner.h"
#include "logging.h"
#include "lowl-spi.h"

#include "titan-asic.h"

/* ASIC Command codes */
#define	KNC_ASIC_CMD_GETINFO		0x80
#define	KNC_ASIC_CMD_REPORT		0x82
#define	KNC_ASIC_CMD_SETWORK		0x81
#define	KNC_ASIC_CMD_SETWORK_URGENT	0x83
#define	KNC_ASIC_CMD_SETUP_CORE		0x87

/* Error bits */
#define	ERR_SEND_CRC_FAIL	(1 << 0)
#define	ERR_RCV_CRC_FAIL	(1 << 1)
#define	ERR_BAD_RESPONSE	(1 << 2)
#define	ERR_OTHER_ERR		(1 << 31)

#define	CRC32_SIZE			4
/* In SPI responses after crc goes trailer: status(1 byte) + address(3 bytes) */
#define	SPI_RESPONSE_TRAILER_SIZE	4

#define	RCV_STATUS_NOFLAGS	0x81
#define	RCV_STATUS_ACCEPTED_WORK (1 << 2)
#define	RCV_STATUS_SEND_CRC_BAD	(1 << 5)

/* send_size - size of send_buf, without crc
 * transfer_size - total size of transfer
 */
static uint8_t * spi_transfer(struct spi_port * const spi, uint8_t *send_buf, int send_size, int transfer_size, int rcv_crc_data_len, uint32_t *errors, bool *work_accepted)
{
	uint8_t *rxbuf, crcbuf[CRC32_SIZE];
	uint32_t crc;
	uint8_t rcv_status;
	int min_transfer_size = send_size + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE;
	if (0 < rcv_crc_data_len) {
		if (min_transfer_size < (4 + rcv_crc_data_len + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE))
			min_transfer_size = 4 + rcv_crc_data_len + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE;
	}

	*errors = 0;
	*work_accepted = false;
	if (transfer_size < min_transfer_size) {
exit_other_error:
		*errors |= ERR_OTHER_ERR;
		return NULL;
	}
	spi_clear_buf(spi);
	spi_emit_buf(spi, send_buf, send_size);
	crc = crc32(0, Z_NULL, 0);
	crc = crc32(crc, send_buf, send_size);
	*((uint32_t *)crcbuf) = htobe32(crc);
	spi_emit_buf(spi, crcbuf, CRC32_SIZE);
	spi_emit_nop(spi, transfer_size - spi_getbufsz(spi));
	if (!spi_txrx(spi))
		goto exit_other_error;
	rxbuf = spi_getrxbuf(spi);

	rcv_status = rxbuf[transfer_size - SPI_RESPONSE_TRAILER_SIZE];
	if (RCV_STATUS_NOFLAGS != (rcv_status & (~(RCV_STATUS_SEND_CRC_BAD | RCV_STATUS_ACCEPTED_WORK))))
		*errors |= ERR_BAD_RESPONSE;
	if (rcv_status & RCV_STATUS_SEND_CRC_BAD)
		*errors |= ERR_SEND_CRC_FAIL;
	if (0 < rcv_crc_data_len) {
		crc = crc32(0, Z_NULL, 0);
		crc = crc32(crc, rxbuf + 4, rcv_crc_data_len);
		memcpy(crcbuf, &rxbuf[4 + rcv_crc_data_len], CRC32_SIZE);
		if (crc != be32toh(*((uint32_t *)crcbuf)))
			*errors |= ERR_RCV_CRC_FAIL;
	}
	*work_accepted = ((0 == *errors) && (rcv_status & RCV_STATUS_ACCEPTED_WORK));
#if 0
	{
		uint8_t *txbuf = spi_gettxbuf(spi);
		char str[8192];
		int i, n;
		n = 0;
		for (i = 0; i < transfer_size; ++i)
			n += sprintf(&str[n], i ? ",0x%02hhX" : "0x%02hhX", txbuf[i]);
		applog(LOG_NOTICE, "TX: %s", str);
		n = 0;
		for (i = 0; i < transfer_size; ++i)
			n += sprintf(&str[n], i ? ",0x%02hhX" : "0x%02hhX", rxbuf[i]);
		applog(LOG_NOTICE, "RX: %s", str);
		if (0 < rcv_crc_data_len)
			applog(LOG_NOTICE, "RX-CRC: 0x%08X", crc);
	}
#endif
	return rxbuf;
}

/*
 * core_hint - which number of cores is expected. The function needs to know it to
 *   calculate the SPI transfer size. It uses this hint for the first transfer.
 *   If the first transfer fails, it assumes that it is because of wrong hint and
 *   then tries to detect right number of cores from the first response.
 */
bool knc_titan_spi_get_info(const char *repr, struct spi_port * const spi, struct titan_info_response *resp, int die, int core_hint)
{
	uint8_t get_info_cmd[] = {KNC_ASIC_CMD_GETINFO, die, 0x00, 0x00};
	uint8_t *rxbuf;
	uint32_t errors;
	uint16_t revision;
	int transfer_size = 24 + ((core_hint + 3) / 4);
	int i, core;
	bool unused;

	for (i = 0; i < 3; ++i) {
		rxbuf = spi_transfer(spi, get_info_cmd, sizeof(get_info_cmd), transfer_size, transfer_size - 4 - CRC32_SIZE - SPI_RESPONSE_TRAILER_SIZE, &errors, &unused);
		if (NULL == rxbuf) {
exit_unrec_error:	applog(LOG_ERR, "%s[%d] knc_titan_spi_get_info: Unrecognized error", repr, die);
			return false;
		}
		if (errors != ERR_SEND_CRC_FAIL)
			break;
		/* If the only error is SEND_CRC, assume there was a communication error
		 * and retry three times
		 */
	}
	if (ERR_SEND_CRC_FAIL == errors) {
		applog(LOG_ERR, "%s[%d] knc_titan_spi_get_info: CRC error in Tx", repr, die);
		return false;
	}

	if (0 != errors) {
		/* It might be that we have different number of cores. Try to guess it
		 * from partial response.
		 */
		revision = (rxbuf[6] << 8) | rxbuf[7];
		if (KNC_TITAN_ASIC_REVISION != revision) {
exit_bad_revision:	applog(LOG_ERR, "%s[%d] knc_titan_spi_get_info: Bad revision 0x%04hX", repr, die, revision);
			return false;
		}
		resp->cores = (rxbuf[4] << 8) | rxbuf[5];
		if (resp->cores != core_hint) {
			applog(LOG_NOTICE, "%s[%d] core hint %d might be wrong, new guess is %d", repr, die, core_hint, resp->cores);
			transfer_size = 24 + ((resp->cores + 3) / 4);
			for (i = 0; i < 3; ++i) {
				rxbuf = spi_transfer(spi, get_info_cmd, sizeof(get_info_cmd), transfer_size, transfer_size - 4 - CRC32_SIZE - SPI_RESPONSE_TRAILER_SIZE, &errors, &unused);
				if (NULL == rxbuf)
					goto exit_unrec_error;
				if (errors != ERR_SEND_CRC_FAIL)
					break;
				/* If the only error is SEND_CRC, assume there was a communication error
				 * and retry three times
				 */
			}
		}
	}

	if (0 != errors) {
		applog(LOG_ERR, "%s[%d] knc_titan_spi_get_info: Communication failed, errors = 0x%X", repr, die, errors);
		return false;
	}

	revision = (rxbuf[6] << 8) | rxbuf[7];
	if (KNC_TITAN_ASIC_REVISION != revision)
		goto exit_bad_revision;
	resp->cores = (rxbuf[4] << 8) | rxbuf[5];
	resp->pll_state = *((uint64_t *)(&rxbuf[8]));
	for (core = 0; core < resp->cores; ) {
		uint8_t data = rxbuf[16 + (core / 4)];
		resp->want_work[core] = !!(data & (1 << 7));
		resp->have_report[core] = !!(data & (1 << 6));
		if (++core >= resp->cores)
			break;
		resp->want_work[core] = !!(data & (1 << 5));
		resp->have_report[core] = !!(data & (1 << 4));
		if (++core >= resp->cores)
			break;
		resp->want_work[core] = !!(data & (1 << 3));
		resp->have_report[core] = !!(data & (1 << 2));
		if (++core >= resp->cores)
			break;
		resp->want_work[core] = !!(data & (1 << 1));
		resp->have_report[core] = !!(data & (1 << 0));
		if (++core >= resp->cores)
			break;
	}

	return true;
}

static void knc_titan_parse_get_report(uint8_t *data, struct titan_report *report)
{
	int i;

	report->flags = data[0];
	report->core_counter = data[1];
	report->slot_core = (data[2] >> 4) & 0x0F;
	for (i = 0; i < KNC_TITAN_NONCES_PER_REPORT; ++i) {
		report->nonces[i].slot = data[2 + i * 5] & 0x0F;
		report->nonces[i].nonce = ((uint32_t)data[2 + i * 5 + 1] << 24) |
					  ((uint32_t)data[2 + i * 5 + 2] << 16) |
					  ((uint32_t)data[2 + i * 5 + 3] << 8) |
					  ((uint32_t)data[2 + i * 5 + 4]);
	}
}

bool knc_titan_set_work(const char *repr, struct spi_port * const spi, struct titan_report *report, int die, int core, int slot, struct work *work, bool urgent, bool *work_accepted)
{
#define	SETWORK_CMD_SIZE	(5 + BLOCK_HEADER_BYTES_WITHOUT_NONCE)
	uint8_t set_work_cmd_aligned[3 + SETWORK_CMD_SIZE] = {
		0, 0, 0, /* three extra bytes for alignment */
		urgent ? KNC_ASIC_CMD_SETWORK_URGENT : KNC_ASIC_CMD_SETWORK,
		die,
		(core >> 8) & 0xFF,
		core & 0xFF,
		0xF0 | (slot & 0x0F),
		/* next follows data. Thanks to the first three extra bytes it is 64bit-aligned */
	};
	const int send_size = sizeof(set_work_cmd_aligned) - 3;
	const int transfer_size = send_size + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE;
	uint8_t *rxbuf;
	int i;
	uint32_t *src, *dst;
	uint32_t errors;

	if (NULL != work) {
		src = (uint32_t *)work->data;
		dst = (uint32_t *)(&set_work_cmd_aligned[3 + 5]);
		for (i = 0; i < (BLOCK_HEADER_BYTES_WITHOUT_NONCE / 4); ++i)
			dst[i] = htobe32(src[i]);
	} else {
		/* Empty work is allowed only for the "purge" (slot = 0) operation */
		if (0 != slot) {
			applog(LOG_ERR, "%s[%d:%d] knc_titan_set_work: Invalid work", repr, die, core);
			return false;
		}
	}

	rxbuf = spi_transfer(spi, &set_work_cmd_aligned[3], send_size, transfer_size, 2 + KNC_TITAN_NONCES_PER_REPORT * 5, &errors, work_accepted);
	if (NULL == rxbuf) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_set_work: Unrecognized error", repr, die, core);
		return false;
	}
	if (0 != errors) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_set_work: Communication failed, errors = 0x%X", repr, die, core, errors);
		return false;
	}
	knc_titan_parse_get_report(&rxbuf[4], report);
	return true;
}

bool knc_titan_get_report(const char *repr, struct spi_port * const spi, struct titan_report *report, int die, int core)
{
	uint8_t get_report_cmd[] = {KNC_ASIC_CMD_REPORT, die, (core >> 8) & 0xFF, core & 0xFF};
	const int send_size = sizeof(get_report_cmd);
	const int transfer_size = send_size + 2 + KNC_TITAN_NONCES_PER_REPORT * 5 + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE;
	uint8_t *rxbuf;
	uint32_t errors;
	bool unused;

	rxbuf = spi_transfer(spi, get_report_cmd, send_size, transfer_size, 2 + KNC_TITAN_NONCES_PER_REPORT * 5, &errors, &unused);
	if (NULL == rxbuf) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_get_report: Unrecognized error", repr, die, core);
		return false;
	}
	if (0 != errors) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_get_report: Communication failed, errors = 0x%X", repr, die, core, errors);
		return false;
	}
	knc_titan_parse_get_report(&rxbuf[4], report);
	return true;
}

bool knc_titan_setup_core(const char *repr, struct spi_port * const spi, struct titan_setup_core_params *params, int die, int core)
{
	/* The size of command is the same as for set_work */
	uint8_t setup_core_cmd[SETWORK_CMD_SIZE] = {
		KNC_ASIC_CMD_SETUP_CORE,
		die,
		(core >> 8) & 0xFF,
		core & 0xFF,
		/* next follows padding and data */
	};
	const int send_size = sizeof(setup_core_cmd);
	const int transfer_size = send_size + CRC32_SIZE + SPI_RESPONSE_TRAILER_SIZE;
	uint8_t *rxbuf;
	uint32_t errors;
	bool unused;
	uint32_t *src, *dst;
	int i;
	struct titan_packed_core_params {
		/* WORD [0] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t padding			:26;
		uint32_t bad_address_mask_0_6msb	:6;
#else
		uint32_t bad_address_mask_0_6msb	:6;
		uint32_t padding			:26;
#endif
		/* WORD [1] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t bad_address_mask_0_4lsb	:4;
		uint32_t bad_address_mask_1		:10;
		uint32_t bad_address_match_0		:10;
		uint32_t bad_address_match_1_8msb	:8;
#else
		uint32_t bad_address_match_1_8msb	:8;
		uint32_t bad_address_match_0		:10;
		uint32_t bad_address_mask_1		:10;
		uint32_t bad_address_mask_0_4lsb	:4;
#endif
		/* WORD [2] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t bad_address_match_1_2lsb	:2;
		uint32_t difficulty			:6;
		uint32_t thread_enable			:8;
		uint32_t thread_base_address_0		:10;
		uint32_t thread_base_address_1_6msb	:6;
#else
		uint32_t thread_base_address_1_6msb	:6;
		uint32_t thread_base_address_0		:10;
		uint32_t thread_enable			:8;
		uint32_t difficulty			:6;
		uint32_t bad_address_match_1_2lsb	:2;
#endif
		/* WORD [3] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t thread_base_address_1_4lsb	:4;
		uint32_t thread_base_address_2		:10;
		uint32_t thread_base_address_3		:10;
		uint32_t thread_base_address_4_8msb	:8;
#else
		uint32_t thread_base_address_4_8msb	:8;
		uint32_t thread_base_address_3		:10;
		uint32_t thread_base_address_2		:10;
		uint32_t thread_base_address_1_4lsb	:4;
#endif
		/* WORD [4] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t thread_base_address_4_2lsb	:2;
		uint32_t thread_base_address_5		:10;
		uint32_t thread_base_address_6		:10;
		uint32_t thread_base_address_7		:10;
#else
		uint32_t thread_base_address_7		:10;
		uint32_t thread_base_address_6		:10;
		uint32_t thread_base_address_5		:10;
		uint32_t thread_base_address_4_2lsb	:2;
#endif
		/* WORD [5] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t lookup_gap_mask_0		:10;
		uint32_t lookup_gap_mask_1		:10;
		uint32_t lookup_gap_mask_2		:10;
		uint32_t lookup_gap_mask_3_2msb		:2;
#else
		uint32_t lookup_gap_mask_3_2msb		:2;
		uint32_t lookup_gap_mask_2		:10;
		uint32_t lookup_gap_mask_1		:10;
		uint32_t lookup_gap_mask_0		:10;
#endif
		/* WORD [6] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t lookup_gap_mask_3_8lsb		:8;
		uint32_t lookup_gap_mask_4		:10;
		uint32_t lookup_gap_mask_5		:10;
		uint32_t lookup_gap_mask_6_4msb		:4;
#else
		uint32_t lookup_gap_mask_6_4msb		:4;
		uint32_t lookup_gap_mask_5		:10;
		uint32_t lookup_gap_mask_4		:10;
		uint32_t lookup_gap_mask_3_8lsb		:8;
#endif
		/* WORD [7] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t lookup_gap_mask_6_6lsb		:6;
		uint32_t lookup_gap_mask_7		:10;
		uint32_t N_mask_0			:10;
		uint32_t N_mask_1_6msb			:6;
#else
		uint32_t N_mask_1_6msb			:6;
		uint32_t N_mask_0			:10;
		uint32_t lookup_gap_mask_7		:10;
		uint32_t lookup_gap_mask_6_6lsb		:6;
#endif
		/* WORD [8] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t N_mask_1_4lsb			:4;
		uint32_t N_mask_2			:10;
		uint32_t N_mask_3			:10;
		uint32_t N_mask_4_8msb			:8;
#else
		uint32_t N_mask_4_8msb			:8;
		uint32_t N_mask_3			:10;
		uint32_t N_mask_2			:10;
		uint32_t N_mask_1_4lsb			:4;
#endif
		/* WORD [9] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t N_mask_4_2lsb			:2;
		uint32_t N_mask_5			:10;
		uint32_t N_mask_6			:10;
		uint32_t N_mask_7			:10;
#else
		uint32_t N_mask_7			:10;
		uint32_t N_mask_6			:10;
		uint32_t N_mask_5			:10;
		uint32_t N_mask_4_2lsb			:2;
#endif
		/* WORD [10] */
#if (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
		uint32_t N_shift_0			:4;
		uint32_t N_shift_1			:4;
		uint32_t N_shift_2			:4;
		uint32_t N_shift_3			:4;
		uint32_t N_shift_4			:4;
		uint32_t N_shift_5			:4;
		uint32_t N_shift_6			:4;
		uint32_t N_shift_7			:4;
#else
		uint32_t N_shift_7			:4;
		uint32_t N_shift_6			:4;
		uint32_t N_shift_5			:4;
		uint32_t N_shift_4			:4;
		uint32_t N_shift_3			:4;
		uint32_t N_shift_2			:4;
		uint32_t N_shift_1			:4;
		uint32_t N_shift_0			:4;
#endif
		/* WORD [11] */
		uint32_t nonce_top;
		/* WORD [12] */
		uint32_t nonce_bottom;
	} __attribute__((packed)) packed_params;

	packed_params.padding = 0;
	packed_params.bad_address_mask_0_6msb = (params->bad_address_mask[0] >> 4) & 0x03F;
	packed_params.bad_address_mask_0_4lsb = params->bad_address_mask[0] & 0x00F;
	packed_params.bad_address_mask_1 = params->bad_address_mask[1];
	packed_params.bad_address_match_0 = params->bad_address_match[0];
	packed_params.bad_address_match_1_8msb = (params->bad_address_match[1] >> 2) & 0x0FF;
	packed_params.bad_address_match_1_2lsb = params->bad_address_match[1] & 0x003;
	packed_params.difficulty = params->difficulty;
	packed_params.thread_enable = params->thread_enable;
	packed_params.thread_base_address_0 = params->thread_base_address[0];
	packed_params.thread_base_address_1_6msb = (params->thread_base_address[1] >> 4) & 0x03F;
	packed_params.thread_base_address_1_4lsb = params->thread_base_address[1] & 0x00F;
	packed_params.thread_base_address_2 = params->thread_base_address[2];
	packed_params.thread_base_address_3 = params->thread_base_address[3];
	packed_params.thread_base_address_4_8msb = (params->thread_base_address[4] >> 2) & 0x0FF;
	packed_params.thread_base_address_4_2lsb = params->thread_base_address[4] & 0x003;
	packed_params.thread_base_address_5 = params->thread_base_address[5];
	packed_params.thread_base_address_6 = params->thread_base_address[6];
	packed_params.thread_base_address_7 = params->thread_base_address[7];
	packed_params.lookup_gap_mask_0 = params->lookup_gap_mask[0];
	packed_params.lookup_gap_mask_1 = params->lookup_gap_mask[1];
	packed_params.lookup_gap_mask_2 = params->lookup_gap_mask[2];
	packed_params.lookup_gap_mask_3_2msb = (params->lookup_gap_mask[3] >> 8) & 0x003;
	packed_params.lookup_gap_mask_3_8lsb = params->lookup_gap_mask[3] & 0x0FF;
	packed_params.lookup_gap_mask_4 = params->lookup_gap_mask[4];
	packed_params.lookup_gap_mask_5 = params->lookup_gap_mask[5];
	packed_params.lookup_gap_mask_6_4msb = (params->lookup_gap_mask[6] >> 6) & 0x00F;
	packed_params.lookup_gap_mask_6_6lsb = params->lookup_gap_mask[6] & 0x03F;
	packed_params.lookup_gap_mask_7 = params->lookup_gap_mask[7];
	packed_params.N_mask_0 = params->N_mask[0];
	packed_params.N_mask_1_6msb = (params->N_mask[1] >> 4) & 0x03F;
	packed_params.N_mask_1_4lsb = params->N_mask[1] & 0x00F;
	packed_params.N_mask_2 = params->N_mask[2];
	packed_params.N_mask_3 = params->N_mask[3];
	packed_params.N_mask_4_8msb = (params->N_mask[4] >> 2) & 0x0FF;
	packed_params.N_mask_4_2lsb = params->N_mask[4] & 0x003;
	packed_params.N_mask_5 = params->N_mask[5];
	packed_params.N_mask_6 = params->N_mask[6];
	packed_params.N_mask_7 = params->N_mask[7];
	packed_params.N_shift_0 = params->N_shift[0];
	packed_params.N_shift_1 = params->N_shift[1];
	packed_params.N_shift_2 = params->N_shift[2];
	packed_params.N_shift_3 = params->N_shift[3];
	packed_params.N_shift_4 = params->N_shift[4];
	packed_params.N_shift_5 = params->N_shift[5];
	packed_params.N_shift_6 = params->N_shift[6];
	packed_params.N_shift_7 = params->N_shift[7];
	packed_params.nonce_top = params->nonce_top;
	packed_params.nonce_bottom = params->nonce_bottom;

	src = (uint32_t *)&packed_params;
	dst = (uint32_t *)(&setup_core_cmd[send_size - sizeof(packed_params)]);
	for (i = 0; i < (sizeof(packed_params) / 4); ++i)
		dst[i] = htobe32(src[i]);

	rxbuf = spi_transfer(spi, setup_core_cmd, send_size, transfer_size, 0, &errors, &unused);
	if (NULL == rxbuf) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_setup_core: Unrecognized error", repr, die, core);
		return false;
	}
	if (0 != errors) {
		applog(LOG_ERR, "%s[%d:%d] knc_titan_setup_core: Communication failed, errors = 0x%X", repr, die, core, errors);
		return false;
	}
	return true;
}