/*
   * SPI flash operations
   *
   * Copyright (C) 2008 Atmel Corporation
   * Copyright (C) 2010 Reinhard Meyer, EMK Elektronik
   * Copyright (C) 2013 Jagannadha Sutradharudu Teki, Xilinx Inc.
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  #include <common.h>

  #include <malloc.h>

  #include <spi.h>
  #include <spi_flash.h>
  #include <watchdog.h>

  #include "sf_internal.h"

  
  static void spi_flash_addr(u32 addr, u8 *cmd)
  {
  	/* cmd[0] is actual command */
  	cmd[1] = addr >> 16;
  	cmd[2] = addr >> 8;
  	cmd[3] = addr >> 0;
  }

  int spi_flash_cmd_read_status(struct spi_flash *flash, u8 *rs)

  {

  	int ret;

  	u8 cmd;

  	cmd = CMD_READ_STATUS;
  	ret = spi_flash_read_common(flash, &cmd, 1, rs, 1);

  	if (ret < 0) {

  		debug("SF: fail to read status register
  ");

  		return ret;
  	}
  
  	return 0;
  }

  int spi_flash_cmd_write_status(struct spi_flash *flash, u8 ws)

  {

  	u8 cmd;
  	int ret;

  	cmd = CMD_WRITE_STATUS;

  	ret = spi_flash_write_common(flash, &cmd, 1, &ws, 1);

  	if (ret < 0) {

  		debug("SF: fail to write status register
  ");

  		return ret;
  	}

  	return 0;

  }

  #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)

  int spi_flash_cmd_read_config(struct spi_flash *flash, u8 *rc)

  {

  	int ret;

  	u8 cmd;

  	cmd = CMD_READ_CONFIG;
  	ret = spi_flash_read_common(flash, &cmd, 1, rc, 1);

  	if (ret < 0) {

  		debug("SF: fail to read config register
  ");

  		return ret;
  	}
  
  	return 0;
  }

  int spi_flash_cmd_write_config(struct spi_flash *flash, u8 wc)

  {

  	u8 data[2];

  	u8 cmd;
  	int ret;

  	ret = spi_flash_cmd_read_status(flash, &data[0]);
  	if (ret < 0)

  		return ret;

  	cmd = CMD_WRITE_STATUS;
  	data[1] = wc;
  	ret = spi_flash_write_common(flash, &cmd, 1, &data, 2);
  	if (ret) {
  		debug("SF: fail to write config register
  ");
  		return ret;

  	}

  	return 0;

  }
  #endif

  #ifdef CONFIG_SPI_FLASH_BAR

  static int spi_flash_cmd_bankaddr_write(struct spi_flash *flash, u8 bank_sel)

  {
  	u8 cmd;
  	int ret;
  
  	if (flash->bank_curr == bank_sel) {
  		debug("SF: not require to enable bank%d
  ", bank_sel);
  		return 0;
  	}
  
  	cmd = flash->bank_write_cmd;
  	ret = spi_flash_write_common(flash, &cmd, 1, &bank_sel, 1);
  	if (ret < 0) {
  		debug("SF: fail to write bank register
  ");
  		return ret;
  	}
  	flash->bank_curr = bank_sel;
  
  	return 0;
  }

  
  static int spi_flash_bank(struct spi_flash *flash, u32 offset)
  {
  	u8 bank_sel;
  	int ret;

  	bank_sel = offset / (SPI_FLASH_16MB_BOUN << flash->shift);

  
  	ret = spi_flash_cmd_bankaddr_write(flash, bank_sel);
  	if (ret) {
  		debug("SF: fail to set bank%d
  ", bank_sel);
  		return ret;
  	}

  	return bank_sel;

  }

  #endif

  #ifdef CONFIG_SF_DUAL_FLASH

  static void spi_flash_dual_flash(struct spi_flash *flash, u32 *addr)
  {
  	switch (flash->dual_flash) {
  	case SF_DUAL_STACKED_FLASH:
  		if (*addr >= (flash->size >> 1)) {
  			*addr -= flash->size >> 1;
  			flash->spi->flags |= SPI_XFER_U_PAGE;
  		} else {
  			flash->spi->flags &= ~SPI_XFER_U_PAGE;
  		}
  		break;

  	case SF_DUAL_PARALLEL_FLASH:
  		*addr >>= flash->shift;
  		break;

  	default:
  		debug("SF: Unsupported dual_flash=%d
  ", flash->dual_flash);
  		break;
  	}
  }

  #endif

  int spi_flash_cmd_wait_ready(struct spi_flash *flash, unsigned long timeout)
  {
  	struct spi_slave *spi = flash->spi;
  	unsigned long timebase;

  	unsigned long flags = SPI_XFER_BEGIN;

  	int ret;
  	u8 status;
  	u8 check_status = 0x0;
  	u8 poll_bit = STATUS_WIP;
  	u8 cmd = flash->poll_cmd;
  
  	if (cmd == CMD_FLAG_STATUS) {
  		poll_bit = STATUS_PEC;
  		check_status = poll_bit;
  	}

  #ifdef CONFIG_SF_DUAL_FLASH

  	if (spi->flags & SPI_XFER_U_PAGE)
  		flags |= SPI_XFER_U_PAGE;

  #endif

  	ret = spi_xfer(spi, 8, &cmd, NULL, flags);

  	if (ret) {
  		debug("SF: fail to read %s status register
  ",
  		      cmd == CMD_READ_STATUS ? "read" : "flag");
  		return ret;
  	}
  
  	timebase = get_timer(0);
  	do {
  		WATCHDOG_RESET();
  
  		ret = spi_xfer(spi, 8, NULL, &status, 0);
  		if (ret)
  			return -1;
  
  		if ((status & poll_bit) == check_status)
  			break;
  
  	} while (get_timer(timebase) < timeout);
  
  	spi_xfer(spi, 0, NULL, NULL, SPI_XFER_END);
  
  	if ((status & poll_bit) == check_status)
  		return 0;
  
  	/* Timed out */
  	debug("SF: time out!
  ");
  	return -1;
  }
  
  int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
  		size_t cmd_len, const void *buf, size_t buf_len)
  {
  	struct spi_slave *spi = flash->spi;
  	unsigned long timeout = SPI_FLASH_PROG_TIMEOUT;
  	int ret;
  
  	if (buf == NULL)
  		timeout = SPI_FLASH_PAGE_ERASE_TIMEOUT;
  
  	ret = spi_claim_bus(flash->spi);
  	if (ret) {
  		debug("SF: unable to claim SPI bus
  ");
  		return ret;
  	}
  
  	ret = spi_flash_cmd_write_enable(flash);
  	if (ret < 0) {
  		debug("SF: enabling write failed
  ");
  		return ret;
  	}
  
  	ret = spi_flash_cmd_write(spi, cmd, cmd_len, buf, buf_len);
  	if (ret < 0) {
  		debug("SF: write cmd failed
  ");
  		return ret;
  	}
  
  	ret = spi_flash_cmd_wait_ready(flash, timeout);
  	if (ret < 0) {
  		debug("SF: write %s timed out
  ",
  		      timeout == SPI_FLASH_PROG_TIMEOUT ?
  			"program" : "page erase");
  		return ret;
  	}
  
  	spi_release_bus(spi);
  
  	return ret;
  }

  int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)

  {

  	u32 erase_size, erase_addr;

  	u8 cmd[SPI_FLASH_CMD_LEN];

  	int ret = -1;

  	erase_size = flash->erase_size;

  	if (offset % erase_size || len % erase_size) {
  		debug("SF: Erase offset/length not multiple of erase size
  ");
  		return -1;
  	}

  	cmd[0] = flash->erase_cmd;

  	while (len) {

  		erase_addr = offset;

  #ifdef CONFIG_SF_DUAL_FLASH

  		if (flash->dual_flash > SF_SINGLE_FLASH)
  			spi_flash_dual_flash(flash, &erase_addr);

  #endif

  #ifdef CONFIG_SPI_FLASH_BAR

  		ret = spi_flash_bank(flash, erase_addr);

  		if (ret < 0)

  			return ret;

  #endif

  		spi_flash_addr(erase_addr, cmd);

  
  		debug("SF: erase %2x %2x %2x %2x (%x)
  ", cmd[0], cmd[1],

  		      cmd[2], cmd[3], erase_addr);

  
  		ret = spi_flash_write_common(flash, cmd, sizeof(cmd), NULL, 0);
  		if (ret < 0) {
  			debug("SF: erase failed
  ");
  			break;
  		}
  
  		offset += erase_size;
  		len -= erase_size;
  	}
  
  	return ret;
  }

  int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,

  		size_t len, const void *buf)
  {
  	unsigned long byte_addr, page_size;

  	u32 write_addr;

  	size_t chunk_len, actual;

  	u8 cmd[SPI_FLASH_CMD_LEN];

  	int ret = -1;
  
  	page_size = flash->page_size;

  	cmd[0] = flash->write_cmd;

  	for (actual = 0; actual < len; actual += chunk_len) {

  		write_addr = offset;

  #ifdef CONFIG_SF_DUAL_FLASH

  		if (flash->dual_flash > SF_SINGLE_FLASH)
  			spi_flash_dual_flash(flash, &write_addr);

  #endif

  #ifdef CONFIG_SPI_FLASH_BAR

  		ret = spi_flash_bank(flash, write_addr);

  		if (ret < 0)

  			return ret;

  #endif
  		byte_addr = offset % page_size;
  		chunk_len = min(len - actual, page_size - byte_addr);
  
  		if (flash->spi->max_write_size)
  			chunk_len = min(chunk_len, flash->spi->max_write_size);

  		spi_flash_addr(write_addr, cmd);

  		debug("SF: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zu
  ",

  		      buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
  
  		ret = spi_flash_write_common(flash, cmd, sizeof(cmd),
  					buf + actual, chunk_len);
  		if (ret < 0) {
  			debug("SF: write failed
  ");
  			break;
  		}
  
  		offset += chunk_len;
  	}
  
  	return ret;
  }
  
  int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
  		size_t cmd_len, void *data, size_t data_len)
  {
  	struct spi_slave *spi = flash->spi;
  	int ret;
  
  	ret = spi_claim_bus(flash->spi);
  	if (ret) {
  		debug("SF: unable to claim SPI bus
  ");
  		return ret;
  	}
  
  	ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len);
  	if (ret < 0) {
  		debug("SF: read cmd failed
  ");
  		return ret;
  	}
  
  	spi_release_bus(spi);
  
  	return ret;
  }

  int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,

  		size_t len, void *data)
  {

  	u8 *cmd, cmdsz;

  	u32 remain_len, read_len, read_addr;

  	int bank_sel = 0;

  	int ret = -1;
  
  	/* Handle memory-mapped SPI */
  	if (flash->memory_map) {

  		ret = spi_claim_bus(flash->spi);
  		if (ret) {
  			debug("SF: unable to claim SPI bus
  ");
  			return ret;
  		}

  		spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP);

  		memcpy(data, flash->memory_map + offset, len);

  		spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP_END);

  		spi_release_bus(flash->spi);

  		return 0;
  	}

  	cmdsz = SPI_FLASH_CMD_LEN + flash->dummy_byte;
  	cmd = malloc(cmdsz);
  	memset(cmd, 0, cmdsz);

  	cmd[0] = flash->read_cmd;

  	while (len) {

  		read_addr = offset;

  #ifdef CONFIG_SF_DUAL_FLASH

  		if (flash->dual_flash > SF_SINGLE_FLASH)
  			spi_flash_dual_flash(flash, &read_addr);

  #endif

  #ifdef CONFIG_SPI_FLASH_BAR

  		bank_sel = spi_flash_bank(flash, read_addr);

  		if (bank_sel < 0)

  			return ret;

  #endif

  		remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
  				(bank_sel + 1)) - offset;

  		if (len < remain_len)
  			read_len = len;
  		else
  			read_len = remain_len;

  		spi_flash_addr(read_addr, cmd);

  		ret = spi_flash_read_common(flash, cmd, cmdsz, data, read_len);

  		if (ret < 0) {
  			debug("SF: read failed
  ");
  			break;
  		}
  
  		offset += read_len;
  		len -= read_len;
  		data += read_len;
  	}
  
  	return ret;
  }

  
  #ifdef CONFIG_SPI_FLASH_SST
  static int sst_byte_write(struct spi_flash *flash, u32 offset, const void *buf)
  {
  	int ret;
  	u8 cmd[4] = {
  		CMD_SST_BP,
  		offset >> 16,
  		offset >> 8,
  		offset,
  	};
  
  	debug("BP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }
  ",
  	      spi_w8r8(flash->spi, CMD_READ_STATUS), buf, cmd[0], offset);
  
  	ret = spi_flash_cmd_write_enable(flash);
  	if (ret)
  		return ret;
  
  	ret = spi_flash_cmd_write(flash->spi, cmd, sizeof(cmd), buf, 1);
  	if (ret)
  		return ret;
  
  	return spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
  }
  
  int sst_write_wp(struct spi_flash *flash, u32 offset, size_t len,
  		const void *buf)
  {
  	size_t actual, cmd_len;
  	int ret;
  	u8 cmd[4];
  
  	ret = spi_claim_bus(flash->spi);
  	if (ret) {
  		debug("SF: Unable to claim SPI bus
  ");
  		return ret;
  	}
  
  	/* If the data is not word aligned, write out leading single byte */
  	actual = offset % 2;
  	if (actual) {
  		ret = sst_byte_write(flash, offset, buf);
  		if (ret)
  			goto done;
  	}
  	offset += actual;
  
  	ret = spi_flash_cmd_write_enable(flash);
  	if (ret)
  		goto done;
  
  	cmd_len = 4;
  	cmd[0] = CMD_SST_AAI_WP;
  	cmd[1] = offset >> 16;
  	cmd[2] = offset >> 8;
  	cmd[3] = offset;
  
  	for (; actual < len - 1; actual += 2) {
  		debug("WP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }
  ",
  		      spi_w8r8(flash->spi, CMD_READ_STATUS), buf + actual,
  		      cmd[0], offset);
  
  		ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len,
  					buf + actual, 2);
  		if (ret) {
  			debug("SF: sst word program failed
  ");
  			break;
  		}
  
  		ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
  		if (ret)
  			break;
  
  		cmd_len = 1;
  		offset += 2;
  	}
  
  	if (!ret)
  		ret = spi_flash_cmd_write_disable(flash);
  
  	/* If there is a single trailing byte, write it out */
  	if (!ret && actual != len)
  		ret = sst_byte_write(flash, offset, buf + actual);
  
   done:
  	debug("SF: sst: program %s %zu bytes @ 0x%zx
  ",
  	      ret ? "failure" : "success", len, offset - actual);
  
  	spi_release_bus(flash->spi);
  	return ret;
  }
  #endif