drivers/misc/mxc_ocotp.c - platform/external/u-boot - Gitiles

 /*
  * (C) Copyright 2013 ADVANSEE
  * Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
  *
  * Based on Dirk Behme's
  * https://github.com/dirkbehme/u-boot-imx6/blob/28b17e9/drivers/misc/imx_otp.c,
  * which is based on Freescale's
  * http://git.freescale.com/git/cgit.cgi/imx/uboot-imx.git/tree/drivers/misc/imx_otp.c?h=imx_v2009.08_1.1.0&id=9aa74e6,
  * which is:
  * Copyright (C) 2011 Freescale Semiconductor, Inc.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

 #include <common.h>
 #include <fuse.h>
 #include <linux/errno.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/imx-regs.h>
 #include <asm/mach-imx/sys_proto.h>

 #define BO_CTRL_WR_UNLOCK		16
 #define BM_CTRL_WR_UNLOCK		0xffff0000
 #define BV_CTRL_WR_UNLOCK_KEY		0x3e77
 #define BM_CTRL_ERROR			0x00000200
 #define BM_CTRL_BUSY			0x00000100
 #define BO_CTRL_ADDR			0
 #ifdef CONFIG_MX7
 #define BM_CTRL_ADDR                    0x0000000f
 #define BM_CTRL_RELOAD                  0x00000400
 #elif defined(CONFIG_MX7ULP)
 #define BM_CTRL_ADDR                    0x000000FF
 #define BM_CTRL_RELOAD                  0x00000400
 #define BM_OUT_STATUS_DED				0x00000400
 #define BM_OUT_STATUS_LOCKED			0x00000800
 #define BM_OUT_STATUS_PROGFAIL			0x00001000
 #elif defined(CONFIG_MX8M)
 #define BM_CTRL_ADDR			0x000000ff
 #else
 #define BM_CTRL_ADDR			0x0000007f
 #endif

 #ifdef CONFIG_MX7
 #define BO_TIMING_FSOURCE               12
 #define BM_TIMING_FSOURCE               0x0007f000
 #define BV_TIMING_FSOURCE_NS            1001
 #define BO_TIMING_PROG                  0
 #define BM_TIMING_PROG                  0x00000fff
 #define BV_TIMING_PROG_US               10
 #else
 #define BO_TIMING_STROBE_READ		16
 #define BM_TIMING_STROBE_READ		0x003f0000
 #define BV_TIMING_STROBE_READ_NS	37
 #define BO_TIMING_RELAX			12
 #define BM_TIMING_RELAX			0x0000f000
 #define BV_TIMING_RELAX_NS		17
 #define BO_TIMING_STROBE_PROG		0
 #define BM_TIMING_STROBE_PROG		0x00000fff
 #define BV_TIMING_STROBE_PROG_US	10
 #endif

 #define BM_READ_CTRL_READ_FUSE		0x00000001

 #define BF(value, field)		(((value) << BO_##field) & BM_##field)

 #define WRITE_POSTAMBLE_US		2

 #if defined(CONFIG_MX6) || defined(CONFIG_VF610)
 #define FUSE_BANK_SIZE	0x80
 #ifdef CONFIG_MX6SL
 #define FUSE_BANKS	8
 #elif defined(CONFIG_MX6ULL) || defined(CONFIG_MX6SLL)
 #define FUSE_BANKS	9
 #else
 #define FUSE_BANKS	16
 #endif
 #elif defined CONFIG_MX7
 #define FUSE_BANK_SIZE	0x40
 #define FUSE_BANKS	16
 #elif defined(CONFIG_MX7ULP)
 #define FUSE_BANK_SIZE	0x80
 #define FUSE_BANKS	31
 #elif defined(CONFIG_MX8M)
 #define FUSE_BANK_SIZE	0x40
 #define FUSE_BANKS	64
 #else
 #error "Unsupported architecture\n"
 #endif

 #if defined(CONFIG_MX6)

 /*
  * There is a hole in shadow registers address map of size 0x100
  * between bank 5 and bank 6 on iMX6QP, iMX6DQ, iMX6SDL, iMX6SX,
  * iMX6UL, i.MX6ULL and i.MX6SLL.
  * Bank 5 ends at 0x6F0 and Bank 6 starts at 0x800. When reading the fuses,
  * we should account for this hole in address space.
  *
  * Similar hole exists between bank 14 and bank 15 of size
  * 0x80 on iMX6QP, iMX6DQ, iMX6SDL and iMX6SX.
  * Note: iMX6SL has only 0-7 banks and there is no hole.
  * Note: iMX6UL doesn't have this one.
  *
  * This function is to covert user input to physical bank index.
  * Only needed when read fuse, because we use register offset, so
  * need to calculate real register offset.
  * When write, no need to consider hole, always use the bank/word
  * index from fuse map.
  */
 u32 fuse_bank_physical(int index)
 {
 	u32 phy_index;

 	if (is_mx6sl() || is_mx7ulp()) {
 		phy_index = index;
 	} else if (is_mx6ul() || is_mx6ull() || is_mx6sll()) {
 		if ((is_mx6ull() || is_mx6sll()) && index == 8)
 			index = 7;

 		if (index >= 6)
 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
 		else
 			phy_index = index;
 	} else {
 		if (index >= 15)
 			phy_index = fuse_bank_physical(14) + (index - 15) + 2;
 		else if (index >= 6)
 			phy_index = fuse_bank_physical(5) + (index - 6) + 3;
 		else
 			phy_index = index;
 	}
 	return phy_index;
 }

 u32 fuse_word_physical(u32 bank, u32 word_index)
 {
 	if (is_mx6ull() || is_mx6sll()) {
 		if (bank == 8)
 			word_index = word_index + 4;
 	}

 	return word_index;
 }
 #else
 u32 fuse_bank_physical(int index)
 {
 	return index;
 }

 u32 fuse_word_physical(u32 bank, u32 word_index)
 {
 	return word_index;
 }

 #endif

 static void wait_busy(struct ocotp_regs *regs, unsigned int delay_us)
 {
 	while (readl(&regs->ctrl) & BM_CTRL_BUSY)
 		udelay(delay_us);
 }

 static void clear_error(struct ocotp_regs *regs)
 {
 	writel(BM_CTRL_ERROR, &regs->ctrl_clr);
 }

 static int prepare_access(struct ocotp_regs **regs, u32 bank, u32 word,
 				int assert, const char *caller)
 {
 	*regs = (struct ocotp_regs *)OCOTP_BASE_ADDR;

 	if (bank >= FUSE_BANKS ||
 	    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 2 ||
 	    !assert) {
 		printf("mxc_ocotp %s(): Invalid argument\n", caller);
 		return -EINVAL;
 	}

 	if (is_mx6ull() || is_mx6sll()) {
 		if ((bank == 7 || bank == 8) &&
 		    word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 3) {
 			printf("mxc_ocotp %s(): Invalid argument\n", caller);
 			return -EINVAL;
 		}
 	}

 	enable_ocotp_clk(1);

 	wait_busy(*regs, 1);
 	clear_error(*regs);

 	return 0;
 }

 static int finish_access(struct ocotp_regs *regs, const char *caller)
 {
 	u32 err;

 	err = !!(readl(&regs->ctrl) & BM_CTRL_ERROR);
 	clear_error(regs);

 #ifdef CONFIG_MX7ULP
 	/* Need to power down the OTP memory */
 	writel(1, &regs->pdn);
 #endif
 	if (err) {
 		printf("mxc_ocotp %s(): Access protect error\n", caller);
 		return -EIO;
 	}

 	return 0;
 }

 static int prepare_read(struct ocotp_regs **regs, u32 bank, u32 word, u32 *val,
 			const char *caller)
 {
 	return prepare_access(regs, bank, word, val != NULL, caller);
 }

 int fuse_read(u32 bank, u32 word, u32 *val)
 {
 	struct ocotp_regs *regs;
 	int ret;
 	u32 phy_bank;
 	u32 phy_word;

 	ret = prepare_read(&regs, bank, word, val, __func__);
 	if (ret)
 		return ret;

 	phy_bank = fuse_bank_physical(bank);
 	phy_word = fuse_word_physical(bank, word);

 	*val = readl(&regs->bank[phy_bank].fuse_regs[phy_word << 2]);

 #ifdef CONFIG_MX7ULP
 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
 		return -EIO;
 	}
 #endif
 	return finish_access(regs, __func__);
 }

 #ifdef CONFIG_MX7
 static void set_timing(struct ocotp_regs *regs)
 {
 	u32 ipg_clk;
 	u32 fsource, prog;
 	u32 timing;

 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);

 	fsource = DIV_ROUND_UP((ipg_clk / 1000) * BV_TIMING_FSOURCE_NS,
 			+       1000000) + 1;
 	prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_PROG_US, 1000000) + 1;

 	timing = BF(fsource, TIMING_FSOURCE) | BF(prog, TIMING_PROG);

 	clrsetbits_le32(&regs->timing, BM_TIMING_FSOURCE | BM_TIMING_PROG,
 			timing);
 }
 #elif defined(CONFIG_MX7ULP)
 static void set_timing(struct ocotp_regs *regs)
 {
 	/* No timing set for MX7ULP */
 }

 #else
 static void set_timing(struct ocotp_regs *regs)
 {
 	u32 ipg_clk;
 	u32 relax, strobe_read, strobe_prog;
 	u32 timing;

 	ipg_clk = mxc_get_clock(MXC_IPG_CLK);

 	relax = DIV_ROUND_UP(ipg_clk * BV_TIMING_RELAX_NS, 1000000000) - 1;
 	strobe_read = DIV_ROUND_UP(ipg_clk * BV_TIMING_STROBE_READ_NS,
 					1000000000) + 2 * (relax + 1) - 1;
 	strobe_prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_STROBE_PROG_US,
 						1000000) + 2 * (relax + 1) - 1;

 	timing = BF(strobe_read, TIMING_STROBE_READ) |
 			BF(relax, TIMING_RELAX) |
 			BF(strobe_prog, TIMING_STROBE_PROG);

 	clrsetbits_le32(&regs->timing, BM_TIMING_STROBE_READ | BM_TIMING_RELAX |
 			BM_TIMING_STROBE_PROG, timing);
 }
 #endif

 static void setup_direct_access(struct ocotp_regs *regs, u32 bank, u32 word,
 				int write)
 {
 	u32 wr_unlock = write ? BV_CTRL_WR_UNLOCK_KEY : 0;
 #ifdef CONFIG_MX7
 	u32 addr = bank;
 #elif defined CONFIG_MX8M
 	u32 addr = bank << 2 | word;
 #else
 	u32 addr;
 	/* Bank 7 and Bank 8 only supports 4 words each for i.MX6ULL */
 	if ((is_mx6ull() || is_mx6sll()) && (bank > 7)) {
 		bank = bank - 1;
 		word += 4;
 	}
 	addr = bank << 3 | word;
 #endif

 	set_timing(regs);
 	clrsetbits_le32(&regs->ctrl, BM_CTRL_WR_UNLOCK | BM_CTRL_ADDR,
 			BF(wr_unlock, CTRL_WR_UNLOCK) |
 			BF(addr, CTRL_ADDR));
 }

 int fuse_sense(u32 bank, u32 word, u32 *val)
 {
 	struct ocotp_regs *regs;
 	int ret;

 	ret = prepare_read(&regs, bank, word, val, __func__);
 	if (ret)
 		return ret;

 	setup_direct_access(regs, bank, word, false);
 	writel(BM_READ_CTRL_READ_FUSE, &regs->read_ctrl);
 	wait_busy(regs, 1);
 #ifdef CONFIG_MX7
 	*val = readl((&regs->read_fuse_data0) + (word << 2));
 #else
 	*val = readl(&regs->read_fuse_data);
 #endif

 #ifdef CONFIG_MX7ULP
 	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
 		writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
 		printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
 		return -EIO;
 	}
 #endif

 	return finish_access(regs, __func__);
 }

 static int prepare_write(struct ocotp_regs **regs, u32 bank, u32 word,
 				const char *caller)
 {
 #ifdef CONFIG_MX7ULP
 	u32 val;
 	int ret;

 	/* Only bank 0 and 1 are redundancy mode, others are ECC mode */
 	if (bank != 0 && bank != 1) {
 		ret = fuse_sense(bank, word, &val);
 		if (ret)
 			return ret;

 		if (val != 0) {
 			printf("mxc_ocotp: The word has been programmed, no more write\n");
 			return -EPERM;
 		}
 	}
 #endif

 	return prepare_access(regs, bank, word, true, caller);
 }

 int fuse_prog(u32 bank, u32 word, u32 val)
 {
 	struct ocotp_regs *regs;
 	int ret;

 	ret = prepare_write(&regs, bank, word, __func__);
 	if (ret)
 		return ret;

 	setup_direct_access(regs, bank, word, true);
 #ifdef CONFIG_MX7
 	switch (word) {
 	case 0:
 		writel(0, &regs->data1);
 		writel(0, &regs->data2);
 		writel(0, &regs->data3);
 		writel(val, &regs->data0);
 		break;
 	case 1:
 		writel(val, &regs->data1);
 		writel(0, &regs->data2);
 		writel(0, &regs->data3);
 		writel(0, &regs->data0);
 		break;
 	case 2:
 		writel(0, &regs->data1);
 		writel(val, &regs->data2);
 		writel(0, &regs->data3);
 		writel(0, &regs->data0);
 		break;
 	case 3:
 		writel(0, &regs->data1);
 		writel(0, &regs->data2);
 		writel(val, &regs->data3);
 		writel(0, &regs->data0);
 		break;
 	}
 	wait_busy(regs, BV_TIMING_PROG_US);
 #else
 	writel(val, &regs->data);
 	wait_busy(regs, BV_TIMING_STROBE_PROG_US);
 #endif
 	udelay(WRITE_POSTAMBLE_US);

 #ifdef CONFIG_MX7ULP
 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
 		return -EIO;
 	}
 #endif

 	return finish_access(regs, __func__);
 }

 int fuse_override(u32 bank, u32 word, u32 val)
 {
 	struct ocotp_regs *regs;
 	int ret;
 	u32 phy_bank;
 	u32 phy_word;

 	ret = prepare_write(&regs, bank, word, __func__);
 	if (ret)
 		return ret;

 	phy_bank = fuse_bank_physical(bank);
 	phy_word = fuse_word_physical(bank, word);

 	writel(val, &regs->bank[phy_bank].fuse_regs[phy_word << 2]);

 #ifdef CONFIG_MX7ULP
 	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED)) {
 		writel((BM_OUT_STATUS_PROGFAIL | BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
 		printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
 		return -EIO;
 	}
 #endif

 	return finish_access(regs, __func__);
 }
	/*
	* (C) Copyright 2013 ADVANSEE
	* Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
	*
	* Based on Dirk Behme's
	* https://github.com/dirkbehme/u-boot-imx6/blob/28b17e9/drivers/misc/imx_otp.c,
	* which is based on Freescale's
	* http://git.freescale.com/git/cgit.cgi/imx/uboot-imx.git/tree/drivers/misc/imx_otp.c?h=imx_v2009.08_1.1.0&id=9aa74e6,
	* which is:
	* Copyright (C) 2011 Freescale Semiconductor, Inc.
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

	#include <common.h>
	#include <fuse.h>
	#include <linux/errno.h>
	#include <asm/io.h>
	#include <asm/arch/clock.h>
	#include <asm/arch/imx-regs.h>
	#include <asm/mach-imx/sys_proto.h>

	#define BO_CTRL_WR_UNLOCK 16
	#define BM_CTRL_WR_UNLOCK 0xffff0000
	#define BV_CTRL_WR_UNLOCK_KEY 0x3e77
	#define BM_CTRL_ERROR 0x00000200
	#define BM_CTRL_BUSY 0x00000100
	#define BO_CTRL_ADDR 0
	#ifdef CONFIG_MX7
	#define BM_CTRL_ADDR 0x0000000f
	#define BM_CTRL_RELOAD 0x00000400
	#elif defined(CONFIG_MX7ULP)
	#define BM_CTRL_ADDR 0x000000FF
	#define BM_CTRL_RELOAD 0x00000400
	#define BM_OUT_STATUS_DED 0x00000400
	#define BM_OUT_STATUS_LOCKED 0x00000800
	#define BM_OUT_STATUS_PROGFAIL 0x00001000
	#elif defined(CONFIG_MX8M)
	#define BM_CTRL_ADDR 0x000000ff
	#else
	#define BM_CTRL_ADDR 0x0000007f
	#endif

	#ifdef CONFIG_MX7
	#define BO_TIMING_FSOURCE 12
	#define BM_TIMING_FSOURCE 0x0007f000
	#define BV_TIMING_FSOURCE_NS 1001
	#define BO_TIMING_PROG 0
	#define BM_TIMING_PROG 0x00000fff
	#define BV_TIMING_PROG_US 10
	#else
	#define BO_TIMING_STROBE_READ 16
	#define BM_TIMING_STROBE_READ 0x003f0000
	#define BV_TIMING_STROBE_READ_NS 37
	#define BO_TIMING_RELAX 12
	#define BM_TIMING_RELAX 0x0000f000
	#define BV_TIMING_RELAX_NS 17
	#define BO_TIMING_STROBE_PROG 0
	#define BM_TIMING_STROBE_PROG 0x00000fff
	#define BV_TIMING_STROBE_PROG_US 10
	#endif

	#define BM_READ_CTRL_READ_FUSE 0x00000001

	#define BF(value, field) (((value) << BO_##field) & BM_##field)

	#define WRITE_POSTAMBLE_US 2

	#if defined(CONFIG_MX6) \|\| defined(CONFIG_VF610)
	#define FUSE_BANK_SIZE 0x80
	#ifdef CONFIG_MX6SL
	#define FUSE_BANKS 8
	#elif defined(CONFIG_MX6ULL) \|\| defined(CONFIG_MX6SLL)
	#define FUSE_BANKS 9
	#else
	#define FUSE_BANKS 16
	#endif
	#elif defined CONFIG_MX7
	#define FUSE_BANK_SIZE 0x40
	#define FUSE_BANKS 16
	#elif defined(CONFIG_MX7ULP)
	#define FUSE_BANK_SIZE 0x80
	#define FUSE_BANKS 31
	#elif defined(CONFIG_MX8M)
	#define FUSE_BANK_SIZE 0x40
	#define FUSE_BANKS 64
	#else
	#error "Unsupported architecture\n"
	#endif

	#if defined(CONFIG_MX6)

	/*
	* There is a hole in shadow registers address map of size 0x100
	* between bank 5 and bank 6 on iMX6QP, iMX6DQ, iMX6SDL, iMX6SX,
	* iMX6UL, i.MX6ULL and i.MX6SLL.
	* Bank 5 ends at 0x6F0 and Bank 6 starts at 0x800. When reading the fuses,
	* we should account for this hole in address space.
	*
	* Similar hole exists between bank 14 and bank 15 of size
	* 0x80 on iMX6QP, iMX6DQ, iMX6SDL and iMX6SX.
	* Note: iMX6SL has only 0-7 banks and there is no hole.
	* Note: iMX6UL doesn't have this one.
	*
	* This function is to covert user input to physical bank index.
	* Only needed when read fuse, because we use register offset, so
	* need to calculate real register offset.
	* When write, no need to consider hole, always use the bank/word
	* index from fuse map.
	*/
	u32 fuse_bank_physical(int index)
	{
	u32 phy_index;

	if (is_mx6sl() \|\| is_mx7ulp()) {
	phy_index = index;
	} else if (is_mx6ul() \|\| is_mx6ull() \|\| is_mx6sll()) {
	if ((is_mx6ull() \|\| is_mx6sll()) && index == 8)
	index = 7;

	if (index >= 6)
	phy_index = fuse_bank_physical(5) + (index - 6) + 3;
	else
	phy_index = index;
	} else {
	if (index >= 15)
	phy_index = fuse_bank_physical(14) + (index - 15) + 2;
	else if (index >= 6)
	phy_index = fuse_bank_physical(5) + (index - 6) + 3;
	else
	phy_index = index;
	}
	return phy_index;
	}

	u32 fuse_word_physical(u32 bank, u32 word_index)
	{
	if (is_mx6ull() \|\| is_mx6sll()) {
	if (bank == 8)
	word_index = word_index + 4;
	}

	return word_index;
	}
	#else
	u32 fuse_bank_physical(int index)
	{
	return index;
	}

	u32 fuse_word_physical(u32 bank, u32 word_index)
	{
	return word_index;
	}

	#endif

	static void wait_busy(struct ocotp_regs *regs, unsigned int delay_us)
	{
	while (readl(&regs->ctrl) & BM_CTRL_BUSY)
	udelay(delay_us);
	}

	static void clear_error(struct ocotp_regs *regs)
	{
	writel(BM_CTRL_ERROR, &regs->ctrl_clr);
	}

	static int prepare_access(struct ocotp_regs **regs, u32 bank, u32 word,
	int assert, const char *caller)
	{
	regs = (struct ocotp_regs )OCOTP_BASE_ADDR;

	if (bank >= FUSE_BANKS \|\|
	word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 2 \|\|
	!assert) {
	printf("mxc_ocotp %s(): Invalid argument\n", caller);
	return -EINVAL;
	}

	if (is_mx6ull() \|\| is_mx6sll()) {
	if ((bank == 7 \|\| bank == 8) &&
	word >= ARRAY_SIZE((*regs)->bank[0].fuse_regs) >> 3) {
	printf("mxc_ocotp %s(): Invalid argument\n", caller);
	return -EINVAL;
	}
	}

	enable_ocotp_clk(1);

	wait_busy(*regs, 1);
	clear_error(*regs);

	return 0;
	}

	static int finish_access(struct ocotp_regs regs, const char caller)
	{
	u32 err;

	err = !!(readl(&regs->ctrl) & BM_CTRL_ERROR);
	clear_error(regs);

	#ifdef CONFIG_MX7ULP
	/* Need to power down the OTP memory */
	writel(1, &regs->pdn);
	#endif
	if (err) {
	printf("mxc_ocotp %s(): Access protect error\n", caller);
	return -EIO;
	}

	return 0;
	}

	static int prepare_read(struct ocotp_regs *regs, u32 bank, u32 word, u32 val,
	const char *caller)
	{
	return prepare_access(regs, bank, word, val != NULL, caller);
	}

	int fuse_read(u32 bank, u32 word, u32 *val)
	{
	struct ocotp_regs *regs;
	int ret;
	u32 phy_bank;
	u32 phy_word;

	ret = prepare_read(&regs, bank, word, val, __func__);
	if (ret)
	return ret;

	phy_bank = fuse_bank_physical(bank);
	phy_word = fuse_word_physical(bank, word);

	*val = readl(&regs->bank[phy_bank].fuse_regs[phy_word << 2]);

	#ifdef CONFIG_MX7ULP
	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
	writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
	printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
	return -EIO;
	}
	#endif
	return finish_access(regs, __func__);
	}

	#ifdef CONFIG_MX7
	static void set_timing(struct ocotp_regs *regs)
	{
	u32 ipg_clk;
	u32 fsource, prog;
	u32 timing;

	ipg_clk = mxc_get_clock(MXC_IPG_CLK);

	fsource = DIV_ROUND_UP((ipg_clk / 1000) * BV_TIMING_FSOURCE_NS,
	+ 1000000) + 1;
	prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_PROG_US, 1000000) + 1;

	timing = BF(fsource, TIMING_FSOURCE) \| BF(prog, TIMING_PROG);

	clrsetbits_le32(&regs->timing, BM_TIMING_FSOURCE \| BM_TIMING_PROG,
	timing);
	}
	#elif defined(CONFIG_MX7ULP)
	static void set_timing(struct ocotp_regs *regs)
	{
	/* No timing set for MX7ULP */
	}

	#else
	static void set_timing(struct ocotp_regs *regs)
	{
	u32 ipg_clk;
	u32 relax, strobe_read, strobe_prog;
	u32 timing;

	ipg_clk = mxc_get_clock(MXC_IPG_CLK);

	relax = DIV_ROUND_UP(ipg_clk * BV_TIMING_RELAX_NS, 1000000000) - 1;
	strobe_read = DIV_ROUND_UP(ipg_clk * BV_TIMING_STROBE_READ_NS,
	1000000000) + 2 * (relax + 1) - 1;
	strobe_prog = DIV_ROUND_CLOSEST(ipg_clk * BV_TIMING_STROBE_PROG_US,
	1000000) + 2 * (relax + 1) - 1;

	timing = BF(strobe_read, TIMING_STROBE_READ) \|
	BF(relax, TIMING_RELAX) \|
	BF(strobe_prog, TIMING_STROBE_PROG);

	clrsetbits_le32(&regs->timing, BM_TIMING_STROBE_READ \| BM_TIMING_RELAX \|
	BM_TIMING_STROBE_PROG, timing);
	}
	#endif

	static void setup_direct_access(struct ocotp_regs *regs, u32 bank, u32 word,
	int write)
	{
	u32 wr_unlock = write ? BV_CTRL_WR_UNLOCK_KEY : 0;
	#ifdef CONFIG_MX7
	u32 addr = bank;
	#elif defined CONFIG_MX8M
	u32 addr = bank << 2 \| word;
	#else
	u32 addr;
	/* Bank 7 and Bank 8 only supports 4 words each for i.MX6ULL */
	if ((is_mx6ull() \|\| is_mx6sll()) && (bank > 7)) {
	bank = bank - 1;
	word += 4;
	}
	addr = bank << 3 \| word;
	#endif

	set_timing(regs);
	clrsetbits_le32(&regs->ctrl, BM_CTRL_WR_UNLOCK \| BM_CTRL_ADDR,
	BF(wr_unlock, CTRL_WR_UNLOCK) \|
	BF(addr, CTRL_ADDR));
	}

	int fuse_sense(u32 bank, u32 word, u32 *val)
	{
	struct ocotp_regs *regs;
	int ret;

	ret = prepare_read(&regs, bank, word, val, __func__);
	if (ret)
	return ret;

	setup_direct_access(regs, bank, word, false);
	writel(BM_READ_CTRL_READ_FUSE, &regs->read_ctrl);
	wait_busy(regs, 1);
	#ifdef CONFIG_MX7
	*val = readl((&regs->read_fuse_data0) + (word << 2));
	#else
	*val = readl(&regs->read_fuse_data);
	#endif

	#ifdef CONFIG_MX7ULP
	if (readl(&regs->out_status) & BM_OUT_STATUS_DED) {
	writel(BM_OUT_STATUS_DED, &regs->out_status_clr);
	printf("mxc_ocotp %s(): fuse read wrong\n", __func__);
	return -EIO;
	}
	#endif

	return finish_access(regs, __func__);
	}

	static int prepare_write(struct ocotp_regs **regs, u32 bank, u32 word,
	const char *caller)
	{
	#ifdef CONFIG_MX7ULP
	u32 val;
	int ret;

	/* Only bank 0 and 1 are redundancy mode, others are ECC mode */
	if (bank != 0 && bank != 1) {
	ret = fuse_sense(bank, word, &val);
	if (ret)
	return ret;

	if (val != 0) {
	printf("mxc_ocotp: The word has been programmed, no more write\n");
	return -EPERM;
	}
	}
	#endif

	return prepare_access(regs, bank, word, true, caller);
	}

	int fuse_prog(u32 bank, u32 word, u32 val)
	{
	struct ocotp_regs *regs;
	int ret;

	ret = prepare_write(&regs, bank, word, __func__);
	if (ret)
	return ret;

	setup_direct_access(regs, bank, word, true);
	#ifdef CONFIG_MX7
	switch (word) {
	case 0:
	writel(0, &regs->data1);
	writel(0, &regs->data2);
	writel(0, &regs->data3);
	writel(val, &regs->data0);
	break;
	case 1:
	writel(val, &regs->data1);
	writel(0, &regs->data2);
	writel(0, &regs->data3);
	writel(0, &regs->data0);
	break;
	case 2:
	writel(0, &regs->data1);
	writel(val, &regs->data2);
	writel(0, &regs->data3);
	writel(0, &regs->data0);
	break;
	case 3:
	writel(0, &regs->data1);
	writel(0, &regs->data2);
	writel(val, &regs->data3);
	writel(0, &regs->data0);
	break;
	}
	wait_busy(regs, BV_TIMING_PROG_US);
	#else
	writel(val, &regs->data);
	wait_busy(regs, BV_TIMING_STROBE_PROG_US);
	#endif
	udelay(WRITE_POSTAMBLE_US);

	#ifdef CONFIG_MX7ULP
	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL \| BM_OUT_STATUS_LOCKED)) {
	writel((BM_OUT_STATUS_PROGFAIL \| BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
	printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
	return -EIO;
	}
	#endif

	return finish_access(regs, __func__);
	}

	int fuse_override(u32 bank, u32 word, u32 val)
	{
	struct ocotp_regs *regs;
	int ret;
	u32 phy_bank;
	u32 phy_word;

	ret = prepare_write(&regs, bank, word, __func__);
	if (ret)
	return ret;

	phy_bank = fuse_bank_physical(bank);
	phy_word = fuse_word_physical(bank, word);

	writel(val, &regs->bank[phy_bank].fuse_regs[phy_word << 2]);

	#ifdef CONFIG_MX7ULP
	if (readl(&regs->out_status) & (BM_OUT_STATUS_PROGFAIL \| BM_OUT_STATUS_LOCKED)) {
	writel((BM_OUT_STATUS_PROGFAIL \| BM_OUT_STATUS_LOCKED), &regs->out_status_clr);
	printf("mxc_ocotp %s(): fuse write is failed\n", __func__);
	return -EIO;
	}
	#endif

	return finish_access(regs, __func__);
	}