Commit 816873ea authored by Cyrille Pitchen's avatar Cyrille Pitchen Committed by Boris Brezillon
Browse files

mtd: spi-nor: parse SFDP 4-byte Address Instruction Table 



Add support for SFDP (JESD216B) 4-byte Address Instruction Table. This
table is optional but when available, we parse it to get the 4-byte
address op codes supported by the memory.
Using these op codes is stateless as opposed to entering the 4-byte
address mode or setting the Base Address Register (BAR).

Flashes that have the 4BAIT table declared can now support
SPINOR_OP_PP_1_1_4_4B and SPINOR_OP_PP_1_4_4_4B opcodes.

Tested on MX25L25673G.

Signed-off-by: default avatarCyrille Pitchen <cyrille.pitchen@microchip.com>
[tudor.ambarus@microchip.com:
- rework erase and page program logic,
- pass DMA-able buffer to spi_nor_read_sfdp(),
- introduce SPI_NOR_HAS_4BAIT
- various minor updates.]
Signed-off-by: default avatarTudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: default avatarBoris Brezillon <boris.brezillon@bootlin.com>
parent d05e21e3

drivers/mtd/spi-nor/spi-nor.c

+192 −1
Original line number Diff line number Diff line
@@ -121,6 +121,7 @@ struct sfdp_parameter_header { 


#define SFDP_BFPT_ID		0xff00	/* Basic Flash Parameter Table */

#define SFDP_SECTOR_MAP_ID	0xff81	/* Sector Map Table */

#define SFDP_4BAIT_ID		0xff84  /* 4-byte Address Instruction Table */



#define SFDP_SIGNATURE		0x50444653U

#define SFDP_JESD216_MAJOR	1
@@ -3239,6 +3240,191 @@ out: 
	return ret;

}



#define SFDP_4BAIT_DWORD_MAX	2



struct sfdp_4bait {

	/* The hardware capability. */

	u32		hwcaps;



	/*

	 * The <supported_bit> bit in DWORD1 of the 4BAIT tells us whether

	 * the associated 4-byte address op code is supported.

	 */

	u32		supported_bit;

};



/**

 * spi_nor_parse_4bait() - parse the 4-Byte Address Instruction Table

 * @nor:		pointer to a 'struct spi_nor'.

 * @param_header:	pointer to the 'struct sfdp_parameter_header' describing

 *			the 4-Byte Address Instruction Table length and version.

 * @params:		pointer to the 'struct spi_nor_flash_parameter' to be.

 *

 * Return: 0 on success, -errno otherwise.

 */

static int spi_nor_parse_4bait(struct spi_nor *nor,

			       const struct sfdp_parameter_header *param_header,

			       struct spi_nor_flash_parameter *params)

{

	static const struct sfdp_4bait reads[] = {

		{ SNOR_HWCAPS_READ,		BIT(0) },

		{ SNOR_HWCAPS_READ_FAST,	BIT(1) },

		{ SNOR_HWCAPS_READ_1_1_2,	BIT(2) },

		{ SNOR_HWCAPS_READ_1_2_2,	BIT(3) },

		{ SNOR_HWCAPS_READ_1_1_4,	BIT(4) },

		{ SNOR_HWCAPS_READ_1_4_4,	BIT(5) },

		{ SNOR_HWCAPS_READ_1_1_1_DTR,	BIT(13) },

		{ SNOR_HWCAPS_READ_1_2_2_DTR,	BIT(14) },

		{ SNOR_HWCAPS_READ_1_4_4_DTR,	BIT(15) },

	};

	static const struct sfdp_4bait programs[] = {

		{ SNOR_HWCAPS_PP,		BIT(6) },

		{ SNOR_HWCAPS_PP_1_1_4,		BIT(7) },

		{ SNOR_HWCAPS_PP_1_4_4,		BIT(8) },

	};

	static const struct sfdp_4bait erases[SNOR_ERASE_TYPE_MAX] = {

		{ 0u /* not used */,		BIT(9) },

		{ 0u /* not used */,		BIT(10) },

		{ 0u /* not used */,		BIT(11) },

		{ 0u /* not used */,		BIT(12) },

	};

	struct spi_nor_pp_command *params_pp = params->page_programs;

	struct spi_nor_erase_map *map = &nor->erase_map;

	struct spi_nor_erase_type *erase_type = map->erase_type;

	u32 *dwords;

	size_t len;

	u32 addr, discard_hwcaps, read_hwcaps, pp_hwcaps, erase_mask;

	int i, ret;



	if (param_header->major != SFDP_JESD216_MAJOR ||

	    param_header->length < SFDP_4BAIT_DWORD_MAX)

		return -EINVAL;



	/* Read the 4-byte Address Instruction Table. */

	len = sizeof(*dwords) * SFDP_4BAIT_DWORD_MAX;



	/* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */

	dwords = kmalloc(len, GFP_KERNEL);

	if (!dwords)

		return -ENOMEM;



	addr = SFDP_PARAM_HEADER_PTP(param_header);

	ret = spi_nor_read_sfdp(nor, addr, len, dwords);

	if (ret)

		return ret;



	/* Fix endianness of the 4BAIT DWORDs. */

	for (i = 0; i < SFDP_4BAIT_DWORD_MAX; i++)

		dwords[i] = le32_to_cpu(dwords[i]);



	/*

	 * Compute the subset of (Fast) Read commands for which the 4-byte

	 * version is supported.

	 */

	discard_hwcaps = 0;

	read_hwcaps = 0;

	for (i = 0; i < ARRAY_SIZE(reads); i++) {

		const struct sfdp_4bait *read = &reads[i];



		discard_hwcaps |= read->hwcaps;

		if ((params->hwcaps.mask & read->hwcaps) &&

		    (dwords[0] & read->supported_bit))

			read_hwcaps |= read->hwcaps;

	}



	/*

	 * Compute the subset of Page Program commands for which the 4-byte

	 * version is supported.

	 */

	pp_hwcaps = 0;

	for (i = 0; i < ARRAY_SIZE(programs); i++) {

		const struct sfdp_4bait *program = &programs[i];



		/*

		 * The 4 Byte Address Instruction (Optional) Table is the only

		 * SFDP table that indicates support for Page Program Commands.

		 * Bypass the params->hwcaps.mask and consider 4BAIT the biggest

		 * authority for specifying Page Program support.

		 */

		discard_hwcaps |= program->hwcaps;

		if (dwords[0] & program->supported_bit)

			pp_hwcaps |= program->hwcaps;

	}



	/*

	 * Compute the subset of Sector Erase commands for which the 4-byte

	 * version is supported.

	 */

	erase_mask = 0;

	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {

		const struct sfdp_4bait *erase = &erases[i];



		if (dwords[0] & erase->supported_bit)

			erase_mask |= BIT(i);

	}



	/* Replicate the sort done for the map's erase types in BFPT. */

	erase_mask = spi_nor_sort_erase_mask(map, erase_mask);



	/*

	 * We need at least one 4-byte op code per read, program and erase

	 * operation; the .read(), .write() and .erase() hooks share the

	 * nor->addr_width value.

	 */

	if (!read_hwcaps || !pp_hwcaps || !erase_mask)

		goto out;



	/*

	 * Discard all operations from the 4-byte instruction set which are

	 * not supported by this memory.

	 */

	params->hwcaps.mask &= ~discard_hwcaps;

	params->hwcaps.mask |= (read_hwcaps | pp_hwcaps);



	/* Use the 4-byte address instruction set. */

	for (i = 0; i < SNOR_CMD_READ_MAX; i++) {

		struct spi_nor_read_command *read_cmd = &params->reads[i];



		read_cmd->opcode = spi_nor_convert_3to4_read(read_cmd->opcode);

	}



	/* 4BAIT is the only SFDP table that indicates page program support. */

	if (pp_hwcaps & SNOR_HWCAPS_PP)

		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP],

					SPINOR_OP_PP_4B, SNOR_PROTO_1_1_1);

	if (pp_hwcaps & SNOR_HWCAPS_PP_1_1_4)

		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_1_4],

					SPINOR_OP_PP_1_1_4_4B,

					SNOR_PROTO_1_1_4);

	if (pp_hwcaps & SNOR_HWCAPS_PP_1_4_4)

		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_4_4],

					SPINOR_OP_PP_1_4_4_4B,

					SNOR_PROTO_1_4_4);



	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {

		if (erase_mask & BIT(i))

			erase_type[i].opcode = (dwords[1] >>

						erase_type[i].idx * 8) & 0xFF;

		else

			spi_nor_set_erase_type(&erase_type[i], 0u, 0xFF);

	}



	/*

	 * We set SNOR_F_HAS_4BAIT in order to skip spi_nor_set_4byte_opcodes()

	 * later because we already did the conversion to 4byte opcodes. Also,

	 * this latest function implements a legacy quirk for the erase size of

	 * Spansion memory. However this quirk is no longer needed with new

	 * SFDP compliant memories.

	 */

	nor->addr_width = 4;

	nor->flags |= SNOR_F_4B_OPCODES | SNOR_F_HAS_4BAIT;



	/* fall through */

out:

	kfree(dwords);

	return ret;

}



/**

 * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.

 * @nor:		pointer to a 'struct spi_nor'
@@ -3336,6 +3522,10 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor, 
			err = spi_nor_parse_smpt(nor, param_header);

			break;



		case SFDP_4BAIT_ID:

			err = spi_nor_parse_4bait(nor, param_header, params);

			break;



		default:

			break;

		}
@@ -3925,7 +4115,8 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, 
	    (JEDEC_MFR(info) == SNOR_MFR_SPANSION && mtd->size > SZ_16M))

		nor->flags |= SNOR_F_4B_OPCODES;



	if (nor->addr_width == 4 && nor->flags & SNOR_F_4B_OPCODES)

	if (nor->addr_width == 4 && nor->flags & SNOR_F_4B_OPCODES &&

	    !(nor->flags & SNOR_F_HAS_4BAIT))

		spi_nor_set_4byte_opcodes(nor);



	if (nor->addr_width > SPI_NOR_MAX_ADDR_WIDTH) {

include/linux/mtd/spi-nor.h

+1 −0
Original line number Diff line number Diff line
@@ -234,6 +234,7 @@ enum spi_nor_option_flags { 
	SNOR_F_USE_CLSR		= BIT(5),

	SNOR_F_BROKEN_RESET	= BIT(6),

	SNOR_F_4B_OPCODES	= BIT(7),

	SNOR_F_HAS_4BAIT	= BIT(8),

};



/**

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