Merge tag 'spi-nor/for-5.19' into mtd/next

SPI NOR core changes:
- Read back written SR value to make sure the write was done correctly.
- Introduce a common function for Read ID that manufacturer drivers can
  use to verify the Octal DTR switch worked correctly.
- Add helpers for read/write any register commands so manufacturer
  drivers don't open code it every time.
- Clarify rdsr dummy cycles documentation.
- Add debugfs entry to expose internal flash parameters and state.

SPI NOR manufacturer drivers changes:
- Add support for Winbond W25Q512NW-IM, and Eon EN25QH256A.
- Move spi_nor_write_ear() to Winbond module since only Winbond flashes
  use it.
- Rework Micron and Cypress Octal DTR enable methods to improve
  readability.
- Use the common Read ID function to verify switch to Octal DTR mode for
  Micron and Cypress flashes.
- Skip polling status on volatile register writes for Micron and Cypress
  flashes since the operation is instant.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

9 files changed, 709 insertions, 308 deletions

diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 6b904e439372..e347b435a038 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -17,6 +17,7 @@ spi-nor-objs			+= sst.o
 spi-nor-objs			+= winbond.o
 spi-nor-objs			+= xilinx.o
 spi-nor-objs			+= xmc.o
+spi-nor-$(CONFIG_DEBUG_FS)	+= debugfs.o
 obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
 
 obj-$(CONFIG_MTD_SPI_NOR)	+= controllers/
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index b4f141ad9c9c..502967c76c5f 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -308,6 +308,52 @@ ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
 }
 
 /**
+ * spi_nor_read_any_reg() - read any register from flash memory, nonvolatile or
+ * volatile.
+ * @nor:        pointer to 'struct spi_nor'.
+ * @op:		SPI memory operation. op->data.buf must be DMA-able.
+ * @proto:	SPI protocol to use for the register operation.
+ *
+ * Return: zero on success, -errno otherwise
+ */
+int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
+			 enum spi_nor_protocol proto)
+{
+	if (!nor->spimem)
+		return -EOPNOTSUPP;
+
+	spi_nor_spimem_setup_op(nor, op, proto);
+	return spi_nor_spimem_exec_op(nor, op);
+}
+
+/**
+ * spi_nor_write_any_volatile_reg() - write any volatile register to flash
+ * memory.
+ * @nor:        pointer to 'struct spi_nor'
+ * @op:		SPI memory operation. op->data.buf must be DMA-able.
+ * @proto:	SPI protocol to use for the register operation.
+ *
+ * Writing volatile registers are instant according to some manufacturers
+ * (Cypress, Micron) and do not need any status polling.
+ *
+ * Return: zero on success, -errno otherwise
+ */
+int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
+				   enum spi_nor_protocol proto)
+{
+	int ret;
+
+	if (!nor->spimem)
+		return -EOPNOTSUPP;
+
+	ret = spi_nor_write_enable(nor);
+	if (ret)
+		return ret;
+	spi_nor_spimem_setup_op(nor, op, proto);
+	return spi_nor_spimem_exec_op(nor, op);
+}
+
+/**
  * spi_nor_write_enable() - Set write enable latch with Write Enable command.
  * @nor:	pointer to 'struct spi_nor'.
  *
@@ -318,11 +364,7 @@ int spi_nor_write_enable(struct spi_nor *nor)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREN, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPI_NOR_WREN_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -349,11 +391,7 @@ int spi_nor_write_disable(struct spi_nor *nor)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRDI, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPI_NOR_WRDI_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -370,6 +408,37 @@ int spi_nor_write_disable(struct spi_nor *nor)
 }
 
 /**
+ * spi_nor_read_id() - Read the JEDEC ID.
+ * @nor:	pointer to 'struct spi_nor'.
+ * @naddr:	number of address bytes to send. Can be zero if the operation
+ *		does not need to send an address.
+ * @ndummy:	number of dummy bytes to send after an opcode or address. Can
+ *		be zero if the operation does not require dummy bytes.
+ * @id:		pointer to a DMA-able buffer where the value of the JEDEC ID
+ *		will be written.
+ * @proto:	the SPI protocol for register operation.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
+		    enum spi_nor_protocol proto)
+{
+	int ret;
+
+	if (nor->spimem) {
+		struct spi_mem_op op =
+			SPI_NOR_READID_OP(naddr, ndummy, id, SPI_NOR_MAX_ID_LEN);
+
+		spi_nor_spimem_setup_op(nor, &op, proto);
+		ret = spi_mem_exec_op(nor->spimem, &op);
+	} else {
+		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
+						    SPI_NOR_MAX_ID_LEN);
+	}
+	return ret;
+}
+
+/**
  * spi_nor_read_sr() - Read the Status Register.
  * @nor:	pointer to 'struct spi_nor'.
  * @sr:		pointer to a DMA-able buffer where the value of the
@@ -382,11 +451,7 @@ int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(1, sr, 0));
+		struct spi_mem_op op = SPI_NOR_RDSR_OP(sr);
 
 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
@@ -426,11 +491,7 @@ int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDCR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(1, cr, 0));
+		struct spi_mem_op op = SPI_NOR_RDCR_OP(cr);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -459,14 +520,7 @@ int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(enable ?
-						  SPINOR_OP_EN4B :
-						  SPINOR_OP_EX4B,
-						  0),
-				  SPI_MEM_OP_NO_ADDR,
-				  SPI_MEM_OP_NO_DUMMY,
-				  SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPI_NOR_EN4B_EX4B_OP(enable);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -500,11 +554,7 @@ static int spansion_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 	nor->bouncebuf[0] = enable << 7;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_BRWR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 0));
+		struct spi_mem_op op = SPI_NOR_BRWR_OP(nor->bouncebuf);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -521,40 +571,6 @@ static int spansion_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 }
 
 /**
- * spi_nor_write_ear() - Write Extended Address Register.
- * @nor:	pointer to 'struct spi_nor'.
- * @ear:	value to write to the Extended Address Register.
- *
- * Return: 0 on success, -errno otherwise.
- */
-int spi_nor_write_ear(struct spi_nor *nor, u8 ear)
-{
-	int ret;
-
-	nor->bouncebuf[0] = ear;
-
-	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREAR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 0));
-
-		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
-
-		ret = spi_mem_exec_op(nor->spimem, &op);
-	} else {
-		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREAR,
-						       nor->bouncebuf, 1);
-	}
-
-	if (ret)
-		dev_dbg(nor->dev, "error %d writing EAR\n", ret);
-
-	return ret;
-}
-
-/**
  * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
  * for new commands.
  * @nor:	pointer to 'struct spi_nor'.
@@ -649,11 +665,7 @@ int spi_nor_global_block_unlock(struct spi_nor *nor)
 		return ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_GBULK, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPI_NOR_GBULK_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -688,11 +700,7 @@ int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
 		return ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(len, sr, 0));
+		struct spi_mem_op op = SPI_NOR_WRSR_OP(sr, len);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -788,6 +796,15 @@ static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
 	if (ret)
 		return ret;
 
+	ret = spi_nor_read_sr(nor, sr_cr);
+	if (ret)
+		return ret;
+
+	if (sr1 != sr_cr[0]) {
+		dev_dbg(nor->dev, "SR: Read back test failed\n");
+		return -EIO;
+	}
+
 	if (nor->flags & SNOR_F_NO_READ_CR)
 		return 0;
 
@@ -892,11 +909,7 @@ static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
 		return ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR2, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(1, sr2, 0));
+		struct spi_mem_op op = SPI_NOR_WRSR2_OP(sr2);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -928,11 +941,7 @@ static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR2, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(1, sr2, 0));
+		struct spi_mem_op op = SPI_NOR_RDSR2_OP(sr2);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -961,11 +970,7 @@ static int spi_nor_erase_chip(struct spi_nor *nor)
 	dev_dbg(nor->dev, " %lldKiB\n", (long long)(nor->mtd.size >> 10));
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CHIP_ERASE, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPI_NOR_CHIP_ERASE_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
 
@@ -1107,10 +1112,8 @@ int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
 
 	if (nor->spimem) {
 		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->erase_opcode, 0),
-				   SPI_MEM_OP_ADDR(nor->addr_width, addr, 0),
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
+						nor->addr_width, addr);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
 
@@ -1629,58 +1632,45 @@ static const struct spi_nor_manufacturer *manufacturers[] = {
 	&spi_nor_xmc,
 };
 
-static const struct flash_info *
-spi_nor_search_part_by_id(const struct flash_info *parts, unsigned int nparts,
-			  const u8 *id)
+static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
+						 const u8 *id)
 {
-	unsigned int i;
+	const struct flash_info *part;
+	unsigned int i, j;
 
-	for (i = 0; i < nparts; i++) {
-		if (parts[i].id_len &&
-		    !memcmp(parts[i].id, id, parts[i].id_len))
-			return &parts[i];
+	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
+		for (j = 0; j < manufacturers[i]->nparts; j++) {
+			part = &manufacturers[i]->parts[j];
+			if (part->id_len &&
+			    !memcmp(part->id, id, part->id_len)) {
+				nor->manufacturer = manufacturers[i];
+				return part;
+			}
+		}
 	}
 
 	return NULL;
 }
 
-static const struct flash_info *spi_nor_read_id(struct spi_nor *nor)
+static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
 {
 	const struct flash_info *info;
 	u8 *id = nor->bouncebuf;
-	unsigned int i;
 	int ret;
 
-	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(SPI_NOR_MAX_ID_LEN, id, 1));
-
-		ret = spi_mem_exec_op(nor->spimem, &op);
-	} else {
-		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
-						    SPI_NOR_MAX_ID_LEN);
-	}
+	ret = spi_nor_read_id(nor, 0, 0, id, nor->reg_proto);
 	if (ret) {
 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
 		return ERR_PTR(ret);
 	}
 
-	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
-		info = spi_nor_search_part_by_id(manufacturers[i]->parts,
-						 manufacturers[i]->nparts,
-						 id);
-		if (info) {
-			nor->manufacturer = manufacturers[i];
-			return info;
-		}
+	info = spi_nor_match_id(nor, id);
+	if (!info) {
+		dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
+			SPI_NOR_MAX_ID_LEN, id);
+		return ERR_PTR(-ENODEV);
 	}
-
-	dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
-		SPI_NOR_MAX_ID_LEN, id);
-	return ERR_PTR(-ENODEV);
+	return info;
 }
 
 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
@@ -1860,7 +1850,7 @@ int spi_nor_hwcaps_read2cmd(u32 hwcaps)
 				  ARRAY_SIZE(hwcaps_read2cmd));
 }
 
-static int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
+int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
 {
 	static const int hwcaps_pp2cmd[][2] = {
 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
@@ -1919,10 +1909,7 @@ static int spi_nor_spimem_check_op(struct spi_nor *nor,
 static int spi_nor_spimem_check_readop(struct spi_nor *nor,
 				       const struct spi_nor_read_command *read)
 {
-	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(read->opcode, 0),
-					  SPI_MEM_OP_ADDR(3, 0, 0),
-					  SPI_MEM_OP_DUMMY(1, 0),
-					  SPI_MEM_OP_DATA_IN(2, NULL, 0));
+	struct spi_mem_op op = SPI_NOR_READ_OP(read->opcode);
 
 	spi_nor_spimem_setup_op(nor, &op, read->proto);
 
@@ -1945,10 +1932,7 @@ static int spi_nor_spimem_check_readop(struct spi_nor *nor,
 static int spi_nor_spimem_check_pp(struct spi_nor *nor,
 				   const struct spi_nor_pp_command *pp)
 {
-	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(pp->opcode, 0),
-					  SPI_MEM_OP_ADDR(3, 0, 0),
-					  SPI_MEM_OP_NO_DUMMY,
-					  SPI_MEM_OP_DATA_OUT(2, NULL, 0));
+	struct spi_mem_op op = SPI_NOR_PP_OP(pp->opcode);
 
 	spi_nor_spimem_setup_op(nor, &op, pp->proto);
 
@@ -2772,10 +2756,7 @@ static void spi_nor_soft_reset(struct spi_nor *nor)
 	struct spi_mem_op op;
 	int ret;
 
-	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRSTEN, 0),
-			SPI_MEM_OP_NO_DUMMY,
-			SPI_MEM_OP_NO_ADDR,
-			SPI_MEM_OP_NO_DATA);
+	op = (struct spi_mem_op)SPINOR_SRSTEN_OP;
 
 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -2785,10 +2766,7 @@ static void spi_nor_soft_reset(struct spi_nor *nor)
 		return;
 	}
 
-	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRST, 0),
-			SPI_MEM_OP_NO_DUMMY,
-			SPI_MEM_OP_NO_ADDR,
-			SPI_MEM_OP_NO_DATA);
+	op = (struct spi_mem_op)SPINOR_SRST_OP;
 
 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
@@ -2876,8 +2854,8 @@ void spi_nor_restore(struct spi_nor *nor)
 }
 EXPORT_SYMBOL_GPL(spi_nor_restore);
 
-static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
-						 const char *name)
+static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
+						   const char *name)
 {
 	unsigned int i, j;
 
@@ -2899,12 +2877,10 @@ static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
 	const struct flash_info *info = NULL;
 
 	if (name)
-		info = spi_nor_match_id(nor, name);
+		info = spi_nor_match_name(nor, name);
 	/* Try to auto-detect if chip name wasn't specified or not found */
 	if (!info)
-		info = spi_nor_read_id(nor);
-	if (IS_ERR_OR_NULL(info))
-		return ERR_PTR(-ENOENT);
+		return spi_nor_detect(nor);
 
 	/*
 	 * If caller has specified name of flash model that can normally be
@@ -2913,7 +2889,7 @@ static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
 	if (name && info->id_len) {
 		const struct flash_info *jinfo;
 
-		jinfo = spi_nor_read_id(nor);
+		jinfo = spi_nor_detect(nor);
 		if (IS_ERR(jinfo)) {
 			return jinfo;
 		} else if (jinfo != info) {
@@ -3156,6 +3132,8 @@ static int spi_nor_probe(struct spi_mem *spimem)
 	if (ret)
 		return ret;
 
+	spi_nor_debugfs_register(nor);
+
 	/*
 	 * None of the existing parts have > 512B pages, but let's play safe
 	 * and add this logic so that if anyone ever adds support for such
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index b7fd760e3b47..3f841ec36e56 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -11,6 +11,110 @@
 
 #define SPI_NOR_MAX_ID_LEN	6
 
+/* Standard SPI NOR flash operations. */
+#define SPI_NOR_READID_OP(naddr, ndummy, buf, len)			\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 0),			\
+		   SPI_MEM_OP_ADDR(naddr, 0, 0),			\
+		   SPI_MEM_OP_DUMMY(ndummy, 0),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 0))
+
+#define SPI_NOR_WREN_OP							\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREN, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_WRDI_OP							\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRDI, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_RDSR_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, buf, 0))
+
+#define SPI_NOR_WRSR_OP(buf, len)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(len, buf, 0))
+
+#define SPI_NOR_RDSR2_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR2, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
+
+#define SPI_NOR_WRSR2_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR2, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
+
+#define SPI_NOR_RDCR_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDCR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, buf, 0))
+
+#define SPI_NOR_EN4B_EX4B_OP(enable)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(enable ? SPINOR_OP_EN4B : SPINOR_OP_EX4B, 0),	\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_BRWR_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_BRWR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
+
+#define SPI_NOR_GBULK_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_GBULK, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_CHIP_ERASE_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CHIP_ERASE, 0),		\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_SECTOR_ERASE_OP(opcode, addr_width, addr)		\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 0),				\
+		   SPI_MEM_OP_ADDR(addr_width, addr, 0),		\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPI_NOR_READ_OP(opcode)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 0),				\
+		   SPI_MEM_OP_ADDR(3, 0, 0),				\
+		   SPI_MEM_OP_DUMMY(1, 0),				\
+		   SPI_MEM_OP_DATA_IN(2, NULL, 0))
+
+#define SPI_NOR_PP_OP(opcode)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 0),				\
+		   SPI_MEM_OP_ADDR(3, 0, 0),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(2, NULL, 0))
+
+#define SPINOR_SRSTEN_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRSTEN, 0),			\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINOR_SRST_OP							\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRST, 0),			\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DATA)
+
+/* Keep these in sync with the list in debugfs.c */
 enum spi_nor_option_flags {
 	SNOR_F_HAS_SR_TB	= BIT(0),
 	SNOR_F_NO_OP_CHIP_ERASE	= BIT(1),
@@ -236,9 +340,10 @@ struct spi_nor_otp {
  * @writesize		Minimal writable flash unit size. Defaults to 1. Set to
  *			ECC unit size for ECC-ed flashes.
  * @page_size:		the page size of the SPI NOR flash memory.
- * @rdsr_dummy:		dummy cycles needed for Read Status Register command.
+ * @rdsr_dummy:		dummy cycles needed for Read Status Register command
+ *			in octal DTR mode.
  * @rdsr_addr_nbytes:	dummy address bytes needed for Read Status Register
- *			command.
+ *			command in octal DTR mode.
  * @hwcaps:		describes the read and page program hardware
  *			capabilities.
  * @reads:		read capabilities ordered by priority: the higher index
@@ -526,7 +631,6 @@ void spi_nor_spimem_setup_op(const struct spi_nor *nor,
 int spi_nor_write_enable(struct spi_nor *nor);
 int spi_nor_write_disable(struct spi_nor *nor);
 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable);
-int spi_nor_write_ear(struct spi_nor *nor, u8 ear);
 int spi_nor_wait_till_ready(struct spi_nor *nor);
 int spi_nor_global_block_unlock(struct spi_nor *nor);
 int spi_nor_lock_and_prep(struct spi_nor *nor);
@@ -534,6 +638,8 @@ void spi_nor_unlock_and_unprep(struct spi_nor *nor);
 int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor);
 int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor);
 int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor);
+int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
+		    enum spi_nor_protocol reg_proto);
 int spi_nor_read_sr(struct spi_nor *nor, u8 *sr);
 int spi_nor_sr_ready(struct spi_nor *nor);
 int spi_nor_read_cr(struct spi_nor *nor, u8 *cr);
@@ -545,6 +651,10 @@ ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len,
 			  u8 *buf);
 ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
 			   const u8 *buf);
+int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
+			 enum spi_nor_protocol proto);
+int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
+				   enum spi_nor_protocol proto);
 int spi_nor_erase_sector(struct spi_nor *nor, u32 addr);
 
 int spi_nor_otp_read_secr(struct spi_nor *nor, loff_t addr, size_t len, u8 *buf);
@@ -555,6 +665,7 @@ int spi_nor_otp_lock_sr2(struct spi_nor *nor, unsigned int region);
 int spi_nor_otp_is_locked_sr2(struct spi_nor *nor, unsigned int region);
 
 int spi_nor_hwcaps_read2cmd(u32 hwcaps);
+int spi_nor_hwcaps_pp2cmd(u32 hwcaps);
 u8 spi_nor_convert_3to4_read(u8 opcode);
 void spi_nor_set_read_settings(struct spi_nor_read_command *read,
 			       u8 num_mode_clocks,
@@ -590,4 +701,10 @@ static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
 	return container_of(mtd, struct spi_nor, mtd);
 }
 
+#ifdef CONFIG_DEBUG_FS
+void spi_nor_debugfs_register(struct spi_nor *nor);
+#else
+static inline void spi_nor_debugfs_register(struct spi_nor *nor) {}
+#endif
+
 #endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */
diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c
new file mode 100644
index 000000000000..eaf84f7a0676
--- /dev/null
+++ b/drivers/mtd/spi-nor/debugfs.c
@@ -0,0 +1,249 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/mtd/spi-nor.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+#include <linux/debugfs.h>
+
+#include "core.h"
+
+#define SPI_NOR_DEBUGFS_ROOT "spi-nor"
+
+#define SNOR_F_NAME(name) [ilog2(SNOR_F_##name)] = #name
+static const char *const snor_f_names[] = {
+	SNOR_F_NAME(HAS_SR_TB),
+	SNOR_F_NAME(NO_OP_CHIP_ERASE),
+	SNOR_F_NAME(BROKEN_RESET),
+	SNOR_F_NAME(4B_OPCODES),
+	SNOR_F_NAME(HAS_4BAIT),
+	SNOR_F_NAME(HAS_LOCK),
+	SNOR_F_NAME(HAS_16BIT_SR),
+	SNOR_F_NAME(NO_READ_CR),
+	SNOR_F_NAME(HAS_SR_TB_BIT6),
+	SNOR_F_NAME(HAS_4BIT_BP),
+	SNOR_F_NAME(HAS_SR_BP3_BIT6),
+	SNOR_F_NAME(IO_MODE_EN_VOLATILE),
+	SNOR_F_NAME(SOFT_RESET),
+	SNOR_F_NAME(SWP_IS_VOLATILE),
+};
+#undef SNOR_F_NAME
+
+static const char *spi_nor_protocol_name(enum spi_nor_protocol proto)
+{
+	switch (proto) {
+	case SNOR_PROTO_1_1_1:     return "1S-1S-1S";
+	case SNOR_PROTO_1_1_2:     return "1S-1S-2S";
+	case SNOR_PROTO_1_1_4:     return "1S-1S-4S";
+	case SNOR_PROTO_1_1_8:     return "1S-1S-8S";
+	case SNOR_PROTO_1_2_2:     return "1S-2S-2S";
+	case SNOR_PROTO_1_4_4:     return "1S-4S-4S";
+	case SNOR_PROTO_1_8_8:     return "1S-8S-8S";
+	case SNOR_PROTO_2_2_2:     return "2S-2S-2S";
+	case SNOR_PROTO_4_4_4:     return "4S-4S-4S";
+	case SNOR_PROTO_8_8_8:     return "8S-8S-8S";
+	case SNOR_PROTO_1_1_1_DTR: return "1D-1D-1D";
+	case SNOR_PROTO_1_2_2_DTR: return "1D-2D-2D";
+	case SNOR_PROTO_1_4_4_DTR: return "1D-4D-4D";
+	case SNOR_PROTO_1_8_8_DTR: return "1D-8D-8D";
+	case SNOR_PROTO_8_8_8_DTR: return "8D-8D-8D";
+	}
+
+	return "<unknown>";
+}
+
+static void spi_nor_print_flags(struct seq_file *s, unsigned long flags,
+				const char *const *names, int names_len)
+{
+	bool sep = false;
+	int i;
+
+	for (i = 0; i < sizeof(flags) * BITS_PER_BYTE; i++) {
+		if (!(flags & BIT(i)))
+			continue;
+		if (sep)
+			seq_puts(s, " | ");
+		sep = true;
+		if (i < names_len && names[i])
+			seq_puts(s, names[i]);
+		else
+			seq_printf(s, "1<<%d", i);
+	}
+}
+
+static int spi_nor_params_show(struct seq_file *s, void *data)
+{
+	struct spi_nor *nor = s->private;
+	struct spi_nor_flash_parameter *params = nor->params;
+	struct spi_nor_erase_map *erase_map = &params->erase_map;
+	struct spi_nor_erase_region *region;
+	const struct flash_info *info = nor->info;
+	char buf[16], *str;
+	int i;
+
+	seq_printf(s, "name\t\t%s\n", info->name);
+	seq_printf(s, "id\t\t%*ph\n", info->id_len, info->id);
+	string_get_size(params->size, 1, STRING_UNITS_2, buf, sizeof(buf));
+	seq_printf(s, "size\t\t%s\n", buf);
+	seq_printf(s, "write size\t%u\n", params->writesize);
+	seq_printf(s, "page size\t%u\n", params->page_size);
+	seq_printf(s, "address width\t%u\n", nor->addr_width);
+
+	seq_puts(s, "flags\t\t");
+	spi_nor_print_flags(s, nor->flags, snor_f_names, sizeof(snor_f_names));
+	seq_puts(s, "\n");
+
+	seq_puts(s, "\nopcodes\n");
+	seq_printf(s, " read\t\t0x%02x\n", nor->read_opcode);
+	seq_printf(s, "  dummy cycles\t%u\n", nor->read_dummy);
+	seq_printf(s, " erase\t\t0x%02x\n", nor->erase_opcode);
+	seq_printf(s, " program\t0x%02x\n", nor->program_opcode);
+
+	switch (nor->cmd_ext_type) {
+	case SPI_NOR_EXT_NONE:
+		str = "none";
+		break;
+	case SPI_NOR_EXT_REPEAT:
+		str = "repeat";
+		break;
+	case SPI_NOR_EXT_INVERT:
+		str = "invert";
+		break;
+	default:
+		str = "<unknown>";
+		break;
+	}
+	seq_printf(s, " 8D extension\t%s\n", str);
+
+	seq_puts(s, "\nprotocols\n");
+	seq_printf(s, " read\t\t%s\n",
+		   spi_nor_protocol_name(nor->read_proto));
+	seq_printf(s, " write\t\t%s\n",
+		   spi_nor_protocol_name(nor->write_proto));
+	seq_printf(s, " register\t%s\n",
+		   spi_nor_protocol_name(nor->reg_proto));
+
+	seq_puts(s, "\nerase commands\n");
+	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
+		struct spi_nor_erase_type *et = &erase_map->erase_type[i];
+
+		if (et->size) {
+			string_get_size(et->size, 1, STRING_UNITS_2, buf,
+					sizeof(buf));
+			seq_printf(s, " %02x (%s) [%d]\n", et->opcode, buf, i);
+		}
+	}
+
+	if (!(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
+		string_get_size(params->size, 1, STRING_UNITS_2, buf, sizeof(buf));
+		seq_printf(s, " %02x (%s)\n", SPINOR_OP_CHIP_ERASE, buf);
+	}
+
+	seq_puts(s, "\nsector map\n");
+	seq_puts(s, " region (in hex)   | erase mask | flags\n");
+	seq_puts(s, " ------------------+------------+----------\n");
+	for (region = erase_map->regions;
+	     region;
+	     region = spi_nor_region_next(region)) {
+		u64 start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
+		u64 flags = region->offset & SNOR_ERASE_FLAGS_MASK;
+		u64 end = start + region->size - 1;
+
+		seq_printf(s, " %08llx-%08llx |     [%c%c%c%c] | %s\n",
+			   start, end,
+			   flags & BIT(0) ? '0' : ' ',
+			   flags & BIT(1) ? '1' : ' ',
+			   flags & BIT(2) ? '2' : ' ',
+			   flags & BIT(3) ? '3' : ' ',
+			   flags & SNOR_OVERLAID_REGION ? "overlaid" : "");
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(spi_nor_params);
+
+static void spi_nor_print_read_cmd(struct seq_file *s, u32 cap,
+				   struct spi_nor_read_command *cmd)
+{
+	seq_printf(s, " %s%s\n", spi_nor_protocol_name(cmd->proto),
+		   cap == SNOR_HWCAPS_READ_FAST ? " (fast read)" : "");
+	seq_printf(s, "  opcode\t0x%02x\n", cmd->opcode);
+	seq_printf(s, "  mode cycles\t%u\n", cmd->num_mode_clocks);
+	seq_printf(s, "  dummy cycles\t%u\n", cmd->num_wait_states);
+}
+
+static void spi_nor_print_pp_cmd(struct seq_file *s,
+				 struct spi_nor_pp_command *cmd)
+{
+	seq_printf(s, " %s\n", spi_nor_protocol_name(cmd->proto));
+	seq_printf(s, "  opcode\t0x%02x\n", cmd->opcode);
+}
+
+static int spi_nor_capabilities_show(struct seq_file *s, void *data)
+{
+	struct spi_nor *nor = s->private;
+	struct spi_nor_flash_parameter *params = nor->params;
+	u32 hwcaps = params->hwcaps.mask;
+	int i, cmd;
+
+	seq_puts(s, "Supported read modes by the flash\n");
+	for (i = 0; i < sizeof(hwcaps) * BITS_PER_BYTE; i++) {
+		if (!(hwcaps & BIT(i)))
+			continue;
+
+		cmd = spi_nor_hwcaps_read2cmd(BIT(i));
+		if (cmd < 0)
+			continue;
+
+		spi_nor_print_read_cmd(s, BIT(i), &params->reads[cmd]);
+		hwcaps &= ~BIT(i);
+	}
+
+	seq_puts(s, "\nSupported page program modes by the flash\n");
+	for (i = 0; i < sizeof(hwcaps) * BITS_PER_BYTE; i++) {
+		if (!(hwcaps & BIT(i)))
+			continue;
+
+		cmd = spi_nor_hwcaps_pp2cmd(BIT(i));
+		if (cmd < 0)
+			continue;
+
+		spi_nor_print_pp_cmd(s, &params->page_programs[cmd]);
+		hwcaps &= ~BIT(i);
+	}
+
+	if (hwcaps)
+		seq_printf(s, "\nunknown hwcaps 0x%x\n", hwcaps);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(spi_nor_capabilities);
+
+static void spi_nor_debugfs_unregister(void *data)
+{
+	struct spi_nor *nor = data;
+
+	debugfs_remove(nor->debugfs_root);
+	nor->debugfs_root = NULL;
+}
+
+void spi_nor_debugfs_register(struct spi_nor *nor)
+{
+	struct dentry *rootdir, *d;
+	int ret;
+
+	/* Create rootdir once. Will never be deleted again. */
+	rootdir = debugfs_lookup(SPI_NOR_DEBUGFS_ROOT, NULL);
+	if (!rootdir)
+		rootdir = debugfs_create_dir(SPI_NOR_DEBUGFS_ROOT, NULL);
+
+	ret = devm_add_action(nor->dev, spi_nor_debugfs_unregister, nor);
+	if (ret)
+		return;
+
+	d = debugfs_create_dir(dev_name(nor->dev), rootdir);
+	nor->debugfs_root = d;
+
+	debugfs_create_file("params", 0444, d, nor, &spi_nor_params_fops);
+	debugfs_create_file("capabilities", 0444, d, nor,
+			    &spi_nor_capabilities_fops);
+}
diff --git a/drivers/mtd/spi-nor/eon.c b/drivers/mtd/spi-nor/eon.c
index 8c1c57530281..50a11053711f 100644
--- a/drivers/mtd/spi-nor/eon.c
+++ b/drivers/mtd/spi-nor/eon.c
@@ -25,7 +25,8 @@ static const struct flash_info eon_nor_parts[] = {
 	{ "en25qh64",   INFO(0x1c7017, 0, 64 * 1024,  128)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ) },
 	{ "en25qh128",  INFO(0x1c7018, 0, 64 * 1024,  256) },
-	{ "en25qh256",  INFO(0x1c7019, 0, 64 * 1024,  512) },
+	{ "en25qh256",  INFO(0x1c7019, 0, 64 * 1024,  512)
+		PARSE_SFDP },
 	{ "en25s64",	INFO(0x1c3817, 0, 64 * 1024,  128)
 		NO_SFDP_FLAGS(SECT_4K) },
 };
diff --git a/drivers/mtd/spi-nor/micron-st.c b/drivers/mtd/spi-nor/micron-st.c
index 8a20475ce77a..a96f74e0f568 100644
--- a/drivers/mtd/spi-nor/micron-st.c
+++ b/drivers/mtd/spi-nor/micron-st.c
@@ -28,82 +28,87 @@
 #define FSR_P_ERR		BIT(4)	/* Program operation status */
 #define FSR_PT_ERR		BIT(1)	/* Protection error bit */
 
-static int micron_st_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
+/* Micron ST SPI NOR flash operations. */
+#define MICRON_ST_NOR_WR_ANY_REG_OP(naddr, addr, ndata, buf)		\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_MT_WR_ANY_REG, 0),		\
+		   SPI_MEM_OP_ADDR(naddr, addr, 0),			\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(ndata, buf, 0))
+
+#define MICRON_ST_RDFSR_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDFSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, buf, 0))
+
+#define MICRON_ST_CLFSR_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLFSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+static int micron_st_nor_octal_dtr_en(struct spi_nor *nor)
 {
 	struct spi_mem_op op;
 	u8 *buf = nor->bouncebuf;
 	int ret;
 
-	if (enable) {
-		/* Use 20 dummy cycles for memory array reads. */
-		ret = spi_nor_write_enable(nor);
-		if (ret)
-			return ret;
-
-		*buf = 20;
-		op = (struct spi_mem_op)
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_MT_WR_ANY_REG, 1),
-				   SPI_MEM_OP_ADDR(3, SPINOR_REG_MT_CFR1V, 1),
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(1, buf, 1));
-
-		ret = spi_mem_exec_op(nor->spimem, &op);
-		if (ret)
-			return ret;
-
-		ret = spi_nor_wait_till_ready(nor);
-		if (ret)
-			return ret;
-	}
+	/* Use 20 dummy cycles for memory array reads. */
+	*buf = 20;
+	op = (struct spi_mem_op)
+		MICRON_ST_NOR_WR_ANY_REG_OP(3, SPINOR_REG_MT_CFR1V, 1, buf);
+	ret = spi_nor_write_any_volatile_reg(nor, &op, nor->reg_proto);
+	if (ret)
+		return ret;
 
-	ret = spi_nor_write_enable(nor);
+	buf[0] = SPINOR_MT_OCT_DTR;
+	op = (struct spi_mem_op)
+		MICRON_ST_NOR_WR_ANY_REG_OP(3, SPINOR_REG_MT_CFR0V, 1, buf);
+	ret = spi_nor_write_any_volatile_reg(nor, &op, nor->reg_proto);
 	if (ret)
 		return ret;
 
-	if (enable) {
-		buf[0] = SPINOR_MT_OCT_DTR;
-	} else {
-		/*
-		 * The register is 1-byte wide, but 1-byte transactions are not
-		 * allowed in 8D-8D-8D mode. The next register is the dummy
-		 * cycle configuration register. Since the transaction needs to
-		 * be at least 2 bytes wide, set the next register to its
-		 * default value. This also makes sense because the value was
-		 * changed when enabling 8D-8D-8D mode, it should be reset when
-		 * disabling.
-		 */
-		buf[0] = SPINOR_MT_EXSPI;
-		buf[1] = SPINOR_REG_MT_CFR1V_DEF;
+	/* Read flash ID to make sure the switch was successful. */
+	ret = spi_nor_read_id(nor, 0, 8, buf, SNOR_PROTO_8_8_8_DTR);
+	if (ret) {
+		dev_dbg(nor->dev, "error %d reading JEDEC ID after enabling 8D-8D-8D mode\n", ret);
+		return ret;
 	}
 
-	op = (struct spi_mem_op)
-		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_MT_WR_ANY_REG, 1),
-			   SPI_MEM_OP_ADDR(enable ? 3 : 4,
-					   SPINOR_REG_MT_CFR0V, 1),
-			   SPI_MEM_OP_NO_DUMMY,
-			   SPI_MEM_OP_DATA_OUT(enable ? 1 : 2, buf, 1));
+	if (memcmp(buf, nor->info->id, nor->info->id_len))
+		return -EINVAL;
 
-	if (!enable)
-		spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);
+	return 0;
+}
 
-	ret = spi_mem_exec_op(nor->spimem, &op);
+static int micron_st_nor_octal_dtr_dis(struct spi_nor *nor)
+{
+	struct spi_mem_op op;
+	u8 *buf = nor->bouncebuf;
+	int ret;
+
+	/*
+	 * The register is 1-byte wide, but 1-byte transactions are not allowed
+	 * in 8D-8D-8D mode. The next register is the dummy cycle configuration
+	 * register. Since the transaction needs to be at least 2 bytes wide,
+	 * set the next register to its default value. This also makes sense
+	 * because the value was changed when enabling 8D-8D-8D mode, it should
+	 * be reset when disabling.
+	 */
+	buf[0] = SPINOR_MT_EXSPI;
+	buf[1] = SPINOR_REG_MT_CFR1V_DEF;
+	op = (struct spi_mem_op)
+		MICRON_ST_NOR_WR_ANY_REG_OP(4, SPINOR_REG_MT_CFR0V, 2, buf);
+	ret = spi_nor_write_any_volatile_reg(nor, &op, SNOR_PROTO_8_8_8_DTR);
 	if (ret)
 		return ret;
 
 	/* Read flash ID to make sure the switch was successful. */
-	op = (struct spi_mem_op)
-		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),
-			   SPI_MEM_OP_NO_ADDR,
-			   SPI_MEM_OP_DUMMY(enable ? 8 : 0, 1),
-			   SPI_MEM_OP_DATA_IN(round_up(nor->info->id_len, 2),
-					      buf, 1));
-
-	if (enable)
-		spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);
-
-	ret = spi_mem_exec_op(nor->spimem, &op);
-	if (ret)
+	ret = spi_nor_read_id(nor, 0, 0, buf, SNOR_PROTO_1_1_1);
+	if (ret) {
+		dev_dbg(nor->dev, "error %d reading JEDEC ID after disabling 8D-8D-8D mode\n", ret);
 		return ret;
+	}
 
 	if (memcmp(buf, nor->info->id, nor->info->id_len))
 		return -EINVAL;
@@ -111,6 +116,12 @@ static int micron_st_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
 	return 0;
 }
 
+static int micron_st_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
+{
+	return enable ? micron_st_nor_octal_dtr_en(nor) :
+			micron_st_nor_octal_dtr_dis(nor);
+}
+
 static void mt35xu512aba_default_init(struct spi_nor *nor)
 {
 	nor->params->octal_dtr_enable = micron_st_nor_octal_dtr_enable;
@@ -322,11 +333,7 @@ static int micron_st_nor_read_fsr(struct spi_nor *nor, u8 *fsr)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDFSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(1, fsr, 0));
+		struct spi_mem_op op = MICRON_ST_RDFSR_OP(fsr);
 
 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
@@ -361,11 +368,7 @@ static void micron_st_nor_clear_fsr(struct spi_nor *nor)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLFSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = MICRON_ST_CLFSR_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
diff --git a/drivers/mtd/spi-nor/spansion.c b/drivers/mtd/spi-nor/spansion.c
index f24e546e04a5..43cd6cd92537 100644
--- a/drivers/mtd/spi-nor/spansion.c
+++ b/drivers/mtd/spi-nor/spansion.c
@@ -23,94 +23,89 @@
 #define SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS	0
 #define SPINOR_OP_CYPRESS_RD_FAST		0xee
 
-/**
- * cypress_nor_octal_dtr_enable() - Enable octal DTR on Cypress flashes.
- * @nor:		pointer to a 'struct spi_nor'
- * @enable:              whether to enable or disable Octal DTR
- *
- * This also sets the memory access latency cycles to 24 to allow the flash to
- * run at up to 200MHz.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int cypress_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
+/* Cypress SPI NOR flash operations. */
+#define CYPRESS_NOR_WR_ANY_REG_OP(naddr, addr, ndata, buf)		\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 0),		\
+		   SPI_MEM_OP_ADDR(naddr, addr, 0),			\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(ndata, buf, 0))
+
+#define CYPRESS_NOR_RD_ANY_REG_OP(naddr, addr, buf)			\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RD_ANY_REG, 0),		\
+		   SPI_MEM_OP_ADDR(naddr, addr, 0),			\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, buf, 0))
+
+#define SPANSION_CLSR_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+static int cypress_nor_octal_dtr_en(struct spi_nor *nor)
 {
 	struct spi_mem_op op;
 	u8 *buf = nor->bouncebuf;
 	int ret;
 
-	if (enable) {
-		/* Use 24 dummy cycles for memory array reads. */
-		ret = spi_nor_write_enable(nor);
-		if (ret)
-			return ret;
-
-		*buf = SPINOR_REG_CYPRESS_CFR2V_MEMLAT_11_24;
-		op = (struct spi_mem_op)
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
-				   SPI_MEM_OP_ADDR(3, SPINOR_REG_CYPRESS_CFR2V,
-						   1),
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_OUT(1, buf, 1));
+	/* Use 24 dummy cycles for memory array reads. */
+	*buf = SPINOR_REG_CYPRESS_CFR2V_MEMLAT_11_24;
+	op = (struct spi_mem_op)
+		CYPRESS_NOR_WR_ANY_REG_OP(3, SPINOR_REG_CYPRESS_CFR2V, 1, buf);
 
-		ret = spi_mem_exec_op(nor->spimem, &op);
-		if (ret)
-			return ret;
+	ret = spi_nor_write_any_volatile_reg(nor, &op, nor->reg_proto);
+	if (ret)
+		return ret;
 
-		ret = spi_nor_wait_till_ready(nor);
-		if (ret)
-			return ret;
+	nor->read_dummy = 24;
 
-		nor->read_dummy = 24;
-	}
+	/* Set the octal and DTR enable bits. */
+	buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_EN;
+	op = (struct spi_mem_op)
+		CYPRESS_NOR_WR_ANY_REG_OP(3, SPINOR_REG_CYPRESS_CFR5V, 1, buf);
 
-	/* Set/unset the octal and DTR enable bits. */
-	ret = spi_nor_write_enable(nor);
+	ret = spi_nor_write_any_volatile_reg(nor, &op, nor->reg_proto);
 	if (ret)
 		return ret;
 
-	if (enable) {
-		buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_EN;
-	} else {
-		/*
-		 * The register is 1-byte wide, but 1-byte transactions are not
-		 * allowed in 8D-8D-8D mode. Since there is no register at the
-		 * next location, just initialize the value to 0 and let the
-		 * transaction go on.
-		 */
-		buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS;
-		buf[1] = 0;
+	/* Read flash ID to make sure the switch was successful. */
+	ret = spi_nor_read_id(nor, 4, 3, buf, SNOR_PROTO_8_8_8_DTR);
+	if (ret) {
+		dev_dbg(nor->dev, "error %d reading JEDEC ID after enabling 8D-8D-8D mode\n", ret);
+		return ret;
 	}
 
-	op = (struct spi_mem_op)
-		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
-			   SPI_MEM_OP_ADDR(enable ? 3 : 4,
-					   SPINOR_REG_CYPRESS_CFR5V,
-					   1),
-			   SPI_MEM_OP_NO_DUMMY,
-			   SPI_MEM_OP_DATA_OUT(enable ? 1 : 2, buf, 1));
+	if (memcmp(buf, nor->info->id, nor->info->id_len))
+		return -EINVAL;
 
-	if (!enable)
-		spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);
+	return 0;
+}
 
-	ret = spi_mem_exec_op(nor->spimem, &op);
+static int cypress_nor_octal_dtr_dis(struct spi_nor *nor)
+{
+	struct spi_mem_op op;
+	u8 *buf = nor->bouncebuf;
+	int ret;
+
+	/*
+	 * The register is 1-byte wide, but 1-byte transactions are not allowed
+	 * in 8D-8D-8D mode. Since there is no register at the next location,
+	 * just initialize the value to 0 and let the transaction go on.
+	 */
+	buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS;
+	buf[1] = 0;
+	op = (struct spi_mem_op)
+		CYPRESS_NOR_WR_ANY_REG_OP(4, SPINOR_REG_CYPRESS_CFR5V, 2, buf);
+	ret = spi_nor_write_any_volatile_reg(nor, &op, SNOR_PROTO_8_8_8_DTR);
 	if (ret)
 		return ret;
 
 	/* Read flash ID to make sure the switch was successful. */
-	op = (struct spi_mem_op)
-		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),
-			   SPI_MEM_OP_ADDR(enable ? 4 : 0, 0, 1),
-			   SPI_MEM_OP_DUMMY(enable ? 3 : 0, 1),
-			   SPI_MEM_OP_DATA_IN(round_up(nor->info->id_len, 2),
-					      buf, 1));
-
-	if (enable)
-		spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);
-
-	ret = spi_mem_exec_op(nor->spimem, &op);
-	if (ret)
+	ret = spi_nor_read_id(nor, 0, 0, buf, SNOR_PROTO_1_1_1);
+	if (ret) {
+		dev_dbg(nor->dev, "error %d reading JEDEC ID after disabling 8D-8D-8D mode\n", ret);
 		return ret;
+	}
 
 	if (memcmp(buf, nor->info->id, nor->info->id_len))
 		return -EINVAL;
@@ -118,6 +113,22 @@ static int cypress_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
 	return 0;
 }
 
+/**
+ * cypress_nor_octal_dtr_enable() - Enable octal DTR on Cypress flashes.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @enable:              whether to enable or disable Octal DTR
+ *
+ * This also sets the memory access latency cycles to 24 to allow the flash to
+ * run at up to 200MHz.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int cypress_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
+{
+	return enable ? cypress_nor_octal_dtr_en(nor) :
+			cypress_nor_octal_dtr_dis(nor);
+}
+
 static void s28hs512t_default_init(struct spi_nor *nor)
 {
 	nor->params->octal_dtr_enable = cypress_nor_octal_dtr_enable;
@@ -162,12 +173,12 @@ static int s28hs512t_post_bfpt_fixup(struct spi_nor *nor,
 	 * CFR3V[4] and set the correct size.
 	 */
 	struct spi_mem_op op =
-		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RD_ANY_REG, 1),
-			   SPI_MEM_OP_ADDR(3, SPINOR_REG_CYPRESS_CFR3V, 1),
-			   SPI_MEM_OP_NO_DUMMY,
-			   SPI_MEM_OP_DATA_IN(1, nor->bouncebuf, 1));
+		CYPRESS_NOR_RD_ANY_REG_OP(3, SPINOR_REG_CYPRESS_CFR3V,
+					  nor->bouncebuf);
 	int ret;
 
+	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 	ret = spi_mem_exec_op(nor->spimem, &op);
 	if (ret)
 		return ret;
@@ -317,11 +328,7 @@ static void spansion_nor_clear_sr(struct spi_nor *nor)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_NO_DATA);
+		struct spi_mem_op op = SPANSION_CLSR_OP;
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
diff --git a/drivers/mtd/spi-nor/winbond.c b/drivers/mtd/spi-nor/winbond.c
index fe80dffc2e70..ffaa24055259 100644
--- a/drivers/mtd/spi-nor/winbond.c
+++ b/drivers/mtd/spi-nor/winbond.c
@@ -8,6 +8,15 @@
 
 #include "core.h"
 
+#define WINBOND_NOR_OP_RDEAR	0xc8	/* Read Extended Address Register */
+#define WINBOND_NOR_OP_WREAR	0xc5	/* Write Extended Address Register */
+
+#define WINBOND_NOR_WREAR_OP(buf)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(WINBOND_NOR_OP_WREAR, 0),		\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
+
 static int
 w25q256_post_bfpt_fixups(struct spi_nor *nor,
 			 const struct sfdp_parameter_header *bfpt_header,
@@ -124,12 +133,46 @@ static const struct flash_info winbond_nor_parts[] = {
 	{ "w25m512jv", INFO(0xef7119, 0, 64 * 1024, 1024)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_QUAD_READ |
 			      SPI_NOR_DUAL_READ) },
+	{ "w25q512nwm", INFO(0xef8020, 0, 64 * 1024, 1024)
+		PARSE_SFDP
+		OTP_INFO(256, 3, 0x1000, 0x1000) },
 	{ "w25q512jvq", INFO(0xef4020, 0, 64 * 1024, 1024)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ |
 			      SPI_NOR_QUAD_READ) },
 };
 
 /**
+ * winbond_nor_write_ear() - Write Extended Address Register.
+ * @nor:	pointer to 'struct spi_nor'.
+ * @ear:	value to write to the Extended Address Register.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int winbond_nor_write_ear(struct spi_nor *nor, u8 ear)
+{
+	int ret;
+
+	nor->bouncebuf[0] = ear;
+
+	if (nor->spimem) {
+		struct spi_mem_op op = WINBOND_NOR_WREAR_OP(nor->bouncebuf);
+
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
+		ret = spi_mem_exec_op(nor->spimem, &op);
+	} else {
+		ret = spi_nor_controller_ops_write_reg(nor,
+						       WINBOND_NOR_OP_WREAR,
+						       nor->bouncebuf, 1);
+	}
+
+	if (ret)
+		dev_dbg(nor->dev, "error %d writing EAR\n", ret);
+
+	return ret;
+}
+
+/**
  * winbond_nor_set_4byte_addr_mode() - Set 4-byte address mode for Winbond
  * flashes.
  * @nor:	pointer to 'struct spi_nor'.
@@ -155,7 +198,7 @@ static int winbond_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 	if (ret)
 		return ret;
 
-	ret = spi_nor_write_ear(nor, 0);
+	ret = winbond_nor_write_ear(nor, 0);
 	if (ret)
 		return ret;
 
diff --git a/drivers/mtd/spi-nor/xilinx.c b/drivers/mtd/spi-nor/xilinx.c
index 9459ac2609dc..1d2f5db047bd 100644
--- a/drivers/mtd/spi-nor/xilinx.c
+++ b/drivers/mtd/spi-nor/xilinx.c
@@ -15,6 +15,12 @@
 #define XSR_PAGESIZE		BIT(0)	/* Page size in Po2 or Linear */
 #define XSR_RDY			BIT(7)	/* Ready */
 
+#define XILINX_RDSR_OP(buf)						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(XILINX_OP_RDSR, 0),			\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, buf, 0))
+
 #define S3AN_INFO(_jedec_id, _n_sectors, _page_size)			\
 		.id = {							\
 			((_jedec_id) >> 16) & 0xff,			\
@@ -72,11 +78,7 @@ static int xilinx_nor_read_sr(struct spi_nor *nor, u8 *sr)
 	int ret;
 
 	if (nor->spimem) {
-		struct spi_mem_op op =
-			SPI_MEM_OP(SPI_MEM_OP_CMD(XILINX_OP_RDSR, 0),
-				   SPI_MEM_OP_NO_ADDR,
-				   SPI_MEM_OP_NO_DUMMY,
-				   SPI_MEM_OP_DATA_IN(1, sr, 0));
+		struct spi_mem_op op = XILINX_RDSR_OP(sr);
 
 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);