[PATCH 3/5] mtd: spinand: Add support for packed read data ODTR commands

[Miquel Raynal]

Some devices stuff address bits in the double byte opcode (in place of
the repeated byte) in order to be able to increase the size of the
devices, without adding extra address bytes.

Create a flag to identify those devices. When the flag is set, use the
"packed" variant for the read data operation.

Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
 drivers/mtd/nand/spi/core.c | 24 +++++++++++++++++++++---
 include/linux/mtd/spinand.h |  7 +++++++
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 66c90419f6d5..96154f359e1a 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -100,6 +100,17 @@ spinand_fill_page_read_op(struct spinand_device *spinand, u64 addr)
 	return op;
 }
 
+static struct spi_mem_op
+spinand_fill_page_read_packed_op(struct spinand_device *spinand, u64 addr)
+{
+	struct spi_mem_op op = spinand->op_templates->page_read;
+
+	op.cmd.opcode |= addr >> 16;
+	op.addr.val = addr & 0xFFFF;
+
+	return op;
+}
+
 struct spi_mem_op
 spinand_fill_prog_exec_op(struct spinand_device *spinand, u64 addr)
 {
@@ -453,7 +464,10 @@ static int spinand_load_page_op(struct spinand_device *spinand,
 {
 	struct nand_device *nand = spinand_to_nand(spinand);
 	unsigned int row = nanddev_pos_to_row(nand, &req->pos);
-	struct spi_mem_op op = SPINAND_OP(spinand, page_read, row);
+	bool packed = spinand->flags & SPINAND_ODTR_PACKED_PAGE_READ;
+	struct spi_mem_op op = packed ?
+		SPINAND_OP(spinand, page_read_packed, row) :
+		SPINAND_OP(spinand, page_read, row);
 
 	return spi_mem_exec_op(spinand->spimem, &op);
 }
@@ -1489,9 +1503,13 @@ static int spinand_init_odtr_instruction_set(struct spinand_device *spinand)
 	if (!spi_mem_supports_op(spinand->spimem, &tmpl->blk_erase))
 		return -EOPNOTSUPP;
 
-	tmpl->page_read = (struct spi_mem_op)SPINAND_PAGE_READ_8D_8D_0_OP(0);
-	if (!spi_mem_supports_op(spinand->spimem, &tmpl->page_read))
+	if (spinand->flags & SPINAND_ODTR_PACKED_PAGE_READ)
+		tmpl->page_read = (struct spi_mem_op)SPINAND_PAGE_READ_PACKED_8D_8D_0_OP(0);
+	else
+		tmpl->page_read = (struct spi_mem_op)SPINAND_PAGE_READ_8D_8D_0_OP(0);
+	if (!spi_mem_supports_op(spinand->spimem, &tmpl->page_read)) {
 		return -EOPNOTSUPP;
+	}
 
 	tmpl->prog_exec = (struct spi_mem_op)SPINAND_PROG_EXEC_8D_8D_0_OP(0);
 	if (!spi_mem_supports_op(spinand->spimem, &tmpl->prog_exec))
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index 6a024cf1c53a..f2f80103649d 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -290,6 +290,12 @@
 		   SPI_MEM_OP_NO_DUMMY,					\
 		   SPI_MEM_OP_NO_DATA)
 
+#define SPINAND_PAGE_READ_PACKED_8D_8D_0_OP(addr)			\
+	SPI_MEM_OP(SPI_MEM_DTR_OP_PACKED_CMD(0x13, addr >> 16, 8),	\
+		   SPI_MEM_DTR_OP_ADDR(2, addr & 0xffff, 8),		\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
 #define SPINAND_PAGE_READ_FROM_CACHE_8D_8D_8D_OP(addr, ndummy, buf, len, freq) \
 	SPI_MEM_OP(SPI_MEM_DTR_OP_RPT_CMD(0x9d, 8),			\
 		   SPI_MEM_DTR_OP_ADDR(2, addr, 8),			\
@@ -482,6 +488,7 @@ struct spinand_ecc_info {
 #define SPINAND_HAS_PROG_PLANE_SELECT_BIT		BIT(2)
 #define SPINAND_HAS_READ_PLANE_SELECT_BIT		BIT(3)
 #define SPINAND_NO_RAW_ACCESS				BIT(4)
+#define SPINAND_ODTR_PACKED_PAGE_READ			BIT(5)
 
 /**
  * struct spinand_ondie_ecc_conf - private SPI-NAND on-die ECC engine structure

-- 
2.53.0