[PATCH v2] mtd: spi-nor: use spi-mem dirmap API

Sergei Shtylyov sergei.shtylyov at cogentembedded.com
Thu Nov 7 12:49:12 PST 2019


Make use of the spi-mem direct mapping API to let advanced controllers
optimize read/write operations when they support direct mapping.

Based on the original patch by Boris Brezillon <boris.brezillon at bootlin.com>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov at cogentembedded.com>

---
Changes in version 2:
- moved the spi_mem_dirmap_{read|write}() calls from spi_nor_{read|write}() to
  spi_nor_spimem_{read|write}_data().

 drivers/mtd/spi-nor/spi-nor.c |  125 +++++++++++++++++++++++++++++++++---------
 include/linux/mtd/spi-nor.h   |    5 +
 2 files changed, 104 insertions(+), 26 deletions(-)

Index: linux/drivers/mtd/spi-nor/spi-nor.c
===================================================================
--- linux.orig/drivers/mtd/spi-nor/spi-nor.c
+++ linux/drivers/mtd/spi-nor/spi-nor.c
@@ -305,22 +305,28 @@ static ssize_t spi_nor_spimem_xfer_data(
 static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
 					size_t len, u8 *buf)
 {
-	struct spi_mem_op op =
-		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
-			   SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
-			   SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
-			   SPI_MEM_OP_DATA_IN(len, buf, 1));
-
-	/* get transfer protocols. */
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
-	op.dummy.buswidth = op.addr.buswidth;
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
+	if (!nor->dirmap.rdesc) {
+		struct spi_mem_op op =
+			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
+				   SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
+				   SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
+				   SPI_MEM_OP_DATA_IN(len, buf, 1));
+
+		/* get transfer protocols. */
+		op.cmd.buswidth =
+			spi_nor_get_protocol_inst_nbits(nor->read_proto);
+		op.addr.buswidth =
+			spi_nor_get_protocol_addr_nbits(nor->read_proto);
+		op.dummy.buswidth = op.addr.buswidth;
+		op.data.buswidth =
+			spi_nor_get_protocol_data_nbits(nor->read_proto);
 
-	/* convert the dummy cycles to the number of bytes */
-	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
+		/* convert the dummy cycles to the number of bytes */
+		op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
 
-	return spi_nor_spimem_xfer_data(nor, &op);
+		return spi_nor_spimem_xfer_data(nor, &op);
+	}
+	return spi_mem_dirmap_read(nor->dirmap.rdesc, from, len, buf);
 }
 
 /**
@@ -354,20 +360,27 @@ static ssize_t spi_nor_read_data(struct
 static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
 					 size_t len, const u8 *buf)
 {
-	struct spi_mem_op op =
-		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
-			   SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
-			   SPI_MEM_OP_NO_DUMMY,
-			   SPI_MEM_OP_DATA_OUT(len, buf, 1));
-
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
+	if (!nor->dirmap.wdesc) {
+		struct spi_mem_op op =
+			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
+				   SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
+				   SPI_MEM_OP_NO_DUMMY,
+				   SPI_MEM_OP_DATA_OUT(len, buf, 1));
 
-	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
-		op.addr.nbytes = 0;
+		op.cmd.buswidth =
+			spi_nor_get_protocol_inst_nbits(nor->write_proto);
+		op.addr.buswidth =
+			spi_nor_get_protocol_addr_nbits(nor->write_proto);
+		op.data.buswidth =
+			spi_nor_get_protocol_data_nbits(nor->write_proto);
+
+		if (nor->program_opcode == SPINOR_OP_AAI_WP &&
+		    nor->sst_write_second)
+			op.addr.nbytes = 0;
 
-	return spi_nor_spimem_xfer_data(nor, &op);
+		return spi_nor_spimem_xfer_data(nor, &op);
+	}
+	return spi_mem_dirmap_write(nor->dirmap.wdesc, to, len, buf);
 }
 
 /**
@@ -4979,6 +4992,58 @@ int spi_nor_scan(struct spi_nor *nor, co
 }
 EXPORT_SYMBOL_GPL(spi_nor_scan);
 
+static int spi_nor_create_read_dirmap(struct spi_nor *nor)
+{
+	struct spi_mem_dirmap_info info = {
+		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
+				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 1),
+				      SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
+				      SPI_MEM_OP_DATA_IN(0, NULL, 1)),
+		.offset = 0,
+		.length = nor->mtd.size,
+	};
+	struct spi_mem_op *op = &info.op_tmpl;
+
+	/* get transfer protocols. */
+	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
+	op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
+	op->dummy.buswidth = op->addr.buswidth;
+	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
+
+	/* convert the dummy cycles to the number of bytes */
+	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
+
+	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
+						       &info);
+	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
+}
+
+static int spi_nor_create_write_dirmap(struct spi_nor *nor)
+{
+	struct spi_mem_dirmap_info info = {
+		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
+				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 1),
+				      SPI_MEM_OP_NO_DUMMY,
+				      SPI_MEM_OP_DATA_OUT(0, NULL, 1)),
+		.offset = 0,
+		.length = nor->mtd.size,
+	};
+	struct spi_mem_op *op = &info.op_tmpl;
+
+	/* get transfer protocols. */
+	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
+	op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
+	op->dummy.buswidth = op->addr.buswidth;
+	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
+
+	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
+		op->addr.nbytes = 0;
+
+	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
+						       &info);
+	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
+}
+
 static int spi_nor_probe(struct spi_mem *spimem)
 {
 	struct spi_device *spi = spimem->spi;
@@ -5040,6 +5105,14 @@ static int spi_nor_probe(struct spi_mem
 			return -ENOMEM;
 	}
 
+	ret = spi_nor_create_read_dirmap(nor);
+	if (ret)
+		return ret;
+
+	ret = spi_nor_create_write_dirmap(nor);
+	if (ret)
+		return ret;
+
 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
 				   data ? data->nr_parts : 0);
 }
Index: linux/include/linux/mtd/spi-nor.h
===================================================================
--- linux.orig/include/linux/mtd/spi-nor.h
+++ linux/include/linux/mtd/spi-nor.h
@@ -602,6 +602,11 @@ struct spi_nor {
 	int (*clear_sr_bp)(struct spi_nor *nor);
 	struct spi_nor_flash_parameter params;
 
+	struct {
+		struct spi_mem_dirmap_desc *rdesc;
+		struct spi_mem_dirmap_desc *wdesc;
+	} dirmap;
+
 	void *priv;
 };
 



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