mtd: spi-nor: Use spi-mem dirmap API

This adds support for the dirmap API to the spi-nor subsystem, as
introduced in Linux commit df5c21002cf4  ("mtd: spi-nor: use
spi-mem dirmap API").

This patch is synchronize from the following patch
https://patchwork.ozlabs.org/project/uboot/patch/20210205043924.149504-4-seanga2@gmail.com/
The corresponding Linux kernel SHA1 is df5c21002cf4.

Signed-off-by: Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Acked-by: Pratyush Yadav <p.yadav@ti.com>

drivers/mtd/spi/sf_probe.c

@@ -10,13 +10,69 @@
 #include <common.h>
 #include <dm.h>
 #include <errno.h>
+#include <linux/mtd/spi-nor.h>
 #include <log.h>
 #include <malloc.h>
 #include <spi.h>
 #include <spi_flash.h>
+#include <spi-mem.h>
 
 #include "sf_internal.h"
 
+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, 0),
+				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 0),
+				      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
+				      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
+		.offset = 0,
+		.length = nor->mtd.size,
+	};
+	struct spi_mem_op *op = &info.op_tmpl;
+
+	/* get transfer protocols. */
+	spi_nor_setup_op(nor, op, nor->read_proto);
+	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;
+	if (spi_nor_protocol_is_dtr(nor->read_proto))
+		op->dummy.nbytes *= 2;
+
+	nor->dirmap.rdesc = spi_mem_dirmap_create(nor->spi, &info);
+	if (IS_ERR(nor->dirmap.rdesc))
+		return PTR_ERR(nor->dirmap.rdesc);
+
+	return 0;
+}
+
+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, 0),
+				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 0),
+				      SPI_MEM_OP_NO_DUMMY,
+				      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
+		.offset = 0,
+		.length = nor->mtd.size,
+	};
+	struct spi_mem_op *op = &info.op_tmpl;
+
+	/* get transfer protocols. */
+	spi_nor_setup_op(nor, op, 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;
+
+	nor->dirmap.wdesc = spi_mem_dirmap_create(nor->spi, &info);
+	if (IS_ERR(nor->dirmap.wdesc))
+		return PTR_ERR(nor->dirmap.wdesc);
+
+	return 0;
+}
+
 /**
  * spi_flash_probe_slave() - Probe for a SPI flash device on a bus
  *
@@ -45,6 +101,16 @@ static int spi_flash_probe_slave(struct spi_flash *flash)
 	if (ret)
 		goto err_read_id;
 
+	if (CONFIG_IS_ENABLED(SPI_DIRMAP)) {
+		ret = spi_nor_create_read_dirmap(flash);
+		if (ret)
+			return ret;
+
+		ret = spi_nor_create_write_dirmap(flash);
+		if (ret)
+			return ret;
+	}
+
 	if (CONFIG_IS_ENABLED(SPI_FLASH_MTD))
 		ret = spi_flash_mtd_register(flash);
 
@@ -83,6 +149,11 @@ struct spi_flash *spi_flash_probe(unsigned int busnum, unsigned int cs,
 
 void spi_flash_free(struct spi_flash *flash)
 {
+	if (CONFIG_IS_ENABLED(SPI_DIRMAP)) {
+		spi_mem_dirmap_destroy(flash->dirmap.wdesc);
+		spi_mem_dirmap_destroy(flash->dirmap.rdesc);
+	}
+
 	if (CONFIG_IS_ENABLED(SPI_FLASH_MTD))
 		spi_flash_mtd_unregister(flash);
 
@@ -153,6 +224,11 @@ static int spi_flash_std_remove(struct udevice *dev)
 	struct spi_flash *flash = dev_get_uclass_priv(dev);
 	int ret;
 
+	if (CONFIG_IS_ENABLED(SPI_DIRMAP)) {
+		spi_mem_dirmap_destroy(flash->dirmap.wdesc);
+		spi_mem_dirmap_destroy(flash->dirmap.rdesc);
+	}
+
 	ret = spi_nor_remove(flash);
 	if (ret)
 		return ret;

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

@@ -246,9 +246,9 @@ static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
  *			need to be initialized.
  * @proto:		the protocol from which the properties need to be set.
  */
-static void spi_nor_setup_op(const struct spi_nor *nor,
-			     struct spi_mem_op *op,
-			     const enum spi_nor_protocol proto)
+void spi_nor_setup_op(const struct spi_nor *nor,
+		      struct spi_mem_op *op,
+		      const enum spi_nor_protocol proto)
 {
 	u8 ext;
 
@@ -369,13 +369,29 @@ static ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len,
 
 	while (remaining) {
 		op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
-		ret = spi_mem_adjust_op_size(nor->spi, &op);
-		if (ret)
-			return ret;
 
-		ret = spi_mem_exec_op(nor->spi, &op);
-		if (ret)
-			return ret;
+		if (CONFIG_IS_ENABLED(SPI_DIRMAP) && nor->dirmap.rdesc) {
+			/*
+			 * Record current operation information which may be used
+			 * when the address or data length exceeds address mapping.
+			 */
+			memcpy(&nor->dirmap.rdesc->info.op_tmpl, &op,
+			       sizeof(struct spi_mem_op));
+			ret = spi_mem_dirmap_read(nor->dirmap.rdesc,
+						  op.addr.val, op.data.nbytes,
+						  op.data.buf.in);
+			if (ret < 0)
+				return ret;
+			op.data.nbytes = ret;
+		} else {
+			ret = spi_mem_adjust_op_size(nor->spi, &op);
+			if (ret)
+				return ret;
+
+			ret = spi_mem_exec_op(nor->spi, &op);
+			if (ret)
+				return ret;
+		}
 
 		op.addr.val += op.data.nbytes;
 		remaining -= op.data.nbytes;
@@ -400,14 +416,21 @@ static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
 
 	spi_nor_setup_op(nor, &op, nor->write_proto);
 
-	ret = spi_mem_adjust_op_size(nor->spi, &op);
-	if (ret)
-		return ret;
-	op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes;
+	if (CONFIG_IS_ENABLED(SPI_DIRMAP) && nor->dirmap.wdesc) {
+		memcpy(&nor->dirmap.wdesc->info.op_tmpl, &op,
+		       sizeof(struct spi_mem_op));
+		op.data.nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
+						      op.data.nbytes, op.data.buf.out);
+	} else {
+		ret = spi_mem_adjust_op_size(nor->spi, &op);
+		if (ret)
+			return ret;
+		op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes;
 
-	ret = spi_mem_exec_op(nor->spi, &op);
-	if (ret)
-		return ret;
+		ret = spi_mem_exec_op(nor->spi, &op);
+		if (ret)
+			return ret;
+	}
 
 	return op.data.nbytes;
 }

include/linux/mtd/spi-nor.h

@@ -11,6 +11,7 @@
 #include <linux/bitops.h>
 #include <linux/mtd/cfi.h>
 #include <linux/mtd/mtd.h>
+#include <spi-mem.h>
 
 /*
  * Manufacturer IDs
@@ -522,6 +523,7 @@ struct spi_flash {
  * @quad_enable:	[FLASH-SPECIFIC] enables SPI NOR quad mode
  * @octal_dtr_enable:	[FLASH-SPECIFIC] enables SPI NOR octal DTR mode.
  * @ready:		[FLASH-SPECIFIC] check if the flash is ready
+ * @dirmap:		pointers to struct spi_mem_dirmap_desc for reads/writes.
  * @priv:		the private data
  */
 struct spi_nor {
@@ -572,6 +574,11 @@ struct spi_nor {
 	int (*octal_dtr_enable)(struct spi_nor *nor);
 	int (*ready)(struct spi_nor *nor);
 
+	struct {
+		struct spi_mem_dirmap_desc *rdesc;
+		struct spi_mem_dirmap_desc *wdesc;
+	} dirmap;
+
 	void *priv;
 	char mtd_name[MTD_NAME_SIZE(MTD_DEV_TYPE_NOR)];
 /* Compatibility for spi_flash, remove once sf layer is merged with mtd */
@@ -595,6 +602,17 @@ device_node *spi_nor_get_flash_node(struct spi_nor *nor)
 }
 #endif /* __UBOOT__ */
 
+/**
+ * spi_nor_setup_op() - Set up common properties of a spi-mem op.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @op:			pointer to the 'struct spi_mem_op' whose properties
+ *			need to be initialized.
+ * @proto:		the protocol from which the properties need to be set.
+ */
+void spi_nor_setup_op(const struct spi_nor *nor,
+		      struct spi_mem_op *op,
+		      const enum spi_nor_protocol proto);
+
 /**
  * spi_nor_scan() - scan the SPI NOR
  * @nor:	the spi_nor structure