mtd: spi-nor-core: Add octal mode support

Add support for Octal flash devices. Octal flash devices use 8 IO lines
for data transfer. Currently only 1-1-8 Octal Read mode is supported.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>

drivers/mtd/spi/sf_internal.h

@@ -37,7 +37,7 @@ struct flash_info {
 	u16		page_size;
 	u16		addr_width;
 
-	u16		flags;
+	u32		flags;
 #define SECT_4K			BIT(0)	/* SPINOR_OP_BE_4K works uniformly */
 #define SPI_NOR_NO_ERASE	BIT(1)	/* No erase command needed */
 #define SST_WRITE		BIT(2)	/* use SST byte programming */
@@ -66,6 +66,7 @@ struct flash_info {
 #define SPI_NOR_SKIP_SFDP	BIT(13)	/* Skip parsing of SFDP tables */
 #define USE_CLSR		BIT(14)	/* use CLSR command */
 #define SPI_NOR_HAS_SST26LOCK	BIT(15)	/* Flash supports lock/unlock via BPR */
+#define SPI_NOR_OCTAL_READ      BIT(16) /* Flash supports Octal Read */
 };
 
 extern const struct flash_info spi_nor_ids[];

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

@@ -251,6 +251,8 @@ static u8 spi_nor_convert_3to4_read(u8 opcode)
 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
+		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
+		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
 
 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
@@ -267,6 +269,8 @@ static u8 spi_nor_convert_3to4_program(u8 opcode)
 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
+		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
+		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
 	};
 
 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
@@ -2169,6 +2173,13 @@ static int spi_nor_init_params(struct spi_nor *nor,
 					  SNOR_PROTO_1_1_4);
 	}
 
+	if (info->flags & SPI_NOR_OCTAL_READ) {
+		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
+		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
+					  0, 8, SPINOR_OP_READ_1_1_8,
+					  SNOR_PROTO_1_1_8);
+	}
+
 	/* Page Program settings. */
 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
@@ -2476,7 +2487,14 @@ int spi_nor_scan(struct spi_nor *nor)
 	nor->read_reg = spi_nor_read_reg;
 	nor->write_reg = spi_nor_write_reg;
 
-	if (spi->mode & SPI_RX_QUAD) {
+	if (spi->mode & SPI_RX_OCTAL) {
+		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
+
+		if (spi->mode & SPI_TX_OCTAL)
+			hwcaps.mask |= (SNOR_HWCAPS_READ_1_8_8 |
+					SNOR_HWCAPS_PP_1_1_8 |
+					SNOR_HWCAPS_PP_1_8_8);
+	} else if (spi->mode & SPI_RX_QUAD) {
 		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
 
 		if (spi->mode & SPI_TX_QUAD)

drivers/spi/spi-mem.c

@@ -123,6 +123,12 @@ static int spi_check_buswidth_req(struct spi_slave *slave, u8 buswidth, bool tx)
 			return 0;
 
 		break;
+	case 8:
+		if ((tx && (mode & SPI_TX_OCTAL)) ||
+		    (!tx && (mode & SPI_RX_OCTAL)))
+			return 0;
+
+		break;
 
 	default:
 		break;

drivers/spi/spi-uclass.c

@@ -461,6 +461,9 @@ int spi_slave_ofdata_to_platdata(struct udevice *dev,
 	case 4:
 		mode |= SPI_TX_QUAD;
 		break;
+	case 8:
+		mode |= SPI_TX_OCTAL;
+		break;
 	default:
 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
 		break;
@@ -476,6 +479,9 @@ int spi_slave_ofdata_to_platdata(struct udevice *dev,
 	case 4:
 		mode |= SPI_RX_QUAD;
 		break;
+	case 8:
+		mode |= SPI_RX_OCTAL;
+		break;
 	default:
 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
 		break;

include/linux/mtd/spi-nor.h

@@ -47,9 +47,13 @@
 #define SPINOR_OP_READ_1_2_2	0xbb	/* Read data bytes (Dual I/O SPI) */
 #define SPINOR_OP_READ_1_1_4	0x6b	/* Read data bytes (Quad Output SPI) */
 #define SPINOR_OP_READ_1_4_4	0xeb	/* Read data bytes (Quad I/O SPI) */
+#define SPINOR_OP_READ_1_1_8	0x8b    /* Read data bytes (Octal Output SPI) */
+#define SPINOR_OP_READ_1_8_8	0xcb    /* Read data bytes (Octal I/O SPI) */
 #define SPINOR_OP_PP		0x02	/* Page program (up to 256 bytes) */
 #define SPINOR_OP_PP_1_1_4	0x32	/* Quad page program */
 #define SPINOR_OP_PP_1_4_4	0x38	/* Quad page program */
+#define SPINOR_OP_PP_1_1_8	0x82    /* Octal page program */
+#define SPINOR_OP_PP_1_8_8	0xc2    /* Octal page program */
 #define SPINOR_OP_BE_4K		0x20	/* Erase 4KiB block */
 #define SPINOR_OP_BE_4K_PMC	0xd7	/* Erase 4KiB block on PMC chips */
 #define SPINOR_OP_BE_32K	0x52	/* Erase 32KiB block */
@@ -70,9 +74,13 @@
 #define SPINOR_OP_READ_1_2_2_4B	0xbc	/* Read data bytes (Dual I/O SPI) */
 #define SPINOR_OP_READ_1_1_4_4B	0x6c	/* Read data bytes (Quad Output SPI) */
 #define SPINOR_OP_READ_1_4_4_4B	0xec	/* Read data bytes (Quad I/O SPI) */
+#define SPINOR_OP_READ_1_1_8_4B	0x7c    /* Read data bytes (Octal Output SPI) */
+#define SPINOR_OP_READ_1_8_8_4B	0xcc    /* Read data bytes (Octal I/O SPI) */
 #define SPINOR_OP_PP_4B		0x12	/* Page program (up to 256 bytes) */
 #define SPINOR_OP_PP_1_1_4_4B	0x34	/* Quad page program */
 #define SPINOR_OP_PP_1_4_4_4B	0x3e	/* Quad page program */
+#define SPINOR_OP_PP_1_1_8_4B	0x84    /* Octal page program */
+#define SPINOR_OP_PP_1_8_8_4B	0x8e    /* Octal page program */
 #define SPINOR_OP_BE_4K_4B	0x21	/* Erase 4KiB block */
 #define SPINOR_OP_BE_32K_4B	0x5c	/* Erase 32KiB block */
 #define SPINOR_OP_SE_4B		0xdc	/* Sector erase (usually 64KiB) */

include/spi.h

@@ -30,6 +30,8 @@
 #define SPI_RX_SLOW	BIT(11)			/* receive with 1 wire slow */
 #define SPI_RX_DUAL	BIT(12)			/* receive with 2 wires */
 #define SPI_RX_QUAD	BIT(13)			/* receive with 4 wires */
+#define SPI_TX_OCTAL	BIT(14)			/* transmit with 8 wires */
+#define SPI_RX_OCTAL	BIT(15)			/* receive with 8 wires */
 
 /* Header byte that marks the start of the message */
 #define SPI_PREAMBLE_END_BYTE	0xec