From 95954f55e91af538cce19fea4a731cc3474de6ff Mon Sep 17 00:00:00 2001
From: Pratyush Yadav
Date: Sat, 26 Jun 2021 00:47:16 +0530
Subject: mtd: spi-nor-core: Add support for DTR protocol
Double Transfer Rate (DTR) is SPI protocol in which data is transferred
on each clock edge as opposed to on each clock cycle. Make
framework-level changes to allow supporting flashes in DTR mode.
Right now, mixed DTR modes are not supported. So, for example a mode
like 4S-4D-4D will not work. All phases need to be either DTR or STR.
Signed-off-by: Pratyush Yadav
Reviewed-by: Jagan Teki
---
include/linux/mtd/spi-nor.h | 50 ++++++++++++++++++++++++++++++++++-----------
1 file changed, 38 insertions(+), 12 deletions(-)
(limited to 'include/linux/mtd')
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 90b75ec845..4394cb6e16 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -200,6 +200,7 @@ enum spi_nor_protocol {
SNOR_PROTO_1_2_2_DTR = SNOR_PROTO_DTR(1, 2, 2),
SNOR_PROTO_1_4_4_DTR = SNOR_PROTO_DTR(1, 4, 4),
SNOR_PROTO_1_8_8_DTR = SNOR_PROTO_DTR(1, 8, 8),
+ SNOR_PROTO_8_8_8_DTR = SNOR_PROTO_DTR(8, 8, 8),
};
static inline bool spi_nor_protocol_is_dtr(enum spi_nor_protocol proto)
@@ -267,7 +268,7 @@ struct spi_nor_hwcaps {
* then Quad SPI protocols before Dual SPI protocols, Fast Read and lastly
* (Slow) Read.
*/
-#define SNOR_HWCAPS_READ_MASK GENMASK(14, 0)
+#define SNOR_HWCAPS_READ_MASK GENMASK(15, 0)
#define SNOR_HWCAPS_READ BIT(0)
#define SNOR_HWCAPS_READ_FAST BIT(1)
#define SNOR_HWCAPS_READ_1_1_1_DTR BIT(2)
@@ -284,11 +285,12 @@ struct spi_nor_hwcaps {
#define SNOR_HWCAPS_READ_4_4_4 BIT(9)
#define SNOR_HWCAPS_READ_1_4_4_DTR BIT(10)
-#define SNOR_HWCPAS_READ_OCTO GENMASK(14, 11)
+#define SNOR_HWCPAS_READ_OCTO GENMASK(15, 11)
#define SNOR_HWCAPS_READ_1_1_8 BIT(11)
#define SNOR_HWCAPS_READ_1_8_8 BIT(12)
#define SNOR_HWCAPS_READ_8_8_8 BIT(13)
#define SNOR_HWCAPS_READ_1_8_8_DTR BIT(14)
+#define SNOR_HWCAPS_READ_8_8_8_DTR BIT(15)
/*
* Page Program capabilities.
@@ -299,18 +301,19 @@ struct spi_nor_hwcaps {
* JEDEC/SFDP standard to define them. Also at this moment no SPI flash memory
* implements such commands.
*/
-#define SNOR_HWCAPS_PP_MASK GENMASK(22, 16)
-#define SNOR_HWCAPS_PP BIT(16)
+#define SNOR_HWCAPS_PP_MASK GENMASK(23, 16)
+#define SNOR_HWCAPS_PP BIT(16)
-#define SNOR_HWCAPS_PP_QUAD GENMASK(19, 17)
-#define SNOR_HWCAPS_PP_1_1_4 BIT(17)
-#define SNOR_HWCAPS_PP_1_4_4 BIT(18)
-#define SNOR_HWCAPS_PP_4_4_4 BIT(19)
+#define SNOR_HWCAPS_PP_QUAD GENMASK(19, 17)
+#define SNOR_HWCAPS_PP_1_1_4 BIT(17)
+#define SNOR_HWCAPS_PP_1_4_4 BIT(18)
+#define SNOR_HWCAPS_PP_4_4_4 BIT(19)
-#define SNOR_HWCAPS_PP_OCTO GENMASK(22, 20)
-#define SNOR_HWCAPS_PP_1_1_8 BIT(20)
-#define SNOR_HWCAPS_PP_1_8_8 BIT(21)
-#define SNOR_HWCAPS_PP_8_8_8 BIT(22)
+#define SNOR_HWCAPS_PP_OCTO GENMASK(23, 20)
+#define SNOR_HWCAPS_PP_1_1_8 BIT(20)
+#define SNOR_HWCAPS_PP_1_8_8 BIT(21)
+#define SNOR_HWCAPS_PP_8_8_8 BIT(22)
+#define SNOR_HWCAPS_PP_8_8_8_DTR BIT(23)
#define SNOR_HWCAPS_X_X_X (SNOR_HWCAPS_READ_2_2_2 | \
SNOR_HWCAPS_READ_4_4_4 | \
@@ -318,6 +321,9 @@ struct spi_nor_hwcaps {
SNOR_HWCAPS_PP_4_4_4 | \
SNOR_HWCAPS_PP_8_8_8)
+#define SNOR_HWCAPS_X_X_X_DTR (SNOR_HWCAPS_READ_8_8_8_DTR | \
+ SNOR_HWCAPS_PP_8_8_8_DTR)
+
#define SNOR_HWCAPS_DTR (SNOR_HWCAPS_READ_1_1_1_DTR | \
SNOR_HWCAPS_READ_1_2_2_DTR | \
SNOR_HWCAPS_READ_1_4_4_DTR | \
@@ -360,6 +366,7 @@ enum spi_nor_read_command_index {
SNOR_CMD_READ_1_8_8,
SNOR_CMD_READ_8_8_8,
SNOR_CMD_READ_1_8_8_DTR,
+ SNOR_CMD_READ_8_8_8_DTR,
SNOR_CMD_READ_MAX
};
@@ -376,6 +383,7 @@ enum spi_nor_pp_command_index {
SNOR_CMD_PP_1_1_8,
SNOR_CMD_PP_1_8_8,
SNOR_CMD_PP_8_8_8,
+ SNOR_CMD_PP_8_8_8_DTR,
SNOR_CMD_PP_MAX
};
@@ -391,6 +399,22 @@ struct spi_nor_flash_parameter {
int (*quad_enable)(struct spi_nor *nor);
};
+/**
+ * enum spi_nor_cmd_ext - describes the command opcode extension in DTR mode
+ * @SPI_MEM_NOR_NONE: no extension. This is the default, and is used in Legacy
+ * SPI mode
+ * @SPI_MEM_NOR_REPEAT: the extension is same as the opcode
+ * @SPI_MEM_NOR_INVERT: the extension is the bitwise inverse of the opcode
+ * @SPI_MEM_NOR_HEX: the extension is any hex value. The command and opcode
+ * combine to form a 16-bit opcode.
+ */
+enum spi_nor_cmd_ext {
+ SPI_NOR_EXT_NONE = 0,
+ SPI_NOR_EXT_REPEAT,
+ SPI_NOR_EXT_INVERT,
+ SPI_NOR_EXT_HEX,
+};
+
/**
* struct flash_info - Forward declaration of a structure used internally by
* spi_nor_scan()
@@ -430,6 +454,7 @@ struct spi_flash {
* @write_proto: the SPI protocol for write operations
* @reg_proto the SPI protocol for read_reg/write_reg/erase operations
* @cmd_buf: used by the write_reg
+ * @cmd_ext_type: the command opcode extension for DTR mode.
* @fixups: flash-specific fixup hooks.
* @prepare: [OPTIONAL] do some preparations for the
* read/write/erase/lock/unlock operations
@@ -472,6 +497,7 @@ struct spi_nor {
bool sst_write_second;
u32 flags;
u8 cmd_buf[SPI_NOR_MAX_CMD_SIZE];
+ enum spi_nor_cmd_ext cmd_ext_type;
struct spi_nor_fixups *fixups;
int (*setup)(struct spi_nor *nor, const struct flash_info *info,
--
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