[PATCH v3 2/2] mtd: spi-nor: spansion: Add support for Infineon S25FS256T

[tkuw584924 at gmail.com]

From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>

Infineon S25FS256T is 256Mbit Quad SPI NOR flash. The key features and
differences comparing to other Spansion/Cypress flash familes are:
  - 4-byte address mode by factory default
  - Quad mode is enabled by factory default
  - OP_READ_FAST_4B(0Ch) is not supported
  - Supports mixture of 128KB and 64KB sectors by OTP configuration
    (this patch supports uniform 128KB only due to complexity of
     non-uniform layout)

Tested on Xilinx Zynq-7000 FPGA board.

Link: https://www.infineon.com/dgdlac/Infineon-S25FS256T_256Mb_SEMPER_Nano_Flash_Quad_SPI_1.8V-DataSheet-v12_00-EN.pdf?fileId=8ac78c8c80027ecd0180740c5a46707a
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
---
Changes in v3:
  - add params->addr_nbytes = 4 in post_bfpt
  - give 'ndummy' to RD_ANY_REG_OP in post_bfpt
  - s/SFDP/4BAIT in post_sfdp 

Changes in v2:
  - s/EOPNOTSUPP/ENODEV
  - Drop READ_FAST support
  - Amend comment in late_init()
  - sector size and page size as 0 in sizeINFO6()

---
 drivers/mtd/spi-nor/spansion.c | 60 ++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/drivers/mtd/spi-nor/spansion.c b/drivers/mtd/spi-nor/spansion.c
index 9faab29aba57..1678b7b2e9f7 100644
--- a/drivers/mtd/spi-nor/spansion.c
+++ b/drivers/mtd/spi-nor/spansion.c
@@ -29,6 +29,7 @@
 	 SPINOR_REG_CYPRESS_CFR5_OPI)
 #define SPINOR_REG_CYPRESS_CFR5_OCT_DTR_DS	SPINOR_REG_CYPRESS_CFR5_BIT6
 #define SPINOR_OP_CYPRESS_RD_FAST		0xee
+#define SPINOR_REG_CYPRESS_ARCFN		0x00000006
 
 /* Cypress SPI NOR flash operations. */
 #define CYPRESS_NOR_WR_ANY_REG_OP(naddr, addr, ndata, buf)		\
@@ -218,6 +219,62 @@ static int cypress_nor_set_page_size(struct spi_nor *nor)
 	return 0;
 }
 
+static int
+s25fs256t_post_bfpt_fixup(struct spi_nor *nor,
+			  const struct sfdp_parameter_header *bfpt_header,
+			  const struct sfdp_bfpt *bfpt)
+{
+	struct spi_mem_op op;
+	int ret;
+
+	/* 4-byte address mode is enabled by default */
+	nor->params->addr_nbytes = 4;
+	nor->params->addr_mode_nbytes = 4;
+
+	/* Read Architecture Configuration Register (ARCFN) */
+	op = (struct spi_mem_op)
+		CYPRESS_NOR_RD_ANY_REG_OP(nor->params->addr_mode_nbytes,
+					  SPINOR_REG_CYPRESS_ARCFN, 1,
+					  nor->bouncebuf);
+	ret = spi_nor_read_any_reg(nor, &op, nor->reg_proto);
+	if (ret)
+		return ret;
+
+	/* ARCFN value must be 0 if uniform sector is selected  */
+	if (nor->bouncebuf[0])
+		return -ENODEV;
+
+	return cypress_nor_set_page_size(nor);
+}
+
+static void s25fs256t_post_sfdp_fixup(struct spi_nor *nor)
+{
+	struct spi_nor_flash_parameter *params = nor->params;
+
+	/* PP_1_1_4_4B is supported but missing in 4BAIT. */
+	params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
+	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
+				SPINOR_OP_PP_1_1_4_4B,
+				SNOR_PROTO_1_1_4);
+}
+
+static void s25fs256t_late_init(struct spi_nor *nor)
+{
+	/*
+	 * Programming is supported only in 16-byte ECC data unit granularity.
+	 * Byte-programming, bit-walking, or multiple program operations to the
+	 * same ECC data unit without an erase are not allowed. See chapter
+	 * 5.3.1 and 5.6 in the datasheet.
+	 */
+	nor->params->writesize = 16;
+}
+
+static struct spi_nor_fixups s25fs256t_fixups = {
+	.post_bfpt = s25fs256t_post_bfpt_fixup,
+	.post_sfdp = s25fs256t_post_sfdp_fixup,
+	.late_init = s25fs256t_late_init,
+};
+
 static int
 s25hx_t_post_bfpt_fixup(struct spi_nor *nor,
 			const struct sfdp_parameter_header *bfpt_header,
@@ -446,6 +503,9 @@ static const struct flash_info spansion_nor_parts[] = {
 	{ "s25fl256l",  INFO(0x016019,      0,  64 * 1024, 512)
 		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)
 		FIXUP_FLAGS(SPI_NOR_4B_OPCODES) },
+	{ "s25fs256t",  INFO6(0x342b19, 0x0f0890, 0, 0)
+		PARSE_SFDP
+		.fixups = &s25fs256t_fixups },
 	{ "s25hl512t",  INFO6(0x342a1a, 0x0f0390, 256 * 1024, 256)
 		PARSE_SFDP
 		MFR_FLAGS(USE_CLSR)
-- 
2.25.1