mtd: spi-nor: spansion: switch cypress_nor_get_page_size() to use vreg_offset

All users of cypress_nor_get_page_size() but S25FS256T retrieve n_dice
and vreg_offset from SFDP. S25FS256T does not define the SCCR map to
retrive the vreg_offset, but it does support it: SPINOR_REG_CYPRESS_VREG.
Switch cypress_nor_get_page_size() to always use vreg_offset so that we
use the same code base for both single and multi chip package flashes.
cypress_nor_get_page_size() is now called in the post_sfdp() hook instead
of post_bfpt(), as vreg_offset and n_dice are parsed after BFPT.
Consequently the null checks on n_dice and vreg_offset are moved to
the post_sfdp() hook.

Tested-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Link: https://lore.kernel.org/r/20230726075257.12985-12-tudor.ambarus@linaro.org
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>

Author: ambarus

drivers/mtd/spi-nor/spansion.c

@@ -32,8 +32,6 @@
 #define SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24	0xb
 #define SPINOR_REG_CYPRESS_CFR2_ADRBYT		BIT(7)
 #define SPINOR_REG_CYPRESS_CFR3			0x4
-#define SPINOR_REG_CYPRESS_CFR3V					\
-	(SPINOR_REG_CYPRESS_VREG + SPINOR_REG_CYPRESS_CFR3)
 #define SPINOR_REG_CYPRESS_CFR3_PGSZ		BIT(4) /* Page size. */
 #define SPINOR_REG_CYPRESS_CFR5			0x6
 #define SPINOR_REG_CYPRESS_CFR5_BIT6		BIT(6)
@@ -467,28 +465,17 @@ static int cypress_nor_set_addr_mode_nbytes(struct spi_nor *nor)
 	return 0;
 }
 
-static int cypress_nor_get_page_size_single_chip(struct spi_nor *nor)
-{
-	struct spi_mem_op op =
-		CYPRESS_NOR_RD_ANY_REG_OP(nor->params->addr_mode_nbytes,
-					  SPINOR_REG_CYPRESS_CFR3V, 0,
-					  nor->bouncebuf);
-	int ret;
-
-	ret = spi_nor_read_any_reg(nor, &op, nor->reg_proto);
-	if (ret)
-		return ret;
-
-	if (nor->bouncebuf[0] & SPINOR_REG_CYPRESS_CFR3_PGSZ)
-		nor->params->page_size = 512;
-	else
-		nor->params->page_size = 256;
-
-	return 0;
-}
-
-
-static int cypress_nor_get_page_size_mcp(struct spi_nor *nor)
+/**
+ * cypress_nor_get_page_size() - Get flash page size configuration.
+ * @nor:	pointer to a 'struct spi_nor'
+ *
+ * The BFPT table advertises a 512B or 256B page size depending on part but the
+ * page size is actually configurable (with the default being 256B). Read from
+ * CFR3V[4] and set the correct size.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int cypress_nor_get_page_size(struct spi_nor *nor)
 {
 	struct spi_mem_op op =
 		CYPRESS_NOR_RD_ANY_REG_OP(nor->params->addr_mode_nbytes,
@@ -518,23 +505,6 @@ static int cypress_nor_get_page_size_mcp(struct spi_nor *nor)
 	return 0;
 }
 
-/**
- * cypress_nor_get_page_size() - Get flash page size configuration.
- * @nor:	pointer to a 'struct spi_nor'
- *
- * The BFPT table advertises a 512B or 256B page size depending on part but the
- * page size is actually configurable (with the default being 256B). Read from
- * CFR3V[4] and set the correct size.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int cypress_nor_get_page_size(struct spi_nor *nor)
-{
-	if (nor->params->n_dice)
-		return cypress_nor_get_page_size_mcp(nor);
-	return cypress_nor_get_page_size_single_chip(nor);
-}
-
 static void cypress_nor_ecc_init(struct spi_nor *nor)
 {
 	/*
@@ -571,20 +541,32 @@ s25fs256t_post_bfpt_fixup(struct spi_nor *nor,
 	if (nor->bouncebuf[0])
 		return -ENODEV;
 
-	return cypress_nor_get_page_size(nor);
+	return 0;
 }
 
 static int s25fs256t_post_sfdp_fixup(struct spi_nor *nor)
 {
 	struct spi_nor_flash_parameter *params = nor->params;
 
+	/*
+	 * S25FS256T does not define the SCCR map, but we would like to use the
+	 * same code base for both single and multi chip package devices, thus
+	 * set the vreg_offset and n_dice to be able to do so.
+	 */
+	params->vreg_offset = devm_kmalloc(nor->dev, sizeof(u32), GFP_KERNEL);
+	if (!params->vreg_offset)
+		return -ENOMEM;
+
+	params->vreg_offset[0] = SPINOR_REG_CYPRESS_VREG;
+	params->n_dice = 1;
+
 	/* 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);
 
-	return 0;
+	return cypress_nor_get_page_size(nor);
 }
 
 static int s25fs256t_late_init(struct spi_nor *nor)
@@ -619,10 +601,20 @@ s25hx_t_post_bfpt_fixup(struct spi_nor *nor,
 
 static int s25hx_t_post_sfdp_fixup(struct spi_nor *nor)
 {
-	struct spi_nor_erase_type *erase_type =
-					nor->params->erase_map.erase_type;
+	struct spi_nor_flash_parameter *params = nor->params;
+	struct spi_nor_erase_type *erase_type = params->erase_map.erase_type;
 	unsigned int i;
 
+	if (!params->n_dice || !params->vreg_offset) {
+		dev_err(nor->dev, "%s failed. The volatile register offset could not be retrieved from SFDP.\n",
+			__func__);
+		return -EOPNOTSUPP;
+	}
+
+	/* The 2 Gb parts duplicate info and advertise 4 dice instead of 2. */
+	if (params->size == SZ_256M)
+		params->n_dice = 2;
+
 	/*
 	 * In some parts, 3byte erase opcodes are advertised by 4BAIT.
 	 * Convert them to 4byte erase opcodes.
@@ -640,23 +632,13 @@ static int s25hx_t_post_sfdp_fixup(struct spi_nor *nor)
 		}
 	}
 
-	/* The 2 Gb parts duplicate info and advertise 4 dice instead of 2. */
-	if (nor->params->size == SZ_256M)
-		nor->params->n_dice = 2;
-
 	return cypress_nor_get_page_size(nor);
 }
 
 static int s25hx_t_late_init(struct spi_nor *nor)
 {
 	struct spi_nor_flash_parameter *params = nor->params;
 
-	if (!params->n_dice || !params->vreg_offset) {
-		dev_err(nor->dev, "%s failed. The volatile register offset could not be retrieved from SFDP.\n",
-			__func__);
-		return -EOPNOTSUPP;
-	}
-
 	/* Fast Read 4B requires mode cycles */
 	params->reads[SNOR_CMD_READ_FAST].num_mode_clocks = 8;
 	params->ready = cypress_nor_sr_ready_and_clear;
@@ -690,6 +672,17 @@ static int cypress_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
 static int s28hx_t_post_sfdp_fixup(struct spi_nor *nor)
 {
 	struct spi_nor_flash_parameter *params = nor->params;
+
+	if (!params->n_dice || !params->vreg_offset) {
+		dev_err(nor->dev, "%s failed. The volatile register offset could not be retrieved from SFDP.\n",
+			__func__);
+		return -EOPNOTSUPP;
+	}
+
+	/* The 2 Gb parts duplicate info and advertise 4 dice instead of 2. */
+	if (params->size == SZ_256M)
+		params->n_dice = 2;
+
 	/*
 	 * On older versions of the flash the xSPI Profile 1.0 table has the
 	 * 8D-8D-8D Fast Read opcode as 0x00. But it actually should be 0xEE.
@@ -715,10 +708,6 @@ static int s28hx_t_post_sfdp_fixup(struct spi_nor *nor)
 	 */
 	params->rdsr_addr_nbytes = 4;
 
-	/* The 2 Gb parts duplicate info and advertise 4 dice instead of 2. */
-	if (params->size == SZ_256M)
-		params->n_dice = 2;
-
 	return cypress_nor_get_page_size(nor);
 }
 
@@ -733,12 +722,6 @@ static int s28hx_t_late_init(struct spi_nor *nor)
 {
 	struct spi_nor_flash_parameter *params = nor->params;
 
-	if (!params->n_dice || !params->vreg_offset) {
-		dev_err(nor->dev, "%s failed. The volatile register offset could not be retrieved from SFDP.\n",
-			__func__);
-		return -EOPNOTSUPP;
-	}
-
 	params->set_octal_dtr = cypress_nor_set_octal_dtr;
 	params->ready = cypress_nor_sr_ready_and_clear;
 	cypress_nor_ecc_init(nor);