mtd: spi-nor: move all micron-st specifics into micron-st.c

The flag status register is only available on micron flashes. Move all
the functions around that into the micron module.

This is almost a mechanical move except for the spi_nor_fsr_ready()
which now also checks the normal status register. Previously, this was
done in spi_nor_ready().

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Tested-by: Pratyush Yadav <p.yadav@ti.com> # on mt35xu512aba, s28hs512t
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-25-michael@walle.cc

1 files changed, 134 insertions, 0 deletions

diff --git a/drivers/mtd/spi-nor/micron-st.c b/drivers/mtd/spi-nor/micron-st.c
index 7a68f2ad3ea1..e580830ed70f 100644
--- a/drivers/mtd/spi-nor/micron-st.c
+++ b/drivers/mtd/spi-nor/micron-st.c
@@ -8,6 +8,8 @@
 
 #include "core.h"
 
+#define SPINOR_OP_RDFSR		0x70	/* Read flag status register */
+#define SPINOR_OP_CLFSR		0x50	/* Clear flag status register */
 #define SPINOR_OP_MT_DTR_RD	0xfd	/* Fast Read opcode in DTR mode */
 #define SPINOR_OP_MT_RD_ANY_REG	0x85	/* Read volatile register */
 #define SPINOR_OP_MT_WR_ANY_REG	0x81	/* Write volatile register */
@@ -17,6 +19,12 @@
 #define SPINOR_MT_OCT_DTR	0xe7	/* Enable Octal DTR. */
 #define SPINOR_MT_EXSPI		0xff	/* Enable Extended SPI (default) */
 
+/* Flag Status Register bits */
+#define FSR_READY		BIT(7)	/* Device status, 0 = Busy, 1 = Ready */
+#define FSR_E_ERR		BIT(5)	/* Erase operation status */
+#define FSR_P_ERR		BIT(4)	/* Program operation status */
+#define FSR_PT_ERR		BIT(1)	/* Protection error bit */
+
 static int micron_st_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
 {
 	struct spi_mem_op op;
@@ -273,6 +281,125 @@ static int micron_st_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 	return spi_nor_write_disable(nor);
 }
 
+/**
+ * spi_nor_read_fsr() - Read the Flag Status Register.
+ * @nor:	pointer to 'struct spi_nor'
+ * @fsr:	pointer to a DMA-able buffer where the value of the
+ *              Flag Status Register will be written. Should be at least 2
+ *              bytes.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_read_fsr(struct spi_nor *nor, u8 *fsr)
+{
+	int ret;
+
+	if (nor->spimem) {
+		struct spi_mem_op op =
+			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDFSR, 0),
+				   SPI_MEM_OP_NO_ADDR,
+				   SPI_MEM_OP_NO_DUMMY,
+				   SPI_MEM_OP_DATA_IN(1, fsr, 0));
+
+		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
+			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
+			op.dummy.nbytes = nor->params->rdsr_dummy;
+			/*
+			 * We don't want to read only one byte in DTR mode. So,
+			 * read 2 and then discard the second byte.
+			 */
+			op.data.nbytes = 2;
+		}
+
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
+		ret = spi_mem_exec_op(nor->spimem, &op);
+	} else {
+		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDFSR, fsr,
+						      1);
+	}
+
+	if (ret)
+		dev_dbg(nor->dev, "error %d reading FSR\n", ret);
+
+	return ret;
+}
+
+/**
+ * spi_nor_clear_fsr() - Clear the Flag Status Register.
+ * @nor:	pointer to 'struct spi_nor'.
+ */
+static void spi_nor_clear_fsr(struct spi_nor *nor)
+{
+	int ret;
+
+	if (nor->spimem) {
+		struct spi_mem_op op =
+			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLFSR, 0),
+				   SPI_MEM_OP_NO_ADDR,
+				   SPI_MEM_OP_NO_DUMMY,
+				   SPI_MEM_OP_NO_DATA);
+
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
+		ret = spi_mem_exec_op(nor->spimem, &op);
+	} else {
+		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_CLFSR,
+						       NULL, 0);
+	}
+
+	if (ret)
+		dev_dbg(nor->dev, "error %d clearing FSR\n", ret);
+}
+
+/**
+ * spi_nor_fsr_ready() - Query the Status Register as well as the Flag Status
+ * Register to see if the flash is ready for new commands. If there are any
+ * errors in the FSR clear them.
+ * @nor:	pointer to 'struct spi_nor'.
+ *
+ * Return: 1 if ready, 0 if not ready, -errno on errors.
+ */
+static int spi_nor_fsr_ready(struct spi_nor *nor)
+{
+	int sr_ready, ret;
+
+	sr_ready = spi_nor_sr_ready(nor);
+	if (sr_ready < 0)
+		return sr_ready;
+
+	ret = spi_nor_read_fsr(nor, nor->bouncebuf);
+	if (ret)
+		return ret;
+
+	if (nor->bouncebuf[0] & (FSR_E_ERR | FSR_P_ERR)) {
+		if (nor->bouncebuf[0] & FSR_E_ERR)
+			dev_err(nor->dev, "Erase operation failed.\n");
+		else
+			dev_err(nor->dev, "Program operation failed.\n");
+
+		if (nor->bouncebuf[0] & FSR_PT_ERR)
+			dev_err(nor->dev,
+				"Attempted to modify a protected sector.\n");
+
+		spi_nor_clear_fsr(nor);
+
+		/*
+		 * WEL bit remains set to one when an erase or page program
+		 * error occurs. Issue a Write Disable command to protect
+		 * against inadvertent writes that can possibly corrupt the
+		 * contents of the memory.
+		 */
+		ret = spi_nor_write_disable(nor);
+		if (ret)
+			return ret;
+
+		return -EIO;
+	}
+
+	return sr_ready && !!(nor->bouncebuf[0] & FSR_READY);
+}
+
 static void micron_st_nor_default_init(struct spi_nor *nor)
 {
 	nor->flags |= SNOR_F_HAS_LOCK;
@@ -281,8 +408,15 @@ static void micron_st_nor_default_init(struct spi_nor *nor)
 	nor->params->set_4byte_addr_mode = micron_st_nor_set_4byte_addr_mode;
 }
 
+static void micron_st_nor_late_init(struct spi_nor *nor)
+{
+	if (nor->flags & SNOR_F_USE_FSR)
+		nor->params->ready = spi_nor_fsr_ready;
+}
+
 static const struct spi_nor_fixups micron_st_nor_fixups = {
 	.default_init = micron_st_nor_default_init,
+	.late_init = micron_st_nor_late_init,
 };
 
 const struct spi_nor_manufacturer spi_nor_micron = {