[PATCH v4 16/16] mtd: spi-nor: run PHY tuning after init and update dirmap frequency

[Santhosh Kumar K]

Run PHY tuning in spi_nor_probe() before creating dirmaps so the
validated frequency is available at dirmap construction time.

Store the configured read op template in nor->max_read_op and pass it
to spi_mem_execute_tuning(). On success the controller sets
max_read_op.max_freq to the calibrated rate. spi_nor_spimem_get_read_op()
propagates nor->max_read_op.max_freq into every op it returns, so the
validated frequency flows automatically into the dirmap template and into
regular read ops.

Tuning failure is non-fatal; the device operates at the conservative
base rate.

Signed-off-by: Santhosh Kumar K <s-k6@xxxxxx>
---
 drivers/mtd/spi-nor/core.c  | 14 ++++++++++++++
 include/linux/mtd/spi-nor.h |  3 +++
 2 files changed, 17 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index b683c077a233..a2a2cf3d3603 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -216,6 +216,9 @@ static struct spi_mem_op spi_nor_spimem_get_read_op(struct spi_nor *nor)
 	if (spi_nor_protocol_is_dtr(nor->read_proto))
 		op.dummy.nbytes *= 2;
 
+	/* Propagate the validated frequency; zero before tuning. */
+	op.max_freq = nor->max_read_op.max_freq;
+
 	return op;
 }
 
@@ -3843,6 +3846,17 @@ static int spi_nor_probe(struct spi_mem *spimem)
 			return -ENOMEM;
 	}
 
+	/*
+	 * Populate the persistent template and run PHY tuning before dirmap
+	 * creation so the validated frequency feeds into the dirmap op.
+	 * Tuning failure is non-fatal; the device operates at base speed.
+	 */
+	nor->max_read_op = spi_nor_spimem_get_read_op(nor);
+
+	ret = spi_mem_execute_tuning(spimem, &nor->max_read_op, NULL);
+	if (ret && ret != -EOPNOTSUPP)
+		dev_warn(dev, "Failed to execute PHY tuning: %d\n", ret);
+
 	ret = spi_nor_create_read_dirmap(nor);
 	if (ret)
 		return ret;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 4b92494827b1..ab498a50f15f 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -422,6 +422,9 @@ struct spi_nor {
 		struct spi_mem_dirmap_desc *wdesc;
 	} dirmap;
 
+	/* Persistent op template updated by execute_tuning with validated speed. */
+	struct spi_mem_op max_read_op;
+
 	void *priv;
 };
 
-- 
2.34.1