spi: cadence-qspi: Add a small delay before indirect writes

Once the start bit is toggled it takes a small amount of time before it
is internally synchronized. This means we can't start writing during
that part. So add a small delay to allow the bit to be synchronized.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c
index b051f462ed..92e57730bd 100644
--- a/drivers/spi/cadence_qspi_apb.c
+++ b/drivers/spi/cadence_qspi_apb.c
@@ -730,6 +730,12 @@ cadence_qspi_apb_indirect_write_execute(struct cadence_spi_plat *plat,
 	writel(CQSPI_REG_INDIRECTWR_START,
 	       plat->regbase + CQSPI_REG_INDIRECTWR);
 
+	/*
+	 * Some delay is required for the above bit to be internally
+	 * synchronized by the QSPI module.
+	 */
+	ndelay(plat->wr_delay);
+
 	while (remaining > 0) {
 		write_bytes = remaining > page_size ? page_size : remaining;
 		writesl(plat->ahbbase, bb_txbuf, write_bytes >> 2);