[PATCH 2/5] spi: spi-nxp-fspi: Add the DDR LUT command support

From: Haibo Chen
Date: Tue Sep 16 2025 - 03:57:43 EST


For DTR mode, flexspi need to use DDR LUT command, flexspi will switch
to DDR mode when detect the DDR LUT command.

Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
---
drivers/spi/spi-nxp-fspi.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-nxp-fspi.c b/drivers/spi/spi-nxp-fspi.c
index a1c9ad03379682dc1fc2908fbd83e1ae8e91588f..6b3e6b427ba84734a2359a964635a8f05cd146fd 100644
--- a/drivers/spi/spi-nxp-fspi.c
+++ b/drivers/spi/spi-nxp-fspi.c
@@ -559,12 +559,22 @@ static void nxp_fspi_prepare_lut(struct nxp_fspi *f,
u32 target_lut_reg;

/* cmd */
- lutval[0] |= LUT_DEF(0, LUT_CMD, LUT_PAD(op->cmd.buswidth),
- op->cmd.opcode);
+ if (op->cmd.dtr) {
+ lutval[0] |= LUT_DEF(0, LUT_CMD_DDR, LUT_PAD(op->cmd.buswidth),
+ op->cmd.opcode >> 8);
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_CMD_DDR,
+ LUT_PAD(op->cmd.buswidth),
+ op->cmd.opcode & 0xFF);
+ lutidx++;
+ } else {
+ lutval[0] |= LUT_DEF(0, LUT_CMD, LUT_PAD(op->cmd.buswidth),
+ op->cmd.opcode);
+ }

/* addr bytes */
if (op->addr.nbytes) {
- lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_ADDR,
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, op->addr.dtr ?
+ LUT_ADDR_DDR : LUT_ADDR,
LUT_PAD(op->addr.buswidth),
op->addr.nbytes * 8);
lutidx++;
@@ -572,7 +582,8 @@ static void nxp_fspi_prepare_lut(struct nxp_fspi *f,

/* dummy bytes, if needed */
if (op->dummy.nbytes) {
- lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_DUMMY,
+ lutval[lutidx / 2] |= LUT_DEF(lutidx, op->dummy.dtr ?
+ LUT_DUMMY_DDR : LUT_DUMMY,
/*
* Due to FlexSPI controller limitation number of PAD for dummy
* buswidth needs to be programmed as equal to data buswidth.
@@ -587,7 +598,8 @@ static void nxp_fspi_prepare_lut(struct nxp_fspi *f,
if (op->data.nbytes) {
lutval[lutidx / 2] |= LUT_DEF(lutidx,
op->data.dir == SPI_MEM_DATA_IN ?
- LUT_NXP_READ : LUT_NXP_WRITE,
+ (op->data.dtr ? LUT_READ_DDR : LUT_NXP_READ) :
+ (op->data.dtr ? LUT_WRITE_DDR : LUT_NXP_WRITE),
LUT_PAD(op->data.buswidth),
0);
lutidx++;

--
2.34.1