spi: spi-nxp-fspi: Add the DDR LUT command support

JIRA: https://issues.redhat.com/browse/RHEL-104570

commit 3c1000e
Author: Haibo Chen <haibo.chen@nxp.com>
Date:   Wed Sep 17 15:27:08 2025 +0800

    spi: spi-nxp-fspi: Add the DDR LUT command support

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

    Reviewed-by: Frank Li <Frank.Li@nxp.com>
    Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
    Link: https://patch.msgid.link/20250917-flexspi-ddr-v2-3-bb9fe2a01889@nxp.com
    Signed-off-by: Mark Brown <broonie@kernel.org>

Signed-off-by: Mattijs Korpershoek <mkorpershoek@redhat.com>

Author: makohoek

drivers/spi/spi-nxp-fspi.c

@@ -559,20 +559,29 @@ 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++;
 	}
 
 	/* 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 +596,8 @@ 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++;