[PATCH] doc: board: nxp: Add remoteproc guide

[Peng Fan]

Add guide on how to use the Remote Processors on i.MX8M and i.MX93.

Update MAINTAINERS to include doc/board/nxp.

Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 MAINTAINERS             |  1 +
 doc/board/nxp/index.rst |  1 +
 doc/board/nxp/rproc.rst | 69 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 671903605d17a78b88d83ddb7e01b78115b553e7..b30ebdabefa087995fa9147f11d862fe0a12b75d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -317,6 +317,7 @@ F:	arch/arm/include/asm/mach-imx/
 F:	board/freescale/*mx*/
 F:	board/freescale/common/
 F:	common/spl/spl_imx_container.c
+F:	doc/board/nxp/
 F:	doc/imx/
 F:	drivers/mailbox/imx-mailbox.c
 F:	drivers/serial/serial_mxc.c
diff --git a/doc/board/nxp/index.rst b/doc/board/nxp/index.rst
index 670501164b5c11f64dc1dab03b6f90e2fba0163d..7b881961b65d4b481b018761cdedb7efb4d208c7 100644
--- a/doc/board/nxp/index.rst
+++ b/doc/board/nxp/index.rst
@@ -26,4 +26,5 @@ NXP Semiconductors
    mx6sabresd
    mx6ul_14x14_evk
    mx6ullevk
+   rproc
    psb
diff --git a/doc/board/nxp/rproc.rst b/doc/board/nxp/rproc.rst
new file mode 100644
index 0000000000000000000000000000000000000000..b023c1fadf6253438158b46a9ca1cc9a4e3dd757
--- /dev/null
+++ b/doc/board/nxp/rproc.rst
@@ -0,0 +1,69 @@
+.. SPDX-License-Identifier: GPL-2.0+
+   Copyright 2025 NXP
+   Written by Peng Fan <peng.fan at nxp.com>
+
+i.MX remoteproc usage guide
+===========================
+
+Introduction
+------------
+
+This guide is for giving user how to use the Remote Processors found on
+various i.MX Chips. The term remote processor is indicating the Cortex-M
+[4,7,33] cores inside i.MX family.
+
+i.MX8MM-EVK
+-----------
+
+Steps to start the Cortex-M4 core
+
+    load mmc 2:2 0x90000000 /lib/firmware/imx8mm_m4_TCM_rpmsg_lite_str_echo_rtos.elf
+
+    rproc load 0 0x90000000 ${filesize}
+
+    rproc start 0
+
+i.MX8MN-EVK
+-----------
+
+Steps to start the Cortex-M7 core
+
+    load mmc 2:2 0x90000000 /lib/firmware/imx8mn_m7_TCM_rpmsg_lite_str_echo_rtos.elf
+
+    rproc load 0 0x90000000 ${filesize}
+
+    rproc start 0
+
+i.MX8MQ-EVK
+-----------
+
+Steps to start the Cortex-M4 core
+
+    load mmc 0:2 0x90000000 /lib/firmware/imx8mq_m4_TCM_rpmsg_lite_str_echo_rtos.elf
+
+    rproc load 0 0x90000000 ${filesize}
+
+    rproc start 0
+
+i.MX8MP-EVK
+-----------
+
+Steps to start the Cortex-M7 core
+
+    load mmc 2:2 0x90000000 /lib/firmware/imx8mp_m7_TCM_rpmsg_lite_str_echo_rtos.elf
+
+    rproc load 0 0x90000000 ${filesize}
+
+    rproc start 0
+
+i.MX93-FRDM/QSB/EVK
+-------------------
+
+Steps to start the Cortex-M33 core, need to choose the correct file for
+corresponding board.
+
+    load mmc 0:2 0x90000000 /lib/firmware/imx93-11x11-evk_m33_TCM_rpmsg_lite_str_echo_rtos.elf
+
+    rproc load 0 0x90000000 ${filesize}
+
+    rproc start 0

---
base-commit: a58089ad2e41e88f81360f0e99bfd0715aceb556
change-id: 20251020-rproc-doc-3e0f5df18c48

Best regards,
-- 
Peng Fan <peng.fan at nxp.com>