imx: imxrt1050-evk: Add documentation for SPI boot

Add documentation for SPI boot.

Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>

diff --git a/doc/board/nxp/imxrt1050-evk.rst b/doc/board/nxp/imxrt1050-evk.rst
index c1fb48f0cdd9cd1915534c989377ef756a4ef407..e0cafe1035d0dc3d53e5b9760cef126bd170fb52 100644 (file)
--- a/doc/board/nxp/imxrt1050-evk.rst
+++ b/doc/board/nxp/imxrt1050-evk.rst
@@ -39,3 +39,33 @@ switch label numbers reference).
   The USB console connector is the one close the ethernet connector
 
 - Insert the micro SD card in the board, power it up and U-Boot messages should come up.
+
+
+How to use U-Boot with SPI flash on NXP i.MXRT1050 EVK
+------------------------------------------------------
+
+- Build U-Boot for i.MXRT1050 EVK:
+
+.. code-block:: bash
+
+   $ make mrproper
+   $ make imxrt1050-evk_fspi_defconfig
+   $ make
+
+This will generate SPL, uboot.img, fspi_header.bin, and the final image (flash.bin).
+
+To boot from SPI flash on other boards, you may need to change the flash header config,
+which is specific to your flash chip, in Kconfig.
+The flash config is 4K in size and is documented on page 217 of the imxrt1050 RM.
+The default flash chip on the i.MXRT1050 EVK is the S26KS512SDPBHI02 HYPERFLASH.
+
+- Jumper settings::
+
+   SW7: 0 1 1 0
+
+where 0 means bottom position and 1 means top position (from the
+switch label numbers reference).
+
+- Connect the USB cable between the EVK and the PC for the console.
+
+- Use either JTAG or SWD to write `flash.bin` to the NOR. I used Mcuexpresso IDE's GUI flash tool.