Enabling SD Interface on P2020 Reference Design Board

[#1]

To enable SD interface in SPI boot on P2020RDB: 1. Perform the following updates in u-boot a) Modify pmuxcr to enable SD bus in case of SPI boot b) Update the corresponding static mux implementation in u-boot 2. Perform the following updates in Linux a) Disable IFC from device tree and kernel defconfig

The patch details to enable SD interface are given below. A zip file, AN4336SW.zip, containing the patches for u-boot and Linux accompanies this application note. The file can be downloaded from [1].

U-Boot

•   Extract the u-boot code from the QorIQ SDK 1.0.1 iso
•   Apply the patch, u-boot-P2020rdb-enabling-sd-in-spi-boot.patch
•   Compile the u-boot using "make" command for SPI Flash

   make ARCH=powerpc   CROSS_COMPILE=/opt/freescale/usr/local/gcc-4.5.55-eglibc-2.11.55/powerpc-linux-gnu/bin/powerpc-linux-gnu- P2020RDB_SPIFLASH

•   Use the boot_format utility to generate the spiimage. For more information, see SDK manual.
•   Update the SPI Flash with the above built spiimage

Linux

• Extract the Linux source code from QorIQ SDK 1.0.1 iso
• Apply the patch, linux-P2020rdb-enabling-sd-in-spi-boot.patch
• Compile Linux using make command

 #make ARCH=powerpc  CROSS_COMPILE=/opt/freescale/usr/local/gcc-4.5.55-eglibc-2.11.55/powerpc-linux-gnu/bin/powerpc-linux-gnuarch/  powerpc/configs/qoriq_sdk_nonsmp_defconfig  #make ARCH=powerpc  CROSS_COMPILE=/opt/freescale/usr/local/gcc-4.5.55-eglibc-2.11.55/powerpc-linux-gnu/bin/powerpc-linux-gnu-

• Compile the dts

 ./sripts/dtc/dtc -f -I dts -O dtb -R 8 -S 0x3000  arc/powerpc/boot/dts/P2020rdb.dts.dts > P2020rdb.dtb.dtb

• With the updated SPI bootloader, Linux uImage and P2020rdb.dtb, the user must be able to enable SD interface on P2020RDB.

NOTE

• The above-mentioned changes must be done only when the user specifically requires the SD interface using SPI boot.
• For all other boot methods, these patches must not be used.