Design Note TE0724-04 QSPI Flash

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Products Affected

This Design Note affects SoM TE0724 revision 04 with 512Mbit ISSI Flash:

Description

Affected products are equipped with ISSI 512Mbit flash (IS25LP512M-RHLE).

This flash is listed as 'Supported Flash Memory Devices for Zynq-7000 Device Configuration' in Xilinx UG908 (since version 2019.1), but there are problems with reboot after petalinux was started:

For Petalinux Kernels after version 2019.1 the Flag "SPI_NOR_HAS_LOCK" has to be removed from the model "is25lp512m" in the device-driver to fix this behaviour.

Exemplary for 2023.2 version the line is marked here: https://github.com/Xilinx/linux-xlnx/blob/xilinx-v2023.2/drivers/mtd/spi-nor/issi.c#L231

There is still no official patch for any known petalinux version (as the time of writing 2024.2 is the current release). 

Notice that you device-tree settings have also to be correct regarding bus-width properties, otherwise a similar error than described in this note will occur. Please consult our reference design for more information.

We have not encountered any problems in bare metal applications.

Therefore if you cannot change your software according to above recomendations you can use modules with 256Mbit Spansion flash S25FL256SAGBHI20 as listed below. With exception of the flash, the modules are identical. Furthermore the Spansion flash is the same as on revision 03 of TE0724.