SD CARD host controller

[Stone]

I am programming Genesys2 with Vivado/Vitis 2020.2 and could write and read Quad-SPI using AxI_QUAD_SPI LogiCore and Xilinx library spi_v4_7 ( including xspi.c ). I could use MicroBlaze, HDMI (source and sink), VDMA and MIG. However I could not find a way to wirte and read the SD CARD on the board. I tried xilffs but the functions such as f_mout, f_open and f_read were rejected by the Vitis compiler. I had no problem to read/write SD-CARD with Zybo, Zybo-Zu and Zedboard.  I read the article "SDSPI controller specification" introduced by Gisselquest Technology in this forum.

Q1) I would like to know whether this software (SDSPI) supports the functions such as  f_mout, f_open and f_read to read and write files by file name.

Q2) Is there any other way to use SD CARD host controller for Genesys2?

Q3) SPI seems not supporting read/write by file name. Is there any way to read/write files by file name as SD-CARD reader?  I wish to store bitmap data in SPI. 

Regards

Fred

 

[JColvin]

Hi @Stone,

I'm not able to directly comment what functions the SDSPI made by @D@n supports, though documentation on it is available on his GitHub page for it: https://github.com/ZipCPU/sdspi.

As an off-hand guess, I'm guessing the reading of the SD card went more smoothly on the Zynq based devices since the ARM core has a designated SD card "interface".

I haven't personally tested it, but xilffs should be compatible with 2020.2, or at least Xilinx has a 2020.2 changelog entry for it, https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18841771/xilffs and an existing example that uses f_mount, f_open, and f_read, https://github.com/Xilinx/embeddedsw/blob/master/lib/sw_services/xilffs/examples/xilffs_polled_example.c.

Thanks,
JColvin

[D@n]

@Stone,

The SDSPI controller is supported by the FATFS library.  The necessary glue functions can be found in the software directory.  The f_mount, f_open, and f_read functions are part of the FATFS library, so yes, they are supported.

Dan