The reading speed of SD card is too slow, only 1.4mb/s. How to improve the reading speed of SD card

Autonomous Machines Jetson & Embedded Systems Jetson Nano
1

The reading and writing speed of SD card is too slow. We tested that the reading and writing speed of SD card is only about 1.4mb/s.
This is our dtsi:
提问1
We tried to modify dtsi. When we increased the limited frequency range of max-clk-limit, the reading speed of SD card did not improve. When we deleted option max-clk-limit, we could not read SD card.
The frequency of SDIO clock pin measured by oscilloscope is only 3.1mhz.

提问2
提问2678×505 49.7 KB

  1. What ways can I improve the reading and writing speed of SD card.
  2. Does the frequency of the pin affect the reading speed of the SD card? If so, how to modify the frequency of the pin.
3

What is the release version you are using? I remember max-clk-limit has already been removed from Nano dts for quite long.

The device tree is also wrong. Lacking of cd-gpio and vmmc-supply. That makes you not able to remove the max-clk-limit.

For old release <=32.2. Below thread includes the need.

And this thread is for rel-32.5.1 that was just done last week.