The source code I use comes from l4t 32.5.1 public sources (Jetson nano)
When I modify (/ hardware / NVIDIA / platform / t210 / porg / kernel DTS / tegra210-porg-p3448-common.dtsi), as shown in the following figure, the SD card cannot be read out.
When I modify (/ hardware / NVIDIA / platform / t210 / porg / kernel DTS / tegra210-porg-p3448-common.dtsi) as shown in the figure below, the SD card can be read out, but the reading and writing speed is very slow.
I’ve found many ways to modify it in the forum. It seems that it doesn’t work. What’s the solution
I have disabled other occupied GPIO. Now there are some new problems. I can see the SD card through the instruction lsblk, but I can’t see the SD card using the ‘df -h’ instruction. Then dmesg also prints some error messages.
After modifying the above three files, dmesg shows that GPIO reuse exists, so I use grep - r 'TEGRA_GPIO(Z, 2) 'instruction finds and removes files using the GPIO.
1.nvidia/platform/t210/porg/kernel-dts/porg-platforms/tegra210-porg-pwm-fan.dtsi
And dmesg also printed some errors. I have tried many modification methods and can’t solve them. I hope to get some technical support dmesg4.5.1.docx (34.2 KB)
Last week, I checked the hardware circuit. After changing the hardware circuit, I can read the SD card, but the reading speed is still very slow. I deleted the limited frequency (max-clk-limit) according to the modification suggestions of the forum, but the reading speed of the SD card has not improved much, and the clock frequency is only 25MHz by default, as shown in the figure below. How can I increase this frequency to improve the reading speed of the SD card?