I want to mount a 2nd SD Card (by using the SPI bus) to have a removable SD Card,
considering the main SD Card is the Boot device and not removable.
Howto go about this ?
Howto use the SPI bus to mount a 2nd SD Card on Luckfox Lyra board
In the mainline Linux kernel, there is an mmc_spi driver that enables direct control of SD cards via SPI. However, we currently have no relevant testing or usage experience with it. Note that the SPI controller on the RK3506 does not support multi-line modes, so the data rate may not be ideal.
Code: Select all
# ls /dev
block mmcblk1p1 rve tty30 tty6 vcsa6
char mmcblk1p2 shm tty31 tty60 vcsu
console mmcblk1p3 snd tty32 tty61 vcsu1
cpu_dma_latency mmcblk1p4 spidev0.0 tty33 tty62 vcsu2
disk mmcblk1p5 stderr tty34 tty63 vcsu3
fd mmcblk1p6 stdin tty35 tty7 vcsu4
full mmcblk1p7 stdout tty36 tty8 vcsu5
gpiochip0 mpi tty tty37 tty9 vcsu6
gpiochip1 mpp_service tty0 tty38 ttyFIQ0 video0
gpiochip2 null tty1 tty39 ttyS3 video1
gpiochip3 ptmx tty10 tty4 ttyS4 video10
hwrng pts tty11 tty40 ubi_ctrl video11
i2c-3 ram0 tty12 tty41 urandom video12
iio:device0 ram1 tty13 tty42 usb-ffs video13
initctl ram10 tty14 tty43 v4l video14
input ram11 tty15 tty44 v4l-subdev0 video15
iomux ram12 tty16 tty45 v4l-subdev1 video16
kmsg ram13 tty17 tty46 v4l-subdev2 video17
log ram14 tty18 tty47 vcodec video18
loop-control ram15 tty19 tty48 vcs video19
loop0 ram2 tty2 tty49 vcs1 video2
loop1 ram3 tty20 tty5 vcs2 video20
loop2 ram4 tty21 tty50 vcs3 video3
loop3 ram5 tty22 tty51 vcs4 video4
loop4 ram6 tty23 tty52 vcs5 video5
loop5 ram7 tty24 tty53 vcs6 video6
loop6 ram8 tty25 tty54 vcsa video7
loop7 ram9 tty26 tty55 vcsa1 video8
media0 random tty27 tty56 vcsa2 video9
media1 rga tty28 tty57 vcsa3 zero
mem rk_dma_heap tty29 tty58 vcsa4
mmcblk1 rknpu tty3 tty59 vcsa5
#
Neither /dev/mmcblk0 or /dev/mmcblk2 is created by the code below.
See below vvv
Last edited by jlsilicon on 2026-04-25 15:21, edited 4 times in total.
I tested the code below :
But, it Fails :
Why does it not create a MMC device ?
-
Modules Not present - now what do I do ???
Code: Select all
vi test_sdcardos.py
import os , sys
from periphery import SPI
# Open the SPI device :
spi = SPI("/dev/spidev0.0", 0, 1000000)
print("spi=" + str(spi))
sd_device_0 = "/dev/mmcblk0p1" # Typical SD node in Linux
sd_device_2 = "/dev/mmcblk2p1" #
mount_point = "/mnt/sdcard"
# Create mount :
if not os.path.exists(mount_point):
os.makedirs(mount_point)
# MOUNT : #
if ( os.system(f"mount {sd_device_0} {mount_point}") & 255 == 0 ) :
print(f"X ERR : Os.mount({sd_device_0} {mount_point})")
if ( os.system(f"mount {sd_device_2} {mount_point}") & 255 == 0 ) :
print(f"X ERR : Os.mount({sd_device_2} {mount_point})")
sys.exit(1)
# Test WRITE File : #
with open(f"{mount_point}/hello.txt", "w") as f:
f.write("Hello from Luckfox Ubuntu!")
print("SD Card Accessed Successfully")
python3 test_sdcardos.py
Code: Select all
python3 "test_sdcardos.py"
spi=SPI (device=/dev/spidev0.0, fd=3, mode=0, max_speed=1000000, bit_order=msb, bits_per_word=8, extra_flags=0x00000000)
m
mount: /mnt/sdcard: special device /dev/mmcblk0p1 does not exist.
X ERR : Os.mount(/dev/mmcblk0p1 /mnt/sdcard)
mount: /mnt/sdcard: special device /dev/mmcblk2p1 does not exist.
X ERR : Os.mount(/dev/mmcblk2p1 /mnt/sdcard)
-
Code: Select all
# sudo modprobe mmc_spi
modprobe: FATAL: Module mmc_spi not found in directory /lib/modules/5.10.160
# sudo modprobe mmc_spi
modprobe: FATAL: Module mmc_spi not found in directory /lib/modules/5.10.160
# sudo modprobe spi_dev
modprobe: FATAL: Module spi_dev not found in directory /lib/modules/5.10.160
# sudo depmod -a
depmod: ERROR: could not open directory /lib/modules/5.10.160: No such file or directory
depmod: FATAL: could not search modules: No such file or directory
#
Last edited by jlsilicon on 2026-04-25 16:09, edited 3 times in total.
Can you please give instructions on how to mount /dev/mmcblk0 for spi0.0 on Lyra board
see below
Last edited by jlsilicon on 2026-04-27 1:44, edited 2 times in total.
These chips really don't provide much to work.
Using LuckFox Pico Mini :
I tried DTS :
vi spi-bitbang-sd.dts
vi /boot/config.txt
dtoverlay=spi-bitbang-sd
Rebooted ...
dmesg | less
ls /dev
- only mmcblk1 mmcblk1p1 mmcblk1p2 mmcblk1p3 mmcblk1p4 mmcblk1p5 mmcblk1p6 mmcblk1p7
- no mmcblk0 or mmcblk2
Using LuckFox Pico Mini :
I tried DTS :
Code: Select all
SPI is enabled on :
SD CS -> G48
SD SCK -> G49
SD MOSI -> G50
SD MISO -> G51
Code: Select all
/dts-v1/;
/plugin/;
/ {
compatible = "brcm,bcm2835"; // Change for your specific board
fragment@0 {
target = <&gpio>;
__overlay__ {
bitbang_spi_pins: bitbang_spi_pins {
brcm,pins = <49 50 51 48>; // SCK, MOSI, MISO, CS
brcm,function = <1 1 0 1>; // OUT, OUT, IN, OUT
};
};
};
fragment@1 {
target = <&soc>;
__overlay__ {
/* Define the bitbang SPI bus */
spi_bitbang: spi-bitbang {
compatible = "spi-gpio";
#address-cells = <1>;
#size-cells = <0>;
pinctrl-names = "default";
pinctrl-0 = <&bitbang_spi_pins>;
sck-gpios = <&gpio 49 0>;
mosi-gpios = <&gpio 50 0>;
miso-gpios = <&gpio 51 0>;
cs-gpios = <&gpio 48 0>;
num-chipselects = <1>;
/* Define the SD Card on the bus */
sdcard: mmc@1 {
compatible = "mmc-spi-slot";
reg = <1>; // CS 1
spi-max-frequency = <1000000>; // Keep low for bitbang
voltage-ranges = <3300 3300>;
};
};
};
};
};
Code: Select all
dtc -@ -I dts -O dtb -o spi-bitbang-sd.dtbo spi-bitbang-sd.dts
mkdir /boot/overlays/
sudo cp spi-bitbang-sd.dtbo /boot/overlays/
dtoverlay=spi-bitbang-sd
Rebooted ...
dmesg | less
Code: Select all
[ 55.147440] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /spi@ff500000/status
[ 55.147488] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /spi@ff500000/pinctrl-0
[ 55.147505] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /spi@ff500000/spidev@0/status
property: /spi@ff500000/spidev@0/spi-max-frequency
[ 55.149225] rockchip-spi ff500000.spi: no high_speed pinctrl state
[ 55.154351] rockchip-spi ff500000.spi: chipselect 0 already in use
[ 55.154381] spi_master spi0: spi_device register error /spi@ff500000/fbtft@0
[ 55.154400] spi_master spi0: Failed to create SPI device for /spi@ff500000/fbtft@0
[ 55.154410] rockchip-spi ff500000.spi: probed, poll=0, rsd=0
[ 56.930116] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /i2c@ff460000/status
[ 56.930166] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /i2c@ff460000/clock-frequency
[ 56.930182] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /i2c@ff460000/pinctrl-0
[ 57.673690] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /serial@ff4e0000/pinctrl-0
[ 57.673736] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /serial@ff4e0000/status
[ 57.675000] ff4e0000.serial: ttyS4 at MMIO 0xff4e0000 (irq = 61, base_baud = 1500000) is a 16550A
[ 58.254364] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /serial@ff4d0000/pinctrl-0
[ 58.254414] OF: overlay: WARNING: memory leak will occur if overlay removed, property: /serial@ff4d0000/status
[ 58.255675] ff4d0000.serial: ttyS3 at MMIO 0xff4d0000 (irq = 62, base_baud = 1500000) is a 16550A- only mmcblk1 mmcblk1p1 mmcblk1p2 mmcblk1p3 mmcblk1p4 mmcblk1p5 mmcblk1p6 mmcblk1p7
- no mmcblk0 or mmcblk2
Last edited by jlsilicon on 2026-04-27 1:51, edited 1 time in total.
As mentioned in the previous post, we have no experience testing or using the mmc_spi driver, and this is not covered under technical support（https://wiki.luckfox.com/intro）. Therefore, we are unable to address any issues you may encounter during its use. Based on the information you've provided, it appears that the CONFIG_MMC_SPI option is not enabled in the kernel, and the SPI node in the device tree also requires modification. Attempting to add an MMC device through user-space operations is not feasible.
Also, please note that the dtb overlay implementation on the RK3506 differs significantly from that on the Raspberry Pi. The dtb overlay you provided will certainly not work on the Luckfox Lyra. We recommend manually modifying the device tree using the SDK, as compiling it will provide more detailed information for identifying device tree configuration issues. Lastly, we suggest that you first familiarize yourself with the SDK development approach for the Luckfox Lyra by referring to the Wiki. Much of the information you've provided so far follows Raspberry Pi practices, which are not applicable to the Luckfox Lyra.
Also, please note that the dtb overlay implementation on the RK3506 differs significantly from that on the Raspberry Pi. The dtb overlay you provided will certainly not work on the Luckfox Lyra. We recommend manually modifying the device tree using the SDK, as compiling it will provide more detailed information for identifying device tree configuration issues. Lastly, we suggest that you first familiarize yourself with the SDK development approach for the Luckfox Lyra by referring to the Wiki. Much of the information you've provided so far follows Raspberry Pi practices, which are not applicable to the Luckfox Lyra.
Pretty sad lack of support here for your chips.
* adafruit-circuitpython-sdcard - does Not work.
* Spi-fat-fuse - does not work.
* dts file format for spi - does Not work.
What does work on these boards ???
* adafruit-circuitpython-sdcard - does Not work.
* Spi-fat-fuse - does not work.
* dts file format for spi - does Not work.
What does work on these boards ???
The solutions you mentioned are all built for the Raspberry Pi ecosystem. Currently, no other ecosystem in the world can match the Raspberry Pi's level of completeness. The development approach of the Luckfox Lyra is fundamentally different from that of the Raspberry Pi, which means it cannot take advantage of the Raspberry Pi software ecosystem. If you're not comfortable with or can't fully embrace this kind of native Linux development style, I would suggest sticking with a Raspberry Pi to accomplish what you need.