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mapping /dev/mem failed - Raspberry PI 5 64-Bit - Waveshare 3.5" B Rev 2.0 GPIO-Display #329

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@bassemolufda
$ cat /proc/cmdline
reboot=w coherent_pool=1M 8250.nr_uarts=1 pci=pcie_bus_safe snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 clk_ignore_unused  smsc95xx.macaddr=2C:CF:67:3D:32:C3 vc_mem.mem_base=0x3fc00000 vc_mem.mem_size=0x40000000  console=ttyAMA10,115200 console=tty1 root=PARTUUID=bee7140b-02 rootfstype=ext4 fsck.repair=yes rootwait cfg80211.ieee80211_regdom=DE fbcon=map:10 iomem=relaxed
$ lscpu
Architecture:             aarch64
CPU op-mode(s):         32-bit, 64-bit
Byte Order:             Little Endian
CPU(s):                   4
On-line CPU(s) list:    0-3
Vendor ID:                ARM
Model name:             Cortex-A76
Model:                1
Thread(s) per core:   1
Core(s) per cluster:  4
$ uname -a
Linux mediacenter 6.6.28+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.6.28-1+rpt1 (2024-04-22) aarch64 GNU/Linux

$ cat /boot/firmware/config.txt
dtparam=spi=on
dtoverlay=vc4-fkms-v3d
max_framebuffers=2
sdtv_aspect=3
#dtoverlay=watterott-display,drm
#dtoverlay=waveshare35b-v2,drm,rotate=90,invertx=1,swapxy=1
hdmi_force_hotplug=1
max_usb_current=1

For Kodi-Standalone it must be "dtoverlay=vc4-kms-v3d" or "dtoverlay=vc4-fkms-v3d"
otherwise Kodi will not be displayed on the TV. The "legacy firmware" and "FKMS" display modes used in earlier versions of Raspberry Pi OS are no longer supported; KMS (Kernel Mode Setting) is now used instead.

$ cmake -DSPI_BUS_CLOCK_DIVISOR=40 -DWAVESHARE35B_ILI9486=ON -DUSE_DMA_TRANSFERS=OFF -DARMV8A=ON -DAARCH64=YES -DSTATISTICS=0 ..

$ sudo ./fbcp-ili9341 
bcm_host_get_peripheral_address: 0x10, bcm_host_get_peripheral_size: 2080374784, bcm_host_get_sdram_address: 0xc0000000
**mapping /dev/mem failed**

I get ever mapping /dev/mem failed on a Raspberry PI 5 with Raspbian Bookworm Lite 64 Bit Aarch64.
Maybe someone has a recommendation for a 3.5" display that works? The 3.5" display should show the image content from the HDMI output.

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