I'm building a custom linux with buildroot in combination with U-Boot on compute module 3(+). I can boot with and without U-Boot. But if the kernel is booted through U-Boot there is no I2C bus available.
If the kernel is booted directly (kernel=Image) everything is working like intended.
In both cases i2c_dev module is loaded and I can't see any big differences.
I added my config.txt. Here only the kernel= line changes accordingly.
Furthermore I have posted my boot script. I use a first stage bootscript to source the actual boot.scr as part of a fallback system. Shouldn't be make a difference though...
Lastly I recorded the boot process in both cases and constructed a diff. I can't make out any meaningful differences.
At the very end It is visible how i2c-detect -l yields for the direct boot
i2c-1 i2c bcm2835 (i2c@7e804000) I2C adapter
But nothing for the U-Boot boot.
buildroot: 2022.02.6
Kernel: 5.10.92
U-Boot: 2022.01
config.txt:
kernel=u-boot.bin
#kernel=Image
arm_64bit=1
dtparam=spi=on
dtparam=i2c_arm=on
dtoverlay=spi0-1cs,cs0_pin=43
enable_uart=1
uart_2ndstage=1
dtdebug=1
boot.scr:
if test "${boot_kernel}" = 2; then
echo "###Loading factory kernel###"
load mmc 0:2 ${kernel_addr_r} images/factory/Image;
load mmc 0:2 ${fdt_addr} images/factory/bcm2710-rpi-cm3.dtb;
elif test "${boot_kernel}" = 1; then
echo "###Loading previous kernel###"
load mmc 0:2 ${kernel_addr_r} images/previous/Image;
load mmc 0:2 ${fdt_addr} images/previous/bcm2710-rpi-cm3.dtb;
else
echo "###Loading current kernel###"
load mmc 0:2 ${kernel_addr_r} images/latest/Image;
load mmc 0:2 ${fdt_addr} images/latest/bcm2710-rpi-cm3.dtb;
fi
setenv bootargs 'coherent_pool=1M snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2708_fb.fbswap=1 smsc95xx.macaddr=B8:27:EB:81:BF:03 vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait'
#setenv bootargs console=ttyAMA0,115200 printk.devkmsg=on usbcore.autosuspend=-1 fsck.mode=force fsck.repair=yes
env save
booti ${kernel_addr_r} - ${fdt_addr}
first_boot.scr
[...]
if test "${isa_boot_count}" > 4; then
echo "###Loading factory kernel bootscript###"
setenv isa_boot_kernel 2;
load mmc 0:2 ${scriptaddr} images/factory/boot.scr;
source ${scriptaddr}
[...]
--- out_Image 2022-10-31 09:20:35.482122089 +0100
+++ out_uboot 2022-10-31 09:39:24.338868824 +0100
@@ -118,18 +118,78 @@
Unknown dtparam 'core_freq' - ignored
gpioman: gpioman_get_pin_num: pin WL_ON not defined
dtdebug: delete_node(/hat)
-brfs: File read: /mfs/sd/Image
-Loading 'Image' to 0x80000 size 0x3e04a00
-Kernel relocated to 0x200000
+brfs: File read: /mfs/sd/u-boot.bin
+Loading 'u-boot.bin' to 0x80000 size 0x7ce20
Device tree loaded to 0x2eff8a00 (size 0x75f9)
uart: Set PL011 baud rate to 103448.300000 Hz
uart: Baud rate change done...
uart: Baud rate change done...
gpioman: gpioman_get_pin_num: pin SDCARD_CONTROL_POWER not defined
+
+
+U-Boot 2022.01 (Oct 19 2022 - 14:23:33 +0200)
+
+Model: Raspberry Pi Compute Module 3 Rev 1.0
+DRAM: 948 MiB
+RPI Compute Module 3 (0xa220a0)
+MMC: mmc@7e202000: 0
+Loading Environment from FAT... WARNING at drivers/mmc/bcm2835_sdhost.c:414/bcm2835_send_command()!
+WARNING at drivers/mmc/bcm2835_sdhost.c:414/bcm2835_send_command()!
+OK
+In: serial
+Out: vidconsole
+Err: vidconsole
+Model: Raspberry Pi Compute Module 3 Rev 1.0
+Hit any key to stop autoboot: 2 1 0
+1366 bytes read in 1 ms (1.3 MiB/s)
+## Executing script at 02400000
+Loading env
+Loading Environment from FAT... OK
+isa_boot_count=None
+Boot counter variable found
+isa_boot_kernel=2
+Kernel type variable found
+Increasing boot count
+Saving Environment to FAT... OK
+###Loading current kernel bootscript###
+Failed to load 'isatech-images/latest/boot.scr'
+## Executing script at 02400000
+Loading env
+Loading Environment from FAT... OK
+isa_boot_count=1
+Boot counter variable found
+isa_boot_kernel=2
+Kernel type variable found
+Increasing boot count
+Saving Environment to FAT... OK
+###Loading current kernel bootscript###
+Failed to load 'isatech-images/latest/boot.scr'
+## Executing script at 02400000
+Loading env
+Loading Environment from FAT... OK
+isa_boot_count=2
+Boot counter variable found
+isa_boot_kernel=2
+Kernel type variable found
+Increasing boot count
+Saving Environment to FAT... OK
+###Loading factory kernel bootscript###
+875 bytes read in 1 ms (854.5 KiB/s)
+## Executing script at 02400000
+###Loading factory kernel###
+65030656 bytes read in 2690 ms (23.1 MiB/s)
+28942 bytes read in 3 ms (9.2 MiB/s)
+Saving Environment to FAT... OK
+Moving Image from 0x80000 to 0x200000, end=4100000
+## Flattened Device Tree blob at 2eff8a00
+ Booting using the fdt blob at 0x2eff8a00
+ Using Device Tree in place at 000000002eff8a00, end 000000002f002b0d
+
+Starting kernel ...
+
Booting Linux on physical CPU 0x0000000000 [0x410fd034]
Linux version 5.10.92-v8 (chris@mojobuild) (aarch64-buildroot-linux-gnu-gcc.br_real (Buildroot 2022.02.6) 10.4.0, GNU ld (GNU Binutils) 2.36.1) #33 SMP PREEMPT Mon Oct 24 19:47:01 CEST 2022
- random: fast init done
- Machine model: Raspberry Pi Compute Module 3 Rev 1.0
+ Machine model: Raspberry Pi Compute Module 3
efi: UEFI not found.
Reserved memory: created CMA memory pool at 0x0000000037400000, size 64 MiB
OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
@@ -144,15 +204,13 @@
percpu: Embedded 31 pages/cpu s87320 r8192 d31464 u126976
Detected VIPT I-cache on CPU0
CPU features: detected: ARM erratum 845719
- CPU features: kernel page table isolation forced ON by KASLR
- CPU features: detected: Kernel page table isolation (KPTI)
CPU features: detected: ARM erratum 843419
Built 1 zonelists, mobility grouping on. Total pages: 238896
Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes, linear)
Inode-cache hash table entries: 65536 (order: 7, 524288 bytes, linear)
mem auto-init: stack:off, heap alloc:off, heap free:off
- Memory: 820208K/970752K available (10560K kernel code, 1810K rwdata, 3592K rodata, 47424K init, 984K bss, 85008K reserved, 65536K cma-reserved)
+ Memory: 820212K/970752K available (10560K kernel code, 1810K rwdata, 3592K rodata, 47424K init, 984K bss, 85004K reserved, 65536K cma-reserved)
SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
ftrace: allocating 32481 entries in 127 pages
ftrace: allocated 127 pages with 7 groups
@@ -163,12 +221,11 @@
Tracing variant of Tasks RCU enabled.
rcu: RCU calculated value of scheduler-enlistment delay is 100 jiffies.
NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
- random: get_random_bytes called from start_kernel+0x3b8/0x580 with crng_init=1
+ random: get_random_bytes called from start_kernel+0x3b8/0x580 with crng_init=0
arch_timer: cp15 timer(s) running at 19.20MHz (phys).
clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x46d987e47, max_idle_ns: 440795202767 ns
sched_clock: 56 bits at 19MHz, resolution 52ns, wraps every 4398046511078ns
Console: colour dummy device 80x25
- printk: console [tty1] enabled
Calibrating delay loop (skipped), value calculated using timer frequency.. 38.40 BogoMIPS (lpj=19200)
pid_max: default: 32768 minimum: 301
LSM: Security Framework initializing
@@ -193,19 +250,19 @@
devtmpfs: initialized
Enabled cp15_barrier support
Enabled setend support
- KASLR enabled
+ KASLR disabled due to lack of seed
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns
futex hash table entries: 1024 (order: 4, 65536 bytes, linear)
pinctrl core: initialized pinctrl subsystem
DMI not present or invalid.
NET: Registered protocol family 16
- DMA: preallocated 1024 KiB GFP_KERNEL pool for atomic allocations
- DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for atomic allocations
- DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
+ DMA: preallocated 128 KiB GFP_KERNEL pool for atomic allocations
+ DMA: preallocated 128 KiB GFP_KERNEL|GFP_DMA pool for atomic allocations
+ DMA: preallocated 128 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
thermal_sys: Registered thermal governor 'step_wise'
cpuidle: using governor menu
hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
- ASID allocator initialised with 32768 entries
+ ASID allocator initialised with 65536 entries
Serial: AMBA PL011 UART driver
bcm2835-mbox 3f00b880.mailbox: mailbox enabled
raspberrypi-firmware soc:firmware: Attached to firmware from 2022-01-17T19:22:03, variant start
@@ -220,6 +277,10 @@
VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
FS-Cache: Loaded
CacheFiles: Loaded
+ simple-framebuffer 3eaf0000.framebuffer: framebuffer at 0x3eaf0000, 0x10a800 bytes, mapped to 0x(____ptrval____)
+ simple-framebuffer 3eaf0000.framebuffer: format=a8r8g8b8, mode=656x416x32, linelength=2624
+ Console: switching to colour frame buffer device 82x26
+ simple-framebuffer 3eaf0000.framebuffer: fb0: simplefb registered!
NET: Registered protocol family 2
IP idents hash table entries: 16384 (order: 5, 131072 bytes, linear)
tcp_listen_portaddr_hash hash table entries: 512 (order: 1, 8192 bytes, linear)
@@ -249,11 +310,9 @@
io scheduler mq-deadline registered
io scheduler kyber registered
bcm2708_fb soc:fb: FB found 1 display(s)
- Console: switching to colour frame buffer device 82x26
bcm2708_fb soc:fb: Registered framebuffer for display 0, size 656x416
- raspberrypi-clk: probe of soc:firmware:clocks failed with error -17
bcm2835-rng 3f104000.rng: hwrng registered
- vc-mem: phys_addr:0x00000000 mem_base=0x3ec00000 mem_size:0x40000000(1024 MiB)
+ vc-mem: phys_addr:0x00000000 mem_base=0x00000000 mem_size:0x00000000(0 MiB)
gpiomem-bcm2835 3f200000.gpiomem: Initialised: Registers at 0x3f200000
cacheinfo: Unable to detect cache hierarchy for CPU 0
brd: module loaded
@@ -272,14 +331,14 @@
OTG VER PARAM: 0, OTG VER FLAG: 0
Dedicated Tx FIFOs mode
- WARN::dwc_otg_hcd_init:1072: FIQ DMA bounce buffers: virt = ffffffc010461000 dma = 0x00000000f7810000 len=9024
+ WARN::dwc_otg_hcd_init:1072: FIQ DMA bounce buffers: virt = ffffffc0140c9000 dma = 0x00000000f7490000 len=9024
FIQ FSM acceleration enabled for :
Non-periodic Split Transactions
Periodic Split Transactions
High-Speed Isochronous Endpoints
Interrupt/Control Split Transaction hack enabled
- WARN::hcd_init_fiq:496: MPHI regs_base at ffffffc010075000
+ WARN::hcd_init_fiq:496: MPHI regs_base at ffffffc013f65000
dwc_otg 3f980000.usb: DWC OTG Controller
dwc_otg 3f980000.usb: new USB bus registered, assigned bus number 1
dwc_otg 3f980000.usb: irq 74, io mem 0x00000000
@@ -314,19 +373,19 @@
uart-pl011 3f201000.serial: cts_event_workaround enabled
3f201000.serial: ttyAMA0 at MMIO 0x3f201000 (irq = 99, base_baud = 0) is a PL011 rev2
printk: console [ttyAMA0] enabled
- KGDB: Registered I/O driver kgdboc
bcm2835-power bcm2835-power: Broadcom BCM2835 power domains driver
- sdhost: log_buf @ (____ptrval____) (cf3a0000)
+ sdhost: log_buf @ (____ptrval____) (ce7e3000)
mmc0: sdhost-bcm2835 loaded - DMA enabled (>1)
of_cfs_init
of_cfs_init: OK
+ uart-pl011 3f201000.serial: no DMA platform data
mmc0: new high speed MMC card at address 0001
mmcblk0: mmc0:0001 4FPD3R 3.64 GiB
mmcblk0boot0: mmc0:0001 4FPD3R partition 1 4.00 MiB
- Freeing unused kernel memory: 47424K
mmcblk0boot1: mmc0:0001 4FPD3R partition 2 4.00 MiB
- Run /init as init process
mmcblk0rpmb: mmc0:0001 4FPD3R partition 3 512 KiB, chardev (246:0)
+ Freeing unused kernel memory: 47424K
+ Run /init as init process
mmcblk0: p1 p2
systemd[1]: System time before build time, advancing clock.
NET: Registered protocol family 10
@@ -336,8 +395,10 @@
systemd[1]: systemd 250 running in system mode (-PAM -AUDIT -SELINUX -APPARMOR -IMA -SMACK -SECCOMP -GCRYPT -GNUTLS -OPENSSL -ACL +BLKID -CURL -ELFUTILS -FIDO2 -IDN2 -IDN -IPTC +KMOD -LIBCRYPTSETUP -LIBFDISK -PCRE2 -PWQUALITY -P11KIT -QRENCODE -BZIP2 -LZ4 -XZ -ZLIB -ZSTD -BPF_FRAMEWORK -XKBCOMMON -UTMP -SYSVINIT default-hierarchy=unified)
systemd[1]: Detected architecture arm64.
systemd[1]: Running in initial RAM disk.
+
+Welcome to Buildroot 2022.02.6!
+
systemd[1]: Hostname set to <Isatech-Router>.
- uart-pl011 3f201000.serial: no DMA platform data
systemd[1]: Unit initrd.target not found.
systemd[1]: Falling back to default.target.
systemd[1]: Queued start job for default target Multi-User System.
@@ -401,16 +462,16 @@
systemd[1]: Starting Network Configuration...
systemd[1]: Reloading.
systemd[1]: /etc/systemd/system.conf.d/watchdog.conf:1: Assignment outside of section. Ignoring.
- cfg80211: Loading compiled-in X.509 certificates for regulatory database
systemd[1]: /etc/systemd/system.conf.d/watchdog.conf:2: Assignment outside of section. Ignoring.
+ cfg80211: Loading compiled-in X.509 certificates for regulatory database
cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'
platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
cfg80211: failed to load regulatory.db
- systemd[1]: Found device /dev/mmcblk0p1.
+ systemd[1]: Found device /dev/ttyAMA0.
systemd[1]: Found device /dev/mmcblk0p2.
+ systemd[1]: Found device /dev/mmcblk0p1.
systemd[1]: Started Network Configuration.
systemd[1]: udev-fix.service: Deactivated successfully.
- systemd[1]: Found device /dev/ttyAMA0.
systemd[1]: Starting File System Check on /dev/mmcblk0p1...
systemd[1]: Starting File System Check on /dev/mmcblk0p2...
systemd[1]: Finished File System Check on /dev/mmcblk0p1.
@@ -419,42 +480,43 @@
systemd[1]: Mounting Boot partition...
systemd[1]: mnt-data.mount: Directory /mnt/data to mount over is not empty, mounting anyway.
systemd[1]: Mounting Data partition...
- EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!
FAT-fs (mmcblk0p1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
+ EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!
systemd[1]: Mounted Boot partition.
- systemd[1]: Starting Set root password...
- EXT4-fs (mmcblk0p2): recovery complete
- systemd[1]: update-rootpw.service: Deactivated successfully.
EXT4-fs (mmcblk0p2): mounted filesystem with journalled data mode. Opts: user_xattr,data=journal
- systemd[1]: Finished Set root password.
systemd[1]: Mounted Data partition.
systemd[1]: Reached target Local File Systems.
systemd[1]: Starting Journal Service...
systemd[1]: Commit a transient machine-id on disk was skipped because of a failed condition check (ConditionPathIsMountPoint=/etc/machine-id).
systemd[1]: Update is Completed was skipped because all trigger condition checks failed.
- systemd[1]: Started Journal Service.
+ systemd[1]: Starting Set root password...
+ systemd[1]: update-rootpw.service: Deactivated successfully.
+ systemd[1]: Finished Set root password.
+[ OK ] Finished Set root password.
+[ OK ] Started Journal Service.
+[ OK ] Finished Create Volatile Files and Directories.
+[ OK ] Started Network Name Resolution.
+[ OK ] Started Network Time Synchronization.
+[ OK ] Reached target Network.
+[ OK ] Reached target Host and Network Name Lookups.
+[ OK ] Reached target System Initialization.
+[ OK ] Reached target System Time Set.
+[ OK ] Reached target Timer Units.
+[ OK ] Listening on D-Bus System Message Bus Socket.
+[ OK ] Reached target Socket Units.
+[ OK ] Reached target Basic System.
+[ OK ] Started D-Bus System Message Bus.
+ Starting Dropbear SSH daemon...
+[ OK ] Started FRP sync daemon.
+ Starting Error counter reset...
+[ OK ] Started Serial Getty on ttyAMA0.
+[ OK ] Reached target Login Prompts.
+[ OK ] Started iSAtech maintenance tunnel.
+[ OK ] Started Dropbear SSH daemon.
+[ OK ] Finished Error counter reset.
+[ OK ] Reached target Multi-User System.
Welcome to Router
Router login: root
# i2cdet# i2cdetect -l
-i2c-1 i2c bcm2835 (i2c@7e804000) I2C adapter
