Здравствуйте.

А можно посмотреть результат работы команды ( файлик a.txt ):

$dmesg > a.txt

на рабочей, с загруженным Linux'ом, плате Rainbow ?

На ix86 сделано так потому что делалось с оглядкой на конечных пользователей, которые не будут новый конфиг для каждой конкретной платы писать. На ix86 есть статусные и информационные регистры из которых можно всегда прочесть какими характеристика обладает та или иная железка (например, сколько строк/колонок у памяти). А вообще поддержка кадой индивидуальной платы закладывается в OS, это прост Вам, наверное, не приходилось заводить какунить PC-шную мать пытаясь использовать все установленные на ней сенсоры и прочие финтифлюшки. Посмотрите, для примера, комментарии в CVS changelog для кода и сам код инициализации чипсетов во freebsd... там ужас что творится!
Но со встраиваемыми решениями это нормальная ситуация, плату один раз собрали, в софт сразу, зная что есть на плате, заложили все параметры, настроили чтоб работало, встроили и забыли.

Сообщение отредактировал Odiemus - May 13 2007, 09:32

Народ, помогите!
Не запускается ФС из RAM... Юзаю самодельную плату похожую на RainBow и читаю активно heavy-online. От них же взял и образ ФС.

u-boot> bootm 10000000 10200000
## Booting image at 10000000 ...
Image Name:
Image Type: ARM Linux Kernel Image (gzip compressed)
Data Size: 932967 Bytes = 911.1 kB
Load Address: 20008000
Entry Point: 20008000
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
## Loading Ramdisk Image at 10200000 ...
Image Name:
Image Type: ARM Linux RAMDisk Image (gzip compressed)
Data Size: 1807723 Bytes = 1.7 MB
Load Address: 20288000
Entry Point: 20288000
Verifying Checksum ... OK

Starting kernel ...

Linux version 2.6.20 (root@linux) (gcc version 3.4.6) #9 Tue May 15 21:27:29 EEST 2007
CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c0003177
Machine: Router-board
Memory policy: ECC disabled, Data cache writeback
Clocks: CPU 180 MHz, master 60 MHz, main 20.000 MHz
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists. Total pages: 16256
Kernel command line: root=/dev/mem initrd=0x20288000,0x30000
AT91: 96 gpio irqs in 3 banks
PID hash table entries: 256 (order: 8, 1024 bytes)
Console: colour dummy device 80x30
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 64MB = 64MB total
Memory: 62732KB available (1692K code, 152K data, 88K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
NET: Registered protocol family 16
Generic PHY: Registered new driver
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 2048 (order: 1, 8192 bytes)
TCP bind hash table entries: 1024 (order: 0, 4096 bytes)
TCP: Hash tables configured (established 2048 bind 1024)
TCP reno registered
checking if image is initramfs...it isn't (bad gzip magic numbers); looks like an initrd
Freeing initrd memory: 192K
NetWinder Floating Point Emulator V0.97 (double precision)
JFFS2 version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
io scheduler noop registered
io scheduler anticipatory registered (default)
at91_spi: Baud rate set to 5000000
AT91 SPI driver loaded
atmel_usart.0: ttyS0 at MMIO 0xfefff200 (irq = 1) is a ATMEL_SERIAL
atmel_usart.1: ttyS1 at MMIO 0xfffc4000 (irq = 7) is a ATMEL_SERIAL
RAMDISK driver initialized: 8 RAM disks of 4096K size 1024 blocksize
LXT970: Registered new driver
LXT971: Registered new driver
at91_ether: Your bootloader did not configure a MAC address.
eth0: Link now 100-FullDuplex
eth0: AT91 ethernet at 0xfefbc000 int=24 100-FullDuplex (00:00:00:00:00:00)
eth0: Intel LXT971A PHY
physmap platform flash device: 01000000 at 10000000
physmap-flash.0: Found 1 x16 devices at 0x0 in 16-bit bank
Amd/Fujitsu Extended Query Table at 0x0040
physmap-flash.0: CFI does not contain boot bank location. Assuming top.
number of CFI chips: 1
cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness.
RedBoot partition parsing not available
kobject_add failed for physmap-flash.0 with -EEXIST, don't try to register things with the same name in the same directory.
block2mtd: version $Revision: 1.30 $
mice: PS/2 mouse device common for all mice
TCP cubic registered
NET: Registered protocol family 1
NET: Registered protocol family 17
RAMDISK: Couldn't find valid RAM disk image starting at 0.
VFS: Cannot open root device "mem" or unknown-block(0,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

Кернел в пенике? - успакаивайте его 8)
по теме...
Вызывает подозрение Вот эта строка...
Kernel command line: root=/dev/mem initrd=0x20288000,0x30000
чтото мне подсказывает что - там нужно не 30000 а 300000
тем более...
если 30000 - и Вы хотите пощюпать busybox - не удивительно....

.

Увеличил размер диска:
...
RAMDISK driver initialized: 8 RAM disks of 8192K size 1024 blocksize
...

Передал initrd больше места:
...
Kernel command line: root=/dev/mem initrd=0x20288000,500000
...

Все равно кернел в панике

Смущает это:
RAMDISK: Couldn't find valid RAM disk image starting at 0.
Образ диска ведь запакован, и что-то не видно надписи (как в ядре), что он распаковывается. Или я что-то не понимаю?.. Может при компиляции ядра надо указать что-то еще кроме CONFIG_BLK_DEV_RAM, CONFIG_BLK_DEV_INITRD и CONFIG_EXT2_FS?

Проверяйте переменные окружения, всё должно работать.
(сейчас нет rainbow под рукой, лог из ucrouter, для дополнения так сказать)
Если собирать по инструкции от heavy, то должно получаться так:




boot 1.0 32Mb 45MHz (Jan 25 2005 - 01:40:16)

SDRAM Test...

Ok


Uncompressing image...


Done



U-Boot 1.1.1 (Sep 14 2006 - 17:46:55)

U-Boot code: 20F00000 -> 20F1BD8C BSS: -> 20F206A4
RAM Configuration:
Bank #0: 20000000 32 MB
AMD: 29LV160B (16 M, bottom sector)
Flash: 2 MB
DataFlash:AT45DB321
Nb pages: 8192
Page Size: 528
Size= 4325376 bytes
Logical address: 0xC0000000
Area 0: C0000000 to C0007FFF (RO)
Area 1: C0008000 to C001FFFF (RO)
Area 2: C0020000 to C0027FFF
Area 3: C0028000 to C041FFFF
In: serial
Out: serial
Err: serial
eth: setting MAC address to 12:34:56:78:9a:bc
PHY: RTL8201(L detected
Link: cable disconnected
Link: cable disconnected
MAC: error during MII initialization
Hit any key to stop autoboot: 0
## Booting image at 20a00000 ...
Image Name:
Image Type: ARM Linux Kernel Image (gzip compressed)
Data Size: 915757 Bytes = 894.3 kB
Load Address: 20008000
Entry Point: 20008000
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
## Loading Ramdisk Image at 20c0000
Image Name:
Image Type: ARM Linux RAMDisk Image (gzip compressed)
Data Size: 1824589 Bytes = 1.7 MB
Load Address: 20288000
Entry Point: 20288000
Verifying Checksum ... OK

Starting kernel ...

Linux version 2.6.16 (root@sunny) (gcc version 3.4.6) #1 Thu Apr 26 15:00:56 MSD
2007
CPU: ARM920Tid(wb) [41129200] revision 0 (ARMv4T)
Machine: uCrouter
Memory policy: ECC disabled, Data cache writeback
Clocks: CPU 179 MHz, master 44 MHz, main 18.432 MHz
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists
Kernel command line: root=/dev/ram rw initrd=0x20288000,0x500000 ramdisk_size=50
00 console=ttyS0,115200 mem=32M
AT91: 128 gpio irqs in 4 banks
PID hash table entries: 256 (order: 8, 4096 bytes)
Console: colour dummy device 80x30
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 32MB = 32MB total
Memory: 25332KB available (1508K code, 339K data, 88K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
checking if image is initramfs...it isn't (no cpio magic); looks like an initrd
Freeing initrd memory: 5120K
NET: Registered protocol family 16
usbcore: registered new driver usbfs
usbcore: registered new driver hub
io scheduler noop registered
io scheduler anticipatory registered (default)
AT91 Real Time Clock driver.
AT91 SPI driver loaded
AT91 Watchdog Timer enabled (5 seconds, nowayout=1)
at91_usart.0: ttyS0 at MMIO 0xfefff200 (irq = 1) is a AT91_SERIAL
at91_usart.1: ttyS1 at MMIO 0xfffc4000 (irq = 7) is a AT91_SERIAL
RAMDISK driver initialized: 16 RAM disks of 5000K size 1024 blocksize
eth0: AT91 ethernet at 0xfefbc000 int=24 10-HalfDuplex (12:34:56:78:9a:bc)
eth0: Realtek RTL8201(L PHY
physmap flash device: 200000 at 10000000
phys_mapped_flash: Found 1 x16 devices at 0x0 in 16-bit bank
Amd/Fujitsu Extended Query Table at 0x0040
number of CF
cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness.
RedBoot partition parsing not available
at91_dataflash: AT45DB321B detected [spi0] (4325376 bytes)
Creating 3 MTD partitions on "AT45DB321B.spi0":
0x00000000-0x00042000 : "bootloader"
0x00042000-0x0014a000 : "kernel"
0x0014a000-0x00420000 : "filesystem"
at91_cf: irqs det #64, io #0
at91_ohci at91_ohci: AT91 OHCI
at91_ohci at91_ohci: new USB bus registered, assigned bus number 1
at91_ohci at91_ohci: irq 23, io mem 0x00300000
usb usb1: Product
usb usb1: Manufacturer: Linux 2.6.16 ohci_hcd
usb usb1: SerialNumber: at91
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
udc: at91_udc version 8 March 2005
mice: PS/2 mouse device common for all mice
i2c /dev entries driver
at91_i2c at91_i2c: AT91 i2c bus driver.
NET: Registered protocol family 2
IP route cache hash table entries: 512 (order: -1, 2048 bytes)
TCP established hash table entries: 2048 (order: 1, 8192 bytes)
TCP bind hash table entries: 2048
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
TCP bic registered
NET: Registered protocol family 1
NET: Registered protocol family 17
RAMDISK: Compressed image found at block 0
VFS: Mounted root (ext2 filesystem).
Freeing init memory: 88K
init started: BusyBox v1.1.2 (2006.05.05-15:29+0000) multi-call binary


Starting system...
usb 1-2: new low speed USB device using at91_ohci and address 2
Configuring loopback interface...
usb 1-2: device descriptor read/64, error -110
Configuring eth0: 192.168.2.77...
Starting telnetd...


BusyBox v1.1.2 (2006.05.05-15:29+0000) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

[root@arm /]$usb 1-2: device descriptor read/64, error -110
usb 1-2: new low speed USB device using at91_ohci and address 3
usb 1-2: device descriptor read/64, error -110
usb 1-2: device descriptor read/64, error -110
usb 1-2: new low speed USB device using at91_ohci and address 4
usb 1-2: device not accepting address 4, error -110
usb 1-2: new low speed USB device using at91_ohci and address 5
usb 1-2: device not accepting address 5, error -110

[root@arm /]$dmesg
Linux version 2.6.16 (root@sunny) (gcc version 3.4.6) #1 Thu Apr 26 15:00:56 MSD
2007
CPU: ARM920Tid(wb) [41129200] revision 0 (ARMv4T)
Machine: uCrouter
Memory policy: ECC disabled, Data cache writeback
On node 0 totalpages: 8192
DMA zone: 8192 pages, LIFO batch:1
DMA32 zone: 0 pages, LIFO batch:0
Normal zone: 0 pages, LIFO batch:0
HighMem zone: 0 pages, LIFO batch:0
Clocks: CPU 179 MHz, master 44 MHz, main 18.432 MHz
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists
Kernel command line: root=/dev/ram rw initrd=0x20288000,0x500000 ramdisk_size=50
00 console=ttyS0,115200 mem=32M
AT91: 128 gpio irqs in 4 banks
PID hash table entries: 256 (order: 8, 4096 bytes)
Console: colour dummy device 80x30
Dentry cache hash table entries: 8192 (order: 3, 32
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 32MB = 32MB total
Memory: 25332KB available (1508K code, 339K data, 88K init)
Calibrating delay loop... 89.70 BogoMIPS (lpj=448512)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
checking if image is initramfs...it isn't (no cpio magic); looks like an initrd
Freeing initrd memory: 5120K
NET: Registered protocol family 16
usbcore: registered new driver usbfs
usbcore: registered new driver hub
io scheduler noop registe
io scheduler anticipatory registered (default)
AT91 Real Time Clock driver.
AT91 SPI driver loaded
AT91 Watchdog Timer enabled (5 seconds, nowayout=1)
at91_usart.0: ttyS0 at MMIO 0xfefff200 (irq = 1) is a AT91_SERIAL
at91_usart.1: ttyS1 at MMIO 0xfffc4000 (irq = 7) is a AT91_SERIAL
RAMDISK driver initialized: 16 RAM disks of 5000K size 1024 blocksize
eth0: AT91 ethernet at 0xfefbc000 int=24 10-HalfDuplex (12:34:56:78:9a:bc)
eth0: Realtek RTL8201(L PHY
physmap flash device: 200000 at 10000000
phys_mapped_flash: Found 1 x16 devices at 0x0 in 16-bit bank
Amd/Fujitsu Extended Query Table at 0x0040
number of CFI chips: 1
cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness.
RedBoot partition parsing not available
at91_dataflash: AT45DB321B detected [spi0] (4325376 bytes)
Creating 3 MTD partitions on "AT45DB321B.spi0":
0x00000000-0x00042000 : "bootloader"
0x00042000-0x0014a000 : "kernel"
0x0014a000-0x00420000 : "filesystem"
at91_cf: irqs det #64, io #0
at91_ohci at91_ohci: starting AT91
at91_ohci at91_ohci: AT91 OHCI
drivers/usb/core/inode.c: creating file 'devices'
drivers/usb/core/inode.c: creating file '001'
at91_ohci at91_ohci: new USB bus registered, assigned bus number 1
at91_ohci at91_ohci: irq 23, io mem 0x00300000
at91_ohci at91_ohci: resetting from state 'reset', control = 0x0
at91_ohci at91_ohci: OHCI controller state
at91_ohci at91_ohci: OHCI 1.0, NO legacy support registers
at91_ohci at91_ohci: control 0x083 HCFS=operational CBSR=3
at91_ohci at91_ohci: cmdstatus 0x00000 SOC=0
at91_ohci at91_ohci: intrstatus 0x00000044 RHSC SF
at91_ohci at91_ohci: intrenable 0x8000001a MIE UE RD WDH
at91_ohci at91_ohci: hcca frame #0005
at91_ohci at91_ohci: roothub.a 02000202 POTPGT=2 NPS NDP=2(2)
at91_ohci at91_ohci: roothub.b 00000000 PPCM=0000 DR=0000
at91_ohci at91_ohci: roothub.status 00008000 DRWE
at91_ohci at91_ohci: roothub.portstatus [0] 0x00000100 PPS
at91_ohci at91_ohci: roothub.portstatus [1] 0x00000100 PPS
at91_ohci at91_ohci: created debug files
usb usb1: default language 0x0409
usb usb1: new device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: AT91 OHCI
usb usb1: Manufacturer: Linux 2.6.16 ohci_hcd
usb usb1: SerialNumber: at91
usb usb1: uevent
usb usb1: device is self-powered
usb usb1: configuration #1 chosen from 1 choice
usb usb1: adding 1-0:1.0 (config #1, interface 0)
usb 1-0:1.0: uevent
hub 1-0:1.0: usb_probe_interface
hub 1-0:1.0: usb_probe_interface - got id
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
hub 1-0:1.0: standalone hub
hub 1-0:1.0: no power sw
hub 1-0:1.0: global over-current protection
hub 1-0:1.0: power on to power good time: 4ms
hub 1-0:1.0: local power source is good
hub 1-0:1.0: no over-current condition exists
hub 1-0:1.0: state 7 ports 2 chg 0000 evt 0000
drivers/usb/core/inode.c: creating file '001'
udc: at91_udc version 8 March 2005
mice: PS/2 mouse device common for all mice
i2c /dev entries driver
at91_i2c at91_i2c: AT91 i2c bus driver.
NET: Registered protocol family 2
IP route cache hash table entries: 512 (order: -1, 2048 bytes)
TCP established hash table entries: 2048 (order: 1, 8192 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
TCP bic registered
NET: Registered protocol family 1
NET: Registered protocol family 17
RAMDISK: Compressed image found at block 0
hub 1-0:1.0: state 7 ports 2 chg 0000 evt 0004
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00010101 CSC PPS CCS
hub 1-0:1.0: port 2, status 0101, change 0001, 12 Mb/s
VFS: Mounted root (ext2 filesystem).
Freeing init memory: 88K
hub 1-0:1.0: debounce: port 2: total 100ms stable 100ms status 0x101
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: new low speed USB device using at91_ohci and address 2
at91_ohci at91_ohci: urb c18a0c00 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0c00 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0c00 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: device descriptor read/64, error -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: device descriptor read/64, error -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: new low speed USB device using at91_ohci and address 3
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: device descriptor read/64, error -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0in 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: device descriptor read/64, error -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: new low speed USB device using at91_ohci and address 4
at91_ohci at91_ohci: urb c18a0360 path 2 ep0out 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0out 5ec20000 cc 5 --> status -110
usb 1-2: device not accepting address 4, error -110
at91_ohci at91_ohci: GetStatus roothub.portstatus [1] = 0x00100303 PRSC LSDA PPS
PES CCS
usb 1-2: new low speed USB device using at91_ohci and address 5
at91_ohci at91_ohci: urb c18a0360 path 2 ep0out 5ec20000 cc 5 --> status -110
at91_ohci at91_ohci: urb c18a0360 path 2 ep0out 5ec20000 cc 5 --> status -110
usb 1-2: device not accepting address 5, error -110
hub 1-0:1.0: state 7 ports 2 chg 0000 evt 0004
[root@arm /]$

Вот же, Вам ниже написали, смотрим как там
...
Kernel command line: root=/dev/ram rw initrd=0x20288000,0x500000 ramdisk_size=50
...
тоесть не
initrd=0x20288000,500000
а
initrd=0x20288000,0x500000

Спасибо всем, помогло! Я потом сделал запуск сразу с флешки: root=/dev/mtdblock1 и т.д... Ни у кого с Ethernet проблем не было? Если кабель высунут при запуске, то u-boot пишет:

...
MAC: error during MII initialization
...

а ядро пишет:

...
eth0: Link down.
...

И потом, сунув кабель, все равно пинги не ходят. Получается, потом линух не анализирует активность интерфейса? Я использую LXT971A.

на этот месадж не обращайте внимания!
а вот если при u-bootе кабель не вотткнут - езернет не проинициализируется
ну и соответсвенно в линуксе он будет down
пробуйте в линуксе
ifconfig down
вставить шнурок
ifconfig up

должно помоч!

Спасибо, помогло!
Но, согласитесь, это не выход. Должен быть механизм автоматического определия наличия линии и поднятия интерфейса. На обычных PC мы же не набираем каждый раз ifconfig up, а интерфейс подымается автоматически. Наверно в драйвер надо добавить что-то?

Здравствуйте!

Скажите, сколько времени происходит загрузка linuxa ?

Для AT91SAM9261 - строчка запуска ядра содержит : ip=172.30.10.36:172.30.10.141:172.30.10.1:255.255.255.0
- свой IP, хост, шлюз, маска. После этого ethernet поднимается сам при старте.

Ну кто-нибуть может сказать сколько времени у него длится загрузка linux.

Если не трудно то по этапно:
от включения питания до окончания.
Заранее спасибо

От включения питания до начала распаковывания ядра около 20с, от распаковки до полной готовности около 40с.

А функциональность ядра приближенна к полной ?
Сколько времени займет загрузка если оставить только поддержку USB и так по мелочам, необходимое ?