When I bought Samsung Chromebook friend started “nbench” on it. So I did same on my conference laptop. None of devices won…

Idea of testing cpu power was sitting somewhere at back of my head and finally I decided to just run one simple command available on nearly every GNU/Linux based system: “openssl speed”. Sure, on some systems it will use hardware accelerators, on others (or not) some options enabled to get more speed (like ARM assembly version which is not enabled in Debian/Ubuntu systems). But it is something what anyone can run at home.

Table may be hard to decipher so I also give it as Google Docs. It also has few more devices listed and whole tables (one below is for 8192 size samples).

Devices in table are:

• my Intel Core i7-2600K desktop
• my Intel U7300 (ultra low voltage) conference laptop
• Exynos5 Dual powered Samsung ARM Chromebook
• Exynos4 Dual powered Tizen development platform (got rid of it today)
• i.mx515 powered Efika MX Smartbook
• Beaglebone with AM335x cpu
• Sheevaplug (as only armv5te device which can compare with other entries)

Devices were running different versions of OpenSSL under different systems. It is listed in Google Docs document.

Most interesting columns are U7300 and Exynos 5250 ones — 3 years old laptop which I bought for conferences compared to Chromebook. Looks like for next conferences/events I will rather go with Chromebook not UL30A. This will give me one or two hours of battery life less but it is much lighter device at same time. But have to test it first for few days to check is it comfortable enough for daily use.

All rights reserved © Marcin Juszkiewicz
Let’s compare some cpu ;) was originally posted on Marcin Juszkiewicz website

When I published my last post about ARM boards there were many questions and suggestions with interesting devices. Thank You all for it.

But there were also suggestions about ARM9 or ARM11 based devices. So I decided that it is good time to write what interest me now in ARM world.

But first some inventory. I had/used/have several devices with ARM cpu:

• StrongARM (armv4) one:

  • Sharp Zaurus SL-5500 (which took me to ARM world)

• ARM920 (armv4t) ones:

  • Openmoko GTA01 bv3, bv4 (s3c2410)
  • EDB9301 (EP9301 cpu)
  • Sim-One (EP9307)

• ARM926 (armv5te) ones:

  • Sharp Zaurus sl-5600 (pxa250)
  • Sharp Zaurus c760/sl-6000 (pxa255)
  • Sharp Zaurus sl-c3000 (pxa272)
  • Sheevaplug (kirkwood)
  • Atmel devboards (at91sam9263, at91sam9m10)
  • ST-Microelectronics/ST-Ericsson NDK-15, NHK-15 (st88n15)
  • Nokia 770 (omap1710)
  • Linksys NSLU2 (ixp425 iirc)

• ARM1136 (armv6) ones:

  • Nokia N810 (omap2430)
  • Bug r1.0, r1.2 (i.mx31)

• Cortex-A8 (armv7a) ones:

  • Beagleboard B7, B7, C3 (omap3430)
  • Nokia N900 (omap3430)
  • Nexus S (exynos3)
  • Genesi Efika MX Smartbook (i.mx51)
  • Freescale Quickstart (i.mx53)

• Cortex-A9 (armv7a) ones:

  • Pandaboard EA1, A1 (omap4430)
  • Archos G9 80 (omap4430)

All of that during last 8 years. Most of my ARM live so far was around ARM926 based devices (some of them still can not be listed here) and I do not want to go there again. Kirkwood core was fastest one with 1.2GHz clock and 512MB of RAM it was really fast machine. I only missed Serial ATA in my Sheevaplug (rev 1.0) but even with hard drive on USB it was nice improvement.

Then I played a bit with ARM11 processors. Ok, they were faster than most of ARM9 cpus but I already had experience with Sheevaplug. And after few months first Cortex-a8 board landed on my desk — I got Beagleboard B7 from Bug labs as test platform for their new device. This was improvement!

I still remember my reaction when connected it to normal LCD monitor and saw it used at 720p resolution (1680×1050 was a bit hard for omap3). Moved to Nokia N900 few months later and found that fast cpu means nothing when paired with slow storage and not enough memory for system.

So today I prefer to not look below Cortex-A9 (or comparable cores like ones from Qualcomm or Marvell). Hope to play one day with Cortex-A5 (which should replace ARM926 one day) just to see how low-end armv7a cpu behave.

And wait for ARMv8 to hit market.

All rights reserved © Marcin Juszkiewicz
What interest me in ARM world was originally posted on Marcin Juszkiewicz website

Few months ago one of my friends borrowed SheevaPlug from me. About two weeks later he gave it back — bricked… I did not had time to play with it so it landed on shelf.

Yesterday I took it and decided to get it back to live. Requirements:

• bricked SheevaPlug (v1.0 without SATA)
• power cable
• mini usb cable
• usb thumb drive
• OpenOCD (“apt-get install openocd”)
• cross compiler (“apt-get install gcc-arm-linux-gnueabi” under Ubuntu)
• U-Boot sources (HEAD of mainline)
• Linux sources (also HEAD of mainline)
• serial terminal (picocom, minicom, screen etc)
• few terminals or terminal multiplexer (I used tmux)

Then:

• Connected power and mini usb cables to SheevaPlug. Desktop recognized usb-serial device as /dev/ttyUSB1.
• Connected to it with serial terminal. Nothing appeared there of course ;)
• Run OpenOCD: “cd /tmp/;sudo openocd -f /usr/share/openocd/scripts/board/sheevaplug.cfg -s /usr/share/openocd/scripts”. SheevaPlug was detected.
• Connected to OpenOCD: “telnet localhost 4444″.
• Built U-boot:

export CROSS_COMPILE=arm-linux-gnueabi-
make mrproper
make sheevaplug_config
make u-boot.kwb

• Copied “u-boot” to “/tmp/uboot.elf” and used “reset;sheevaplug_init;load_image u-boot.elf;resume 0×00600000″ — landed in U-Boot ;)
• There is “sheevaplug_reflash_uboot” macro but it was not working for me. So I used U-Boot to flash itself:

Marvell>> usb start
Marvell>> fatload usb 0:1 0x0800000 u-boot.kwb
Marvell>> nand erase 0x0 0xa0000
Marvell>> nand write 0x0800000 0x0 0xa0000
Marvell>> reset

• Went to Ångström online image builder and built small busybox based image.
• Unpacked tarball into /tmp/initfs, added /dev/ttyS0 node.
• Built Linux kernel:

export CROSS_COMPILE=arm-linux-gnueabi-
make mrproper
make kirkwood_config
make menuconfig (set INITRAMFS_SOURCE to /dev/initfs)
make uImage

• Copied “arch/arm/boot/uImage” to USB thumb drive and inserted it into SheevaPlug.
• Booted image:

Marvell>> set ethaddr 'c0:ff:ee:c0:ff:ee'
Marvell>> set bootargs 'console /dev/ttyS0,115200 rw'
Marvell>> usb start;fatload usb 0:1 0x800000 /uImage;bootm 0x800000

• Landed in nice and small Ångström distribution image ;)
• Went to Ångström online image builder and built console image (task-base based).
• Built Linux kernel (this time without initramfs):

export CROSS_COMPILE=arm-linux-gnueabi-
make menuconfig (unset INITRAMFS_SOURCE)
make uImage

• Copied “arch/arm/boot/uImage” to USB thumb drive and inserted it into SheevaPlug.
• Prepare NAND for UBI:

# mount none /dev -t devtmpfs
# udhcpc eth0
# opkg-cl update
# opkg-cl install mtd-utils
# ubiformat /dev/mtd2
# ubiattach -p /dev/mtd2
# ubimkvol /dev/ubi0 -N rootfs -s 490MiB
# ubiupdatevol /dev/ubi0_0 /media/sda1/angstrom-task-base.ubifs
# mount -t ubifs ubi0:rootfs /media/rootfs
# chown -R root:root /media/rootfs
# cp /media/sda1/uImage /media/rootfs/boot
# sync
# reboot

• Another reconfiguration in U-Boot:

Marvell>> bootargs 'console=ttyS0,115200 rw ubi.mtd=2 rootfstype=ubifs root=ubi:rootfs'
Marvell>> bootcmd 'ubi part nand0,2; ubifsmount rootfs; ubifsload 0x800000 /boot/uImage;bootm 0x800000'
Marvell>> mtdids 'nand0=orion_nand'
Marvell>> set mtdparts 'mtdparts=orion_nand:512k(uboot),4m@1m(kernel),507m@5m(rootfs)'
Marvell>> save
Marvell>> reset

And now my SheevaPlug is operational again. Boots from NAND with latest U-Boot and Linux. There is around 440MB free still on NAND (not counting 4MB partition where kernel was expected to be). I can put it back on shelf now.

The only parts which I needed to compile were U-Boot and Linux kernel. I could skip bootloader and use binary image from Internet but prefer to know what my machines run (and building U-Boot is really easy). Initramfs support in Linux is real live saver as I did not had to play with initrd etc — just build image and boot it. The only problem was that devtmpfs was not auto mounted (even if option in kernel was selected).

I could also use one of those “easy installers” made by PlugComputer community but I found such solutions more complicated (fetching binaries, finding requirements etc) than the one I used.

All rights reserved © Marcin Juszkiewicz
Unbricked my old SheevaPlug was originally posted on Marcin Juszkiewicz website