Prestigio Smartbook 116C

Hardware Set

Prestigio Smartbook 116C is a netbook 11.6" based on Intel Cherry Trail Soc with Atom Z8350 and i915 subsystem Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Series. Its strength points are the light weight (about 1Kg) and an amazing antiglare screen 11.6" with resolution of 1980x1080. Its quad-core CPU is very low consumption (about 0.5W/h) and it is combined with a 8.000mA/h battery.

The power adapter is a 5V 3A with a jack 1.35mm (very similar to the ones used for the new Rasperry Pi).

Shortcomings

The internal eMMC 32Gb is quite slow compared to 2.5" SSD and the RAM installed is about 2Gb (but a second SoDIMM slot is reported free).

General Specifications

Smartbook 11.6′′ Full HD (1920 x 1080) IPS with OS Windows 10 Home 32bit preinstalled, Quad Core Intel® AtomTM Z8350 up to 1.92GHz, 2GB RAM, 32GB ROM expandable slot for microSDTM card up to 128GB 8000 mAh Li-pol Battery (up to 5h video playing), front-panel webcam 0.3MP, BT 4.0, Wi-Fi: 802.11b/g/n, USB 3.0, USB 2.0, Mini HDMI port,

• Dimension: 276.9 x 189.2 x 14.3 mm
• Weight: 1059g

Model PSB116C01BFH

• SoC WEIBU Y116CR210
• Intel Atom x5-Z8350 CPU @ 1.44GHz
• Intel HD Graphics 1920 x 1080 integrated
• Intel SST Audio Device (WDM) integrated
• Realtek RTL8723BS Wireless LAN 802.11n SDIO Network Adapter
• SanDisk DF4032 32Gb
• WebCam Lenovo EasyCamera integrated
• BIOS AmiTrend 4Mb with ACPI and EFI support
• Hynix Semiconductor SoDIMM PC-104 DDR3 1600 MHz (0.6 ns)
• 2 USB ports, 1 HDMI port, 1 SD/MMC reader bay, 1 power jack-in 1.35mm, 1 jack-in 2.5mm audio in/out

Unsecure EFI boot at 32bit

It is required to copy the bootia32.efi to /efi/boot/bootia32.efi because the Smartbook works at 64bit but the BIOS EFI boot works at 32 bit.

Compatibility with Ubuntu 18.04.1

Almost it works smootly with Ubuntu 18.04.1 amd64 LTS out-of-the-box however some problems and freezes might arises. Here how to cope with them in order to bring Ubuntu work in full.

intel_idle.max_cstate=5 sdhci.debug_quirks2=0x404 tsc=reliable force_tsc_stable=1 clocksource=tsc clocksource_failover=tsc

The overall cmdline tweaks are here above presented and they should be used into each /boot/grub/grub.cfg linux cmdline

Audio

Audio requires some tweaks to work:

git clone https://github.com/plbossart/UCM.git
sudo cp -rf ~/UCM/bytcr-rt5651 /usr/share/alsa/ucm
sudo cp ~/UCM/bytcr-rt5651/asound.state /var/lib/alsa
echo "blacklist snd_hdmi_lpe_audio" | sudo tee /etc/modprobe.d/blacklist_snd_hdmi_lpe_audio.conf

cd /usr/share/alsa/ucm
sudo ln -sf bytcr-rt5651 bytcr-rt5651-stereo-spk-in2-mic
cd bytcr-rt5651-stereo-spk-in2-mic
ln -sf bytcr-rt5651.conf bytcr-rt5651-stereo-spk-in2-mic.conf

after the reboot use pavucontrol to select the input device

Video

The following set of options should be generally safe to enable:

i915.modeset=1 i915.enable_dc=1 i915.enable_fbc=1 i915.semaphores=1 i915.enable_guc=3

On Linux 4.16+, GuC firmware loading and submission is now handled by the enable_guc parameter in place of the former enable_guc_loading=1 and enable_guc_submission=1 insert the code here parameters. Adjust as needed.

Intel Cherry Trail

The Cherry Trail architecture like the i915 might freeze the system in CPU powersave state C6

In order to prevent this, it better to apply this workaround on the kernel cmdline

intel_idle.max_cstate=5

TSC and ACPI subsystems

ACPI could not be switched off otherwise internal and external SD/MMC would not work and some tweaks into kernel cmdline about the TSC are needs.

These are needs to make SDIO PIC working and thus the SD/MMC internal (/dev/mmcblk0) and into the bay (/dev/mmcblk2), both

tsc=reliable force_tsc_stable=1 clocksource=tsc clocksource_failover=tsc

SD/MMC bay reader

SD/MMC card reader requires some tweaks into the kernel cmdline to works with any SD/MMC cards

sdhci.debug_quirks2=0x404

Debug cmdline settings

Just in case it would be necessary, these are the cmdline tweaks to obtain a lot of log for debugging

nosplash debug ignore_loglevel log_buf_len=10M print_fatal_signals=1 LOGLEVEL=8 earlyprintk=vga,keep sched_debug

Compatibility with Chromium OS

The last build test almost working but not the audio is Camd64OS_R67-10575.B-Special.7z and it boots with this bootia32.efi EFI IA32 image. Chromium OS is an open-source project that aims to build an operating system that provides a fast, simple, and more secure computing experience for people who spend most of their time on the web.