#Ubuntu 16.04 LTS: Broken SD Card Reader Support
General | 1 min | 3032
I am writing this post as a tutorial or a 'keep' note for myself, but I think it could be interesting for a lot of people. At work I'm using a Latitude Dell Laptop with dual boot (Ubuntu 16.04 LTS and Windows 10). The laptop has a SD card reader. Usually I work under Ubuntu while I am programming, and the SD card reader support is broken! But typing the following on a terminal, makes it works again:
sudo rmmod sdhci_pci sdhci_acpi sdhci sudo modprobe sdhci debug_quirks2="0x10000" sudo modprobe sdhci_pci sdhci_acpi sdhci
It seems to be a problem since Linux kernel version 4.1.8. A bug report he...
#Rapberry Pi: Preempt-RT Kernel Performance on Rasbperry PI 3 Model B+
Real Time Systems | 3 min | 10902
The Raspberry Pi 3 Model B+ (Fig. 1) is now on sale and I bought one two weeks ago. The main modifications are the followings:
- A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU
- Dual-band 802.11ac wireless LAN and Bluetooth 4.2
- Faster Ethernet (Gigabit Ethernet over USB 2.0)
- Power-over-Ethernet support (with separate PoE HAT)
- Improved PXE network and USB mass-storage booting
- Improved thermal management
Fig. 1: Raspberry Pi 3 Model B+
The Raspberry Pi uses now the LAN2515 chip from Microchip instead of the LAN9514 for Ethernet and the USB Ports.
If you are looking for some Benchmarkin...
#Raspberry PI Zero W: Preempt-RT Kernel Performance
Real Time Systems | 2 min | 7120
Today I patched the kernel of a Raspberry Pi Zero W with Preempt-RT. I used the repo TiejunChina.
Update 18.03.2018: The official Preempt-RT patched Rasbian repo is here.
##~/rpi-kernel$ git clone https://github.com/TiejunChina/linux.git # update 18.03.2018: old repository## ~/rpi-kernel$ git clone https://github.com/raspberrypi/linux.git # update 18.03.2018: new repository ~/rpi-kernel$ cd linux ~/rpi-kernel/linux$ git checkout rpi-4.14.y-rt # today the kernel version is 4.14.22 # with rt17 resulting in 4.14.22-rt17+
You can find a complet...