I noticed that the BMW’s iDrive startup is immediate, no bootup process. I suppose that other systems work like that as well. How do they achieve this?
Usually the car IVI (in vehicle infotainment)system is tightly coupled with the telematics system which provides data about your car’s overall health. The System on Chip’s which are used generally have two or more cores to handle the following
1. User experience, Navigation, audio playback, graphics streaming etc which concerns end user interaction
2. Critical vehicle services like ECU/Telematics which must be very stable.
High end cars usually have specialized System on Chip with inbuilt DSP which does hardware decoding and rendering of video/audio thereby making the end user experience very smooth.
When booting up the system, the vehicle critical services partition is used which is very lightweight. This is responsible for starting up the other end user services like Tuner/Media/HVAC which reside on the other core.