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X-Received-From: 2607:f8b0:4864:20::343 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Corey Minyard , "Michael S. Tsirkin" , Jason Wang , Mark Cave-Ayland , qemu-devel , KONRAD Frederic , "Edgar E. Iglesias" , Paul Burton , Aleksandar Rikalo , Magnus Damm , =?UTF-8?Q?Herv=C3=A9_Poussineau?= , =?UTF-8?B?TWFyYy1BbmRyw6kgTHVyZWF1?= , Artyom Tarasenko , Eduardo Habkost , Fabien Chouteau , qemu-arm , Richard Henderson , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= , qemu-ppc , Aleksandar Markovic , Paolo Bonzini , Aurelien Jarno Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 24 Oct 2019 at 12:48, Philippe Mathieu-Daud=C3=A9 wrote: > Just wondering, if we had a "bus_address" property to the abstract > SysBus class (and eventually "bus_name" for later) we could create/map > sysbus devices from command line? I don't think this is a good plan -- users shouldn't have to know about the memory map of their boards. Plus it doesn't deal with the complications of multiple address spaces, DMA, wiring up irq lines to an interrupt controller, SoC reset handling, clocks, power-managment... Command line -device was designed for pluggable devices, where in the world of real hardware the device can be physically plugged and unplugged and there's a clear interface that can be modelled. You can't add an extra UART to an embedded board in real hardware either. The only plausible argument I've seen for command-line plugging of embedded devices is as a sort of side-effect of having a configuration language syntax for them for the purpose of being able to write board models as data-driven config files rather than in C code. But that would be a lot of design and engineering work, and if we want that I think we should approach it forwards, not arrive at it backwards by adding gradual tweaks like 'address' properties to devices. thanks -- PMM