In the past, when the user blocked for an IRQ signal, the last signal was
acknowledged automatically thereby unmasking the IRQ. Now, the signal session
got a dedicated RPC for acknowledging IRQs and the HW back-end of that RPC
acknowledged the IRQ signal too. This led to the situation that IRQs were
unmasked twice. However, drivers expect an interrupt to be unmasked only on
the Irq_session::ack_irq and thus IRQ unmasking was moved from
Kernel::ack_signal to a dedicated kernel call.
Fixes#1493
In order to match the I/O APIC configuration, a request for user timer
IRQ 0 is remapped to vector 50 (Board::TIMER_VECTOR_USER), all other
requests are transposed by adding the vector offset 48
(Board::VECTOR_REMAP_BASE).
The generalization of interrupt objects in the kernel and the use of
C++ polymorphism instead of explicitely checking for special interrupts
within generic code (Cpu_job::_interrupt) enables the registration of
additional interrupts used by the kernel, which are needed for specific
aspects added to the kernel, like ARM hardware virtualization interrupts.
* Introduce generic base class for interrupt objects handled by the kernel
* Derive an interrupt class for those handled by the user-land
* Implement IPI-specific interrupt class
* Implement timer interrupts using the new generic base class
Ref #1405
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082
Martin Stein
Alexander Boettcher
Stefan Kalkowski
Reto Buerki
Norman Feske