Hi everyone, I'm always trying to configure the timer for my Zedboard and the system clock doesn't advance. I checked this in the Timer::system_clock() function In order to construct my timer driver, I use mptimer option, so I configured the private timer of my board in the file timer-arm-mptimer.cpp. Private Timers call the function interval() which use the global timer of the board (bsp/zynq/ timer-arm-mptimer-zynq.cpp file) Here is a part of the implementation of my global timer (I just launch counter) : Mmio_register_block t(Kmem::mmio_remap(Mem_layout::Gpt_phys_base)); t.write<Mword>(0, GPT_CR); t.write<Mword>(0, GPT_CNT0); t.write<Mword>(0, GPT_CNT1); t.modify<Mword>(GPT_CR_EN, 0, GPT_CR); Mword vc = start_as_counter(); while (t.read<Mword>(GPT_CNT0) < Gpt_ticks) ; Mword interval = (vc - stop_counter()) / Ticks; t.write<Mword>(0, GPT_CR); return interval; The private timers are bind to the GIC with the IRQ 27, so I mentioned this value in the static unsigned irq() function. GIC is initialized in the bsp/zynq/pic-arm-zynq.cpp file (similar to the iMX6 architecture) Pic::init() { typedef Irq_mgr_multi_chip<Gic_sz> M; M *m = new Boot_object<M>(1); gic.construct(Kmem::mmio_remap(Mem_layout::Gic_cpu_phys_base), Kmem::mmio_remap(Mem_layout::Gic_dist_phys_base)); m->add_chip(0, gic, gic->nr_irqs()); Irq_mgr::mgr = m; } To finish I saw timer_tick class. It seems to be a good way to update system clock because there are interrupts handler which call the update_system_clock function. So I added a call to the Timer_tick::setup() function in my startup-arm.cpp file after timer initialization. But when I boot the sytem I obtain the following message Panic - Could not allocate scheduling IRQ 27 The origin of this problem is the allocate_irq() function So do I have to modify something in my IRQ manager or did I forget one step during the construction of my timer driver ? Thanks in advance Best regards, Xavier Le Bars