On Mon, Jan 19, 2015 at 09:43:56AM +0000, Marc Zyngier wrote: > Tegra's LIC (Legacy Interrupt Controller) has been so far only > supported as a weird extension of the GIC, which is not exactly > pretty. > > The stacked IRQ domain framework fits this pretty well, and allows > the LIC code to be turned into a standalone irqchip. In the process, > make the driver DT aware, something that was sorely missing from > the mach-tegra implementation. > Note that the GIC isn't really stacked on top of the LIC. Each IRQ is presented to both the LIC and the GIC (as an SPI). The LIC is only used to wakeup the CPU in case the GIC is not powered. The LIC can also generate interrupts towards the AVP/ARM7, but that's outside the scope of Linux ofcourse. The LIC can also be used to force an IRQ and that forced IRQ will be propagated to the GIC. (see also figure 2, page 36 of the Tegra K1 TRM) Cheers, Peter. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
