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Oleksandr Tyshchenko
5d752df85f
This patch adds ability to the device emulator to notify otherend (some entity running in the guest) using a SPI and implements Arm specific bits for it. Proposed interface allows emulator to set the logical level of a one of a domain's IRQ lines. We can't reuse the existing DM op (xen_dm_op_set_isa_irq_level) to inject an interrupt as the "isa_irq" field is only 8-bit and able to cover IRQ 0 - 255, whereas we need a wider range (0 - 1020). Please note, for egde-triggered interrupt (which is used for the virtio-mmio emulation) we only trigger the interrupt on Arm if the level is asserted (rising edge) and do nothing if the level is deasserted (falling edge), so the call could be named "trigger_irq" (without the level parameter). But, in order to model the line closely (to be able to support level-triggered interrupt) we need to know whether the line is low or high, so the proposed interface has been chosen. However, it is worth mentioning that in case of the level-triggered interrupt, we should keep injecting the interrupt to the guest until the line is deasserted (this is not covered by current patch). Signed-off-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Acked-by: Stefano Stabellini <sstabellini@kernel.org> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com> [On Arm only] Tested-by: Wei Chen <Wei.Chen@arm.com>