@@ -516,13 +516,18 @@ static void mps2tz_common_init(MachineState *machine)
*/
memory_region_add_subregion(system_memory, 0x80000000, machine->ram);
- /* The overflow IRQs for all UARTs are ORed together.
+ /*
+ * The overflow IRQs for all UARTs are ORed together.
* Tx, Rx and "combined" IRQs are sent to the NVIC separately.
- * Create the OR gate for this.
+ * Create the OR gate for this: it has one input for the TX overflow
+ * and one for the RX overflow for each UART we might have.
+ * (If the board has fewer than the maximum possible number of UARTs
+ * those inputs are never wired up and are treated as always-zero.)
*/
object_initialize_child(OBJECT(mms), "uart-irq-orgate",
&mms->uart_irq_orgate, TYPE_OR_IRQ);
- object_property_set_int(OBJECT(&mms->uart_irq_orgate), "num-lines", 10,
+ object_property_set_int(OBJECT(&mms->uart_irq_orgate), "num-lines",
+ 2 * ARRAY_SIZE(mms->uart),
&error_fatal);
qdev_realize(DEVICE(&mms->uart_irq_orgate), NULL, &error_fatal);
qdev_connect_gpio_out(DEVICE(&mms->uart_irq_orgate), 0,
We create an OR gate to wire together the overflow IRQs for all the UARTs on the board; this has to have twice the number of inputs as there are UARTs, since each UART feeds it a TX overflow and an RX overflow interrupt line. Replace the hardcoded '10' with a calculation based on the size of the uart[] array in the MPS2TZMachineState. (We rely on OR gate inputs that are never wired up or asserted being treated as always-zero.) Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- hw/arm/mps2-tz.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)