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authorMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>2022-03-05 15:09:56 +0000
committerMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>2022-03-09 09:28:28 +0000
commitb793b4ef8c862891c716cd163aaa7e4af0d697da (patch)
tree1e67cac8ca64381fe32c6146edf09756cfa0f4ff /hw/m68k
parent677a4725b1c49b139b00d8eaa932676ed8620931 (diff)
mos6522: implement edge-triggering for CA1/2 and CB1/2 control line IRQs
The mos6522 datasheet describes how the control lines IRQs are edge-triggered according to the configuration in the PCR register. Implement the logic according to the datasheet so that the interrupt bits in IFR are latched when the edge is detected, and cleared when reading portA/portB or writing to IFR as necessary. To maintain bisectibility this change also updates the SCSI, SCSI data, Nubus and VIA2 60Hz/1Hz clocks in the q800 machine to be negative edge-triggered as confirmed by the PCR programming in all of Linux, NetBSD and MacOS. Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Reviewed-by: Laurent Vivier <laurent@vivier.eu> Message-Id: <20220305150957.5053-12-mark.cave-ayland@ilande.co.uk> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Diffstat (limited to 'hw/m68k')
-rw-r--r--hw/m68k/q800.c9
1 files changed, 5 insertions, 4 deletions
diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index 55dfe5036f..66ca5c0df6 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -533,10 +533,11 @@ static void q800_init(MachineState *machine)
sysbus = SYS_BUS_DEVICE(dev);
sysbus_realize_and_unref(sysbus, &error_fatal);
- sysbus_connect_irq(sysbus, 0, qdev_get_gpio_in(via2_dev,
- VIA2_IRQ_SCSI_BIT));
- sysbus_connect_irq(sysbus, 1, qdev_get_gpio_in(via2_dev,
- VIA2_IRQ_SCSI_DATA_BIT));
+ /* SCSI and SCSI data IRQs are negative edge triggered */
+ sysbus_connect_irq(sysbus, 0, qemu_irq_invert(qdev_get_gpio_in(via2_dev,
+ VIA2_IRQ_SCSI_BIT)));
+ sysbus_connect_irq(sysbus, 1, qemu_irq_invert(qdev_get_gpio_in(via2_dev,
+ VIA2_IRQ_SCSI_DATA_BIT)));
sysbus_mmio_map(sysbus, 0, ESP_BASE);
sysbus_mmio_map(sysbus, 1, ESP_PDMA);