Re: [Qemu-devel] [PATCH 1/5] i8259: qdev-ify creation

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-01-12 08:58, Alexander Graf wrote:
> 
> On 12.01.2012, at 08:35, Jan Kiszka wrote:
> 
>> On 2012-01-12 01:04, Andreas Färber wrote:
>>> Alex,
>>>
>>> I have this in my mailbox, but I'm still waiting for an SoB. Hervé?
>>>
>>> Regards,
>>> Andreas
>>>
>>> -------- Original-Nachricht --------
>>> Betreff: [PATCH 1/5] i8259: qdev-ify creation
>>> Datum: Sun, 26 Jun 2011 14:47:09 +0200
>>> Von: Hervé Poussineau <hpoussin@reactos.org>
>>> An: andreas.faerber@web.de
>>> Kopie (CC): Hervé Poussineau <hpoussin@reactos.org>
>>>
>>> ---
>>> hw/i8259.c |   53 +++++++++++++++++++++++++++++++++++++++++++++++++----
>>> 1 files changed, 49 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/hw/i8259.c b/hw/i8259.c
>>> index 84d330d..59e8bd6 100644
>>> --- a/hw/i8259.c
>>> +++ b/hw/i8259.c
>>> @@ -26,6 +26,7 @@
>>> #include "isa.h"
>>> #include "monitor.h"
>>> #include "qemu-timer.h"
>>> +#include "sysbus.h"
>>>
>>> /* debug PIC */
>>> //#define DEBUG_PIC
>>> @@ -524,16 +525,60 @@ void irq_info(Monitor *mon)
>>>
>>> qemu_irq *i8259_init(qemu_irq parent_irq)
>>> {
>>> -    PicState2 *s;
>>> +    DeviceState *dev;
>>> +    dev = qdev_create(NULL, "i8259");
>>> +    qdev_init_nofail(dev);
>>> +    qdev_connect_gpio_out(dev, 0, parent_irq);
>>> +
>>> +    return dev->gpio_in;
>>> +}
>>> +
>>> +typedef struct SysBusPicState2 {
>>> +    SysBusDevice busdev;
>>> +    PicState2 state;
>>> +} SysBusPicState2;
>>> +
>>> +static void i8259_set_irq_sysbus(void *opaque, int line, int level)
>>> +{
>>> +    SysBusPicState2 *sysbus = opaque;
>>> +    PicState2 *s = &sysbus->state;
>>> +    i8259_set_irq(s, line, level);
>>> +}
>>> +
>>> +static int i8259_sysbus_init(SysBusDevice *dev)
>>> +{
>>> +    SysBusPicState2 *sysbus = FROM_SYSBUS(SysBusPicState2, dev);
>>> +    PicState2 *s = &sysbus->state;
>>> +
>>> +    if (isa_pic) {
>>> +        return 1;
>>> +    }
>>>
>>> -    s = qemu_mallocz(sizeof(PicState2));
>>>     pic_init1(0x20, 0x4d0, &s->pics[0]);
>>>     pic_init1(0xa0, 0x4d1, &s->pics[1]);
>>>     s->pics[0].elcr_mask = 0xf8;
>>>     s->pics[1].elcr_mask = 0xde;
>>> -    s->parent_irq = parent_irq;
>>>     s->pics[0].pics_state = s;
>>>     s->pics[1].pics_state = s;
>>>     isa_pic = s;
>>> -    return qemu_allocate_irqs(i8259_set_irq, s, 16);
>>> +
>>> +    qdev_init_gpio_in(&dev->qdev, i8259_set_irq_sysbus, 16);
>>> +    qdev_init_gpio_out(&dev->qdev, &s->parent_irq, 1);
>>> +    return 0;
>>> +}
>>> +
>>> +static SysBusDeviceInfo i8259_sysbus_info = {
>>> +    .qdev.name = "i8259",
>>> +    .qdev.size = sizeof(SysBusPicState2),
>>> +    .init = i8259_sysbus_init,
>>> +    .qdev.props = (Property[]) {
>>> +        DEFINE_PROP_END_OF_LIST()
>>> +    },
>>> +};
>>> +
>>> +static void i8259_register_devices(void)
>>> +{
>>> +   sysbus_register_withprop(&i8259_sysbus_info);
>>> }
>>> +
>>> +device_init(i8259_register_devices)
>>
>> This is obsolete. The i8259 has been significantly refactored (into two
>> ISA devices) and qdev'ified some moons ago.
> 
> The reason we were discussing this was a circular dependency on PREP.
> 
> The PIC is sitting on the ISA bus.
> The ISA bus is behind a PCI-ISA bridge
> the PCI-ISA bridge is behind a PCI host controller
> the PCI host controller needs interrupt lines in its initialization which are attached to the PIC
> 
> Any good ideas on how to resolve this? :)

As we do this always: Split up initialization and IRQ line wiring.

Jan

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