Re: Problems with irq mapping in qemu v5.2

[BALATON Zoltan via <qemu-devel@nongnu.org>]

On Wed, 23 Dec 2020, Guenter Roeck wrote:
> On Thu, Dec 24, 2020 at 02:34:07AM +0100, BALATON Zoltan wrote:
> [ ... ]
>>
>> If we need legacy mode then we may be able to emulate that by setting BARs
>> to legacy ports ignoring what values are written to them if legacy mode
>> config is set (which may be what the real chip does) and we already have
>> IRQs hard wired to legacy values so that would give us legacy and
>> half-native mode which is enough for both fuloong2e and pegasos2 but I'm not
>> sure how can we fix BARs in QEMU because that's also handled by generic PCI
>> code which I also don't want to break.
>
> The code below works for booting Linux while at the same time not affecting
> any other emulation. I don't claim it to be a perfect fix, and overloading
> the existing property is a bit hackish, but it does work.

Yes, maybe combining it with my original patch 1 to change secondary to 
flags to make it a bit cleaner would work for me. Then we would either 
only emulate legacy or half-native mode which is sufficient for these two 
machines we have. If Mark or others do not object it this time, I can 
update my patch and resubmit with this one to fix this issue, otherwise 
let's wait what idea do they have because I hate to spend time with 
something only to be discarded again. I think we don't need more complete 
emulation of this chip than this for now but if somebody wants to attempt 
that I don't mind as long as it does not break pegasos2.

Regards,
BALATON Zoltan

> Guenter
>
> ---
> From cf2d1d655f3fe4f88dc435a3ac4e1e6b6040d08b Mon Sep 17 00:00:00 2001
> From: Guenter Roeck <linux@roeck-us.net>
> Date: Wed, 23 Dec 2020 09:12:37 -0800
> Subject: [PATCH] via-ide: Fix fuloong2 support
>
> Fuloong2 needs to use legacy mode for IDE support to work with Linux.
> Add property to via-ide driver to make the mode configurable, and set
> legacy mode for Fuloong2.
>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> hw/ide/via.c        | 16 ++++++++++++++--
> hw/mips/fuloong2e.c |  4 +++-
> 2 files changed, 17 insertions(+), 3 deletions(-)
>
> diff --git a/hw/ide/via.c b/hw/ide/via.c
> index be09912b33..9e55e717e8 100644
> --- a/hw/ide/via.c
> +++ b/hw/ide/via.c
> @@ -26,6 +26,7 @@
>
> #include "qemu/osdep.h"
> #include "hw/pci/pci.h"
> +#include "hw/qdev-properties.h"
> #include "migration/vmstate.h"
> #include "qemu/module.h"
> #include "sysemu/dma.h"
> @@ -185,12 +186,17 @@ static void via_ide_realize(PCIDevice *dev, Error **errp)
>                           &d->bus[1], "via-ide1-cmd", 4);
>     pci_register_bar(dev, 3, PCI_BASE_ADDRESS_SPACE_IO, &d->cmd_bar[1]);
>
> -    bmdma_setup_bar(d);
> -    pci_register_bar(dev, 4, PCI_BASE_ADDRESS_SPACE_IO, &d->bmdma_bar);
> +    if (!d->secondary) {
> +        bmdma_setup_bar(d);
> +        pci_register_bar(dev, 4, PCI_BASE_ADDRESS_SPACE_IO, &d->bmdma_bar);
> +    }
>
>     qdev_init_gpio_in(ds, via_ide_set_irq, 2);
>     for (i = 0; i < 2; i++) {
>         ide_bus_new(&d->bus[i], sizeof(d->bus[i]), ds, i, 2);
> +        if (d->secondary) {
> +            ide_init_ioport(&d->bus[i], NULL, i ? 0x170 : 0x1f0, i ? 0x376 : 0x3f6);
> +        }
>         ide_init2(&d->bus[i], qdev_get_gpio_in(ds, i));
>
>         bmdma_init(&d->bus[i], &d->bmdma[i], d);
> @@ -210,6 +216,11 @@ static void via_ide_exitfn(PCIDevice *dev)
>     }
> }
>
> +static Property via_ide_properties[] = {
> +    DEFINE_PROP_UINT32("legacy_mode", PCIIDEState, secondary, 0), /* hijacked */
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> static void via_ide_class_init(ObjectClass *klass, void *data)
> {
>     DeviceClass *dc = DEVICE_CLASS(klass);
> @@ -223,6 +234,7 @@ static void via_ide_class_init(ObjectClass *klass, void *data)
>     k->device_id = PCI_DEVICE_ID_VIA_IDE;
>     k->revision = 0x06;
>     k->class_id = PCI_CLASS_STORAGE_IDE;
> +    device_class_set_props(dc, via_ide_properties);
>     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
> }
>
> diff --git a/hw/mips/fuloong2e.c b/hw/mips/fuloong2e.c
> index 23c526c69d..d0398d6266 100644
> --- a/hw/mips/fuloong2e.c
> +++ b/hw/mips/fuloong2e.c
> @@ -245,7 +245,9 @@ static void vt82c686b_southbridge_init(PCIBus *pci_bus, int slot, qemu_irq intc,
>     /* Super I/O */
>     isa_create_simple(isa_bus, TYPE_VT82C686B_SUPERIO);
>
> -    dev = pci_create_simple(pci_bus, PCI_DEVFN(slot, 1), "via-ide");
> +    dev = pci_new(PCI_DEVFN(slot, 1), "via-ide");
> +    qdev_prop_set_uint32(&dev->qdev, "legacy_mode", 1);
> +    pci_realize_and_unref(dev, pci_bus, &error_fatal);
>     pci_ide_create_devs(dev);
>
>     pci_create_simple(pci_bus, PCI_DEVFN(slot, 2), "vt82c686b-usb-uhci");
>