Re: [PATCH v5 11/11] hw/isa/vt82c686: Implement relocation and toggling of SuperI/O functions

[Philippe Mathieu-Daudé]

On 14/1/24 13:39, Bernhard Beschow wrote:
> The VIA south bridges are able to relocate and toggle (enable or disable) their
> SuperI/O functions. So far this is hardcoded such that all functions are always
> enabled and are located at fixed addresses.
>
> Some PC BIOSes seem to probe for I/O occupancy before activating such a function
> and issue an error in case of a conflict. Since the functions are currently
> enabled on reset, conflicts are always detected. Prevent that by implementing
> relocation and toggling of the SuperI/O functions.
>
> Note that all SuperI/O functions are now deactivated upon reset (except for
> VT82C686B's serial ports where Fuloong 2e's rescue-yl seems to expect them to be
> enabled by default). Rely on firmware to configure the functions accordingly.
>
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
> ---
>   hw/isa/vt82c686.c | 65 +++++++++++++++++++++++++++++++++++++++--------
>   1 file changed, 55 insertions(+), 10 deletions(-)


> +static void via_superio_devices_enable(ViaSuperIOState *s, uint8_t data)
> +{
> +    ISASuperIOClass *ic = ISA_SUPERIO_GET_CLASS(s);
> +

       memory_region_transaction_begin();

> +    isa_parallel_set_enabled(s->superio.parallel[0], (data & 0x3) != 3);
> +    for (int i = 0; i < ic->serial.count; i++) {
> +        isa_serial_set_enabled(s->superio.serial[i], data & BIT(i + 2));
> +    }
> +    isa_fdc_set_enabled(s->superio.floppy, data & BIT(4));

       memory_region_transaction_commit();

> +}
> +