Re: [Qemu-devel] [PATCH v2 1/6] Use IO port for qemu<->guest BIOS communication.

[Anthony Liguori <anthony@codemonkey.ws>]

Gleb Natapov wrote:
> Use PIO to get configuration info between qemu process and guest BIOS.
>
> Signed-off-by: Gleb Natapov <gleb@qumranet.com>
> ---
>
>  hw/pc.c |   59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 59 insertions(+), 0 deletions(-)
>
> diff --git a/hw/pc.c b/hw/pc.c
> index 213ead8..8caa48f 100644
> --- a/hw/pc.c
> +++ b/hw/pc.c
> @@ -44,6 +44,7 @@
>  
>  /* Leave a chunk of memory at the top of RAM for the BIOS ACPI tables.  */
>  #define ACPI_DATA_SIZE       0x10000
> +#define BIOS_CFG_IOPORT 0x1234
>  
>  #define MAX_IDE_BUS 2
>  
> @@ -53,6 +54,26 @@ static PITState *pit;
>  static IOAPICState *ioapic;
>  static PCIDevice *i440fx_state;
>  
> +typedef struct _BIOSCfgEntry {
> +    uint16_t len;
> +    uint8_t *data;
> +} BIOSCfgEntry;
>   

So why aren't we using the ROM mechanism suggested by Blue Swirl?  
Unless we're switching other firmwares to use this mechanism, I think it 
would be better to have a single QEMU<->firmware interface that we could 
support for all architectures.

Regards,

Anthony Liguori