[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] Machine specific option ROMs
From: |
BALATON Zoltan |
Subject: |
Re: [Qemu-devel] Machine specific option ROMs |
Date: |
Tue, 20 Aug 2019 01:42:59 +0200 (CEST) |
User-agent: |
Alpine 2.21.9999 (BSF 287 2018-06-16) |
On Mon, 19 Aug 2019, Gerd Hoffmann wrote:
> On Mon, Aug 19, 2019 at 02:38:09AM +0200, BALATON Zoltan wrote:
>> I know about the possibility to set the option ROM of a PCIDevice with the
>> romfile property (that we can set on command line or in a device's init
>> method) but is there a way to set it depending on the machine that uses the
>> device? If this is not currently possible what would be needed to allow
>> this?
>
> Should work with compat properties. That is a list of device, property
> and value which a specific machine type should use. Typically they are
> used to make versioned machine types behave simliar to older qemu
> versions (this is where the name comes from). Using them to use
> non-default properties on ppc platform should work too.
>
> For example in qemu 1.5 the nic roms got EFI support and there is a
> compat property which switches the pc-i440fx-1.4 (and older) machine
> types to the non-efi versions. Grep for pxe-e1000.rom to find the code.
OK thanks, looks like something like this works:
diff --git a/hw/ppc/mac_newworld.c b/hw/ppc/mac_newworld.c
index c5bbcc7433..8ee937e3ce 100644
--- a/hw/ppc/mac_newworld.c
+++ b/hw/ppc/mac_newworld.c
@@ -569,6 +572,10 @@ static int core99_kvm_type(MachineState *machine, const
char *arg)
return 2;
}
+static GlobalProperty compat[] = {
+ { "VGA", "romfile", NDRV_VGA_FILENAME },
+};
+
static void core99_machine_class_init(ObjectClass *oc, void *data)
{
MachineClass *mc = MACHINE_CLASS(oc);
@@ -587,6 +594,7 @@ static void core99_machine_class_init(ObjectClass *oc, void
*data)
mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("7400_v2.9");
#endif
mc->ignore_boot_device_suffixes = true;
+ compat_props_add(mc->compat_props, compat, G_N_ELEMENTS(compat));
fwc->get_dev_path = core99_fw_dev_path;
}
Mark, do you think this could replace the current way of passing this
driver via fw_cfg and would you accept patches to OpenBIOS to revert the
ndrv patching to replace that with this solution? (The vga_config_cb
already adds the driver from the ROM when set as above so no further hacks
are necessary. If we want we can keep the vga-ndrv? option to control this
adding NDRV from ROM after the current use of this setting is no longer
needed.) I think this would allow some simplification and also avoids
patching ati-vga with this driver without needing to add vga-ndrv?=false
manually. (In the future this same way can also be used to pass proper
FCode ROMs to OpenBIOS.)
Regards,
BALATON Zoltan