vfio/igd: Allow overriding GMS with 0xf0 to 0xfe on Gen9+

On Gen9 and later IGD devices, GMS 0xf0 to 0xfe represents 4MB to 60MB
pre-allocated memory size in 4MB increments. Allow users overriding
GMS with these values.

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
Reviewed-by: Corvin Köhne <c.koehne@beckhoff.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250505170305.23622-8-tomitamoeko@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
This commit is contained in:
Tomita Moeko 2025-05-06 01:03:03 +08:00 committed by Cédric Le Goater
parent 16cbb43302
commit 395a1f7941

View file

@ -412,6 +412,44 @@ static bool vfio_pci_igd_setup_lpc_bridge(VFIOPCIDevice *vdev, Error **errp)
return true; return true;
} }
static bool vfio_pci_igd_override_gms(int gen, uint32_t gms, uint32_t *gmch)
{
bool ret = false;
if (gen == -1) {
error_report("x-igd-gms is not supported on this device");
} else if (gen < 8) {
if (gms <= 0x10) {
*gmch &= ~(IGD_GMCH_GEN6_GMS_MASK << IGD_GMCH_GEN6_GMS_SHIFT);
*gmch |= gms << IGD_GMCH_GEN6_GMS_SHIFT;
ret = true;
} else {
error_report(QERR_INVALID_PARAMETER_VALUE, "x-igd-gms", "0~0x10");
}
} else if (gen == 8) {
if (gms <= 0x40) {
*gmch &= ~(IGD_GMCH_GEN8_GMS_MASK << IGD_GMCH_GEN8_GMS_SHIFT);
*gmch |= gms << IGD_GMCH_GEN8_GMS_SHIFT;
ret = true;
} else {
error_report(QERR_INVALID_PARAMETER_VALUE, "x-igd-gms", "0~0x40");
}
} else {
/* 0x0 to 0x40: 32MB increments starting at 0MB */
/* 0xf0 to 0xfe: 4MB increments starting at 4MB */
if ((gms <= 0x40) || (gms >= 0xf0 && gms <= 0xfe)) {
*gmch &= ~(IGD_GMCH_GEN8_GMS_MASK << IGD_GMCH_GEN8_GMS_SHIFT);
*gmch |= gms << IGD_GMCH_GEN8_GMS_SHIFT;
ret = true;
} else {
error_report(QERR_INVALID_PARAMETER_VALUE,
"x-igd-gms", "0~0x40 or 0xf0~0xfe");
}
}
return ret;
}
#define IGD_GGC_MMIO_OFFSET 0x108040 #define IGD_GGC_MMIO_OFFSET 0x108040
#define IGD_BDSM_MMIO_OFFSET 0x1080C0 #define IGD_BDSM_MMIO_OFFSET 0x1080C0
@ -594,24 +632,9 @@ static bool vfio_pci_igd_config_quirk(VFIOPCIDevice *vdev, Error **errp)
* 32MiB. This option should only be used when the desired size cannot be * 32MiB. This option should only be used when the desired size cannot be
* set from DVMT Pre-Allocated option in host BIOS. * set from DVMT Pre-Allocated option in host BIOS.
*/ */
if (vdev->igd_gms) { if (vdev->igd_gms &&
if (gen < 8) { !vfio_pci_igd_override_gms(gen, vdev->igd_gms, &gmch)) {
if (vdev->igd_gms <= 0x10) { return false;
gmch &= ~(IGD_GMCH_GEN6_GMS_MASK << IGD_GMCH_GEN6_GMS_SHIFT);
gmch |= vdev->igd_gms << IGD_GMCH_GEN6_GMS_SHIFT;
} else {
error_report(QERR_INVALID_PARAMETER_VALUE,
"x-igd-gms", "0~0x10");
}
} else {
if (vdev->igd_gms <= 0x40) {
gmch &= ~(IGD_GMCH_GEN8_GMS_MASK << IGD_GMCH_GEN8_GMS_SHIFT);
gmch |= vdev->igd_gms << IGD_GMCH_GEN8_GMS_SHIFT;
} else {
error_report(QERR_INVALID_PARAMETER_VALUE,
"x-igd-gms", "0~0x40");
}
}
} }
gms_size = igd_stolen_memory_size(gen, gmch); gms_size = igd_stolen_memory_size(gen, gmch);