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pc-bios/s390-ccw/virtio: Set missing status bits while initializing

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According chapter "3.1.1 Driver Requirements: Device Initialization"
of the Virtio specification (v1.1), a driver for a device has to set
the ACKNOWLEDGE and DRIVER bits in the status field after resetting
the device. The s390-ccw bios skipped these steps so far and seems
like QEMU never cared. Anyway, it's better to follow the spec, so
let's set these bits now in the right spots, too.

Message-Id: <20220704111903.62400-7-thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This commit is contained in:
Thomas Huth 2022-07-04 13:18:57 +02:00
parent 5447de2619
commit 175aa06a15
1 changed files with 14 additions and 4 deletions
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18
pc-bios/s390-ccw/virtio.c
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@ -220,7 +220,7 @@ int virtio_run(VDev *vdev, int vqid, VirtioCmd *cmd)
void virtio_setup_ccw(VDev *vdev)
{
int i, rc, cfg_size = 0;
unsigned char status = VIRTIO_CONFIG_S_DRIVER_OK;
uint8_t status;
struct VirtioFeatureDesc {
uint32_t features;
uint8_t index;
@ -234,6 +234,10 @@ void virtio_setup_ccw(VDev *vdev)
run_ccw(vdev, CCW_CMD_VDEV_RESET, NULL, 0, false);
status = VIRTIO_CONFIG_S_ACKNOWLEDGE;
rc = run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status), false);
IPL_assert(rc == 0, "Could not write ACKNOWLEDGE status to host");
switch (vdev->senseid.cu_model) {
case VIRTIO_ID_NET:
vdev->nr_vqs = 2;
@ -253,6 +257,11 @@ void virtio_setup_ccw(VDev *vdev)
default:
panic("Unsupported virtio device\n");
}
status |= VIRTIO_CONFIG_S_DRIVER;
rc = run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status), false);
IPL_assert(rc == 0, "Could not write DRIVER status to host");
IPL_assert(
run_ccw(vdev, CCW_CMD_READ_CONF, &vdev->config, cfg_size, false) == 0,
"Could not get block device configuration");
@ -291,9 +300,10 @@ void virtio_setup_ccw(VDev *vdev)
run_ccw(vdev, CCW_CMD_SET_VQ, &info, sizeof(info), false) == 0,
"Cannot set VQ info");
}
IPL_assert(
run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status), false) == 0,
"Could not write status to host");
status |= VIRTIO_CONFIG_S_DRIVER_OK;
rc = run_ccw(vdev, CCW_CMD_WRITE_STATUS, &status, sizeof(status), false);
IPL_assert(rc == 0, "Could not write DRIVER_OK status to host");
}
bool virtio_is_supported(SubChannelId schid)