diff options
Diffstat (limited to 'roms/SLOF/lib/libvirtio/virtio-scsi.c')
| -rw-r--r-- | roms/SLOF/lib/libvirtio/virtio-scsi.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/roms/SLOF/lib/libvirtio/virtio-scsi.c b/roms/SLOF/lib/libvirtio/virtio-scsi.c new file mode 100644 index 000000000..96285e389 --- /dev/null +++ b/roms/SLOF/lib/libvirtio/virtio-scsi.c @@ -0,0 +1,152 @@ +/****************************************************************************** + * Copyright (c) 2012 IBM Corporation + * All rights reserved. + * This program and the accompanying materials + * are made available under the terms of the BSD License + * which accompanies this distribution, and is available at + * http://www.opensource.org/licenses/bsd-license.php + * + * Contributors: + * IBM Corporation - initial implementation + *****************************************************************************/ + +#include <stdio.h> +#include <string.h> +#include <cpu.h> +#include <helpers.h> +#include "virtio.h" +#include "virtio-internal.h" +#include "virtio-scsi.h" + +int virtioscsi_send(struct virtio_device *dev, + struct virtio_scsi_req_cmd *req, + struct virtio_scsi_resp_cmd *resp, + int is_read, void *buf, uint64_t buf_len) +{ + + volatile uint16_t *current_used_idx; + uint16_t last_used_idx, avail_idx; + int id; + uint32_t time; + struct vqs *vq = &dev->vq[VIRTIO_SCSI_REQUEST_VQ]; + + avail_idx = virtio_modern16_to_cpu(dev, vq->avail->idx); + + last_used_idx = vq->used->idx; + current_used_idx = &vq->used->idx; + + /* Determine descriptor index */ + id = (avail_idx * 3) % vq->size; + virtio_fill_desc(vq, id, dev->features, (uint64_t)req, sizeof(*req), VRING_DESC_F_NEXT, + id + 1); + + if (buf == NULL || buf_len == 0) { + /* Set up descriptor for response information */ + virtio_fill_desc(vq, id + 1, dev->features, + (uint64_t)resp, sizeof(*resp), + VRING_DESC_F_WRITE, 0); + } else if (is_read) { + /* Set up descriptor for response information */ + virtio_fill_desc(vq, id + 1, dev->features, + (uint64_t)resp, sizeof(*resp), + VRING_DESC_F_NEXT | VRING_DESC_F_WRITE, + id + 2); + /* Set up virtqueue descriptor for data from device */ + virtio_fill_desc(vq, id + 2, dev->features, + (uint64_t)buf, buf_len, VRING_DESC_F_WRITE, 0); + } else { + /* Set up virtqueue descriptor for data to device */ + virtio_fill_desc(vq, id + 1, dev->features, + (uint64_t)buf, buf_len, VRING_DESC_F_NEXT, + id + 2); + /* Set up descriptor for response information */ + virtio_fill_desc(vq, id + 2, dev->features, + (uint64_t)resp, sizeof(*resp), + VRING_DESC_F_WRITE, 0); + } + + vq->avail->ring[avail_idx % vq->size] = virtio_cpu_to_modern16(dev, id); + mb(); + vq->avail->idx = virtio_cpu_to_modern16(dev, avail_idx + 1); + + /* Tell HV that the vq is ready */ + virtio_queue_notify(dev, VIRTIO_SCSI_REQUEST_VQ); + + /* Wait for host to consume the descriptor */ + time = SLOF_GetTimer() + VIRTIO_TIMEOUT; + while (*current_used_idx == last_used_idx) { + // do something better + mb(); + if (time < SLOF_GetTimer()) + break; + } + + virtio_free_desc(vq, id, dev->features); + virtio_free_desc(vq, id + 1, dev->features); + if (!(buf == NULL || buf_len == 0)) + virtio_free_desc(vq, id + 2, dev->features); + + return 0; +} + +/** + * Initialize virtio-block device. + * @param dev pointer to virtio device information + */ +int virtioscsi_init(struct virtio_device *dev) +{ + struct vqs *vq_ctrl, *vq_event, *vq_request; + int status = VIRTIO_STAT_ACKNOWLEDGE; + + /* Reset device */ + // XXX That will clear the virtq base. We need to move + // initializing it to here anyway + // + // virtio_reset_device(dev); + + /* Acknowledge device. */ + virtio_set_status(dev, status); + + /* Tell HV that we know how to drive the device. */ + status |= VIRTIO_STAT_DRIVER; + virtio_set_status(dev, status); + + /* Device specific setup - we do not support special features right now */ + if (dev->features & VIRTIO_F_VERSION_1) { + if (virtio_negotiate_guest_features(dev, VIRTIO_F_VERSION_1)) + goto dev_error; + virtio_get_status(dev, &status); + } else { + virtio_set_guest_features(dev, 0); + } + + vq_ctrl = virtio_queue_init_vq(dev, VIRTIO_SCSI_CONTROL_VQ); + vq_event = virtio_queue_init_vq(dev, VIRTIO_SCSI_EVENT_VQ); + vq_request = virtio_queue_init_vq(dev, VIRTIO_SCSI_REQUEST_VQ); + if (!vq_ctrl || !vq_event || !vq_request) + goto dev_error; + + /* Tell HV that setup succeeded */ + status |= VIRTIO_STAT_DRIVER_OK; + virtio_set_status(dev, status); + + return 0; +dev_error: + printf("%s: failed\n", __func__); + status |= VIRTIO_STAT_FAILED; + virtio_set_status(dev, status); + return -1; +} + +/** + * Shutdown the virtio-block device. + * @param dev pointer to virtio device information + */ +void virtioscsi_shutdown(struct virtio_device *dev) +{ + /* Quiesce device */ + virtio_set_status(dev, VIRTIO_STAT_FAILED); + + /* Reset device */ + virtio_reset_device(dev); +} |