linux-stable/drivers/scsi/snic/vnic_wq.c
Narsimhulu Musini c8806b6c9e snic: driver for Cisco SCSI HBA
Cisco has developed a new PCI HBA interface called sNIC, which stands for
SCSI NIC. This is a new storage feature supported on specialized network
adapter. The new PCI function provides a uniform host interface and abstracts
backend storage.

[jejb: fix up checkpatch errors]
Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-06-19 16:57:51 -07:00

237 lines
5.5 KiB
C

/*
* Copyright 2014 Cisco Systems, Inc. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include "vnic_dev.h"
#include "vnic_wq.h"
static inline int vnic_wq_get_ctrl(struct vnic_dev *vdev, struct vnic_wq *wq,
unsigned int index, enum vnic_res_type res_type)
{
wq->ctrl = svnic_dev_get_res(vdev, res_type, index);
if (!wq->ctrl)
return -EINVAL;
return 0;
}
static inline int vnic_wq_alloc_ring(struct vnic_dev *vdev, struct vnic_wq *wq,
unsigned int index, unsigned int desc_count, unsigned int desc_size)
{
return svnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count,
desc_size);
}
static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
{
struct vnic_wq_buf *buf;
unsigned int i, j, count = wq->ring.desc_count;
unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
for (i = 0; i < blks; i++) {
wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
if (!wq->bufs[i]) {
pr_err("Failed to alloc wq_bufs\n");
return -ENOMEM;
}
}
for (i = 0; i < blks; i++) {
buf = wq->bufs[i];
for (j = 0; j < VNIC_WQ_BUF_DFLT_BLK_ENTRIES; j++) {
buf->index = i * VNIC_WQ_BUF_DFLT_BLK_ENTRIES + j;
buf->desc = (u8 *)wq->ring.descs +
wq->ring.desc_size * buf->index;
if (buf->index + 1 == count) {
buf->next = wq->bufs[0];
break;
} else if (j + 1 == VNIC_WQ_BUF_DFLT_BLK_ENTRIES) {
buf->next = wq->bufs[i + 1];
} else {
buf->next = buf + 1;
buf++;
}
}
}
wq->to_use = wq->to_clean = wq->bufs[0];
return 0;
}
void svnic_wq_free(struct vnic_wq *wq)
{
struct vnic_dev *vdev;
unsigned int i;
vdev = wq->vdev;
svnic_dev_free_desc_ring(vdev, &wq->ring);
for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
kfree(wq->bufs[i]);
wq->bufs[i] = NULL;
}
wq->ctrl = NULL;
}
int vnic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
unsigned int desc_count, unsigned int desc_size)
{
int err;
wq->index = 0;
wq->vdev = vdev;
err = vnic_wq_get_ctrl(vdev, wq, 0, RES_TYPE_DEVCMD2);
if (err) {
pr_err("Failed to get devcmd2 resource\n");
return err;
}
svnic_wq_disable(wq);
err = vnic_wq_alloc_ring(vdev, wq, 0, desc_count, desc_size);
if (err)
return err;
return 0;
}
int svnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
unsigned int index, unsigned int desc_count, unsigned int desc_size)
{
int err;
wq->index = index;
wq->vdev = vdev;
err = vnic_wq_get_ctrl(vdev, wq, index, RES_TYPE_WQ);
if (err) {
pr_err("Failed to hook WQ[%d] resource\n", index);
return err;
}
svnic_wq_disable(wq);
err = vnic_wq_alloc_ring(vdev, wq, index, desc_count, desc_size);
if (err)
return err;
err = vnic_wq_alloc_bufs(wq);
if (err) {
svnic_wq_free(wq);
return err;
}
return 0;
}
void vnic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
unsigned int fetch_index, unsigned int posted_index,
unsigned int error_interrupt_enable,
unsigned int error_interrupt_offset)
{
u64 paddr;
unsigned int count = wq->ring.desc_count;
paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
writeq(paddr, &wq->ctrl->ring_base);
iowrite32(count, &wq->ctrl->ring_size);
iowrite32(fetch_index, &wq->ctrl->fetch_index);
iowrite32(posted_index, &wq->ctrl->posted_index);
iowrite32(cq_index, &wq->ctrl->cq_index);
iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
iowrite32(0, &wq->ctrl->error_status);
wq->to_use = wq->to_clean =
&wq->bufs[fetch_index / VNIC_WQ_BUF_BLK_ENTRIES(count)]
[fetch_index % VNIC_WQ_BUF_BLK_ENTRIES(count)];
}
void svnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
unsigned int error_interrupt_enable,
unsigned int error_interrupt_offset)
{
vnic_wq_init_start(wq, cq_index, 0, 0, error_interrupt_enable,
error_interrupt_offset);
}
unsigned int svnic_wq_error_status(struct vnic_wq *wq)
{
return ioread32(&wq->ctrl->error_status);
}
void svnic_wq_enable(struct vnic_wq *wq)
{
iowrite32(1, &wq->ctrl->enable);
}
int svnic_wq_disable(struct vnic_wq *wq)
{
unsigned int wait;
iowrite32(0, &wq->ctrl->enable);
/* Wait for HW to ACK disable request */
for (wait = 0; wait < 100; wait++) {
if (!(ioread32(&wq->ctrl->running)))
return 0;
udelay(1);
}
pr_err("Failed to disable WQ[%d]\n", wq->index);
return -ETIMEDOUT;
}
void svnic_wq_clean(struct vnic_wq *wq,
void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
{
struct vnic_wq_buf *buf;
BUG_ON(ioread32(&wq->ctrl->enable));
buf = wq->to_clean;
while (svnic_wq_desc_used(wq) > 0) {
(*buf_clean)(wq, buf);
buf = wq->to_clean = buf->next;
wq->ring.desc_avail++;
}
wq->to_use = wq->to_clean = wq->bufs[0];
iowrite32(0, &wq->ctrl->fetch_index);
iowrite32(0, &wq->ctrl->posted_index);
iowrite32(0, &wq->ctrl->error_status);
svnic_dev_clear_desc_ring(&wq->ring);
}