kernel-ark/drivers/net/enic/vnic_rq.h
Scott Feldman 4badc385d1 enic: workaround A0 erratum
A0 revision ASIC has an erratum on the RQ desc cache on chip where the
cache can become corrupted causing pkt buf writes to wrong locations.  The s/w
workaround is to post a dummy RQ desc in the ring every 32 descs, causing a
flush of the cache.  A0 parts are not production, but there are enough of
these parts in the wild in test setups to warrant including workaround.  A1
revision ASIC parts fix erratum.

Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-03 20:19:10 -07:00

217 lines
5.3 KiB
C

/*
* Copyright 2008 Cisco Systems, Inc. All rights reserved.
* Copyright 2007 Nuova 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.
*
*/
#ifndef _VNIC_RQ_H_
#define _VNIC_RQ_H_
#include <linux/pci.h>
#include "vnic_dev.h"
#include "vnic_cq.h"
/* Receive queue control */
struct vnic_rq_ctrl {
u64 ring_base; /* 0x00 */
u32 ring_size; /* 0x08 */
u32 pad0;
u32 posted_index; /* 0x10 */
u32 pad1;
u32 cq_index; /* 0x18 */
u32 pad2;
u32 enable; /* 0x20 */
u32 pad3;
u32 running; /* 0x28 */
u32 pad4;
u32 fetch_index; /* 0x30 */
u32 pad5;
u32 error_interrupt_enable; /* 0x38 */
u32 pad6;
u32 error_interrupt_offset; /* 0x40 */
u32 pad7;
u32 error_status; /* 0x48 */
u32 pad8;
u32 dropped_packet_count; /* 0x50 */
u32 pad9;
u32 dropped_packet_count_rc; /* 0x58 */
u32 pad10;
};
/* Break the vnic_rq_buf allocations into blocks of 64 entries */
#define VNIC_RQ_BUF_BLK_ENTRIES 64
#define VNIC_RQ_BUF_BLK_SZ \
(VNIC_RQ_BUF_BLK_ENTRIES * sizeof(struct vnic_rq_buf))
#define VNIC_RQ_BUF_BLKS_NEEDED(entries) \
DIV_ROUND_UP(entries, VNIC_RQ_BUF_BLK_ENTRIES)
#define VNIC_RQ_BUF_BLKS_MAX VNIC_RQ_BUF_BLKS_NEEDED(4096)
struct vnic_rq_buf {
struct vnic_rq_buf *next;
dma_addr_t dma_addr;
void *os_buf;
unsigned int os_buf_index;
unsigned int len;
unsigned int index;
void *desc;
};
struct vnic_rq {
unsigned int index;
struct vnic_dev *vdev;
struct vnic_rq_ctrl __iomem *ctrl; /* memory-mapped */
struct vnic_dev_ring ring;
struct vnic_rq_buf *bufs[VNIC_RQ_BUF_BLKS_MAX];
struct vnic_rq_buf *to_use;
struct vnic_rq_buf *to_clean;
void *os_buf_head;
unsigned int buf_index;
unsigned int pkts_outstanding;
};
static inline unsigned int vnic_rq_desc_avail(struct vnic_rq *rq)
{
/* how many does SW own? */
return rq->ring.desc_avail;
}
static inline unsigned int vnic_rq_desc_used(struct vnic_rq *rq)
{
/* how many does HW own? */
return rq->ring.desc_count - rq->ring.desc_avail - 1;
}
static inline void *vnic_rq_next_desc(struct vnic_rq *rq)
{
return rq->to_use->desc;
}
static inline unsigned int vnic_rq_next_index(struct vnic_rq *rq)
{
return rq->to_use->index;
}
static inline unsigned int vnic_rq_next_buf_index(struct vnic_rq *rq)
{
return rq->buf_index++;
}
static inline void vnic_rq_post(struct vnic_rq *rq,
void *os_buf, unsigned int os_buf_index,
dma_addr_t dma_addr, unsigned int len)
{
struct vnic_rq_buf *buf = rq->to_use;
buf->os_buf = os_buf;
buf->os_buf_index = os_buf_index;
buf->dma_addr = dma_addr;
buf->len = len;
buf = buf->next;
rq->to_use = buf;
rq->ring.desc_avail--;
/* Move the posted_index every nth descriptor
*/
#ifndef VNIC_RQ_RETURN_RATE
#define VNIC_RQ_RETURN_RATE 0xf /* keep 2^n - 1 */
#endif
if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) {
/* Adding write memory barrier prevents compiler and/or CPU
* reordering, thus avoiding descriptor posting before
* descriptor is initialized. Otherwise, hardware can read
* stale descriptor fields.
*/
wmb();
iowrite32(buf->index, &rq->ctrl->posted_index);
}
}
static inline int vnic_rq_posting_soon(struct vnic_rq *rq)
{
return ((rq->to_use->index & VNIC_RQ_RETURN_RATE) == 0);
}
static inline void vnic_rq_return_descs(struct vnic_rq *rq, unsigned int count)
{
rq->ring.desc_avail += count;
}
enum desc_return_options {
VNIC_RQ_RETURN_DESC,
VNIC_RQ_DEFER_RETURN_DESC,
};
static inline void vnic_rq_service(struct vnic_rq *rq,
struct cq_desc *cq_desc, u16 completed_index,
int desc_return, void (*buf_service)(struct vnic_rq *rq,
struct cq_desc *cq_desc, struct vnic_rq_buf *buf,
int skipped, void *opaque), void *opaque)
{
struct vnic_rq_buf *buf;
int skipped;
buf = rq->to_clean;
while (1) {
skipped = (buf->index != completed_index);
(*buf_service)(rq, cq_desc, buf, skipped, opaque);
if (desc_return == VNIC_RQ_RETURN_DESC)
rq->ring.desc_avail++;
rq->to_clean = buf->next;
if (!skipped)
break;
buf = rq->to_clean;
}
}
static inline int vnic_rq_fill(struct vnic_rq *rq,
int (*buf_fill)(struct vnic_rq *rq))
{
int err;
while (vnic_rq_desc_avail(rq) > 0) {
err = (*buf_fill)(rq);
if (err)
return err;
}
return 0;
}
void vnic_rq_free(struct vnic_rq *rq);
int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
unsigned int desc_count, unsigned int desc_size);
void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
unsigned int error_interrupt_enable,
unsigned int error_interrupt_offset);
unsigned int vnic_rq_error_status(struct vnic_rq *rq);
void vnic_rq_enable(struct vnic_rq *rq);
int vnic_rq_disable(struct vnic_rq *rq);
void vnic_rq_clean(struct vnic_rq *rq,
void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf));
#endif /* _VNIC_RQ_H_ */