drivers/scsi/fnic/vnic_wq.h

   1 /*
   2  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
   3  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
   4  *
   5  * This program is free software; you may redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; version 2 of the License.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  10  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  11  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  12  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  13  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  14  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  15  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  16  * SOFTWARE.
  17  */
  18 #ifndef _VNIC_WQ_H_
  19 #define _VNIC_WQ_H_
  20
  21 #include <linux/pci.h>
  22 #include "vnic_dev.h"
  23 #include "vnic_cq.h"
  24
  25 /*
  26  * These defines avoid symbol clash between fnic and enic (Cisco 10G Eth
  27  * Driver) when both are built with CONFIG options =y
  28  */
  29 #define vnic_wq_desc_avail fnic_wq_desc_avail
  30 #define vnic_wq_desc_used fnic_wq_desc_used
  31 #define vnic_wq_next_desc fni_cwq_next_desc
  32 #define vnic_wq_post fnic_wq_post
  33 #define vnic_wq_service fnic_wq_service
  34 #define vnic_wq_free fnic_wq_free
  35 #define vnic_wq_alloc fnic_wq_alloc
  36 #define vnic_wq_init fnic_wq_init
  37 #define vnic_wq_error_status fnic_wq_error_status
  38 #define vnic_wq_enable fnic_wq_enable
  39 #define vnic_wq_disable fnic_wq_disable
  40 #define vnic_wq_clean fnic_wq_clean
  41
  42 /* Work queue control */
  43 struct vnic_wq_ctrl {
  44         u64 ring_base;                  /* 0x00 */
  45         u32 ring_size;                  /* 0x08 */
  46         u32 pad0;
  47         u32 posted_index;               /* 0x10 */
  48         u32 pad1;
  49         u32 cq_index;                   /* 0x18 */
  50         u32 pad2;
  51         u32 enable;                     /* 0x20 */
  52         u32 pad3;
  53         u32 running;                    /* 0x28 */
  54         u32 pad4;
  55         u32 fetch_index;                /* 0x30 */
  56         u32 pad5;
  57         u32 dca_value;                  /* 0x38 */
  58         u32 pad6;
  59         u32 error_interrupt_enable;     /* 0x40 */
  60         u32 pad7;
  61         u32 error_interrupt_offset;     /* 0x48 */
  62         u32 pad8;
  63         u32 error_status;               /* 0x50 */
  64         u32 pad9;
  65 };
  66
  67 struct vnic_wq_buf {
  68         struct vnic_wq_buf *next;
  69         dma_addr_t dma_addr;
  70         void *os_buf;
  71         unsigned int len;
  72         unsigned int index;
  73         int sop;
  74         void *desc;
  75 };
  76
  77 /* Break the vnic_wq_buf allocations into blocks of 64 entries */
  78 #define VNIC_WQ_BUF_BLK_ENTRIES 64
  79 #define VNIC_WQ_BUF_BLK_SZ \
  80         (VNIC_WQ_BUF_BLK_ENTRIES * sizeof(struct vnic_wq_buf))
  81 #define VNIC_WQ_BUF_BLKS_NEEDED(entries) \
  82         DIV_ROUND_UP(entries, VNIC_WQ_BUF_BLK_ENTRIES)
  83 #define VNIC_WQ_BUF_BLKS_MAX VNIC_WQ_BUF_BLKS_NEEDED(4096)
  84
  85 struct vnic_wq {
  86         unsigned int index;
  87         struct vnic_dev *vdev;
  88         struct vnic_wq_ctrl __iomem *ctrl;      /* memory-mapped */
  89         struct vnic_dev_ring ring;
  90         struct vnic_wq_buf *bufs[VNIC_WQ_BUF_BLKS_MAX];
  91         struct vnic_wq_buf *to_use;
  92         struct vnic_wq_buf *to_clean;
  93         unsigned int pkts_outstanding;
  94 };
  95
  96 static inline unsigned int vnic_wq_desc_avail(struct vnic_wq *wq)
  97 {
  98         /* how many does SW own? */
  99         return wq->ring.desc_avail;
 100 }
 101
 102 static inline unsigned int vnic_wq_desc_used(struct vnic_wq *wq)
 103 {
 104         /* how many does HW own? */
 105         return wq->ring.desc_count - wq->ring.desc_avail - 1;
 106 }
 107
 108 static inline void *vnic_wq_next_desc(struct vnic_wq *wq)
 109 {
 110         return wq->to_use->desc;
 111 }
 112
 113 static inline void vnic_wq_post(struct vnic_wq *wq,
 114         void *os_buf, dma_addr_t dma_addr,
 115         unsigned int len, int sop, int eop)
 116 {
 117         struct vnic_wq_buf *buf = wq->to_use;
 118
 119         buf->sop = sop;
 120         buf->os_buf = eop ? os_buf : NULL;
 121         buf->dma_addr = dma_addr;
 122         buf->len = len;
 123
 124         buf = buf->next;
 125         if (eop) {
 126                 /* Adding write memory barrier prevents compiler and/or CPU
 127                  * reordering, thus avoiding descriptor posting before
 128                  * descriptor is initialized. Otherwise, hardware can read
 129                  * stale descriptor fields.
 130                  */
 131                 wmb();
 132                 iowrite32(buf->index, &wq->ctrl->posted_index);
 133         }
 134         wq->to_use = buf;
 135
 136         wq->ring.desc_avail--;
 137 }
 138
 139 static inline void vnic_wq_service(struct vnic_wq *wq,
 140         struct cq_desc *cq_desc, u16 completed_index,
 141         void (*buf_service)(struct vnic_wq *wq,
 142         struct cq_desc *cq_desc, struct vnic_wq_buf *buf, void *opaque),
 143         void *opaque)
 144 {
 145         struct vnic_wq_buf *buf;
 146
 147         buf = wq->to_clean;
 148         while (1) {
 149
 150                 (*buf_service)(wq, cq_desc, buf, opaque);
 151
 152                 wq->ring.desc_avail++;
 153
 154                 wq->to_clean = buf->next;
 155
 156                 if (buf->index == completed_index)
 157                         break;
 158
 159                 buf = wq->to_clean;
 160         }
 161 }
 162
 163 void vnic_wq_free(struct vnic_wq *wq);
 164 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
 165         unsigned int desc_count, unsigned int desc_size);
 166 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
 167         unsigned int error_interrupt_enable,
 168         unsigned int error_interrupt_offset);
 169 unsigned int vnic_wq_error_status(struct vnic_wq *wq);
 170 void vnic_wq_enable(struct vnic_wq *wq);
 171 int vnic_wq_disable(struct vnic_wq *wq);
 172 void vnic_wq_clean(struct vnic_wq *wq,
 173         void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf));
 174
 175 #endif /* _VNIC_WQ_H_ */