drivers/scsi/snic/vnic_cq.h

   1 /*
   2  * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
   3  *
   4  * This program is free software; you may redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  15  * SOFTWARE.
  16  */
  17
  18 #ifndef _VNIC_CQ_H_
  19 #define _VNIC_CQ_H_
  20
  21 #include "cq_desc.h"
  22 #include "vnic_dev.h"
  23
  24 /* Completion queue control */
  25 struct vnic_cq_ctrl {
  26         u64 ring_base;                  /* 0x00 */
  27         u32 ring_size;                  /* 0x08 */
  28         u32 pad0;
  29         u32 flow_control_enable;        /* 0x10 */
  30         u32 pad1;
  31         u32 color_enable;               /* 0x18 */
  32         u32 pad2;
  33         u32 cq_head;                    /* 0x20 */
  34         u32 pad3;
  35         u32 cq_tail;                    /* 0x28 */
  36         u32 pad4;
  37         u32 cq_tail_color;              /* 0x30 */
  38         u32 pad5;
  39         u32 interrupt_enable;           /* 0x38 */
  40         u32 pad6;
  41         u32 cq_entry_enable;            /* 0x40 */
  42         u32 pad7;
  43         u32 cq_message_enable;          /* 0x48 */
  44         u32 pad8;
  45         u32 interrupt_offset;           /* 0x50 */
  46         u32 pad9;
  47         u64 cq_message_addr;            /* 0x58 */
  48         u32 pad10;
  49 };
  50
  51 struct vnic_cq {
  52         unsigned int index;
  53         struct vnic_dev *vdev;
  54         struct vnic_cq_ctrl __iomem *ctrl;      /* memory-mapped */
  55         struct vnic_dev_ring ring;
  56         unsigned int to_clean;
  57         unsigned int last_color;
  58 };
  59
  60 static inline unsigned int svnic_cq_service(struct vnic_cq *cq,
  61         unsigned int work_to_do,
  62         int (*q_service)(struct vnic_dev *vdev, struct cq_desc *cq_desc,
  63         u8 type, u16 q_number, u16 completed_index, void *opaque),
  64         void *opaque)
  65 {
  66         struct cq_desc *cq_desc;
  67         unsigned int work_done = 0;
  68         u16 q_number, completed_index;
  69         u8 type, color;
  70
  71         cq_desc = (struct cq_desc *)((u8 *)cq->ring.descs +
  72                 cq->ring.desc_size * cq->to_clean);
  73         cq_desc_dec(cq_desc, &type, &color,
  74                 &q_number, &completed_index);
  75
  76         while (color != cq->last_color) {
  77
  78                 if ((*q_service)(cq->vdev, cq_desc, type,
  79                         q_number, completed_index, opaque))
  80                         break;
  81
  82                 cq->to_clean++;
  83                 if (cq->to_clean == cq->ring.desc_count) {
  84                         cq->to_clean = 0;
  85                         cq->last_color = cq->last_color ? 0 : 1;
  86                 }
  87
  88                 cq_desc = (struct cq_desc *)((u8 *)cq->ring.descs +
  89                         cq->ring.desc_size * cq->to_clean);
  90                 cq_desc_dec(cq_desc, &type, &color,
  91                         &q_number, &completed_index);
  92
  93                 work_done++;
  94                 if (work_done >= work_to_do)
  95                         break;
  96         }
  97
  98         return work_done;
  99 }
 100
 101 void svnic_cq_free(struct vnic_cq *cq);
 102 int svnic_cq_alloc(struct vnic_dev *vdev, struct vnic_cq *cq,
 103         unsigned int index, unsigned int desc_count, unsigned int desc_size);
 104 void svnic_cq_init(struct vnic_cq *cq, unsigned int flow_control_enable,
 105         unsigned int color_enable, unsigned int cq_head, unsigned int cq_tail,
 106         unsigned int cq_tail_color, unsigned int interrupt_enable,
 107         unsigned int cq_entry_enable, unsigned int message_enable,
 108         unsigned int interrupt_offset, u64 message_addr);
 109 void svnic_cq_clean(struct vnic_cq *cq);
 110 #endif /* _VNIC_CQ_H_ */