drivers/scsi/fnic/vnic_wq.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
   4  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
   5  */
   6 #ifndef _VNIC_WQ_H_
   7 #define _VNIC_WQ_H_
   8
   9 #include <linux/pci.h>
  10 #include "vnic_dev.h"
  11 #include "vnic_cq.h"
  12
  13 /*
  14  * These defines avoid symbol clash between fnic and enic (Cisco 10G Eth
  15  * Driver) when both are built with CONFIG options =y
  16  */
  17 #define vnic_wq_desc_avail fnic_wq_desc_avail
  18 #define vnic_wq_desc_used fnic_wq_desc_used
  19 #define vnic_wq_next_desc fni_cwq_next_desc
  20 #define vnic_wq_post fnic_wq_post
  21 #define vnic_wq_service fnic_wq_service
  22 #define vnic_wq_free fnic_wq_free
  23 #define vnic_wq_alloc fnic_wq_alloc
  24 #define vnic_wq_devcmd2_alloc fnic_wq_devcmd2_alloc
  25 #define vnic_wq_init_start fnic_wq_init_start
  26 #define vnic_wq_init fnic_wq_init
  27 #define vnic_wq_error_status fnic_wq_error_status
  28 #define vnic_wq_enable fnic_wq_enable
  29 #define vnic_wq_disable fnic_wq_disable
  30 #define vnic_wq_clean fnic_wq_clean
  31
  32 /* Work queue control */
  33 struct vnic_wq_ctrl {
  34         u64 ring_base;                  /* 0x00 */
  35         u32 ring_size;                  /* 0x08 */
  36         u32 pad0;
  37         u32 posted_index;               /* 0x10 */
  38         u32 pad1;
  39         u32 cq_index;                   /* 0x18 */
  40         u32 pad2;
  41         u32 enable;                     /* 0x20 */
  42         u32 pad3;
  43         u32 running;                    /* 0x28 */
  44         u32 pad4;
  45         u32 fetch_index;                /* 0x30 */
  46         u32 pad5;
  47         u32 dca_value;                  /* 0x38 */
  48         u32 pad6;
  49         u32 error_interrupt_enable;     /* 0x40 */
  50         u32 pad7;
  51         u32 error_interrupt_offset;     /* 0x48 */
  52         u32 pad8;
  53         u32 error_status;               /* 0x50 */
  54         u32 pad9;
  55 };
  56
  57 struct vnic_wq_buf {
  58         struct vnic_wq_buf *next;
  59         dma_addr_t dma_addr;
  60         void *os_buf;
  61         unsigned int len;
  62         unsigned int index;
  63         int sop;
  64         void *desc;
  65 };
  66
  67 /* Break the vnic_wq_buf allocations into blocks of 64 entries */
  68 #define VNIC_WQ_BUF_BLK_ENTRIES 64
  69 #define VNIC_WQ_BUF_BLK_SZ \
  70         (VNIC_WQ_BUF_BLK_ENTRIES * sizeof(struct vnic_wq_buf))
  71 #define VNIC_WQ_BUF_BLKS_NEEDED(entries) \
  72         DIV_ROUND_UP(entries, VNIC_WQ_BUF_BLK_ENTRIES)
  73 #define VNIC_WQ_BUF_BLKS_MAX VNIC_WQ_BUF_BLKS_NEEDED(4096)
  74
  75 struct vnic_wq {
  76         unsigned int index;
  77         struct vnic_dev *vdev;
  78         struct vnic_wq_ctrl __iomem *ctrl;      /* memory-mapped */
  79         struct vnic_dev_ring ring;
  80         struct vnic_wq_buf *bufs[VNIC_WQ_BUF_BLKS_MAX];
  81         struct vnic_wq_buf *to_use;
  82         struct vnic_wq_buf *to_clean;
  83         unsigned int pkts_outstanding;
  84 };
  85
  86 static inline unsigned int vnic_wq_desc_avail(struct vnic_wq *wq)
  87 {
  88         /* how many does SW own? */
  89         return wq->ring.desc_avail;
  90 }
  91
  92 static inline unsigned int vnic_wq_desc_used(struct vnic_wq *wq)
  93 {
  94         /* how many does HW own? */
  95         return wq->ring.desc_count - wq->ring.desc_avail - 1;
  96 }
  97
  98 static inline void *vnic_wq_next_desc(struct vnic_wq *wq)
  99 {
 100         return wq->to_use->desc;
 101 }
 102
 103 static inline void vnic_wq_post(struct vnic_wq *wq,
 104         void *os_buf, dma_addr_t dma_addr,
 105         unsigned int len, int sop, int eop)
 106 {
 107         struct vnic_wq_buf *buf = wq->to_use;
 108
 109         buf->sop = sop;
 110         buf->os_buf = eop ? os_buf : NULL;
 111         buf->dma_addr = dma_addr;
 112         buf->len = len;
 113
 114         buf = buf->next;
 115         if (eop) {
 116                 /* Adding write memory barrier prevents compiler and/or CPU
 117                  * reordering, thus avoiding descriptor posting before
 118                  * descriptor is initialized. Otherwise, hardware can read
 119                  * stale descriptor fields.
 120                  */
 121                 wmb();
 122                 iowrite32(buf->index, &wq->ctrl->posted_index);
 123         }
 124         wq->to_use = buf;
 125
 126         wq->ring.desc_avail--;
 127 }
 128
 129 static inline void vnic_wq_service(struct vnic_wq *wq,
 130         struct cq_desc *cq_desc, u16 completed_index,
 131         void (*buf_service)(struct vnic_wq *wq,
 132         struct cq_desc *cq_desc, struct vnic_wq_buf *buf, void *opaque),
 133         void *opaque)
 134 {
 135         struct vnic_wq_buf *buf;
 136
 137         buf = wq->to_clean;
 138         while (1) {
 139
 140                 (*buf_service)(wq, cq_desc, buf, opaque);
 141
 142                 wq->ring.desc_avail++;
 143
 144                 wq->to_clean = buf->next;
 145
 146                 if (buf->index == completed_index)
 147                         break;
 148
 149                 buf = wq->to_clean;
 150         }
 151 }
 152
 153 void vnic_wq_free(struct vnic_wq *wq);
 154 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
 155         unsigned int desc_count, unsigned int desc_size);
 156 int vnic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
 157                 unsigned int desc_count, unsigned int desc_size);
 158 void vnic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
 159                 unsigned int fetch_index, unsigned int posted_index,
 160                 unsigned int error_interrupt_enable,
 161                 unsigned int error_interrupt_offset);
 162 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
 163         unsigned int error_interrupt_enable,
 164         unsigned int error_interrupt_offset);
 165 unsigned int vnic_wq_error_status(struct vnic_wq *wq);
 166 void vnic_wq_enable(struct vnic_wq *wq);
 167 int vnic_wq_disable(struct vnic_wq *wq);
 168 void vnic_wq_clean(struct vnic_wq *wq,
 169         void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf));
 170
 171 #endif /* _VNIC_WQ_H_ */