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_COPY_H_ 19 #define _VNIC_WQ_COPY_H_ 20 21 #include <linux/pci.h> 22 #include "vnic_wq.h" 23 #include "fcpio.h" 24 25 #define VNIC_WQ_COPY_MAX 1 26 27 struct vnic_wq_copy { 28 unsigned int index; 29 struct vnic_dev *vdev; 30 struct vnic_wq_ctrl __iomem *ctrl; /* memory-mapped */ 31 struct vnic_dev_ring ring; 32 unsigned to_use_index; 33 unsigned to_clean_index; 34 }; 35 36 static inline unsigned int vnic_wq_copy_desc_avail(struct vnic_wq_copy *wq) 37 { 38 return wq->ring.desc_avail; 39 } 40 41 static inline unsigned int vnic_wq_copy_desc_in_use(struct vnic_wq_copy *wq) 42 { 43 return wq->ring.desc_count - 1 - wq->ring.desc_avail; 44 } 45 46 static inline void *vnic_wq_copy_next_desc(struct vnic_wq_copy *wq) 47 { 48 struct fcpio_host_req *desc = wq->ring.descs; 49 return &desc[wq->to_use_index]; 50 } 51 52 static inline void vnic_wq_copy_post(struct vnic_wq_copy *wq) 53 { 54 55 ((wq->to_use_index + 1) == wq->ring.desc_count) ? 56 (wq->to_use_index = 0) : (wq->to_use_index++); 57 wq->ring.desc_avail--; 58 59 /* Adding write memory barrier prevents compiler and/or CPU 60 * reordering, thus avoiding descriptor posting before 61 * descriptor is initialized. Otherwise, hardware can read 62 * stale descriptor fields. 63 */ 64 wmb(); 65 66 iowrite32(wq->to_use_index, &wq->ctrl->posted_index); 67 } 68 69 static inline void vnic_wq_copy_desc_process(struct vnic_wq_copy *wq, u16 index) 70 { 71 unsigned int cnt; 72 73 if (wq->to_clean_index <= index) 74 cnt = (index - wq->to_clean_index) + 1; 75 else 76 cnt = wq->ring.desc_count - wq->to_clean_index + index + 1; 77 78 wq->to_clean_index = ((index + 1) % wq->ring.desc_count); 79 wq->ring.desc_avail += cnt; 80 81 } 82 83 static inline void vnic_wq_copy_service(struct vnic_wq_copy *wq, 84 u16 completed_index, 85 void (*q_service)(struct vnic_wq_copy *wq, 86 struct fcpio_host_req *wq_desc)) 87 { 88 struct fcpio_host_req *wq_desc = wq->ring.descs; 89 unsigned int curr_index; 90 91 while (1) { 92 93 if (q_service) 94 (*q_service)(wq, &wq_desc[wq->to_clean_index]); 95 96 wq->ring.desc_avail++; 97 98 curr_index = wq->to_clean_index; 99 100 /* increment the to-clean index so that we start 101 * with an unprocessed index next time we enter the loop 102 */ 103 ((wq->to_clean_index + 1) == wq->ring.desc_count) ? 104 (wq->to_clean_index = 0) : (wq->to_clean_index++); 105 106 if (curr_index == completed_index) 107 break; 108 109 /* we have cleaned all the entries */ 110 if ((completed_index == (u16)-1) && 111 (wq->to_clean_index == wq->to_use_index)) 112 break; 113 } 114 } 115 116 void vnic_wq_copy_enable(struct vnic_wq_copy *wq); 117 int vnic_wq_copy_disable(struct vnic_wq_copy *wq); 118 void vnic_wq_copy_free(struct vnic_wq_copy *wq); 119 int vnic_wq_copy_alloc(struct vnic_dev *vdev, struct vnic_wq_copy *wq, 120 unsigned int index, unsigned int desc_count, unsigned int desc_size); 121 void vnic_wq_copy_init(struct vnic_wq_copy *wq, unsigned int cq_index, 122 unsigned int error_interrupt_enable, 123 unsigned int error_interrupt_offset); 124 void vnic_wq_copy_clean(struct vnic_wq_copy *wq, 125 void (*q_clean)(struct vnic_wq_copy *wq, 126 struct fcpio_host_req *wq_desc)); 127 128 #endif /* _VNIC_WQ_COPY_H_ */ 129