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_COPY_H_ 7 #define _VNIC_WQ_COPY_H_ 8 9 #include <linux/pci.h> 10 #include "vnic_wq.h" 11 #include "fcpio.h" 12 13 #define VNIC_WQ_COPY_MAX 1 14 15 struct vnic_wq_copy { 16 unsigned int index; 17 struct vnic_dev *vdev; 18 struct vnic_wq_ctrl __iomem *ctrl; /* memory-mapped */ 19 struct vnic_dev_ring ring; 20 unsigned to_use_index; 21 unsigned to_clean_index; 22 }; 23 24 static inline unsigned int vnic_wq_copy_desc_avail(struct vnic_wq_copy *wq) 25 { 26 return wq->ring.desc_avail; 27 } 28 29 static inline unsigned int vnic_wq_copy_desc_in_use(struct vnic_wq_copy *wq) 30 { 31 return wq->ring.desc_count - 1 - wq->ring.desc_avail; 32 } 33 34 static inline void *vnic_wq_copy_next_desc(struct vnic_wq_copy *wq) 35 { 36 struct fcpio_host_req *desc = wq->ring.descs; 37 return &desc[wq->to_use_index]; 38 } 39 40 static inline void vnic_wq_copy_post(struct vnic_wq_copy *wq) 41 { 42 43 ((wq->to_use_index + 1) == wq->ring.desc_count) ? 44 (wq->to_use_index = 0) : (wq->to_use_index++); 45 wq->ring.desc_avail--; 46 47 /* Adding write memory barrier prevents compiler and/or CPU 48 * reordering, thus avoiding descriptor posting before 49 * descriptor is initialized. Otherwise, hardware can read 50 * stale descriptor fields. 51 */ 52 wmb(); 53 54 iowrite32(wq->to_use_index, &wq->ctrl->posted_index); 55 } 56 57 static inline void vnic_wq_copy_desc_process(struct vnic_wq_copy *wq, u16 index) 58 { 59 unsigned int cnt; 60 61 if (wq->to_clean_index <= index) 62 cnt = (index - wq->to_clean_index) + 1; 63 else 64 cnt = wq->ring.desc_count - wq->to_clean_index + index + 1; 65 66 wq->to_clean_index = ((index + 1) % wq->ring.desc_count); 67 wq->ring.desc_avail += cnt; 68 69 } 70 71 static inline void vnic_wq_copy_service(struct vnic_wq_copy *wq, 72 u16 completed_index, 73 void (*q_service)(struct vnic_wq_copy *wq, 74 struct fcpio_host_req *wq_desc)) 75 { 76 struct fcpio_host_req *wq_desc = wq->ring.descs; 77 unsigned int curr_index; 78 79 while (1) { 80 81 if (q_service) 82 (*q_service)(wq, &wq_desc[wq->to_clean_index]); 83 84 wq->ring.desc_avail++; 85 86 curr_index = wq->to_clean_index; 87 88 /* increment the to-clean index so that we start 89 * with an unprocessed index next time we enter the loop 90 */ 91 ((wq->to_clean_index + 1) == wq->ring.desc_count) ? 92 (wq->to_clean_index = 0) : (wq->to_clean_index++); 93 94 if (curr_index == completed_index) 95 break; 96 97 /* we have cleaned all the entries */ 98 if ((completed_index == (u16)-1) && 99 (wq->to_clean_index == wq->to_use_index)) 100 break; 101 } 102 } 103 104 void vnic_wq_copy_enable(struct vnic_wq_copy *wq); 105 int vnic_wq_copy_disable(struct vnic_wq_copy *wq); 106 void vnic_wq_copy_free(struct vnic_wq_copy *wq); 107 int vnic_wq_copy_alloc(struct vnic_dev *vdev, struct vnic_wq_copy *wq, 108 unsigned int index, unsigned int desc_count, unsigned int desc_size); 109 void vnic_wq_copy_init(struct vnic_wq_copy *wq, unsigned int cq_index, 110 unsigned int error_interrupt_enable, 111 unsigned int error_interrupt_offset); 112 void vnic_wq_copy_clean(struct vnic_wq_copy *wq, 113 void (*q_clean)(struct vnic_wq_copy *wq, 114 struct fcpio_host_req *wq_desc)); 115 116 #endif /* _VNIC_WQ_COPY_H_ */ 117