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_RQ_H_ 19 #define _VNIC_RQ_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_rq_desc_avail fnic_rq_desc_avail 30 #define vnic_rq_desc_used fnic_rq_desc_used 31 #define vnic_rq_next_desc fnic_rq_next_desc 32 #define vnic_rq_next_index fnic_rq_next_index 33 #define vnic_rq_next_buf_index fnic_rq_next_buf_index 34 #define vnic_rq_post fnic_rq_post 35 #define vnic_rq_posting_soon fnic_rq_posting_soon 36 #define vnic_rq_return_descs fnic_rq_return_descs 37 #define vnic_rq_service fnic_rq_service 38 #define vnic_rq_fill fnic_rq_fill 39 #define vnic_rq_free fnic_rq_free 40 #define vnic_rq_alloc fnic_rq_alloc 41 #define vnic_rq_init fnic_rq_init 42 #define vnic_rq_error_status fnic_rq_error_status 43 #define vnic_rq_enable fnic_rq_enable 44 #define vnic_rq_disable fnic_rq_disable 45 #define vnic_rq_clean fnic_rq_clean 46 47 /* Receive queue control */ 48 struct vnic_rq_ctrl { 49 u64 ring_base; /* 0x00 */ 50 u32 ring_size; /* 0x08 */ 51 u32 pad0; 52 u32 posted_index; /* 0x10 */ 53 u32 pad1; 54 u32 cq_index; /* 0x18 */ 55 u32 pad2; 56 u32 enable; /* 0x20 */ 57 u32 pad3; 58 u32 running; /* 0x28 */ 59 u32 pad4; 60 u32 fetch_index; /* 0x30 */ 61 u32 pad5; 62 u32 error_interrupt_enable; /* 0x38 */ 63 u32 pad6; 64 u32 error_interrupt_offset; /* 0x40 */ 65 u32 pad7; 66 u32 error_status; /* 0x48 */ 67 u32 pad8; 68 u32 dropped_packet_count; /* 0x50 */ 69 u32 pad9; 70 u32 dropped_packet_count_rc; /* 0x58 */ 71 u32 pad10; 72 }; 73 74 /* Break the vnic_rq_buf allocations into blocks of 64 entries */ 75 #define VNIC_RQ_BUF_BLK_ENTRIES 64 76 #define VNIC_RQ_BUF_BLK_SZ \ 77 (VNIC_RQ_BUF_BLK_ENTRIES * sizeof(struct vnic_rq_buf)) 78 #define VNIC_RQ_BUF_BLKS_NEEDED(entries) \ 79 DIV_ROUND_UP(entries, VNIC_RQ_BUF_BLK_ENTRIES) 80 #define VNIC_RQ_BUF_BLKS_MAX VNIC_RQ_BUF_BLKS_NEEDED(4096) 81 82 struct vnic_rq_buf { 83 struct vnic_rq_buf *next; 84 dma_addr_t dma_addr; 85 void *os_buf; 86 unsigned int os_buf_index; 87 unsigned int len; 88 unsigned int index; 89 void *desc; 90 }; 91 92 struct vnic_rq { 93 unsigned int index; 94 struct vnic_dev *vdev; 95 struct vnic_rq_ctrl __iomem *ctrl; /* memory-mapped */ 96 struct vnic_dev_ring ring; 97 struct vnic_rq_buf *bufs[VNIC_RQ_BUF_BLKS_MAX]; 98 struct vnic_rq_buf *to_use; 99 struct vnic_rq_buf *to_clean; 100 void *os_buf_head; 101 unsigned int buf_index; 102 unsigned int pkts_outstanding; 103 }; 104 105 static inline unsigned int vnic_rq_desc_avail(struct vnic_rq *rq) 106 { 107 /* how many does SW own? */ 108 return rq->ring.desc_avail; 109 } 110 111 static inline unsigned int vnic_rq_desc_used(struct vnic_rq *rq) 112 { 113 /* how many does HW own? */ 114 return rq->ring.desc_count - rq->ring.desc_avail - 1; 115 } 116 117 static inline void *vnic_rq_next_desc(struct vnic_rq *rq) 118 { 119 return rq->to_use->desc; 120 } 121 122 static inline unsigned int vnic_rq_next_index(struct vnic_rq *rq) 123 { 124 return rq->to_use->index; 125 } 126 127 static inline unsigned int vnic_rq_next_buf_index(struct vnic_rq *rq) 128 { 129 return rq->buf_index++; 130 } 131 132 static inline void vnic_rq_post(struct vnic_rq *rq, 133 void *os_buf, unsigned int os_buf_index, 134 dma_addr_t dma_addr, unsigned int len) 135 { 136 struct vnic_rq_buf *buf = rq->to_use; 137 138 buf->os_buf = os_buf; 139 buf->os_buf_index = os_buf_index; 140 buf->dma_addr = dma_addr; 141 buf->len = len; 142 143 buf = buf->next; 144 rq->to_use = buf; 145 rq->ring.desc_avail--; 146 147 /* Move the posted_index every nth descriptor 148 */ 149 150 #ifndef VNIC_RQ_RETURN_RATE 151 #define VNIC_RQ_RETURN_RATE 0xf /* keep 2^n - 1 */ 152 #endif 153 154 if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) { 155 /* Adding write memory barrier prevents compiler and/or CPU 156 * reordering, thus avoiding descriptor posting before 157 * descriptor is initialized. Otherwise, hardware can read 158 * stale descriptor fields. 159 */ 160 wmb(); 161 iowrite32(buf->index, &rq->ctrl->posted_index); 162 } 163 } 164 165 static inline int vnic_rq_posting_soon(struct vnic_rq *rq) 166 { 167 return (rq->to_use->index & VNIC_RQ_RETURN_RATE) == 0; 168 } 169 170 static inline void vnic_rq_return_descs(struct vnic_rq *rq, unsigned int count) 171 { 172 rq->ring.desc_avail += count; 173 } 174 175 enum desc_return_options { 176 VNIC_RQ_RETURN_DESC, 177 VNIC_RQ_DEFER_RETURN_DESC, 178 }; 179 180 static inline void vnic_rq_service(struct vnic_rq *rq, 181 struct cq_desc *cq_desc, u16 completed_index, 182 int desc_return, void (*buf_service)(struct vnic_rq *rq, 183 struct cq_desc *cq_desc, struct vnic_rq_buf *buf, 184 int skipped, void *opaque), void *opaque) 185 { 186 struct vnic_rq_buf *buf; 187 int skipped; 188 189 buf = rq->to_clean; 190 while (1) { 191 192 skipped = (buf->index != completed_index); 193 194 (*buf_service)(rq, cq_desc, buf, skipped, opaque); 195 196 if (desc_return == VNIC_RQ_RETURN_DESC) 197 rq->ring.desc_avail++; 198 199 rq->to_clean = buf->next; 200 201 if (!skipped) 202 break; 203 204 buf = rq->to_clean; 205 } 206 } 207 208 static inline int vnic_rq_fill(struct vnic_rq *rq, 209 int (*buf_fill)(struct vnic_rq *rq)) 210 { 211 int err; 212 213 while (vnic_rq_desc_avail(rq) > 1) { 214 215 err = (*buf_fill)(rq); 216 if (err) 217 return err; 218 } 219 220 return 0; 221 } 222 223 void vnic_rq_free(struct vnic_rq *rq); 224 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index, 225 unsigned int desc_count, unsigned int desc_size); 226 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index, 227 unsigned int error_interrupt_enable, 228 unsigned int error_interrupt_offset); 229 unsigned int vnic_rq_error_status(struct vnic_rq *rq); 230 void vnic_rq_enable(struct vnic_rq *rq); 231 int vnic_rq_disable(struct vnic_rq *rq); 232 void vnic_rq_clean(struct vnic_rq *rq, 233 void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf)); 234 235 #endif /* _VNIC_RQ_H_ */ 236