1 /* 2 * Copyright 2008-2010 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 */ 19 20 #include <linux/kernel.h> 21 #include <linux/errno.h> 22 #include <linux/types.h> 23 #include <linux/pci.h> 24 #include <linux/delay.h> 25 #include <linux/slab.h> 26 27 #include "vnic_dev.h" 28 #include "vnic_rq.h" 29 #include "enic.h" 30 31 static int vnic_rq_alloc_bufs(struct vnic_rq *rq) 32 { 33 struct vnic_rq_buf *buf; 34 unsigned int i, j, count = rq->ring.desc_count; 35 unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count); 36 37 for (i = 0; i < blks; i++) { 38 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ(count), GFP_ATOMIC); 39 if (!rq->bufs[i]) 40 return -ENOMEM; 41 } 42 43 for (i = 0; i < blks; i++) { 44 buf = rq->bufs[i]; 45 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES(count); j++) { 46 buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES(count) + j; 47 buf->desc = (u8 *)rq->ring.descs + 48 rq->ring.desc_size * buf->index; 49 if (buf->index + 1 == count) { 50 buf->next = rq->bufs[0]; 51 break; 52 } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES(count)) { 53 buf->next = rq->bufs[i + 1]; 54 } else { 55 buf->next = buf + 1; 56 buf++; 57 } 58 } 59 } 60 61 rq->to_use = rq->to_clean = rq->bufs[0]; 62 63 return 0; 64 } 65 66 void vnic_rq_free(struct vnic_rq *rq) 67 { 68 struct vnic_dev *vdev; 69 unsigned int i; 70 71 vdev = rq->vdev; 72 73 vnic_dev_free_desc_ring(vdev, &rq->ring); 74 75 for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) { 76 if (rq->bufs[i]) { 77 kfree(rq->bufs[i]); 78 rq->bufs[i] = NULL; 79 } 80 } 81 82 rq->ctrl = NULL; 83 } 84 85 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index, 86 unsigned int desc_count, unsigned int desc_size) 87 { 88 int err; 89 90 rq->index = index; 91 rq->vdev = vdev; 92 93 rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index); 94 if (!rq->ctrl) { 95 vdev_err(vdev, "Failed to hook RQ[%d] resource\n", index); 96 return -EINVAL; 97 } 98 99 vnic_rq_disable(rq); 100 101 err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size); 102 if (err) 103 return err; 104 105 err = vnic_rq_alloc_bufs(rq); 106 if (err) { 107 vnic_rq_free(rq); 108 return err; 109 } 110 111 return 0; 112 } 113 114 static void vnic_rq_init_start(struct vnic_rq *rq, unsigned int cq_index, 115 unsigned int fetch_index, unsigned int posted_index, 116 unsigned int error_interrupt_enable, 117 unsigned int error_interrupt_offset) 118 { 119 u64 paddr; 120 unsigned int count = rq->ring.desc_count; 121 122 paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET; 123 writeq(paddr, &rq->ctrl->ring_base); 124 iowrite32(count, &rq->ctrl->ring_size); 125 iowrite32(cq_index, &rq->ctrl->cq_index); 126 iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable); 127 iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset); 128 iowrite32(0, &rq->ctrl->dropped_packet_count); 129 iowrite32(0, &rq->ctrl->error_status); 130 iowrite32(fetch_index, &rq->ctrl->fetch_index); 131 iowrite32(posted_index, &rq->ctrl->posted_index); 132 133 rq->to_use = rq->to_clean = 134 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)] 135 [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)]; 136 } 137 138 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index, 139 unsigned int error_interrupt_enable, 140 unsigned int error_interrupt_offset) 141 { 142 vnic_rq_init_start(rq, cq_index, 0, 0, error_interrupt_enable, 143 error_interrupt_offset); 144 } 145 146 unsigned int vnic_rq_error_status(struct vnic_rq *rq) 147 { 148 return ioread32(&rq->ctrl->error_status); 149 } 150 151 void vnic_rq_enable(struct vnic_rq *rq) 152 { 153 iowrite32(1, &rq->ctrl->enable); 154 } 155 156 int vnic_rq_disable(struct vnic_rq *rq) 157 { 158 unsigned int wait; 159 struct vnic_dev *vdev = rq->vdev; 160 int i; 161 162 /* Due to a race condition with clearing RQ "mini-cache" in hw, we need 163 * to disable the RQ twice to guarantee that stale descriptors are not 164 * used when this RQ is re-enabled. 165 */ 166 for (i = 0; i < 2; i++) { 167 iowrite32(0, &rq->ctrl->enable); 168 169 /* Wait for HW to ACK disable request */ 170 for (wait = 20000; wait > 0; wait--) 171 if (!ioread32(&rq->ctrl->running)) 172 break; 173 if (!wait) { 174 vdev_neterr(vdev, "Failed to disable RQ[%d]\n", 175 rq->index); 176 177 return -ETIMEDOUT; 178 } 179 } 180 181 return 0; 182 } 183 184 void vnic_rq_clean(struct vnic_rq *rq, 185 void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf)) 186 { 187 struct vnic_rq_buf *buf; 188 u32 fetch_index; 189 unsigned int count = rq->ring.desc_count; 190 int i; 191 192 buf = rq->to_clean; 193 194 for (i = 0; i < rq->ring.desc_count; i++) { 195 (*buf_clean)(rq, buf); 196 buf = buf->next; 197 } 198 rq->ring.desc_avail = rq->ring.desc_count - 1; 199 200 /* Use current fetch_index as the ring starting point */ 201 fetch_index = ioread32(&rq->ctrl->fetch_index); 202 203 if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone */ 204 /* Hardware surprise removal: reset fetch_index */ 205 fetch_index = 0; 206 } 207 rq->to_use = rq->to_clean = 208 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)] 209 [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)]; 210 iowrite32(fetch_index, &rq->ctrl->posted_index); 211 212 /* Anytime we write fetch_index, we need to re-write 0 to rq->enable 213 * to re-sync internal VIC state. 214 */ 215 iowrite32(0, &rq->ctrl->enable); 216 217 vnic_dev_clear_desc_ring(&rq->ring); 218 } 219 220