1/*
2 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <rdma/ib_umem_odp.h>
34#include "mlx5_ib.h"
35#include <linux/jiffies.h>
36
37/*
38 * Fill in a physical address list. ib_umem_num_dma_blocks() entries will be
39 * filled in the pas array.
40 */
41void mlx5_ib_populate_pas(struct ib_umem *umem, size_t page_size, __be64 *pas,
42			  u64 access_flags)
43{
44	struct ib_block_iter biter;
45
46	rdma_umem_for_each_dma_block (umem, &biter, page_size) {
47		*pas = cpu_to_be64(rdma_block_iter_dma_address(&biter) |
48				   access_flags);
49		pas++;
50	}
51}
52
53/*
54 * Compute the page shift and page_offset for mailboxes that use a quantized
55 * page_offset. The granulatity of the page offset scales according to page
56 * size.
57 */
58unsigned long __mlx5_umem_find_best_quantized_pgoff(
59	struct ib_umem *umem, unsigned long pgsz_bitmap,
60	unsigned int page_offset_bits, u64 pgoff_bitmask, unsigned int scale,
61	unsigned int *page_offset_quantized)
62{
63	const u64 page_offset_mask = (1UL << page_offset_bits) - 1;
64	unsigned long page_size;
65	u64 page_offset;
66
67	page_size = ib_umem_find_best_pgoff(umem, pgsz_bitmap, pgoff_bitmask);
68	if (!page_size)
69		return 0;
70
71	/*
72	 * page size is the largest possible page size.
73	 *
74	 * Reduce the page_size, and thus the page_offset and quanta, until the
75	 * page_offset fits into the mailbox field. Once page_size < scale this
76	 * loop is guaranteed to terminate.
77	 */
78	page_offset = ib_umem_dma_offset(umem, page_size);
79	while (page_offset & ~(u64)(page_offset_mask * (page_size / scale))) {
80		page_size /= 2;
81		page_offset = ib_umem_dma_offset(umem, page_size);
82	}
83
84	/*
85	 * The address is not aligned, or otherwise cannot be represented by the
86	 * page_offset.
87	 */
88	if (!(pgsz_bitmap & page_size))
89		return 0;
90
91	*page_offset_quantized =
92		(unsigned long)page_offset / (page_size / scale);
93	if (WARN_ON(*page_offset_quantized > page_offset_mask))
94		return 0;
95	return page_size;
96}
97
98#define WR_ID_BF 0xBF
99#define WR_ID_END 0xBAD
100#define TEST_WC_NUM_WQES 255
101#define TEST_WC_POLLING_MAX_TIME_JIFFIES msecs_to_jiffies(100)
102static int post_send_nop(struct mlx5_ib_dev *dev, struct ib_qp *ibqp, u64 wr_id,
103			 bool signaled)
104{
105	struct mlx5_ib_qp *qp = to_mqp(ibqp);
106	struct mlx5_wqe_ctrl_seg *ctrl;
107	struct mlx5_bf *bf = &qp->bf;
108	__be32 mmio_wqe[16] = {};
109	unsigned long flags;
110	unsigned int idx;
111	int i;
112
113	if (unlikely(dev->mdev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR))
114		return -EIO;
115
116	spin_lock_irqsave(&qp->sq.lock, flags);
117
118	idx = qp->sq.cur_post & (qp->sq.wqe_cnt - 1);
119	ctrl = mlx5_frag_buf_get_wqe(&qp->sq.fbc, idx);
120
121	memset(ctrl, 0, sizeof(struct mlx5_wqe_ctrl_seg));
122	ctrl->fm_ce_se = signaled ? MLX5_WQE_CTRL_CQ_UPDATE : 0;
123	ctrl->opmod_idx_opcode =
124		cpu_to_be32(((u32)(qp->sq.cur_post) << 8) | MLX5_OPCODE_NOP);
125	ctrl->qpn_ds = cpu_to_be32((sizeof(struct mlx5_wqe_ctrl_seg) / 16) |
126				   (qp->trans_qp.base.mqp.qpn << 8));
127
128	qp->sq.wrid[idx] = wr_id;
129	qp->sq.w_list[idx].opcode = MLX5_OPCODE_NOP;
130	qp->sq.wqe_head[idx] = qp->sq.head + 1;
131	qp->sq.cur_post += DIV_ROUND_UP(sizeof(struct mlx5_wqe_ctrl_seg),
132					MLX5_SEND_WQE_BB);
133	qp->sq.w_list[idx].next = qp->sq.cur_post;
134	qp->sq.head++;
135
136	memcpy(mmio_wqe, ctrl, sizeof(*ctrl));
137	((struct mlx5_wqe_ctrl_seg *)&mmio_wqe)->fm_ce_se |=
138		MLX5_WQE_CTRL_CQ_UPDATE;
139
140	/* Make sure that descriptors are written before
141	 * updating doorbell record and ringing the doorbell
142	 */
143	wmb();
144
145	qp->db.db[MLX5_SND_DBR] = cpu_to_be32(qp->sq.cur_post);
146
147	/* Make sure doorbell record is visible to the HCA before
148	 * we hit doorbell
149	 */
150	wmb();
151	for (i = 0; i < 8; i++)
152		mlx5_write64(&mmio_wqe[i * 2],
153			     bf->bfreg->map + bf->offset + i * 8);
154	io_stop_wc();
155
156	bf->offset ^= bf->buf_size;
157
158	spin_unlock_irqrestore(&qp->sq.lock, flags);
159
160	return 0;
161}
162
163static int test_wc_poll_cq_result(struct mlx5_ib_dev *dev, struct ib_cq *cq)
164{
165	int ret;
166	struct ib_wc wc = {};
167	unsigned long end = jiffies + TEST_WC_POLLING_MAX_TIME_JIFFIES;
168
169	do {
170		ret = ib_poll_cq(cq, 1, &wc);
171		if (ret < 0 || wc.status)
172			return ret < 0 ? ret : -EINVAL;
173		if (ret)
174			break;
175	} while (!time_after(jiffies, end));
176
177	if (!ret)
178		return -ETIMEDOUT;
179
180	if (wc.wr_id != WR_ID_BF)
181		ret = 0;
182
183	return ret;
184}
185
186static int test_wc_do_send(struct mlx5_ib_dev *dev, struct ib_qp *qp)
187{
188	int err, i;
189
190	for (i = 0; i < TEST_WC_NUM_WQES; i++) {
191		err = post_send_nop(dev, qp, WR_ID_BF, false);
192		if (err)
193			return err;
194	}
195
196	return post_send_nop(dev, qp, WR_ID_END, true);
197}
198
199int mlx5_ib_test_wc(struct mlx5_ib_dev *dev)
200{
201	struct ib_cq_init_attr cq_attr = { .cqe = TEST_WC_NUM_WQES + 1 };
202	int port_type_cap = MLX5_CAP_GEN(dev->mdev, port_type);
203	struct ib_qp_init_attr qp_init_attr = {
204		.cap = { .max_send_wr = TEST_WC_NUM_WQES },
205		.qp_type = IB_QPT_UD,
206		.sq_sig_type = IB_SIGNAL_REQ_WR,
207		.create_flags = MLX5_IB_QP_CREATE_WC_TEST,
208	};
209	struct ib_qp_attr qp_attr = { .port_num = 1 };
210	struct ib_device *ibdev = &dev->ib_dev;
211	struct ib_qp *qp;
212	struct ib_cq *cq;
213	struct ib_pd *pd;
214	int ret;
215
216	if (!MLX5_CAP_GEN(dev->mdev, bf))
217		return 0;
218
219	if (!dev->mdev->roce.roce_en &&
220	    port_type_cap == MLX5_CAP_PORT_TYPE_ETH) {
221		if (mlx5_core_is_pf(dev->mdev))
222			dev->wc_support = arch_can_pci_mmap_wc();
223		return 0;
224	}
225
226	ret = mlx5_alloc_bfreg(dev->mdev, &dev->wc_bfreg, true, false);
227	if (ret)
228		goto print_err;
229
230	if (!dev->wc_bfreg.wc)
231		goto out1;
232
233	pd = ib_alloc_pd(ibdev, 0);
234	if (IS_ERR(pd)) {
235		ret = PTR_ERR(pd);
236		goto out1;
237	}
238
239	cq = ib_create_cq(ibdev, NULL, NULL, NULL, &cq_attr);
240	if (IS_ERR(cq)) {
241		ret = PTR_ERR(cq);
242		goto out2;
243	}
244
245	qp_init_attr.recv_cq = cq;
246	qp_init_attr.send_cq = cq;
247	qp = ib_create_qp(pd, &qp_init_attr);
248	if (IS_ERR(qp)) {
249		ret = PTR_ERR(qp);
250		goto out3;
251	}
252
253	qp_attr.qp_state = IB_QPS_INIT;
254	ret = ib_modify_qp(qp, &qp_attr,
255			   IB_QP_STATE | IB_QP_PORT | IB_QP_PKEY_INDEX |
256				   IB_QP_QKEY);
257	if (ret)
258		goto out4;
259
260	qp_attr.qp_state = IB_QPS_RTR;
261	ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
262	if (ret)
263		goto out4;
264
265	qp_attr.qp_state = IB_QPS_RTS;
266	ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_SQ_PSN);
267	if (ret)
268		goto out4;
269
270	ret = test_wc_do_send(dev, qp);
271	if (ret < 0)
272		goto out4;
273
274	ret = test_wc_poll_cq_result(dev, cq);
275	if (ret > 0) {
276		dev->wc_support = true;
277		ret = 0;
278	}
279
280out4:
281	ib_destroy_qp(qp);
282out3:
283	ib_destroy_cq(cq);
284out2:
285	ib_dealloc_pd(pd);
286out1:
287	mlx5_free_bfreg(dev->mdev, &dev->wc_bfreg);
288print_err:
289	if (ret)
290		mlx5_ib_err(
291			dev,
292			"Error %d while trying to test write-combining support\n",
293			ret);
294	return ret;
295}
296