xref: /openbmc/linux/drivers/infiniband/hw/hfi1/msix.c (revision 5b4cb650)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3  * Copyright(c) 2018 Intel Corporation.
4  *
5  * This file is provided under a dual BSD/GPLv2 license.  When using or
6  * redistributing this file, you may do so under either license.
7  *
8  * GPL LICENSE SUMMARY
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of version 2 of the GNU General Public License as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * BSD LICENSE
20  *
21  * Redistribution and use in source and binary forms, with or without
22  * modification, are permitted provided that the following conditions
23  * are met:
24  *
25  *  - Redistributions of source code must retain the above copyright
26  *    notice, this list of conditions and the following disclaimer.
27  *  - Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in
29  *    the documentation and/or other materials provided with the
30  *    distribution.
31  *  - Neither the name of Intel Corporation nor the names of its
32  *    contributors may be used to endorse or promote products derived
33  *    from this software without specific prior written permission.
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
38  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
39  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
45  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
46  *
47  */
48 
49 #include "hfi.h"
50 #include "affinity.h"
51 #include "sdma.h"
52 
53 /**
54  * msix_initialize() - Calculate, request and configure MSIx IRQs
55  * @dd: valid hfi1 devdata
56  *
57  */
58 int msix_initialize(struct hfi1_devdata *dd)
59 {
60 	u32 total;
61 	int ret;
62 	struct hfi1_msix_entry *entries;
63 
64 	/*
65 	 * MSIx interrupt count:
66 	 *	one for the general, "slow path" interrupt
67 	 *	one per used SDMA engine
68 	 *	one per kernel receive context
69 	 *	one for each VNIC context
70 	 *      ...any new IRQs should be added here.
71 	 */
72 	total = 1 + dd->num_sdma + dd->n_krcv_queues + dd->num_vnic_contexts;
73 
74 	if (total >= CCE_NUM_MSIX_VECTORS)
75 		return -EINVAL;
76 
77 	ret = pci_alloc_irq_vectors(dd->pcidev, total, total, PCI_IRQ_MSIX);
78 	if (ret < 0) {
79 		dd_dev_err(dd, "pci_alloc_irq_vectors() failed: %d\n", ret);
80 		return ret;
81 	}
82 
83 	entries = kcalloc(total, sizeof(*dd->msix_info.msix_entries),
84 			  GFP_KERNEL);
85 	if (!entries) {
86 		pci_free_irq_vectors(dd->pcidev);
87 		return -ENOMEM;
88 	}
89 
90 	dd->msix_info.msix_entries = entries;
91 	spin_lock_init(&dd->msix_info.msix_lock);
92 	bitmap_zero(dd->msix_info.in_use_msix, total);
93 	dd->msix_info.max_requested = total;
94 	dd_dev_info(dd, "%u MSI-X interrupts allocated\n", total);
95 
96 	return 0;
97 }
98 
99 /**
100  * msix_request_irq() - Allocate a free MSIx IRQ
101  * @dd: valid devdata
102  * @arg: context information for the IRQ
103  * @handler: IRQ handler
104  * @thread: IRQ thread handler (could be NULL)
105  * @idx: zero base idx if multiple devices are needed
106  * @type: affinty IRQ type
107  *
108  * Allocated an MSIx vector if available, and then create the appropriate
109  * meta data needed to keep track of the pci IRQ request.
110  *
111  * Return:
112  *   < 0   Error
113  *   >= 0  MSIx vector
114  *
115  */
116 static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
117 			    irq_handler_t handler, irq_handler_t thread,
118 			    u32 idx, enum irq_type type)
119 {
120 	unsigned long nr;
121 	int irq;
122 	int ret;
123 	const char *err_info;
124 	char name[MAX_NAME_SIZE];
125 	struct hfi1_msix_entry *me;
126 
127 	/* Allocate an MSIx vector */
128 	spin_lock(&dd->msix_info.msix_lock);
129 	nr = find_first_zero_bit(dd->msix_info.in_use_msix,
130 				 dd->msix_info.max_requested);
131 	if (nr < dd->msix_info.max_requested)
132 		__set_bit(nr, dd->msix_info.in_use_msix);
133 	spin_unlock(&dd->msix_info.msix_lock);
134 
135 	if (nr == dd->msix_info.max_requested)
136 		return -ENOSPC;
137 
138 	/* Specific verification and determine the name */
139 	switch (type) {
140 	case IRQ_GENERAL:
141 		/* general interrupt must be MSIx vector 0 */
142 		if (nr) {
143 			spin_lock(&dd->msix_info.msix_lock);
144 			__clear_bit(nr, dd->msix_info.in_use_msix);
145 			spin_unlock(&dd->msix_info.msix_lock);
146 			dd_dev_err(dd, "Invalid index %lu for GENERAL IRQ\n",
147 				   nr);
148 			return -EINVAL;
149 		}
150 		snprintf(name, sizeof(name), DRIVER_NAME "_%d", dd->unit);
151 		err_info = "general";
152 		break;
153 	case IRQ_SDMA:
154 		snprintf(name, sizeof(name), DRIVER_NAME "_%d sdma%d",
155 			 dd->unit, idx);
156 		err_info = "sdma";
157 		break;
158 	case IRQ_RCVCTXT:
159 		snprintf(name, sizeof(name), DRIVER_NAME "_%d kctxt%d",
160 			 dd->unit, idx);
161 		err_info = "receive context";
162 		break;
163 	case IRQ_OTHER:
164 	default:
165 		return -EINVAL;
166 	}
167 	name[sizeof(name) - 1] = 0;
168 
169 	irq = pci_irq_vector(dd->pcidev, nr);
170 	ret = pci_request_irq(dd->pcidev, nr, handler, thread, arg, name);
171 	if (ret) {
172 		dd_dev_err(dd,
173 			   "%s: request for IRQ %d failed, MSIx %d, err %d\n",
174 			   err_info, irq, idx, ret);
175 		spin_lock(&dd->msix_info.msix_lock);
176 		__clear_bit(nr, dd->msix_info.in_use_msix);
177 		spin_unlock(&dd->msix_info.msix_lock);
178 		return ret;
179 	}
180 
181 	/*
182 	 * assign arg after pci_request_irq call, so it will be
183 	 * cleaned up
184 	 */
185 	me = &dd->msix_info.msix_entries[nr];
186 	me->irq = irq;
187 	me->arg = arg;
188 	me->type = type;
189 
190 	/* This is a request, so a failure is not fatal */
191 	ret = hfi1_get_irq_affinity(dd, me);
192 	if (ret)
193 		dd_dev_err(dd, "unable to pin IRQ %d\n", ret);
194 
195 	return nr;
196 }
197 
198 /**
199  * msix_request_rcd_irq() - Helper function for RCVAVAIL IRQs
200  * @rcd: valid rcd context
201  *
202  */
203 int msix_request_rcd_irq(struct hfi1_ctxtdata *rcd)
204 {
205 	int nr;
206 
207 	nr = msix_request_irq(rcd->dd, rcd, receive_context_interrupt,
208 			      receive_context_thread, rcd->ctxt, IRQ_RCVCTXT);
209 	if (nr < 0)
210 		return nr;
211 
212 	/*
213 	 * Set the interrupt register and mask for this
214 	 * context's interrupt.
215 	 */
216 	rcd->ireg = (IS_RCVAVAIL_START + rcd->ctxt) / 64;
217 	rcd->imask = ((u64)1) << ((IS_RCVAVAIL_START + rcd->ctxt) % 64);
218 	rcd->msix_intr = nr;
219 	remap_intr(rcd->dd, IS_RCVAVAIL_START + rcd->ctxt, nr);
220 
221 	return 0;
222 }
223 
224 /**
225  * msix_request_smda_ira() - Helper for getting SDMA IRQ resources
226  * @sde: valid sdma engine
227  *
228  */
229 int msix_request_sdma_irq(struct sdma_engine *sde)
230 {
231 	int nr;
232 
233 	nr = msix_request_irq(sde->dd, sde, sdma_interrupt, NULL,
234 			      sde->this_idx, IRQ_SDMA);
235 	if (nr < 0)
236 		return nr;
237 	sde->msix_intr = nr;
238 	remap_sdma_interrupts(sde->dd, sde->this_idx, nr);
239 
240 	return 0;
241 }
242 
243 /**
244  * enable_sdma_src() - Helper to enable SDMA IRQ srcs
245  * @dd: valid devdata structure
246  * @i: index of SDMA engine
247  */
248 static void enable_sdma_srcs(struct hfi1_devdata *dd, int i)
249 {
250 	set_intr_bits(dd, IS_SDMA_START + i, IS_SDMA_START + i, true);
251 	set_intr_bits(dd, IS_SDMA_PROGRESS_START + i,
252 		      IS_SDMA_PROGRESS_START + i, true);
253 	set_intr_bits(dd, IS_SDMA_IDLE_START + i, IS_SDMA_IDLE_START + i, true);
254 	set_intr_bits(dd, IS_SDMAENG_ERR_START + i, IS_SDMAENG_ERR_START + i,
255 		      true);
256 }
257 
258 /**
259  * msix_request_irqs() - Allocate all MSIx IRQs
260  * @dd: valid devdata structure
261  *
262  * Helper function to request the used MSIx IRQs.
263  *
264  */
265 int msix_request_irqs(struct hfi1_devdata *dd)
266 {
267 	int i;
268 	int ret;
269 
270 	ret = msix_request_irq(dd, dd, general_interrupt, NULL, 0, IRQ_GENERAL);
271 	if (ret < 0)
272 		return ret;
273 
274 	for (i = 0; i < dd->num_sdma; i++) {
275 		struct sdma_engine *sde = &dd->per_sdma[i];
276 
277 		ret = msix_request_sdma_irq(sde);
278 		if (ret)
279 			return ret;
280 		enable_sdma_srcs(sde->dd, i);
281 	}
282 
283 	for (i = 0; i < dd->n_krcv_queues; i++) {
284 		struct hfi1_ctxtdata *rcd = hfi1_rcd_get_by_index_safe(dd, i);
285 
286 		if (rcd)
287 			ret = msix_request_rcd_irq(rcd);
288 		hfi1_rcd_put(rcd);
289 		if (ret)
290 			return ret;
291 	}
292 
293 	return 0;
294 }
295 
296 /**
297  * msix_free_irq() - Free the specified MSIx resources and IRQ
298  * @dd: valid devdata
299  * @msix_intr: MSIx vector to free.
300  *
301  */
302 void msix_free_irq(struct hfi1_devdata *dd, u8 msix_intr)
303 {
304 	struct hfi1_msix_entry *me;
305 
306 	if (msix_intr >= dd->msix_info.max_requested)
307 		return;
308 
309 	me = &dd->msix_info.msix_entries[msix_intr];
310 
311 	if (!me->arg) /* => no irq, no affinity */
312 		return;
313 
314 	hfi1_put_irq_affinity(dd, me);
315 	pci_free_irq(dd->pcidev, msix_intr, me->arg);
316 
317 	me->arg = NULL;
318 
319 	spin_lock(&dd->msix_info.msix_lock);
320 	__clear_bit(msix_intr, dd->msix_info.in_use_msix);
321 	spin_unlock(&dd->msix_info.msix_lock);
322 }
323 
324 /**
325  * hfi1_clean_up_msix_interrupts() - Free all MSIx IRQ resources
326  * @dd: valid device data data structure
327  *
328  * Free the MSIx and associated PCI resources, if they have been allocated.
329  */
330 void msix_clean_up_interrupts(struct hfi1_devdata *dd)
331 {
332 	int i;
333 	struct hfi1_msix_entry *me = dd->msix_info.msix_entries;
334 
335 	/* remove irqs - must happen before disabling/turning off */
336 	for (i = 0; i < dd->msix_info.max_requested; i++, me++)
337 		msix_free_irq(dd, i);
338 
339 	/* clean structures */
340 	kfree(dd->msix_info.msix_entries);
341 	dd->msix_info.msix_entries = NULL;
342 	dd->msix_info.max_requested = 0;
343 
344 	pci_free_irq_vectors(dd->pcidev);
345 }
346 
347 /**
348  * msix_vnic_syncrhonize_irq() - Vnic IRQ synchronize
349  * @dd: valid devdata
350  */
351 void msix_vnic_synchronize_irq(struct hfi1_devdata *dd)
352 {
353 	int i;
354 
355 	for (i = 0; i < dd->vnic.num_ctxt; i++) {
356 		struct hfi1_ctxtdata *rcd = dd->vnic.ctxt[i];
357 		struct hfi1_msix_entry *me;
358 
359 		me = &dd->msix_info.msix_entries[rcd->msix_intr];
360 
361 		synchronize_irq(me->irq);
362 	}
363 }
364