xref: /openbmc/linux/drivers/infiniband/hw/hfi1/msix.c (revision 2985bed6)
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 			    enum irq_type type, const char *name)
119 {
120 	unsigned long nr;
121 	int irq;
122 	int ret;
123 	struct hfi1_msix_entry *me;
124 
125 	/* Allocate an MSIx vector */
126 	spin_lock(&dd->msix_info.msix_lock);
127 	nr = find_first_zero_bit(dd->msix_info.in_use_msix,
128 				 dd->msix_info.max_requested);
129 	if (nr < dd->msix_info.max_requested)
130 		__set_bit(nr, dd->msix_info.in_use_msix);
131 	spin_unlock(&dd->msix_info.msix_lock);
132 
133 	if (nr == dd->msix_info.max_requested)
134 		return -ENOSPC;
135 
136 	if (type < IRQ_SDMA || type >= IRQ_OTHER)
137 		return -EINVAL;
138 
139 	irq = pci_irq_vector(dd->pcidev, nr);
140 	ret = pci_request_irq(dd->pcidev, nr, handler, thread, arg, name);
141 	if (ret) {
142 		dd_dev_err(dd,
143 			   "%s: request for IRQ %d failed, MSIx %lu, err %d\n",
144 			   name, irq, nr, ret);
145 		spin_lock(&dd->msix_info.msix_lock);
146 		__clear_bit(nr, dd->msix_info.in_use_msix);
147 		spin_unlock(&dd->msix_info.msix_lock);
148 		return ret;
149 	}
150 
151 	/*
152 	 * assign arg after pci_request_irq call, so it will be
153 	 * cleaned up
154 	 */
155 	me = &dd->msix_info.msix_entries[nr];
156 	me->irq = irq;
157 	me->arg = arg;
158 	me->type = type;
159 
160 	/* This is a request, so a failure is not fatal */
161 	ret = hfi1_get_irq_affinity(dd, me);
162 	if (ret)
163 		dd_dev_err(dd, "unable to pin IRQ %d\n", ret);
164 
165 	return nr;
166 }
167 
168 static int msix_request_rcd_irq_common(struct hfi1_ctxtdata *rcd,
169 				       irq_handler_t handler,
170 				       irq_handler_t thread,
171 				       const char *name)
172 {
173 	int nr = msix_request_irq(rcd->dd, rcd, handler, thread,
174 				  IRQ_RCVCTXT, name);
175 	if (nr < 0)
176 		return nr;
177 
178 	/*
179 	 * Set the interrupt register and mask for this
180 	 * context's interrupt.
181 	 */
182 	rcd->ireg = (IS_RCVAVAIL_START + rcd->ctxt) / 64;
183 	rcd->imask = ((u64)1) << ((IS_RCVAVAIL_START + rcd->ctxt) % 64);
184 	rcd->msix_intr = nr;
185 	remap_intr(rcd->dd, IS_RCVAVAIL_START + rcd->ctxt, nr);
186 
187 	return 0;
188 }
189 
190 /**
191  * msix_request_rcd_irq() - Helper function for RCVAVAIL IRQs
192  * @rcd: valid rcd context
193  *
194  */
195 int msix_request_rcd_irq(struct hfi1_ctxtdata *rcd)
196 {
197 	char name[MAX_NAME_SIZE];
198 
199 	snprintf(name, sizeof(name), DRIVER_NAME "_%d kctxt%d",
200 		 rcd->dd->unit, rcd->ctxt);
201 
202 	return msix_request_rcd_irq_common(rcd, receive_context_interrupt,
203 					   receive_context_thread, name);
204 }
205 
206 /**
207  * msix_request_smda_ira() - Helper for getting SDMA IRQ resources
208  * @sde: valid sdma engine
209  *
210  */
211 int msix_request_sdma_irq(struct sdma_engine *sde)
212 {
213 	int nr;
214 	char name[MAX_NAME_SIZE];
215 
216 	snprintf(name, sizeof(name), DRIVER_NAME "_%d sdma%d",
217 		 sde->dd->unit, sde->this_idx);
218 	nr = msix_request_irq(sde->dd, sde, sdma_interrupt, NULL,
219 			      IRQ_SDMA, name);
220 	if (nr < 0)
221 		return nr;
222 	sde->msix_intr = nr;
223 	remap_sdma_interrupts(sde->dd, sde->this_idx, nr);
224 
225 	return 0;
226 }
227 
228 /**
229  * msix_request_general_irq(void) - Helper for getting general IRQ
230  * resources
231  * @dd: valid device data
232  */
233 int msix_request_general_irq(struct hfi1_devdata *dd)
234 {
235 	int nr;
236 	char name[MAX_NAME_SIZE];
237 
238 	snprintf(name, sizeof(name), DRIVER_NAME "_%d", dd->unit);
239 	nr = msix_request_irq(dd, dd, general_interrupt, NULL, IRQ_GENERAL,
240 			      name);
241 	if (nr < 0)
242 		return nr;
243 
244 	/* general interrupt must be MSIx vector 0 */
245 	if (nr) {
246 		msix_free_irq(dd, (u8)nr);
247 		dd_dev_err(dd, "Invalid index %d for GENERAL IRQ\n", nr);
248 		return -EINVAL;
249 	}
250 
251 	return 0;
252 }
253 
254 /**
255  * enable_sdma_src() - Helper to enable SDMA IRQ srcs
256  * @dd: valid devdata structure
257  * @i: index of SDMA engine
258  */
259 static void enable_sdma_srcs(struct hfi1_devdata *dd, int i)
260 {
261 	set_intr_bits(dd, IS_SDMA_START + i, IS_SDMA_START + i, true);
262 	set_intr_bits(dd, IS_SDMA_PROGRESS_START + i,
263 		      IS_SDMA_PROGRESS_START + i, true);
264 	set_intr_bits(dd, IS_SDMA_IDLE_START + i, IS_SDMA_IDLE_START + i, true);
265 	set_intr_bits(dd, IS_SDMAENG_ERR_START + i, IS_SDMAENG_ERR_START + i,
266 		      true);
267 }
268 
269 /**
270  * msix_request_irqs() - Allocate all MSIx IRQs
271  * @dd: valid devdata structure
272  *
273  * Helper function to request the used MSIx IRQs.
274  *
275  */
276 int msix_request_irqs(struct hfi1_devdata *dd)
277 {
278 	int i;
279 	int ret = msix_request_general_irq(dd);
280 
281 	if (ret)
282 		return ret;
283 
284 	for (i = 0; i < dd->num_sdma; i++) {
285 		struct sdma_engine *sde = &dd->per_sdma[i];
286 
287 		ret = msix_request_sdma_irq(sde);
288 		if (ret)
289 			return ret;
290 		enable_sdma_srcs(sde->dd, i);
291 	}
292 
293 	for (i = 0; i < dd->n_krcv_queues; i++) {
294 		struct hfi1_ctxtdata *rcd = hfi1_rcd_get_by_index_safe(dd, i);
295 
296 		if (rcd)
297 			ret = msix_request_rcd_irq(rcd);
298 		hfi1_rcd_put(rcd);
299 		if (ret)
300 			return ret;
301 	}
302 
303 	return 0;
304 }
305 
306 /**
307  * msix_free_irq() - Free the specified MSIx resources and IRQ
308  * @dd: valid devdata
309  * @msix_intr: MSIx vector to free.
310  *
311  */
312 void msix_free_irq(struct hfi1_devdata *dd, u8 msix_intr)
313 {
314 	struct hfi1_msix_entry *me;
315 
316 	if (msix_intr >= dd->msix_info.max_requested)
317 		return;
318 
319 	me = &dd->msix_info.msix_entries[msix_intr];
320 
321 	if (!me->arg) /* => no irq, no affinity */
322 		return;
323 
324 	hfi1_put_irq_affinity(dd, me);
325 	pci_free_irq(dd->pcidev, msix_intr, me->arg);
326 
327 	me->arg = NULL;
328 
329 	spin_lock(&dd->msix_info.msix_lock);
330 	__clear_bit(msix_intr, dd->msix_info.in_use_msix);
331 	spin_unlock(&dd->msix_info.msix_lock);
332 }
333 
334 /**
335  * hfi1_clean_up_msix_interrupts() - Free all MSIx IRQ resources
336  * @dd: valid device data data structure
337  *
338  * Free the MSIx and associated PCI resources, if they have been allocated.
339  */
340 void msix_clean_up_interrupts(struct hfi1_devdata *dd)
341 {
342 	int i;
343 	struct hfi1_msix_entry *me = dd->msix_info.msix_entries;
344 
345 	/* remove irqs - must happen before disabling/turning off */
346 	for (i = 0; i < dd->msix_info.max_requested; i++, me++)
347 		msix_free_irq(dd, i);
348 
349 	/* clean structures */
350 	kfree(dd->msix_info.msix_entries);
351 	dd->msix_info.msix_entries = NULL;
352 	dd->msix_info.max_requested = 0;
353 
354 	pci_free_irq_vectors(dd->pcidev);
355 }
356 
357 /**
358  * msix_vnic_syncrhonize_irq() - Vnic IRQ synchronize
359  * @dd: valid devdata
360  */
361 void msix_vnic_synchronize_irq(struct hfi1_devdata *dd)
362 {
363 	int i;
364 
365 	for (i = 0; i < dd->vnic.num_ctxt; i++) {
366 		struct hfi1_ctxtdata *rcd = dd->vnic.ctxt[i];
367 		struct hfi1_msix_entry *me;
368 
369 		me = &dd->msix_info.msix_entries[rcd->msix_intr];
370 
371 		synchronize_irq(me->irq);
372 	}
373 }
374