xref: /openbmc/linux/drivers/infiniband/hw/hfi1/msix.c (revision 2cf1c348)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3  * Copyright(c) 2018 - 2020 Intel Corporation.
4  */
5 
6 #include "hfi.h"
7 #include "affinity.h"
8 #include "sdma.h"
9 #include "netdev.h"
10 
11 /**
12  * msix_initialize() - Calculate, request and configure MSIx IRQs
13  * @dd: valid hfi1 devdata
14  *
15  */
16 int msix_initialize(struct hfi1_devdata *dd)
17 {
18 	u32 total;
19 	int ret;
20 	struct hfi1_msix_entry *entries;
21 
22 	/*
23 	 * MSIx interrupt count:
24 	 *	one for the general, "slow path" interrupt
25 	 *	one per used SDMA engine
26 	 *	one per kernel receive context
27 	 *	one for each VNIC context
28 	 *      ...any new IRQs should be added here.
29 	 */
30 	total = 1 + dd->num_sdma + dd->n_krcv_queues + dd->num_netdev_contexts;
31 
32 	if (total >= CCE_NUM_MSIX_VECTORS)
33 		return -EINVAL;
34 
35 	ret = pci_alloc_irq_vectors(dd->pcidev, total, total, PCI_IRQ_MSIX);
36 	if (ret < 0) {
37 		dd_dev_err(dd, "pci_alloc_irq_vectors() failed: %d\n", ret);
38 		return ret;
39 	}
40 
41 	entries = kcalloc(total, sizeof(*dd->msix_info.msix_entries),
42 			  GFP_KERNEL);
43 	if (!entries) {
44 		pci_free_irq_vectors(dd->pcidev);
45 		return -ENOMEM;
46 	}
47 
48 	dd->msix_info.msix_entries = entries;
49 	spin_lock_init(&dd->msix_info.msix_lock);
50 	bitmap_zero(dd->msix_info.in_use_msix, total);
51 	dd->msix_info.max_requested = total;
52 	dd_dev_info(dd, "%u MSI-X interrupts allocated\n", total);
53 
54 	return 0;
55 }
56 
57 /**
58  * msix_request_irq() - Allocate a free MSIx IRQ
59  * @dd: valid devdata
60  * @arg: context information for the IRQ
61  * @handler: IRQ handler
62  * @thread: IRQ thread handler (could be NULL)
63  * @type: affinty IRQ type
64  * @name: IRQ name
65  *
66  * Allocated an MSIx vector if available, and then create the appropriate
67  * meta data needed to keep track of the pci IRQ request.
68  *
69  * Return:
70  *   < 0   Error
71  *   >= 0  MSIx vector
72  *
73  */
74 static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
75 			    irq_handler_t handler, irq_handler_t thread,
76 			    enum irq_type type, const char *name)
77 {
78 	unsigned long nr;
79 	int irq;
80 	int ret;
81 	struct hfi1_msix_entry *me;
82 
83 	/* Allocate an MSIx vector */
84 	spin_lock(&dd->msix_info.msix_lock);
85 	nr = find_first_zero_bit(dd->msix_info.in_use_msix,
86 				 dd->msix_info.max_requested);
87 	if (nr < dd->msix_info.max_requested)
88 		__set_bit(nr, dd->msix_info.in_use_msix);
89 	spin_unlock(&dd->msix_info.msix_lock);
90 
91 	if (nr == dd->msix_info.max_requested)
92 		return -ENOSPC;
93 
94 	if (type < IRQ_SDMA || type >= IRQ_OTHER)
95 		return -EINVAL;
96 
97 	irq = pci_irq_vector(dd->pcidev, nr);
98 	ret = pci_request_irq(dd->pcidev, nr, handler, thread, arg, name);
99 	if (ret) {
100 		dd_dev_err(dd,
101 			   "%s: request for IRQ %d failed, MSIx %lx, err %d\n",
102 			   name, irq, nr, ret);
103 		spin_lock(&dd->msix_info.msix_lock);
104 		__clear_bit(nr, dd->msix_info.in_use_msix);
105 		spin_unlock(&dd->msix_info.msix_lock);
106 		return ret;
107 	}
108 
109 	/*
110 	 * assign arg after pci_request_irq call, so it will be
111 	 * cleaned up
112 	 */
113 	me = &dd->msix_info.msix_entries[nr];
114 	me->irq = irq;
115 	me->arg = arg;
116 	me->type = type;
117 
118 	/* This is a request, so a failure is not fatal */
119 	ret = hfi1_get_irq_affinity(dd, me);
120 	if (ret)
121 		dd_dev_err(dd, "%s: unable to pin IRQ %d\n", name, ret);
122 
123 	return nr;
124 }
125 
126 static int msix_request_rcd_irq_common(struct hfi1_ctxtdata *rcd,
127 				       irq_handler_t handler,
128 				       irq_handler_t thread,
129 				       const char *name)
130 {
131 	int nr = msix_request_irq(rcd->dd, rcd, handler, thread,
132 				  rcd->is_vnic ? IRQ_NETDEVCTXT : IRQ_RCVCTXT,
133 				  name);
134 	if (nr < 0)
135 		return nr;
136 
137 	/*
138 	 * Set the interrupt register and mask for this
139 	 * context's interrupt.
140 	 */
141 	rcd->ireg = (IS_RCVAVAIL_START + rcd->ctxt) / 64;
142 	rcd->imask = ((u64)1) << ((IS_RCVAVAIL_START + rcd->ctxt) % 64);
143 	rcd->msix_intr = nr;
144 	remap_intr(rcd->dd, IS_RCVAVAIL_START + rcd->ctxt, nr);
145 
146 	return 0;
147 }
148 
149 /**
150  * msix_request_rcd_irq() - Helper function for RCVAVAIL IRQs
151  * @rcd: valid rcd context
152  *
153  */
154 int msix_request_rcd_irq(struct hfi1_ctxtdata *rcd)
155 {
156 	char name[MAX_NAME_SIZE];
157 
158 	snprintf(name, sizeof(name), DRIVER_NAME "_%d kctxt%d",
159 		 rcd->dd->unit, rcd->ctxt);
160 
161 	return msix_request_rcd_irq_common(rcd, receive_context_interrupt,
162 					   receive_context_thread, name);
163 }
164 
165 /**
166  * msix_netdev_request_rcd_irq  - Helper function for RCVAVAIL IRQs
167  * for netdev context
168  * @rcd: valid netdev contexti
169  */
170 int msix_netdev_request_rcd_irq(struct hfi1_ctxtdata *rcd)
171 {
172 	char name[MAX_NAME_SIZE];
173 
174 	snprintf(name, sizeof(name), DRIVER_NAME "_%d nd kctxt%d",
175 		 rcd->dd->unit, rcd->ctxt);
176 	return msix_request_rcd_irq_common(rcd, receive_context_interrupt_napi,
177 					   NULL, name);
178 }
179 
180 /**
181  * msix_request_sdma_irq  - Helper for getting SDMA IRQ resources
182  * @sde: valid sdma engine
183  *
184  */
185 int msix_request_sdma_irq(struct sdma_engine *sde)
186 {
187 	int nr;
188 	char name[MAX_NAME_SIZE];
189 
190 	snprintf(name, sizeof(name), DRIVER_NAME "_%d sdma%d",
191 		 sde->dd->unit, sde->this_idx);
192 	nr = msix_request_irq(sde->dd, sde, sdma_interrupt, NULL,
193 			      IRQ_SDMA, name);
194 	if (nr < 0)
195 		return nr;
196 	sde->msix_intr = nr;
197 	remap_sdma_interrupts(sde->dd, sde->this_idx, nr);
198 
199 	return 0;
200 }
201 
202 /**
203  * msix_request_general_irq - Helper for getting general IRQ
204  * resources
205  * @dd: valid device data
206  */
207 int msix_request_general_irq(struct hfi1_devdata *dd)
208 {
209 	int nr;
210 	char name[MAX_NAME_SIZE];
211 
212 	snprintf(name, sizeof(name), DRIVER_NAME "_%d", dd->unit);
213 	nr = msix_request_irq(dd, dd, general_interrupt, NULL, IRQ_GENERAL,
214 			      name);
215 	if (nr < 0)
216 		return nr;
217 
218 	/* general interrupt must be MSIx vector 0 */
219 	if (nr) {
220 		msix_free_irq(dd, (u8)nr);
221 		dd_dev_err(dd, "Invalid index %d for GENERAL IRQ\n", nr);
222 		return -EINVAL;
223 	}
224 
225 	return 0;
226 }
227 
228 /**
229  * enable_sdma_srcs - Helper to enable SDMA IRQ srcs
230  * @dd: valid devdata structure
231  * @i: index of SDMA engine
232  */
233 static void enable_sdma_srcs(struct hfi1_devdata *dd, int i)
234 {
235 	set_intr_bits(dd, IS_SDMA_START + i, IS_SDMA_START + i, true);
236 	set_intr_bits(dd, IS_SDMA_PROGRESS_START + i,
237 		      IS_SDMA_PROGRESS_START + i, true);
238 	set_intr_bits(dd, IS_SDMA_IDLE_START + i, IS_SDMA_IDLE_START + i, true);
239 	set_intr_bits(dd, IS_SDMAENG_ERR_START + i, IS_SDMAENG_ERR_START + i,
240 		      true);
241 }
242 
243 /**
244  * msix_request_irqs() - Allocate all MSIx IRQs
245  * @dd: valid devdata structure
246  *
247  * Helper function to request the used MSIx IRQs.
248  *
249  */
250 int msix_request_irqs(struct hfi1_devdata *dd)
251 {
252 	int i;
253 	int ret = msix_request_general_irq(dd);
254 
255 	if (ret)
256 		return ret;
257 
258 	for (i = 0; i < dd->num_sdma; i++) {
259 		struct sdma_engine *sde = &dd->per_sdma[i];
260 
261 		ret = msix_request_sdma_irq(sde);
262 		if (ret)
263 			return ret;
264 		enable_sdma_srcs(sde->dd, i);
265 	}
266 
267 	for (i = 0; i < dd->n_krcv_queues; i++) {
268 		struct hfi1_ctxtdata *rcd = hfi1_rcd_get_by_index_safe(dd, i);
269 
270 		if (rcd)
271 			ret = msix_request_rcd_irq(rcd);
272 		hfi1_rcd_put(rcd);
273 		if (ret)
274 			return ret;
275 	}
276 
277 	return 0;
278 }
279 
280 /**
281  * msix_free_irq() - Free the specified MSIx resources and IRQ
282  * @dd: valid devdata
283  * @msix_intr: MSIx vector to free.
284  *
285  */
286 void msix_free_irq(struct hfi1_devdata *dd, u8 msix_intr)
287 {
288 	struct hfi1_msix_entry *me;
289 
290 	if (msix_intr >= dd->msix_info.max_requested)
291 		return;
292 
293 	me = &dd->msix_info.msix_entries[msix_intr];
294 
295 	if (!me->arg) /* => no irq, no affinity */
296 		return;
297 
298 	hfi1_put_irq_affinity(dd, me);
299 	pci_free_irq(dd->pcidev, msix_intr, me->arg);
300 
301 	me->arg = NULL;
302 
303 	spin_lock(&dd->msix_info.msix_lock);
304 	__clear_bit(msix_intr, dd->msix_info.in_use_msix);
305 	spin_unlock(&dd->msix_info.msix_lock);
306 }
307 
308 /**
309  * msix_clean_up_interrupts  - Free all MSIx IRQ resources
310  * @dd: valid device data data structure
311  *
312  * Free the MSIx and associated PCI resources, if they have been allocated.
313  */
314 void msix_clean_up_interrupts(struct hfi1_devdata *dd)
315 {
316 	int i;
317 	struct hfi1_msix_entry *me = dd->msix_info.msix_entries;
318 
319 	/* remove irqs - must happen before disabling/turning off */
320 	for (i = 0; i < dd->msix_info.max_requested; i++, me++)
321 		msix_free_irq(dd, i);
322 
323 	/* clean structures */
324 	kfree(dd->msix_info.msix_entries);
325 	dd->msix_info.msix_entries = NULL;
326 	dd->msix_info.max_requested = 0;
327 
328 	pci_free_irq_vectors(dd->pcidev);
329 }
330 
331 /**
332  * msix_netdev_synchronize_irq - netdev IRQ synchronize
333  * @dd: valid devdata
334  */
335 void msix_netdev_synchronize_irq(struct hfi1_devdata *dd)
336 {
337 	int i;
338 	int ctxt_count = hfi1_netdev_ctxt_count(dd);
339 
340 	for (i = 0; i < ctxt_count; i++) {
341 		struct hfi1_ctxtdata *rcd = hfi1_netdev_get_ctxt(dd, i);
342 		struct hfi1_msix_entry *me;
343 
344 		me = &dd->msix_info.msix_entries[rcd->msix_intr];
345 
346 		synchronize_irq(me->irq);
347 	}
348 }
349