1 // SPDX-License-Identifier: GPL-2.0
2 /* pci_msi.c: Sparc64 MSI support common layer.
3 *
4 * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
5 */
6 #include <linux/kernel.h>
7 #include <linux/interrupt.h>
8 #include <linux/of.h>
9 #include <linux/platform_device.h>
10 #include <linux/slab.h>
11 #include <linux/irq.h>
12
13 #include "pci_impl.h"
14
15 static irqreturn_t sparc64_msiq_interrupt(int irq, void *cookie)
16 {
17 struct sparc64_msiq_cookie *msiq_cookie = cookie;
18 struct pci_pbm_info *pbm = msiq_cookie->pbm;
19 unsigned long msiqid = msiq_cookie->msiqid;
20 const struct sparc64_msiq_ops *ops;
21 unsigned long orig_head, head;
22 int err;
23
24 ops = pbm->msi_ops;
25
26 err = ops->get_head(pbm, msiqid, &head);
27 if (unlikely(err < 0))
28 goto err_get_head;
29
30 orig_head = head;
31 for (;;) {
32 unsigned long msi;
33
34 err = ops->dequeue_msi(pbm, msiqid, &head, &msi);
35 if (likely(err > 0)) {
36 unsigned int irq;
37
38 irq = pbm->msi_irq_table[msi - pbm->msi_first];
39 generic_handle_irq(irq);
40 }
41
42 if (unlikely(err < 0))
43 goto err_dequeue;
44
45 if (err == 0)
46 break;
47 }
48 if (likely(head != orig_head)) {
49 err = ops->set_head(pbm, msiqid, head);
50 if (unlikely(err < 0))
51 goto err_set_head;
52 }
53 return IRQ_HANDLED;
54
55 err_get_head:
56 printk(KERN_EMERG "MSI: Get head on msiqid[%lu] gives error %d\n",
57 msiqid, err);
58 goto err_out;
59
60 err_dequeue:
61 printk(KERN_EMERG "MSI: Dequeue head[%lu] from msiqid[%lu] "
62 "gives error %d\n",
63 head, msiqid, err);
64 goto err_out;
65
66 err_set_head:
67 printk(KERN_EMERG "MSI: Set head[%lu] on msiqid[%lu] "
68 "gives error %d\n",
69 head, msiqid, err);
70 goto err_out;
71
72 err_out:
73 return IRQ_NONE;
74 }
75
76 static u32 pick_msiq(struct pci_pbm_info *pbm)
77 {
78 static DEFINE_SPINLOCK(rotor_lock);
79 unsigned long flags;
80 u32 ret, rotor;
81
82 spin_lock_irqsave(&rotor_lock, flags);
83
84 rotor = pbm->msiq_rotor;
85 ret = pbm->msiq_first + rotor;
86
87 if (++rotor >= pbm->msiq_num)
88 rotor = 0;
89 pbm->msiq_rotor = rotor;
90
91 spin_unlock_irqrestore(&rotor_lock, flags);
92
93 return ret;
94 }
95
96
97 static int alloc_msi(struct pci_pbm_info *pbm)
98 {
99 int i;
100
101 for (i = 0; i < pbm->msi_num; i++) {
102 if (!test_and_set_bit(i, pbm->msi_bitmap))
103 return i + pbm->msi_first;
104 }
105
106 return -ENOENT;
107 }
108
109 static void free_msi(struct pci_pbm_info *pbm, int msi_num)
110 {
111 msi_num -= pbm->msi_first;
112 clear_bit(msi_num, pbm->msi_bitmap);
113 }
114
115 static struct irq_chip msi_irq = {
116 .name = "PCI-MSI",
117 .irq_mask = pci_msi_mask_irq,
118 .irq_unmask = pci_msi_unmask_irq,
119 .irq_enable = pci_msi_unmask_irq,
120 .irq_disable = pci_msi_mask_irq,
121 /* XXX affinity XXX */
122 };
123
124 static int sparc64_setup_msi_irq(unsigned int *irq_p,
125 struct pci_dev *pdev,
126 struct msi_desc *entry)
127 {
128 struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
129 const struct sparc64_msiq_ops *ops = pbm->msi_ops;
130 struct msi_msg msg;
131 int msi, err;
132 u32 msiqid;
133
134 *irq_p = irq_alloc(0, 0);
135 err = -ENOMEM;
136 if (!*irq_p)
137 goto out_err;
138
139 irq_set_chip_and_handler_name(*irq_p, &msi_irq, handle_simple_irq,
140 "MSI");
141
142 err = alloc_msi(pbm);
143 if (unlikely(err < 0))
144 goto out_irq_free;
145
146 msi = err;
147
148 msiqid = pick_msiq(pbm);
149
150 err = ops->msi_setup(pbm, msiqid, msi,
151 (entry->pci.msi_attrib.is_64 ? 1 : 0));
152 if (err)
153 goto out_msi_free;
154
155 pbm->msi_irq_table[msi - pbm->msi_first] = *irq_p;
156
157 if (entry->pci.msi_attrib.is_64) {
158 msg.address_hi = pbm->msi64_start >> 32;
159 msg.address_lo = pbm->msi64_start & 0xffffffff;
160 } else {
161 msg.address_hi = 0;
162 msg.address_lo = pbm->msi32_start;
163 }
164 msg.data = msi;
165
166 irq_set_msi_desc(*irq_p, entry);
167 pci_write_msi_msg(*irq_p, &msg);
168
169 return 0;
170
171 out_msi_free:
172 free_msi(pbm, msi);
173
174 out_irq_free:
175 irq_set_chip(*irq_p, NULL);
176 irq_free(*irq_p);
177 *irq_p = 0;
178
179 out_err:
180 return err;
181 }
182
183 static void sparc64_teardown_msi_irq(unsigned int irq,
184 struct pci_dev *pdev)
185 {
186 struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
187 const struct sparc64_msiq_ops *ops = pbm->msi_ops;
188 unsigned int msi_num;
189 int i, err;
190
191 for (i = 0; i < pbm->msi_num; i++) {
192 if (pbm->msi_irq_table[i] == irq)
193 break;
194 }
195 if (i >= pbm->msi_num) {
196 pci_err(pdev, "%s: teardown: No MSI for irq %u\n", pbm->name,
197 irq);
198 return;
199 }
200
201 msi_num = pbm->msi_first + i;
202 pbm->msi_irq_table[i] = ~0U;
203
204 err = ops->msi_teardown(pbm, msi_num);
205 if (err) {
206 pci_err(pdev, "%s: teardown: ops->teardown() on MSI %u, "
207 "irq %u, gives error %d\n", pbm->name, msi_num, irq,
208 err);
209 return;
210 }
211
212 free_msi(pbm, msi_num);
213
214 irq_set_chip(irq, NULL);
215 irq_free(irq);
216 }
217
218 static int msi_bitmap_alloc(struct pci_pbm_info *pbm)
219 {
220 unsigned long size, bits_per_ulong;
221
222 bits_per_ulong = sizeof(unsigned long) * 8;
223 size = (pbm->msi_num + (bits_per_ulong - 1)) & ~(bits_per_ulong - 1);
224 size /= 8;
225 BUG_ON(size % sizeof(unsigned long));
226
227 pbm->msi_bitmap = kzalloc(size, GFP_KERNEL);
228 if (!pbm->msi_bitmap)
229 return -ENOMEM;
230
231 return 0;
232 }
233
234 static void msi_bitmap_free(struct pci_pbm_info *pbm)
235 {
236 kfree(pbm->msi_bitmap);
237 pbm->msi_bitmap = NULL;
238 }
239
240 static int msi_table_alloc(struct pci_pbm_info *pbm)
241 {
242 int size, i;
243
244 size = pbm->msiq_num * sizeof(struct sparc64_msiq_cookie);
245 pbm->msiq_irq_cookies = kzalloc(size, GFP_KERNEL);
246 if (!pbm->msiq_irq_cookies)
247 return -ENOMEM;
248
249 for (i = 0; i < pbm->msiq_num; i++) {
250 struct sparc64_msiq_cookie *p;
251
252 p = &pbm->msiq_irq_cookies[i];
253 p->pbm = pbm;
254 p->msiqid = pbm->msiq_first + i;
255 }
256
257 size = pbm->msi_num * sizeof(unsigned int);
258 pbm->msi_irq_table = kzalloc(size, GFP_KERNEL);
259 if (!pbm->msi_irq_table) {
260 kfree(pbm->msiq_irq_cookies);
261 pbm->msiq_irq_cookies = NULL;
262 return -ENOMEM;
263 }
264
265 return 0;
266 }
267
268 static void msi_table_free(struct pci_pbm_info *pbm)
269 {
270 kfree(pbm->msiq_irq_cookies);
271 pbm->msiq_irq_cookies = NULL;
272
273 kfree(pbm->msi_irq_table);
274 pbm->msi_irq_table = NULL;
275 }
276
277 static int bringup_one_msi_queue(struct pci_pbm_info *pbm,
278 const struct sparc64_msiq_ops *ops,
279 unsigned long msiqid,
280 unsigned long devino)
281 {
282 int irq = ops->msiq_build_irq(pbm, msiqid, devino);
283 int err, nid;
284
285 if (irq < 0)
286 return irq;
287
288 nid = pbm->numa_node;
289 if (nid != -1) {
290 irq_set_affinity(irq, cpumask_of_node(nid));
291 }
292 err = request_irq(irq, sparc64_msiq_interrupt, 0,
293 "MSIQ",
294 &pbm->msiq_irq_cookies[msiqid - pbm->msiq_first]);
295 if (err)
296 return err;
297
298 return 0;
299 }
300
301 static int sparc64_bringup_msi_queues(struct pci_pbm_info *pbm,
302 const struct sparc64_msiq_ops *ops)
303 {
304 int i;
305
306 for (i = 0; i < pbm->msiq_num; i++) {
307 unsigned long msiqid = i + pbm->msiq_first;
308 unsigned long devino = i + pbm->msiq_first_devino;
309 int err;
310
311 err = bringup_one_msi_queue(pbm, ops, msiqid, devino);
312 if (err)
313 return err;
314 }
315
316 return 0;
317 }
318
319 void sparc64_pbm_msi_init(struct pci_pbm_info *pbm,
320 const struct sparc64_msiq_ops *ops)
321 {
322 const u32 *val;
323 int len;
324
325 val = of_get_property(pbm->op->dev.of_node, "#msi-eqs", &len);
326 if (!val || len != 4)
327 goto no_msi;
328 pbm->msiq_num = *val;
329 if (pbm->msiq_num) {
330 const struct msiq_prop {
331 u32 first_msiq;
332 u32 num_msiq;
333 u32 first_devino;
334 } *mqp;
335 const struct msi_range_prop {
336 u32 first_msi;
337 u32 num_msi;
338 } *mrng;
339 const struct addr_range_prop {
340 u32 msi32_high;
341 u32 msi32_low;
342 u32 msi32_len;
343 u32 msi64_high;
344 u32 msi64_low;
345 u32 msi64_len;
346 } *arng;
347
348 val = of_get_property(pbm->op->dev.of_node, "msi-eq-size", &len);
349 if (!val || len != 4)
350 goto no_msi;
351
352 pbm->msiq_ent_count = *val;
353
354 mqp = of_get_property(pbm->op->dev.of_node,
355 "msi-eq-to-devino", &len);
356 if (!mqp)
357 mqp = of_get_property(pbm->op->dev.of_node,
358 "msi-eq-devino", &len);
359 if (!mqp || len != sizeof(struct msiq_prop))
360 goto no_msi;
361
362 pbm->msiq_first = mqp->first_msiq;
363 pbm->msiq_first_devino = mqp->first_devino;
364
365 val = of_get_property(pbm->op->dev.of_node, "#msi", &len);
366 if (!val || len != 4)
367 goto no_msi;
368 pbm->msi_num = *val;
369
370 mrng = of_get_property(pbm->op->dev.of_node, "msi-ranges", &len);
371 if (!mrng || len != sizeof(struct msi_range_prop))
372 goto no_msi;
373 pbm->msi_first = mrng->first_msi;
374
375 val = of_get_property(pbm->op->dev.of_node, "msi-data-mask", &len);
376 if (!val || len != 4)
377 goto no_msi;
378 pbm->msi_data_mask = *val;
379
380 val = of_get_property(pbm->op->dev.of_node, "msix-data-width", &len);
381 if (!val || len != 4)
382 goto no_msi;
383 pbm->msix_data_width = *val;
384
385 arng = of_get_property(pbm->op->dev.of_node, "msi-address-ranges",
386 &len);
387 if (!arng || len != sizeof(struct addr_range_prop))
388 goto no_msi;
389 pbm->msi32_start = ((u64)arng->msi32_high << 32) |
390 (u64) arng->msi32_low;
391 pbm->msi64_start = ((u64)arng->msi64_high << 32) |
392 (u64) arng->msi64_low;
393 pbm->msi32_len = arng->msi32_len;
394 pbm->msi64_len = arng->msi64_len;
395
396 if (msi_bitmap_alloc(pbm))
397 goto no_msi;
398
399 if (msi_table_alloc(pbm)) {
400 msi_bitmap_free(pbm);
401 goto no_msi;
402 }
403
404 if (ops->msiq_alloc(pbm)) {
405 msi_table_free(pbm);
406 msi_bitmap_free(pbm);
407 goto no_msi;
408 }
409
410 if (sparc64_bringup_msi_queues(pbm, ops)) {
411 ops->msiq_free(pbm);
412 msi_table_free(pbm);
413 msi_bitmap_free(pbm);
414 goto no_msi;
415 }
416
417 printk(KERN_INFO "%s: MSI Queue first[%u] num[%u] count[%u] "
418 "devino[0x%x]\n",
419 pbm->name,
420 pbm->msiq_first, pbm->msiq_num,
421 pbm->msiq_ent_count,
422 pbm->msiq_first_devino);
423 printk(KERN_INFO "%s: MSI first[%u] num[%u] mask[0x%x] "
424 "width[%u]\n",
425 pbm->name,
426 pbm->msi_first, pbm->msi_num, pbm->msi_data_mask,
427 pbm->msix_data_width);
428 printk(KERN_INFO "%s: MSI addr32[0x%llx:0x%x] "
429 "addr64[0x%llx:0x%x]\n",
430 pbm->name,
431 pbm->msi32_start, pbm->msi32_len,
432 pbm->msi64_start, pbm->msi64_len);
433 printk(KERN_INFO "%s: MSI queues at RA [%016lx]\n",
434 pbm->name,
435 __pa(pbm->msi_queues));
436
437 pbm->msi_ops = ops;
438 pbm->setup_msi_irq = sparc64_setup_msi_irq;
439 pbm->teardown_msi_irq = sparc64_teardown_msi_irq;
440 }
441 return;
442
443 no_msi:
444 pbm->msiq_num = 0;
445 printk(KERN_INFO "%s: No MSI support.\n", pbm->name);
446 }
447
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