Commit | Line | Data |
---|---|---|
3bc2b234 RJ |
1 | /* |
2 | * Copyright (C) 2015 Broadcom Corporation | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License as | |
6 | * published by the Free Software Foundation version 2. | |
7 | * | |
8 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
9 | * kind, whether express or implied; without even the implied warranty | |
10 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | */ | |
13 | ||
14 | #include <linux/interrupt.h> | |
15 | #include <linux/irqchip/chained_irq.h> | |
16 | #include <linux/irqdomain.h> | |
17 | #include <linux/msi.h> | |
18 | #include <linux/of_irq.h> | |
19 | #include <linux/of_pci.h> | |
20 | #include <linux/pci.h> | |
21 | ||
22 | #include "pcie-iproc.h" | |
23 | ||
24 | #define IPROC_MSI_INTR_EN_SHIFT 11 | |
25 | #define IPROC_MSI_INTR_EN BIT(IPROC_MSI_INTR_EN_SHIFT) | |
26 | #define IPROC_MSI_INT_N_EVENT_SHIFT 1 | |
27 | #define IPROC_MSI_INT_N_EVENT BIT(IPROC_MSI_INT_N_EVENT_SHIFT) | |
28 | #define IPROC_MSI_EQ_EN_SHIFT 0 | |
29 | #define IPROC_MSI_EQ_EN BIT(IPROC_MSI_EQ_EN_SHIFT) | |
30 | ||
31 | #define IPROC_MSI_EQ_MASK 0x3f | |
32 | ||
33 | /* Max number of GIC interrupts */ | |
34 | #define NR_HW_IRQS 6 | |
35 | ||
36 | /* Number of entries in each event queue */ | |
37 | #define EQ_LEN 64 | |
38 | ||
39 | /* Size of each event queue memory region */ | |
40 | #define EQ_MEM_REGION_SIZE SZ_4K | |
41 | ||
42 | /* Size of each MSI address region */ | |
43 | #define MSI_MEM_REGION_SIZE SZ_4K | |
44 | ||
45 | enum iproc_msi_reg { | |
46 | IPROC_MSI_EQ_PAGE = 0, | |
47 | IPROC_MSI_EQ_PAGE_UPPER, | |
48 | IPROC_MSI_PAGE, | |
49 | IPROC_MSI_PAGE_UPPER, | |
50 | IPROC_MSI_CTRL, | |
51 | IPROC_MSI_EQ_HEAD, | |
52 | IPROC_MSI_EQ_TAIL, | |
53 | IPROC_MSI_INTS_EN, | |
54 | IPROC_MSI_REG_SIZE, | |
55 | }; | |
56 | ||
57 | struct iproc_msi; | |
58 | ||
59 | /** | |
60 | * iProc MSI group | |
61 | * | |
62 | * One MSI group is allocated per GIC interrupt, serviced by one iProc MSI | |
63 | * event queue. | |
64 | * | |
65 | * @msi: pointer to iProc MSI data | |
66 | * @gic_irq: GIC interrupt | |
67 | * @eq: Event queue number | |
68 | */ | |
69 | struct iproc_msi_grp { | |
70 | struct iproc_msi *msi; | |
71 | int gic_irq; | |
72 | unsigned int eq; | |
73 | }; | |
74 | ||
75 | /** | |
76 | * iProc event queue based MSI | |
77 | * | |
78 | * Only meant to be used on platforms without MSI support integrated into the | |
79 | * GIC. | |
80 | * | |
81 | * @pcie: pointer to iProc PCIe data | |
82 | * @reg_offsets: MSI register offsets | |
83 | * @grps: MSI groups | |
84 | * @nr_irqs: number of total interrupts connected to GIC | |
85 | * @nr_cpus: number of toal CPUs | |
86 | * @has_inten_reg: indicates the MSI interrupt enable register needs to be | |
87 | * set explicitly (required for some legacy platforms) | |
88 | * @bitmap: MSI vector bitmap | |
89 | * @bitmap_lock: lock to protect access to the MSI bitmap | |
90 | * @nr_msi_vecs: total number of MSI vectors | |
91 | * @inner_domain: inner IRQ domain | |
92 | * @msi_domain: MSI IRQ domain | |
93 | * @nr_eq_region: required number of 4K aligned memory region for MSI event | |
94 | * queues | |
95 | * @nr_msi_region: required number of 4K aligned address region for MSI posted | |
96 | * writes | |
97 | * @eq_cpu: pointer to allocated memory region for MSI event queues | |
98 | * @eq_dma: DMA address of MSI event queues | |
99 | * @msi_addr: MSI address | |
100 | */ | |
101 | struct iproc_msi { | |
102 | struct iproc_pcie *pcie; | |
103 | const u16 (*reg_offsets)[IPROC_MSI_REG_SIZE]; | |
104 | struct iproc_msi_grp *grps; | |
105 | int nr_irqs; | |
106 | int nr_cpus; | |
107 | bool has_inten_reg; | |
108 | unsigned long *bitmap; | |
109 | struct mutex bitmap_lock; | |
110 | unsigned int nr_msi_vecs; | |
111 | struct irq_domain *inner_domain; | |
112 | struct irq_domain *msi_domain; | |
113 | unsigned int nr_eq_region; | |
114 | unsigned int nr_msi_region; | |
115 | void *eq_cpu; | |
116 | dma_addr_t eq_dma; | |
117 | phys_addr_t msi_addr; | |
118 | }; | |
119 | ||
120 | static const u16 iproc_msi_reg_paxb[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = { | |
121 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x210, 0x250, 0x254, 0x208 }, | |
122 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x214, 0x258, 0x25c, 0x208 }, | |
123 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x218, 0x260, 0x264, 0x208 }, | |
124 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x21c, 0x268, 0x26c, 0x208 }, | |
125 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x220, 0x270, 0x274, 0x208 }, | |
126 | { 0x200, 0x2c0, 0x204, 0x2c4, 0x224, 0x278, 0x27c, 0x208 }, | |
127 | }; | |
128 | ||
129 | static const u16 iproc_msi_reg_paxc[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = { | |
130 | { 0xc00, 0xc04, 0xc08, 0xc0c, 0xc40, 0xc50, 0xc60 }, | |
131 | { 0xc10, 0xc14, 0xc18, 0xc1c, 0xc44, 0xc54, 0xc64 }, | |
132 | { 0xc20, 0xc24, 0xc28, 0xc2c, 0xc48, 0xc58, 0xc68 }, | |
133 | { 0xc30, 0xc34, 0xc38, 0xc3c, 0xc4c, 0xc5c, 0xc6c }, | |
134 | }; | |
135 | ||
136 | static inline u32 iproc_msi_read_reg(struct iproc_msi *msi, | |
137 | enum iproc_msi_reg reg, | |
138 | unsigned int eq) | |
139 | { | |
140 | struct iproc_pcie *pcie = msi->pcie; | |
141 | ||
142 | return readl_relaxed(pcie->base + msi->reg_offsets[eq][reg]); | |
143 | } | |
144 | ||
145 | static inline void iproc_msi_write_reg(struct iproc_msi *msi, | |
146 | enum iproc_msi_reg reg, | |
147 | int eq, u32 val) | |
148 | { | |
149 | struct iproc_pcie *pcie = msi->pcie; | |
150 | ||
151 | writel_relaxed(val, pcie->base + msi->reg_offsets[eq][reg]); | |
152 | } | |
153 | ||
154 | static inline u32 hwirq_to_group(struct iproc_msi *msi, unsigned long hwirq) | |
155 | { | |
156 | return (hwirq % msi->nr_irqs); | |
157 | } | |
158 | ||
159 | static inline unsigned int iproc_msi_addr_offset(struct iproc_msi *msi, | |
160 | unsigned long hwirq) | |
161 | { | |
162 | if (msi->nr_msi_region > 1) | |
163 | return hwirq_to_group(msi, hwirq) * MSI_MEM_REGION_SIZE; | |
164 | else | |
165 | return hwirq_to_group(msi, hwirq) * sizeof(u32); | |
166 | } | |
167 | ||
168 | static inline unsigned int iproc_msi_eq_offset(struct iproc_msi *msi, u32 eq) | |
169 | { | |
170 | if (msi->nr_eq_region > 1) | |
171 | return eq * EQ_MEM_REGION_SIZE; | |
172 | else | |
173 | return eq * EQ_LEN * sizeof(u32); | |
174 | } | |
175 | ||
176 | static struct irq_chip iproc_msi_irq_chip = { | |
177 | .name = "iProc-MSI", | |
178 | }; | |
179 | ||
180 | static struct msi_domain_info iproc_msi_domain_info = { | |
181 | .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | | |
182 | MSI_FLAG_PCI_MSIX, | |
183 | .chip = &iproc_msi_irq_chip, | |
184 | }; | |
185 | ||
186 | /* | |
187 | * In iProc PCIe core, each MSI group is serviced by a GIC interrupt and a | |
188 | * dedicated event queue. Each MSI group can support up to 64 MSI vectors. | |
189 | * | |
190 | * The number of MSI groups varies between different iProc SoCs. The total | |
191 | * number of CPU cores also varies. To support MSI IRQ affinity, we | |
192 | * distribute GIC interrupts across all available CPUs. MSI vector is moved | |
193 | * from one GIC interrupt to another to steer to the target CPU. | |
194 | * | |
195 | * Assuming: | |
196 | * - the number of MSI groups is M | |
197 | * - the number of CPU cores is N | |
198 | * - M is always a multiple of N | |
199 | * | |
200 | * Total number of raw MSI vectors = M * 64 | |
201 | * Total number of supported MSI vectors = (M * 64) / N | |
202 | */ | |
203 | static inline int hwirq_to_cpu(struct iproc_msi *msi, unsigned long hwirq) | |
204 | { | |
205 | return (hwirq % msi->nr_cpus); | |
206 | } | |
207 | ||
208 | static inline unsigned long hwirq_to_canonical_hwirq(struct iproc_msi *msi, | |
209 | unsigned long hwirq) | |
210 | { | |
211 | return (hwirq - hwirq_to_cpu(msi, hwirq)); | |
212 | } | |
213 | ||
214 | static int iproc_msi_irq_set_affinity(struct irq_data *data, | |
215 | const struct cpumask *mask, bool force) | |
216 | { | |
217 | struct iproc_msi *msi = irq_data_get_irq_chip_data(data); | |
218 | int target_cpu = cpumask_first(mask); | |
219 | int curr_cpu; | |
220 | ||
221 | curr_cpu = hwirq_to_cpu(msi, data->hwirq); | |
222 | if (curr_cpu == target_cpu) | |
223 | return IRQ_SET_MASK_OK_DONE; | |
224 | ||
225 | /* steer MSI to the target CPU */ | |
226 | data->hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq) + target_cpu; | |
227 | ||
228 | return IRQ_SET_MASK_OK; | |
229 | } | |
230 | ||
231 | static void iproc_msi_irq_compose_msi_msg(struct irq_data *data, | |
232 | struct msi_msg *msg) | |
233 | { | |
234 | struct iproc_msi *msi = irq_data_get_irq_chip_data(data); | |
235 | dma_addr_t addr; | |
236 | ||
237 | addr = msi->msi_addr + iproc_msi_addr_offset(msi, data->hwirq); | |
238 | msg->address_lo = lower_32_bits(addr); | |
239 | msg->address_hi = upper_32_bits(addr); | |
240 | msg->data = data->hwirq; | |
241 | } | |
242 | ||
243 | static struct irq_chip iproc_msi_bottom_irq_chip = { | |
244 | .name = "MSI", | |
245 | .irq_set_affinity = iproc_msi_irq_set_affinity, | |
246 | .irq_compose_msi_msg = iproc_msi_irq_compose_msi_msg, | |
247 | }; | |
248 | ||
249 | static int iproc_msi_irq_domain_alloc(struct irq_domain *domain, | |
250 | unsigned int virq, unsigned int nr_irqs, | |
251 | void *args) | |
252 | { | |
253 | struct iproc_msi *msi = domain->host_data; | |
254 | int hwirq; | |
255 | ||
256 | mutex_lock(&msi->bitmap_lock); | |
257 | ||
258 | /* Allocate 'nr_cpus' number of MSI vectors each time */ | |
259 | hwirq = bitmap_find_next_zero_area(msi->bitmap, msi->nr_msi_vecs, 0, | |
260 | msi->nr_cpus, 0); | |
261 | if (hwirq < msi->nr_msi_vecs) { | |
262 | bitmap_set(msi->bitmap, hwirq, msi->nr_cpus); | |
263 | } else { | |
264 | mutex_unlock(&msi->bitmap_lock); | |
265 | return -ENOSPC; | |
266 | } | |
267 | ||
268 | mutex_unlock(&msi->bitmap_lock); | |
269 | ||
270 | irq_domain_set_info(domain, virq, hwirq, &iproc_msi_bottom_irq_chip, | |
271 | domain->host_data, handle_simple_irq, NULL, NULL); | |
272 | ||
273 | return 0; | |
274 | } | |
275 | ||
276 | static void iproc_msi_irq_domain_free(struct irq_domain *domain, | |
277 | unsigned int virq, unsigned int nr_irqs) | |
278 | { | |
279 | struct irq_data *data = irq_domain_get_irq_data(domain, virq); | |
280 | struct iproc_msi *msi = irq_data_get_irq_chip_data(data); | |
281 | unsigned int hwirq; | |
282 | ||
283 | mutex_lock(&msi->bitmap_lock); | |
284 | ||
285 | hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq); | |
286 | bitmap_clear(msi->bitmap, hwirq, msi->nr_cpus); | |
287 | ||
288 | mutex_unlock(&msi->bitmap_lock); | |
289 | ||
290 | irq_domain_free_irqs_parent(domain, virq, nr_irqs); | |
291 | } | |
292 | ||
293 | static const struct irq_domain_ops msi_domain_ops = { | |
294 | .alloc = iproc_msi_irq_domain_alloc, | |
295 | .free = iproc_msi_irq_domain_free, | |
296 | }; | |
297 | ||
298 | static inline u32 decode_msi_hwirq(struct iproc_msi *msi, u32 eq, u32 head) | |
299 | { | |
300 | u32 *msg, hwirq; | |
301 | unsigned int offs; | |
302 | ||
303 | offs = iproc_msi_eq_offset(msi, eq) + head * sizeof(u32); | |
304 | msg = (u32 *)(msi->eq_cpu + offs); | |
305 | hwirq = *msg & IPROC_MSI_EQ_MASK; | |
306 | ||
307 | /* | |
308 | * Since we have multiple hwirq mapped to a single MSI vector, | |
309 | * now we need to derive the hwirq at CPU0. It can then be used to | |
310 | * mapped back to virq. | |
311 | */ | |
312 | return hwirq_to_canonical_hwirq(msi, hwirq); | |
313 | } | |
314 | ||
315 | static void iproc_msi_handler(struct irq_desc *desc) | |
316 | { | |
317 | struct irq_chip *chip = irq_desc_get_chip(desc); | |
318 | struct iproc_msi_grp *grp; | |
319 | struct iproc_msi *msi; | |
320 | struct iproc_pcie *pcie; | |
321 | u32 eq, head, tail, nr_events; | |
322 | unsigned long hwirq; | |
323 | int virq; | |
324 | ||
325 | chained_irq_enter(chip, desc); | |
326 | ||
327 | grp = irq_desc_get_handler_data(desc); | |
328 | msi = grp->msi; | |
329 | pcie = msi->pcie; | |
330 | eq = grp->eq; | |
331 | ||
332 | /* | |
333 | * iProc MSI event queue is tracked by head and tail pointers. Head | |
334 | * pointer indicates the next entry (MSI data) to be consumed by SW in | |
335 | * the queue and needs to be updated by SW. iProc MSI core uses the | |
336 | * tail pointer as the next data insertion point. | |
337 | * | |
338 | * Entries between head and tail pointers contain valid MSI data. MSI | |
339 | * data is guaranteed to be in the event queue memory before the tail | |
340 | * pointer is updated by the iProc MSI core. | |
341 | */ | |
342 | head = iproc_msi_read_reg(msi, IPROC_MSI_EQ_HEAD, | |
343 | eq) & IPROC_MSI_EQ_MASK; | |
344 | do { | |
345 | tail = iproc_msi_read_reg(msi, IPROC_MSI_EQ_TAIL, | |
346 | eq) & IPROC_MSI_EQ_MASK; | |
347 | ||
348 | /* | |
349 | * Figure out total number of events (MSI data) to be | |
350 | * processed. | |
351 | */ | |
352 | nr_events = (tail < head) ? | |
353 | (EQ_LEN - (head - tail)) : (tail - head); | |
354 | if (!nr_events) | |
355 | break; | |
356 | ||
357 | /* process all outstanding events */ | |
358 | while (nr_events--) { | |
359 | hwirq = decode_msi_hwirq(msi, eq, head); | |
360 | virq = irq_find_mapping(msi->inner_domain, hwirq); | |
361 | generic_handle_irq(virq); | |
362 | ||
363 | head++; | |
364 | head %= EQ_LEN; | |
365 | } | |
366 | ||
367 | /* | |
368 | * Now all outstanding events have been processed. Update the | |
369 | * head pointer. | |
370 | */ | |
371 | iproc_msi_write_reg(msi, IPROC_MSI_EQ_HEAD, eq, head); | |
372 | ||
373 | /* | |
374 | * Now go read the tail pointer again to see if there are new | |
375 | * oustanding events that came in during the above window. | |
376 | */ | |
377 | } while (true); | |
378 | ||
379 | chained_irq_exit(chip, desc); | |
380 | } | |
381 | ||
382 | static void iproc_msi_enable(struct iproc_msi *msi) | |
383 | { | |
384 | int i, eq; | |
385 | u32 val; | |
386 | ||
387 | /* Program memory region for each event queue */ | |
388 | for (i = 0; i < msi->nr_eq_region; i++) { | |
389 | dma_addr_t addr = msi->eq_dma + (i * EQ_MEM_REGION_SIZE); | |
390 | ||
391 | iproc_msi_write_reg(msi, IPROC_MSI_EQ_PAGE, i, | |
392 | lower_32_bits(addr)); | |
393 | iproc_msi_write_reg(msi, IPROC_MSI_EQ_PAGE_UPPER, i, | |
394 | upper_32_bits(addr)); | |
395 | } | |
396 | ||
397 | /* Program address region for MSI posted writes */ | |
398 | for (i = 0; i < msi->nr_msi_region; i++) { | |
399 | phys_addr_t addr = msi->msi_addr + (i * MSI_MEM_REGION_SIZE); | |
400 | ||
401 | iproc_msi_write_reg(msi, IPROC_MSI_PAGE, i, | |
402 | lower_32_bits(addr)); | |
403 | iproc_msi_write_reg(msi, IPROC_MSI_PAGE_UPPER, i, | |
404 | upper_32_bits(addr)); | |
405 | } | |
406 | ||
407 | for (eq = 0; eq < msi->nr_irqs; eq++) { | |
408 | /* Enable MSI event queue */ | |
409 | val = IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT | | |
410 | IPROC_MSI_EQ_EN; | |
411 | iproc_msi_write_reg(msi, IPROC_MSI_CTRL, eq, val); | |
412 | ||
413 | /* | |
414 | * Some legacy platforms require the MSI interrupt enable | |
415 | * register to be set explicitly. | |
416 | */ | |
417 | if (msi->has_inten_reg) { | |
418 | val = iproc_msi_read_reg(msi, IPROC_MSI_INTS_EN, eq); | |
419 | val |= BIT(eq); | |
420 | iproc_msi_write_reg(msi, IPROC_MSI_INTS_EN, eq, val); | |
421 | } | |
422 | } | |
423 | } | |
424 | ||
425 | static void iproc_msi_disable(struct iproc_msi *msi) | |
426 | { | |
427 | u32 eq, val; | |
428 | ||
429 | for (eq = 0; eq < msi->nr_irqs; eq++) { | |
430 | if (msi->has_inten_reg) { | |
431 | val = iproc_msi_read_reg(msi, IPROC_MSI_INTS_EN, eq); | |
432 | val &= ~BIT(eq); | |
433 | iproc_msi_write_reg(msi, IPROC_MSI_INTS_EN, eq, val); | |
434 | } | |
435 | ||
436 | val = iproc_msi_read_reg(msi, IPROC_MSI_CTRL, eq); | |
437 | val &= ~(IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT | | |
438 | IPROC_MSI_EQ_EN); | |
439 | iproc_msi_write_reg(msi, IPROC_MSI_CTRL, eq, val); | |
440 | } | |
441 | } | |
442 | ||
443 | static int iproc_msi_alloc_domains(struct device_node *node, | |
444 | struct iproc_msi *msi) | |
445 | { | |
446 | msi->inner_domain = irq_domain_add_linear(NULL, msi->nr_msi_vecs, | |
447 | &msi_domain_ops, msi); | |
448 | if (!msi->inner_domain) | |
449 | return -ENOMEM; | |
450 | ||
451 | msi->msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node), | |
452 | &iproc_msi_domain_info, | |
453 | msi->inner_domain); | |
454 | if (!msi->msi_domain) { | |
455 | irq_domain_remove(msi->inner_domain); | |
456 | return -ENOMEM; | |
457 | } | |
458 | ||
459 | return 0; | |
460 | } | |
461 | ||
462 | static void iproc_msi_free_domains(struct iproc_msi *msi) | |
463 | { | |
464 | if (msi->msi_domain) | |
465 | irq_domain_remove(msi->msi_domain); | |
466 | ||
467 | if (msi->inner_domain) | |
468 | irq_domain_remove(msi->inner_domain); | |
469 | } | |
470 | ||
471 | static void iproc_msi_irq_free(struct iproc_msi *msi, unsigned int cpu) | |
472 | { | |
473 | int i; | |
474 | ||
475 | for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) { | |
476 | irq_set_chained_handler_and_data(msi->grps[i].gic_irq, | |
477 | NULL, NULL); | |
478 | } | |
479 | } | |
480 | ||
481 | static int iproc_msi_irq_setup(struct iproc_msi *msi, unsigned int cpu) | |
482 | { | |
483 | int i, ret; | |
484 | cpumask_var_t mask; | |
485 | struct iproc_pcie *pcie = msi->pcie; | |
486 | ||
487 | for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) { | |
488 | irq_set_chained_handler_and_data(msi->grps[i].gic_irq, | |
489 | iproc_msi_handler, | |
490 | &msi->grps[i]); | |
491 | /* Dedicate GIC interrupt to each CPU core */ | |
492 | if (alloc_cpumask_var(&mask, GFP_KERNEL)) { | |
493 | cpumask_clear(mask); | |
494 | cpumask_set_cpu(cpu, mask); | |
495 | ret = irq_set_affinity(msi->grps[i].gic_irq, mask); | |
496 | if (ret) | |
497 | dev_err(pcie->dev, | |
498 | "failed to set affinity for IRQ%d\n", | |
499 | msi->grps[i].gic_irq); | |
500 | free_cpumask_var(mask); | |
501 | } else { | |
502 | dev_err(pcie->dev, "failed to alloc CPU mask\n"); | |
503 | ret = -EINVAL; | |
504 | } | |
505 | ||
506 | if (ret) { | |
507 | /* Free all configured/unconfigured IRQs */ | |
508 | iproc_msi_irq_free(msi, cpu); | |
509 | return ret; | |
510 | } | |
511 | } | |
512 | ||
513 | return 0; | |
514 | } | |
515 | ||
516 | int iproc_msi_init(struct iproc_pcie *pcie, struct device_node *node) | |
517 | { | |
518 | struct iproc_msi *msi; | |
519 | int i, ret; | |
520 | unsigned int cpu; | |
521 | ||
522 | if (!of_device_is_compatible(node, "brcm,iproc-msi")) | |
523 | return -ENODEV; | |
524 | ||
525 | if (!of_find_property(node, "msi-controller", NULL)) | |
526 | return -ENODEV; | |
527 | ||
528 | if (pcie->msi) | |
529 | return -EBUSY; | |
530 | ||
531 | msi = devm_kzalloc(pcie->dev, sizeof(*msi), GFP_KERNEL); | |
532 | if (!msi) | |
533 | return -ENOMEM; | |
534 | ||
535 | msi->pcie = pcie; | |
536 | pcie->msi = msi; | |
537 | msi->msi_addr = pcie->base_addr; | |
538 | mutex_init(&msi->bitmap_lock); | |
539 | msi->nr_cpus = num_possible_cpus(); | |
540 | ||
541 | msi->nr_irqs = of_irq_count(node); | |
542 | if (!msi->nr_irqs) { | |
543 | dev_err(pcie->dev, "found no MSI GIC interrupt\n"); | |
544 | return -ENODEV; | |
545 | } | |
546 | ||
547 | if (msi->nr_irqs > NR_HW_IRQS) { | |
548 | dev_warn(pcie->dev, "too many MSI GIC interrupts defined %d\n", | |
549 | msi->nr_irqs); | |
550 | msi->nr_irqs = NR_HW_IRQS; | |
551 | } | |
552 | ||
553 | if (msi->nr_irqs < msi->nr_cpus) { | |
554 | dev_err(pcie->dev, | |
555 | "not enough GIC interrupts for MSI affinity\n"); | |
556 | return -EINVAL; | |
557 | } | |
558 | ||
559 | if (msi->nr_irqs % msi->nr_cpus != 0) { | |
560 | msi->nr_irqs -= msi->nr_irqs % msi->nr_cpus; | |
561 | dev_warn(pcie->dev, "Reducing number of interrupts to %d\n", | |
562 | msi->nr_irqs); | |
563 | } | |
564 | ||
565 | switch (pcie->type) { | |
566 | case IPROC_PCIE_PAXB: | |
567 | msi->reg_offsets = iproc_msi_reg_paxb; | |
568 | msi->nr_eq_region = 1; | |
569 | msi->nr_msi_region = 1; | |
570 | break; | |
571 | case IPROC_PCIE_PAXC: | |
572 | msi->reg_offsets = iproc_msi_reg_paxc; | |
573 | msi->nr_eq_region = msi->nr_irqs; | |
574 | msi->nr_msi_region = msi->nr_irqs; | |
575 | break; | |
576 | default: | |
577 | dev_err(pcie->dev, "incompatible iProc PCIe interface\n"); | |
578 | return -EINVAL; | |
579 | } | |
580 | ||
581 | if (of_find_property(node, "brcm,pcie-msi-inten", NULL)) | |
582 | msi->has_inten_reg = true; | |
583 | ||
584 | msi->nr_msi_vecs = msi->nr_irqs * EQ_LEN; | |
585 | msi->bitmap = devm_kcalloc(pcie->dev, BITS_TO_LONGS(msi->nr_msi_vecs), | |
586 | sizeof(*msi->bitmap), GFP_KERNEL); | |
587 | if (!msi->bitmap) | |
588 | return -ENOMEM; | |
589 | ||
590 | msi->grps = devm_kcalloc(pcie->dev, msi->nr_irqs, sizeof(*msi->grps), | |
591 | GFP_KERNEL); | |
592 | if (!msi->grps) | |
593 | return -ENOMEM; | |
594 | ||
595 | for (i = 0; i < msi->nr_irqs; i++) { | |
596 | unsigned int irq = irq_of_parse_and_map(node, i); | |
597 | ||
598 | if (!irq) { | |
599 | dev_err(pcie->dev, "unable to parse/map interrupt\n"); | |
600 | ret = -ENODEV; | |
601 | goto free_irqs; | |
602 | } | |
603 | msi->grps[i].gic_irq = irq; | |
604 | msi->grps[i].msi = msi; | |
605 | msi->grps[i].eq = i; | |
606 | } | |
607 | ||
608 | /* Reserve memory for event queue and make sure memories are zeroed */ | |
609 | msi->eq_cpu = dma_zalloc_coherent(pcie->dev, | |
610 | msi->nr_eq_region * EQ_MEM_REGION_SIZE, | |
611 | &msi->eq_dma, GFP_KERNEL); | |
612 | if (!msi->eq_cpu) { | |
613 | ret = -ENOMEM; | |
614 | goto free_irqs; | |
615 | } | |
616 | ||
617 | ret = iproc_msi_alloc_domains(node, msi); | |
618 | if (ret) { | |
619 | dev_err(pcie->dev, "failed to create MSI domains\n"); | |
620 | goto free_eq_dma; | |
621 | } | |
622 | ||
623 | for_each_online_cpu(cpu) { | |
624 | ret = iproc_msi_irq_setup(msi, cpu); | |
625 | if (ret) | |
626 | goto free_msi_irq; | |
627 | } | |
628 | ||
629 | iproc_msi_enable(msi); | |
630 | ||
631 | return 0; | |
632 | ||
633 | free_msi_irq: | |
634 | for_each_online_cpu(cpu) | |
635 | iproc_msi_irq_free(msi, cpu); | |
636 | iproc_msi_free_domains(msi); | |
637 | ||
638 | free_eq_dma: | |
639 | dma_free_coherent(pcie->dev, msi->nr_eq_region * EQ_MEM_REGION_SIZE, | |
640 | msi->eq_cpu, msi->eq_dma); | |
641 | ||
642 | free_irqs: | |
643 | for (i = 0; i < msi->nr_irqs; i++) { | |
644 | if (msi->grps[i].gic_irq) | |
645 | irq_dispose_mapping(msi->grps[i].gic_irq); | |
646 | } | |
647 | pcie->msi = NULL; | |
648 | return ret; | |
649 | } | |
650 | EXPORT_SYMBOL(iproc_msi_init); | |
651 | ||
652 | void iproc_msi_exit(struct iproc_pcie *pcie) | |
653 | { | |
654 | struct iproc_msi *msi = pcie->msi; | |
655 | unsigned int i, cpu; | |
656 | ||
657 | if (!msi) | |
658 | return; | |
659 | ||
660 | iproc_msi_disable(msi); | |
661 | ||
662 | for_each_online_cpu(cpu) | |
663 | iproc_msi_irq_free(msi, cpu); | |
664 | ||
665 | iproc_msi_free_domains(msi); | |
666 | ||
667 | dma_free_coherent(pcie->dev, msi->nr_eq_region * EQ_MEM_REGION_SIZE, | |
668 | msi->eq_cpu, msi->eq_dma); | |
669 | ||
670 | for (i = 0; i < msi->nr_irqs; i++) { | |
671 | if (msi->grps[i].gic_irq) | |
672 | irq_dispose_mapping(msi->grps[i].gic_irq); | |
673 | } | |
674 | } | |
675 | EXPORT_SYMBOL(iproc_msi_exit); |