i3c: master: dw-i3c-master: mark expected switch fall-through
[linux-2.6-microblaze.git] / drivers / mailbox / bcm-flexrm-mailbox.c
1 /*
2  * Copyright (C) 2017 Broadcom
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 /*
15  * Broadcom FlexRM Mailbox Driver
16  *
17  * Each Broadcom FlexSparx4 offload engine is implemented as an
18  * extension to Broadcom FlexRM ring manager. The FlexRM ring
19  * manager provides a set of rings which can be used to submit
20  * work to a FlexSparx4 offload engine.
21  *
22  * This driver creates a mailbox controller using a set of FlexRM
23  * rings where each mailbox channel represents a separate FlexRM ring.
24  */
25
26 #include <asm/barrier.h>
27 #include <asm/byteorder.h>
28 #include <linux/atomic.h>
29 #include <linux/bitmap.h>
30 #include <linux/debugfs.h>
31 #include <linux/delay.h>
32 #include <linux/device.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/dmapool.h>
35 #include <linux/err.h>
36 #include <linux/interrupt.h>
37 #include <linux/kernel.h>
38 #include <linux/mailbox_controller.h>
39 #include <linux/mailbox_client.h>
40 #include <linux/mailbox/brcm-message.h>
41 #include <linux/module.h>
42 #include <linux/msi.h>
43 #include <linux/of_address.h>
44 #include <linux/of_irq.h>
45 #include <linux/platform_device.h>
46 #include <linux/spinlock.h>
47
48 /* ====== FlexRM register defines ===== */
49
50 /* FlexRM configuration */
51 #define RING_REGS_SIZE                                  0x10000
52 #define RING_DESC_SIZE                                  8
53 #define RING_DESC_INDEX(offset)                         \
54                         ((offset) / RING_DESC_SIZE)
55 #define RING_DESC_OFFSET(index)                         \
56                         ((index) * RING_DESC_SIZE)
57 #define RING_MAX_REQ_COUNT                              1024
58 #define RING_BD_ALIGN_ORDER                             12
59 #define RING_BD_ALIGN_CHECK(addr)                       \
60                         (!((addr) & ((0x1 << RING_BD_ALIGN_ORDER) - 1)))
61 #define RING_BD_TOGGLE_INVALID(offset)                  \
62                         (((offset) >> RING_BD_ALIGN_ORDER) & 0x1)
63 #define RING_BD_TOGGLE_VALID(offset)                    \
64                         (!RING_BD_TOGGLE_INVALID(offset))
65 #define RING_BD_DESC_PER_REQ                            32
66 #define RING_BD_DESC_COUNT                              \
67                         (RING_MAX_REQ_COUNT * RING_BD_DESC_PER_REQ)
68 #define RING_BD_SIZE                                    \
69                         (RING_BD_DESC_COUNT * RING_DESC_SIZE)
70 #define RING_CMPL_ALIGN_ORDER                           13
71 #define RING_CMPL_DESC_COUNT                            RING_MAX_REQ_COUNT
72 #define RING_CMPL_SIZE                                  \
73                         (RING_CMPL_DESC_COUNT * RING_DESC_SIZE)
74 #define RING_VER_MAGIC                                  0x76303031
75
76 /* Per-Ring register offsets */
77 #define RING_VER                                        0x000
78 #define RING_BD_START_ADDR                              0x004
79 #define RING_BD_READ_PTR                                0x008
80 #define RING_BD_WRITE_PTR                               0x00c
81 #define RING_BD_READ_PTR_DDR_LS                         0x010
82 #define RING_BD_READ_PTR_DDR_MS                         0x014
83 #define RING_CMPL_START_ADDR                            0x018
84 #define RING_CMPL_WRITE_PTR                             0x01c
85 #define RING_NUM_REQ_RECV_LS                            0x020
86 #define RING_NUM_REQ_RECV_MS                            0x024
87 #define RING_NUM_REQ_TRANS_LS                           0x028
88 #define RING_NUM_REQ_TRANS_MS                           0x02c
89 #define RING_NUM_REQ_OUTSTAND                           0x030
90 #define RING_CONTROL                                    0x034
91 #define RING_FLUSH_DONE                                 0x038
92 #define RING_MSI_ADDR_LS                                0x03c
93 #define RING_MSI_ADDR_MS                                0x040
94 #define RING_MSI_CONTROL                                0x048
95 #define RING_BD_READ_PTR_DDR_CONTROL                    0x04c
96 #define RING_MSI_DATA_VALUE                             0x064
97
98 /* Register RING_BD_START_ADDR fields */
99 #define BD_LAST_UPDATE_HW_SHIFT                         28
100 #define BD_LAST_UPDATE_HW_MASK                          0x1
101 #define BD_START_ADDR_VALUE(pa)                         \
102         ((u32)((((dma_addr_t)(pa)) >> RING_BD_ALIGN_ORDER) & 0x0fffffff))
103 #define BD_START_ADDR_DECODE(val)                       \
104         ((dma_addr_t)((val) & 0x0fffffff) << RING_BD_ALIGN_ORDER)
105
106 /* Register RING_CMPL_START_ADDR fields */
107 #define CMPL_START_ADDR_VALUE(pa)                       \
108         ((u32)((((u64)(pa)) >> RING_CMPL_ALIGN_ORDER) & 0x07ffffff))
109
110 /* Register RING_CONTROL fields */
111 #define CONTROL_MASK_DISABLE_CONTROL                    12
112 #define CONTROL_FLUSH_SHIFT                             5
113 #define CONTROL_ACTIVE_SHIFT                            4
114 #define CONTROL_RATE_ADAPT_MASK                         0xf
115 #define CONTROL_RATE_DYNAMIC                            0x0
116 #define CONTROL_RATE_FAST                               0x8
117 #define CONTROL_RATE_MEDIUM                             0x9
118 #define CONTROL_RATE_SLOW                               0xa
119 #define CONTROL_RATE_IDLE                               0xb
120
121 /* Register RING_FLUSH_DONE fields */
122 #define FLUSH_DONE_MASK                                 0x1
123
124 /* Register RING_MSI_CONTROL fields */
125 #define MSI_TIMER_VAL_SHIFT                             16
126 #define MSI_TIMER_VAL_MASK                              0xffff
127 #define MSI_ENABLE_SHIFT                                15
128 #define MSI_ENABLE_MASK                                 0x1
129 #define MSI_COUNT_SHIFT                                 0
130 #define MSI_COUNT_MASK                                  0x3ff
131
132 /* Register RING_BD_READ_PTR_DDR_CONTROL fields */
133 #define BD_READ_PTR_DDR_TIMER_VAL_SHIFT                 16
134 #define BD_READ_PTR_DDR_TIMER_VAL_MASK                  0xffff
135 #define BD_READ_PTR_DDR_ENABLE_SHIFT                    15
136 #define BD_READ_PTR_DDR_ENABLE_MASK                     0x1
137
138 /* ====== FlexRM ring descriptor defines ===== */
139
140 /* Completion descriptor format */
141 #define CMPL_OPAQUE_SHIFT                       0
142 #define CMPL_OPAQUE_MASK                        0xffff
143 #define CMPL_ENGINE_STATUS_SHIFT                16
144 #define CMPL_ENGINE_STATUS_MASK                 0xffff
145 #define CMPL_DME_STATUS_SHIFT                   32
146 #define CMPL_DME_STATUS_MASK                    0xffff
147 #define CMPL_RM_STATUS_SHIFT                    48
148 #define CMPL_RM_STATUS_MASK                     0xffff
149
150 /* Completion DME status code */
151 #define DME_STATUS_MEM_COR_ERR                  BIT(0)
152 #define DME_STATUS_MEM_UCOR_ERR                 BIT(1)
153 #define DME_STATUS_FIFO_UNDERFLOW               BIT(2)
154 #define DME_STATUS_FIFO_OVERFLOW                BIT(3)
155 #define DME_STATUS_RRESP_ERR                    BIT(4)
156 #define DME_STATUS_BRESP_ERR                    BIT(5)
157 #define DME_STATUS_ERROR_MASK                   (DME_STATUS_MEM_COR_ERR | \
158                                                  DME_STATUS_MEM_UCOR_ERR | \
159                                                  DME_STATUS_FIFO_UNDERFLOW | \
160                                                  DME_STATUS_FIFO_OVERFLOW | \
161                                                  DME_STATUS_RRESP_ERR | \
162                                                  DME_STATUS_BRESP_ERR)
163
164 /* Completion RM status code */
165 #define RM_STATUS_CODE_SHIFT                    0
166 #define RM_STATUS_CODE_MASK                     0x3ff
167 #define RM_STATUS_CODE_GOOD                     0x0
168 #define RM_STATUS_CODE_AE_TIMEOUT               0x3ff
169
170 /* General descriptor format */
171 #define DESC_TYPE_SHIFT                         60
172 #define DESC_TYPE_MASK                          0xf
173 #define DESC_PAYLOAD_SHIFT                      0
174 #define DESC_PAYLOAD_MASK                       0x0fffffffffffffff
175
176 /* Null descriptor format  */
177 #define NULL_TYPE                               0
178 #define NULL_TOGGLE_SHIFT                       58
179 #define NULL_TOGGLE_MASK                        0x1
180
181 /* Header descriptor format */
182 #define HEADER_TYPE                             1
183 #define HEADER_TOGGLE_SHIFT                     58
184 #define HEADER_TOGGLE_MASK                      0x1
185 #define HEADER_ENDPKT_SHIFT                     57
186 #define HEADER_ENDPKT_MASK                      0x1
187 #define HEADER_STARTPKT_SHIFT                   56
188 #define HEADER_STARTPKT_MASK                    0x1
189 #define HEADER_BDCOUNT_SHIFT                    36
190 #define HEADER_BDCOUNT_MASK                     0x1f
191 #define HEADER_BDCOUNT_MAX                      HEADER_BDCOUNT_MASK
192 #define HEADER_FLAGS_SHIFT                      16
193 #define HEADER_FLAGS_MASK                       0xffff
194 #define HEADER_OPAQUE_SHIFT                     0
195 #define HEADER_OPAQUE_MASK                      0xffff
196
197 /* Source (SRC) descriptor format */
198 #define SRC_TYPE                                2
199 #define SRC_LENGTH_SHIFT                        44
200 #define SRC_LENGTH_MASK                         0xffff
201 #define SRC_ADDR_SHIFT                          0
202 #define SRC_ADDR_MASK                           0x00000fffffffffff
203
204 /* Destination (DST) descriptor format */
205 #define DST_TYPE                                3
206 #define DST_LENGTH_SHIFT                        44
207 #define DST_LENGTH_MASK                         0xffff
208 #define DST_ADDR_SHIFT                          0
209 #define DST_ADDR_MASK                           0x00000fffffffffff
210
211 /* Immediate (IMM) descriptor format */
212 #define IMM_TYPE                                4
213 #define IMM_DATA_SHIFT                          0
214 #define IMM_DATA_MASK                           0x0fffffffffffffff
215
216 /* Next pointer (NPTR) descriptor format */
217 #define NPTR_TYPE                               5
218 #define NPTR_TOGGLE_SHIFT                       58
219 #define NPTR_TOGGLE_MASK                        0x1
220 #define NPTR_ADDR_SHIFT                         0
221 #define NPTR_ADDR_MASK                          0x00000fffffffffff
222
223 /* Mega source (MSRC) descriptor format */
224 #define MSRC_TYPE                               6
225 #define MSRC_LENGTH_SHIFT                       44
226 #define MSRC_LENGTH_MASK                        0xffff
227 #define MSRC_ADDR_SHIFT                         0
228 #define MSRC_ADDR_MASK                          0x00000fffffffffff
229
230 /* Mega destination (MDST) descriptor format */
231 #define MDST_TYPE                               7
232 #define MDST_LENGTH_SHIFT                       44
233 #define MDST_LENGTH_MASK                        0xffff
234 #define MDST_ADDR_SHIFT                         0
235 #define MDST_ADDR_MASK                          0x00000fffffffffff
236
237 /* Source with tlast (SRCT) descriptor format */
238 #define SRCT_TYPE                               8
239 #define SRCT_LENGTH_SHIFT                       44
240 #define SRCT_LENGTH_MASK                        0xffff
241 #define SRCT_ADDR_SHIFT                         0
242 #define SRCT_ADDR_MASK                          0x00000fffffffffff
243
244 /* Destination with tlast (DSTT) descriptor format */
245 #define DSTT_TYPE                               9
246 #define DSTT_LENGTH_SHIFT                       44
247 #define DSTT_LENGTH_MASK                        0xffff
248 #define DSTT_ADDR_SHIFT                         0
249 #define DSTT_ADDR_MASK                          0x00000fffffffffff
250
251 /* Immediate with tlast (IMMT) descriptor format */
252 #define IMMT_TYPE                               10
253 #define IMMT_DATA_SHIFT                         0
254 #define IMMT_DATA_MASK                          0x0fffffffffffffff
255
256 /* Descriptor helper macros */
257 #define DESC_DEC(_d, _s, _m)                    (((_d) >> (_s)) & (_m))
258 #define DESC_ENC(_d, _v, _s, _m)                \
259                         do { \
260                                 (_d) &= ~((u64)(_m) << (_s)); \
261                                 (_d) |= (((u64)(_v) & (_m)) << (_s)); \
262                         } while (0)
263
264 /* ====== FlexRM data structures ===== */
265
266 struct flexrm_ring {
267         /* Unprotected members */
268         int num;
269         struct flexrm_mbox *mbox;
270         void __iomem *regs;
271         bool irq_requested;
272         unsigned int irq;
273         cpumask_t irq_aff_hint;
274         unsigned int msi_timer_val;
275         unsigned int msi_count_threshold;
276         struct brcm_message *requests[RING_MAX_REQ_COUNT];
277         void *bd_base;
278         dma_addr_t bd_dma_base;
279         u32 bd_write_offset;
280         void *cmpl_base;
281         dma_addr_t cmpl_dma_base;
282         /* Atomic stats */
283         atomic_t msg_send_count;
284         atomic_t msg_cmpl_count;
285         /* Protected members */
286         spinlock_t lock;
287         DECLARE_BITMAP(requests_bmap, RING_MAX_REQ_COUNT);
288         u32 cmpl_read_offset;
289 };
290
291 struct flexrm_mbox {
292         struct device *dev;
293         void __iomem *regs;
294         u32 num_rings;
295         struct flexrm_ring *rings;
296         struct dma_pool *bd_pool;
297         struct dma_pool *cmpl_pool;
298         struct dentry *root;
299         struct dentry *config;
300         struct dentry *stats;
301         struct mbox_controller controller;
302 };
303
304 /* ====== FlexRM ring descriptor helper routines ===== */
305
306 static u64 flexrm_read_desc(void *desc_ptr)
307 {
308         return le64_to_cpu(*((u64 *)desc_ptr));
309 }
310
311 static void flexrm_write_desc(void *desc_ptr, u64 desc)
312 {
313         *((u64 *)desc_ptr) = cpu_to_le64(desc);
314 }
315
316 static u32 flexrm_cmpl_desc_to_reqid(u64 cmpl_desc)
317 {
318         return (u32)(cmpl_desc & CMPL_OPAQUE_MASK);
319 }
320
321 static int flexrm_cmpl_desc_to_error(u64 cmpl_desc)
322 {
323         u32 status;
324
325         status = DESC_DEC(cmpl_desc, CMPL_DME_STATUS_SHIFT,
326                           CMPL_DME_STATUS_MASK);
327         if (status & DME_STATUS_ERROR_MASK)
328                 return -EIO;
329
330         status = DESC_DEC(cmpl_desc, CMPL_RM_STATUS_SHIFT,
331                           CMPL_RM_STATUS_MASK);
332         status &= RM_STATUS_CODE_MASK;
333         if (status == RM_STATUS_CODE_AE_TIMEOUT)
334                 return -ETIMEDOUT;
335
336         return 0;
337 }
338
339 static bool flexrm_is_next_table_desc(void *desc_ptr)
340 {
341         u64 desc = flexrm_read_desc(desc_ptr);
342         u32 type = DESC_DEC(desc, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
343
344         return (type == NPTR_TYPE) ? true : false;
345 }
346
347 static u64 flexrm_next_table_desc(u32 toggle, dma_addr_t next_addr)
348 {
349         u64 desc = 0;
350
351         DESC_ENC(desc, NPTR_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
352         DESC_ENC(desc, toggle, NPTR_TOGGLE_SHIFT, NPTR_TOGGLE_MASK);
353         DESC_ENC(desc, next_addr, NPTR_ADDR_SHIFT, NPTR_ADDR_MASK);
354
355         return desc;
356 }
357
358 static u64 flexrm_null_desc(u32 toggle)
359 {
360         u64 desc = 0;
361
362         DESC_ENC(desc, NULL_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
363         DESC_ENC(desc, toggle, NULL_TOGGLE_SHIFT, NULL_TOGGLE_MASK);
364
365         return desc;
366 }
367
368 static u32 flexrm_estimate_header_desc_count(u32 nhcnt)
369 {
370         u32 hcnt = nhcnt / HEADER_BDCOUNT_MAX;
371
372         if (!(nhcnt % HEADER_BDCOUNT_MAX))
373                 hcnt += 1;
374
375         return hcnt;
376 }
377
378 static void flexrm_flip_header_toggle(void *desc_ptr)
379 {
380         u64 desc = flexrm_read_desc(desc_ptr);
381
382         if (desc & ((u64)0x1 << HEADER_TOGGLE_SHIFT))
383                 desc &= ~((u64)0x1 << HEADER_TOGGLE_SHIFT);
384         else
385                 desc |= ((u64)0x1 << HEADER_TOGGLE_SHIFT);
386
387         flexrm_write_desc(desc_ptr, desc);
388 }
389
390 static u64 flexrm_header_desc(u32 toggle, u32 startpkt, u32 endpkt,
391                                u32 bdcount, u32 flags, u32 opaque)
392 {
393         u64 desc = 0;
394
395         DESC_ENC(desc, HEADER_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
396         DESC_ENC(desc, toggle, HEADER_TOGGLE_SHIFT, HEADER_TOGGLE_MASK);
397         DESC_ENC(desc, startpkt, HEADER_STARTPKT_SHIFT, HEADER_STARTPKT_MASK);
398         DESC_ENC(desc, endpkt, HEADER_ENDPKT_SHIFT, HEADER_ENDPKT_MASK);
399         DESC_ENC(desc, bdcount, HEADER_BDCOUNT_SHIFT, HEADER_BDCOUNT_MASK);
400         DESC_ENC(desc, flags, HEADER_FLAGS_SHIFT, HEADER_FLAGS_MASK);
401         DESC_ENC(desc, opaque, HEADER_OPAQUE_SHIFT, HEADER_OPAQUE_MASK);
402
403         return desc;
404 }
405
406 static void flexrm_enqueue_desc(u32 nhpos, u32 nhcnt, u32 reqid,
407                                  u64 desc, void **desc_ptr, u32 *toggle,
408                                  void *start_desc, void *end_desc)
409 {
410         u64 d;
411         u32 nhavail, _toggle, _startpkt, _endpkt, _bdcount;
412
413         /* Sanity check */
414         if (nhcnt <= nhpos)
415                 return;
416
417         /*
418          * Each request or packet start with a HEADER descriptor followed
419          * by one or more non-HEADER descriptors (SRC, SRCT, MSRC, DST,
420          * DSTT, MDST, IMM, and IMMT). The number of non-HEADER descriptors
421          * following a HEADER descriptor is represented by BDCOUNT field
422          * of HEADER descriptor. The max value of BDCOUNT field is 31 which
423          * means we can only have 31 non-HEADER descriptors following one
424          * HEADER descriptor.
425          *
426          * In general use, number of non-HEADER descriptors can easily go
427          * beyond 31. To tackle this situation, we have packet (or request)
428          * extenstion bits (STARTPKT and ENDPKT) in the HEADER descriptor.
429          *
430          * To use packet extension, the first HEADER descriptor of request
431          * (or packet) will have STARTPKT=1 and ENDPKT=0. The intermediate
432          * HEADER descriptors will have STARTPKT=0 and ENDPKT=0. The last
433          * HEADER descriptor will have STARTPKT=0 and ENDPKT=1. Also, the
434          * TOGGLE bit of the first HEADER will be set to invalid state to
435          * ensure that FlexRM does not start fetching descriptors till all
436          * descriptors are enqueued. The user of this function will flip
437          * the TOGGLE bit of first HEADER after all descriptors are
438          * enqueued.
439          */
440
441         if ((nhpos % HEADER_BDCOUNT_MAX == 0) && (nhcnt - nhpos)) {
442                 /* Prepare the header descriptor */
443                 nhavail = (nhcnt - nhpos);
444                 _toggle = (nhpos == 0) ? !(*toggle) : (*toggle);
445                 _startpkt = (nhpos == 0) ? 0x1 : 0x0;
446                 _endpkt = (nhavail <= HEADER_BDCOUNT_MAX) ? 0x1 : 0x0;
447                 _bdcount = (nhavail <= HEADER_BDCOUNT_MAX) ?
448                                 nhavail : HEADER_BDCOUNT_MAX;
449                 if (nhavail <= HEADER_BDCOUNT_MAX)
450                         _bdcount = nhavail;
451                 else
452                         _bdcount = HEADER_BDCOUNT_MAX;
453                 d = flexrm_header_desc(_toggle, _startpkt, _endpkt,
454                                         _bdcount, 0x0, reqid);
455
456                 /* Write header descriptor */
457                 flexrm_write_desc(*desc_ptr, d);
458
459                 /* Point to next descriptor */
460                 *desc_ptr += sizeof(desc);
461                 if (*desc_ptr == end_desc)
462                         *desc_ptr = start_desc;
463
464                 /* Skip next pointer descriptors */
465                 while (flexrm_is_next_table_desc(*desc_ptr)) {
466                         *toggle = (*toggle) ? 0 : 1;
467                         *desc_ptr += sizeof(desc);
468                         if (*desc_ptr == end_desc)
469                                 *desc_ptr = start_desc;
470                 }
471         }
472
473         /* Write desired descriptor */
474         flexrm_write_desc(*desc_ptr, desc);
475
476         /* Point to next descriptor */
477         *desc_ptr += sizeof(desc);
478         if (*desc_ptr == end_desc)
479                 *desc_ptr = start_desc;
480
481         /* Skip next pointer descriptors */
482         while (flexrm_is_next_table_desc(*desc_ptr)) {
483                 *toggle = (*toggle) ? 0 : 1;
484                 *desc_ptr += sizeof(desc);
485                 if (*desc_ptr == end_desc)
486                         *desc_ptr = start_desc;
487         }
488 }
489
490 static u64 flexrm_src_desc(dma_addr_t addr, unsigned int length)
491 {
492         u64 desc = 0;
493
494         DESC_ENC(desc, SRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
495         DESC_ENC(desc, length, SRC_LENGTH_SHIFT, SRC_LENGTH_MASK);
496         DESC_ENC(desc, addr, SRC_ADDR_SHIFT, SRC_ADDR_MASK);
497
498         return desc;
499 }
500
501 static u64 flexrm_msrc_desc(dma_addr_t addr, unsigned int length_div_16)
502 {
503         u64 desc = 0;
504
505         DESC_ENC(desc, MSRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
506         DESC_ENC(desc, length_div_16, MSRC_LENGTH_SHIFT, MSRC_LENGTH_MASK);
507         DESC_ENC(desc, addr, MSRC_ADDR_SHIFT, MSRC_ADDR_MASK);
508
509         return desc;
510 }
511
512 static u64 flexrm_dst_desc(dma_addr_t addr, unsigned int length)
513 {
514         u64 desc = 0;
515
516         DESC_ENC(desc, DST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
517         DESC_ENC(desc, length, DST_LENGTH_SHIFT, DST_LENGTH_MASK);
518         DESC_ENC(desc, addr, DST_ADDR_SHIFT, DST_ADDR_MASK);
519
520         return desc;
521 }
522
523 static u64 flexrm_mdst_desc(dma_addr_t addr, unsigned int length_div_16)
524 {
525         u64 desc = 0;
526
527         DESC_ENC(desc, MDST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
528         DESC_ENC(desc, length_div_16, MDST_LENGTH_SHIFT, MDST_LENGTH_MASK);
529         DESC_ENC(desc, addr, MDST_ADDR_SHIFT, MDST_ADDR_MASK);
530
531         return desc;
532 }
533
534 static u64 flexrm_imm_desc(u64 data)
535 {
536         u64 desc = 0;
537
538         DESC_ENC(desc, IMM_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
539         DESC_ENC(desc, data, IMM_DATA_SHIFT, IMM_DATA_MASK);
540
541         return desc;
542 }
543
544 static u64 flexrm_srct_desc(dma_addr_t addr, unsigned int length)
545 {
546         u64 desc = 0;
547
548         DESC_ENC(desc, SRCT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
549         DESC_ENC(desc, length, SRCT_LENGTH_SHIFT, SRCT_LENGTH_MASK);
550         DESC_ENC(desc, addr, SRCT_ADDR_SHIFT, SRCT_ADDR_MASK);
551
552         return desc;
553 }
554
555 static u64 flexrm_dstt_desc(dma_addr_t addr, unsigned int length)
556 {
557         u64 desc = 0;
558
559         DESC_ENC(desc, DSTT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
560         DESC_ENC(desc, length, DSTT_LENGTH_SHIFT, DSTT_LENGTH_MASK);
561         DESC_ENC(desc, addr, DSTT_ADDR_SHIFT, DSTT_ADDR_MASK);
562
563         return desc;
564 }
565
566 static u64 flexrm_immt_desc(u64 data)
567 {
568         u64 desc = 0;
569
570         DESC_ENC(desc, IMMT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
571         DESC_ENC(desc, data, IMMT_DATA_SHIFT, IMMT_DATA_MASK);
572
573         return desc;
574 }
575
576 static bool flexrm_spu_sanity_check(struct brcm_message *msg)
577 {
578         struct scatterlist *sg;
579
580         if (!msg->spu.src || !msg->spu.dst)
581                 return false;
582         for (sg = msg->spu.src; sg; sg = sg_next(sg)) {
583                 if (sg->length & 0xf) {
584                         if (sg->length > SRC_LENGTH_MASK)
585                                 return false;
586                 } else {
587                         if (sg->length > (MSRC_LENGTH_MASK * 16))
588                                 return false;
589                 }
590         }
591         for (sg = msg->spu.dst; sg; sg = sg_next(sg)) {
592                 if (sg->length & 0xf) {
593                         if (sg->length > DST_LENGTH_MASK)
594                                 return false;
595                 } else {
596                         if (sg->length > (MDST_LENGTH_MASK * 16))
597                                 return false;
598                 }
599         }
600
601         return true;
602 }
603
604 static u32 flexrm_spu_estimate_nonheader_desc_count(struct brcm_message *msg)
605 {
606         u32 cnt = 0;
607         unsigned int dst_target = 0;
608         struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
609
610         while (src_sg || dst_sg) {
611                 if (src_sg) {
612                         cnt++;
613                         dst_target = src_sg->length;
614                         src_sg = sg_next(src_sg);
615                 } else
616                         dst_target = UINT_MAX;
617
618                 while (dst_target && dst_sg) {
619                         cnt++;
620                         if (dst_sg->length < dst_target)
621                                 dst_target -= dst_sg->length;
622                         else
623                                 dst_target = 0;
624                         dst_sg = sg_next(dst_sg);
625                 }
626         }
627
628         return cnt;
629 }
630
631 static int flexrm_spu_dma_map(struct device *dev, struct brcm_message *msg)
632 {
633         int rc;
634
635         rc = dma_map_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
636                         DMA_TO_DEVICE);
637         if (rc < 0)
638                 return rc;
639
640         rc = dma_map_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
641                         DMA_FROM_DEVICE);
642         if (rc < 0) {
643                 dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
644                              DMA_TO_DEVICE);
645                 return rc;
646         }
647
648         return 0;
649 }
650
651 static void flexrm_spu_dma_unmap(struct device *dev, struct brcm_message *msg)
652 {
653         dma_unmap_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
654                      DMA_FROM_DEVICE);
655         dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
656                      DMA_TO_DEVICE);
657 }
658
659 static void *flexrm_spu_write_descs(struct brcm_message *msg, u32 nhcnt,
660                                      u32 reqid, void *desc_ptr, u32 toggle,
661                                      void *start_desc, void *end_desc)
662 {
663         u64 d;
664         u32 nhpos = 0;
665         void *orig_desc_ptr = desc_ptr;
666         unsigned int dst_target = 0;
667         struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
668
669         while (src_sg || dst_sg) {
670                 if (src_sg) {
671                         if (sg_dma_len(src_sg) & 0xf)
672                                 d = flexrm_src_desc(sg_dma_address(src_sg),
673                                                      sg_dma_len(src_sg));
674                         else
675                                 d = flexrm_msrc_desc(sg_dma_address(src_sg),
676                                                       sg_dma_len(src_sg)/16);
677                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
678                                              d, &desc_ptr, &toggle,
679                                              start_desc, end_desc);
680                         nhpos++;
681                         dst_target = sg_dma_len(src_sg);
682                         src_sg = sg_next(src_sg);
683                 } else
684                         dst_target = UINT_MAX;
685
686                 while (dst_target && dst_sg) {
687                         if (sg_dma_len(dst_sg) & 0xf)
688                                 d = flexrm_dst_desc(sg_dma_address(dst_sg),
689                                                      sg_dma_len(dst_sg));
690                         else
691                                 d = flexrm_mdst_desc(sg_dma_address(dst_sg),
692                                                       sg_dma_len(dst_sg)/16);
693                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
694                                              d, &desc_ptr, &toggle,
695                                              start_desc, end_desc);
696                         nhpos++;
697                         if (sg_dma_len(dst_sg) < dst_target)
698                                 dst_target -= sg_dma_len(dst_sg);
699                         else
700                                 dst_target = 0;
701                         dst_sg = sg_next(dst_sg);
702                 }
703         }
704
705         /* Null descriptor with invalid toggle bit */
706         flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
707
708         /* Ensure that descriptors have been written to memory */
709         wmb();
710
711         /* Flip toggle bit in header */
712         flexrm_flip_header_toggle(orig_desc_ptr);
713
714         return desc_ptr;
715 }
716
717 static bool flexrm_sba_sanity_check(struct brcm_message *msg)
718 {
719         u32 i;
720
721         if (!msg->sba.cmds || !msg->sba.cmds_count)
722                 return false;
723
724         for (i = 0; i < msg->sba.cmds_count; i++) {
725                 if (((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
726                      (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C)) &&
727                     (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT))
728                         return false;
729                 if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) &&
730                     (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
731                         return false;
732                 if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C) &&
733                     (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
734                         return false;
735                 if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP) &&
736                     (msg->sba.cmds[i].resp_len > DSTT_LENGTH_MASK))
737                         return false;
738                 if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT) &&
739                     (msg->sba.cmds[i].data_len > DSTT_LENGTH_MASK))
740                         return false;
741         }
742
743         return true;
744 }
745
746 static u32 flexrm_sba_estimate_nonheader_desc_count(struct brcm_message *msg)
747 {
748         u32 i, cnt;
749
750         cnt = 0;
751         for (i = 0; i < msg->sba.cmds_count; i++) {
752                 cnt++;
753
754                 if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
755                     (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C))
756                         cnt++;
757
758                 if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP)
759                         cnt++;
760
761                 if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT)
762                         cnt++;
763         }
764
765         return cnt;
766 }
767
768 static void *flexrm_sba_write_descs(struct brcm_message *msg, u32 nhcnt,
769                                      u32 reqid, void *desc_ptr, u32 toggle,
770                                      void *start_desc, void *end_desc)
771 {
772         u64 d;
773         u32 i, nhpos = 0;
774         struct brcm_sba_command *c;
775         void *orig_desc_ptr = desc_ptr;
776
777         /* Convert SBA commands into descriptors */
778         for (i = 0; i < msg->sba.cmds_count; i++) {
779                 c = &msg->sba.cmds[i];
780
781                 if ((c->flags & BRCM_SBA_CMD_HAS_RESP) &&
782                     (c->flags & BRCM_SBA_CMD_HAS_OUTPUT)) {
783                         /* Destination response descriptor */
784                         d = flexrm_dst_desc(c->resp, c->resp_len);
785                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
786                                              d, &desc_ptr, &toggle,
787                                              start_desc, end_desc);
788                         nhpos++;
789                 } else if (c->flags & BRCM_SBA_CMD_HAS_RESP) {
790                         /* Destination response with tlast descriptor */
791                         d = flexrm_dstt_desc(c->resp, c->resp_len);
792                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
793                                              d, &desc_ptr, &toggle,
794                                              start_desc, end_desc);
795                         nhpos++;
796                 }
797
798                 if (c->flags & BRCM_SBA_CMD_HAS_OUTPUT) {
799                         /* Destination with tlast descriptor */
800                         d = flexrm_dstt_desc(c->data, c->data_len);
801                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
802                                              d, &desc_ptr, &toggle,
803                                              start_desc, end_desc);
804                         nhpos++;
805                 }
806
807                 if (c->flags & BRCM_SBA_CMD_TYPE_B) {
808                         /* Command as immediate descriptor */
809                         d = flexrm_imm_desc(c->cmd);
810                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
811                                              d, &desc_ptr, &toggle,
812                                              start_desc, end_desc);
813                         nhpos++;
814                 } else {
815                         /* Command as immediate descriptor with tlast */
816                         d = flexrm_immt_desc(c->cmd);
817                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
818                                              d, &desc_ptr, &toggle,
819                                              start_desc, end_desc);
820                         nhpos++;
821                 }
822
823                 if ((c->flags & BRCM_SBA_CMD_TYPE_B) ||
824                     (c->flags & BRCM_SBA_CMD_TYPE_C)) {
825                         /* Source with tlast descriptor */
826                         d = flexrm_srct_desc(c->data, c->data_len);
827                         flexrm_enqueue_desc(nhpos, nhcnt, reqid,
828                                              d, &desc_ptr, &toggle,
829                                              start_desc, end_desc);
830                         nhpos++;
831                 }
832         }
833
834         /* Null descriptor with invalid toggle bit */
835         flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
836
837         /* Ensure that descriptors have been written to memory */
838         wmb();
839
840         /* Flip toggle bit in header */
841         flexrm_flip_header_toggle(orig_desc_ptr);
842
843         return desc_ptr;
844 }
845
846 static bool flexrm_sanity_check(struct brcm_message *msg)
847 {
848         if (!msg)
849                 return false;
850
851         switch (msg->type) {
852         case BRCM_MESSAGE_SPU:
853                 return flexrm_spu_sanity_check(msg);
854         case BRCM_MESSAGE_SBA:
855                 return flexrm_sba_sanity_check(msg);
856         default:
857                 return false;
858         };
859 }
860
861 static u32 flexrm_estimate_nonheader_desc_count(struct brcm_message *msg)
862 {
863         if (!msg)
864                 return 0;
865
866         switch (msg->type) {
867         case BRCM_MESSAGE_SPU:
868                 return flexrm_spu_estimate_nonheader_desc_count(msg);
869         case BRCM_MESSAGE_SBA:
870                 return flexrm_sba_estimate_nonheader_desc_count(msg);
871         default:
872                 return 0;
873         };
874 }
875
876 static int flexrm_dma_map(struct device *dev, struct brcm_message *msg)
877 {
878         if (!dev || !msg)
879                 return -EINVAL;
880
881         switch (msg->type) {
882         case BRCM_MESSAGE_SPU:
883                 return flexrm_spu_dma_map(dev, msg);
884         default:
885                 break;
886         }
887
888         return 0;
889 }
890
891 static void flexrm_dma_unmap(struct device *dev, struct brcm_message *msg)
892 {
893         if (!dev || !msg)
894                 return;
895
896         switch (msg->type) {
897         case BRCM_MESSAGE_SPU:
898                 flexrm_spu_dma_unmap(dev, msg);
899                 break;
900         default:
901                 break;
902         }
903 }
904
905 static void *flexrm_write_descs(struct brcm_message *msg, u32 nhcnt,
906                                 u32 reqid, void *desc_ptr, u32 toggle,
907                                 void *start_desc, void *end_desc)
908 {
909         if (!msg || !desc_ptr || !start_desc || !end_desc)
910                 return ERR_PTR(-ENOTSUPP);
911
912         if ((desc_ptr < start_desc) || (end_desc <= desc_ptr))
913                 return ERR_PTR(-ERANGE);
914
915         switch (msg->type) {
916         case BRCM_MESSAGE_SPU:
917                 return flexrm_spu_write_descs(msg, nhcnt, reqid,
918                                                desc_ptr, toggle,
919                                                start_desc, end_desc);
920         case BRCM_MESSAGE_SBA:
921                 return flexrm_sba_write_descs(msg, nhcnt, reqid,
922                                                desc_ptr, toggle,
923                                                start_desc, end_desc);
924         default:
925                 return ERR_PTR(-ENOTSUPP);
926         };
927 }
928
929 /* ====== FlexRM driver helper routines ===== */
930
931 static void flexrm_write_config_in_seqfile(struct flexrm_mbox *mbox,
932                                            struct seq_file *file)
933 {
934         int i;
935         const char *state;
936         struct flexrm_ring *ring;
937
938         seq_printf(file, "%-5s %-9s %-18s %-10s %-18s %-10s\n",
939                    "Ring#", "State", "BD_Addr", "BD_Size",
940                    "Cmpl_Addr", "Cmpl_Size");
941
942         for (i = 0; i < mbox->num_rings; i++) {
943                 ring = &mbox->rings[i];
944                 if (readl(ring->regs + RING_CONTROL) &
945                     BIT(CONTROL_ACTIVE_SHIFT))
946                         state = "active";
947                 else
948                         state = "inactive";
949                 seq_printf(file,
950                            "%-5d %-9s 0x%016llx 0x%08x 0x%016llx 0x%08x\n",
951                            ring->num, state,
952                            (unsigned long long)ring->bd_dma_base,
953                            (u32)RING_BD_SIZE,
954                            (unsigned long long)ring->cmpl_dma_base,
955                            (u32)RING_CMPL_SIZE);
956         }
957 }
958
959 static void flexrm_write_stats_in_seqfile(struct flexrm_mbox *mbox,
960                                           struct seq_file *file)
961 {
962         int i;
963         u32 val, bd_read_offset;
964         struct flexrm_ring *ring;
965
966         seq_printf(file, "%-5s %-10s %-10s %-10s %-11s %-11s\n",
967                    "Ring#", "BD_Read", "BD_Write",
968                    "Cmpl_Read", "Submitted", "Completed");
969
970         for (i = 0; i < mbox->num_rings; i++) {
971                 ring = &mbox->rings[i];
972                 bd_read_offset = readl_relaxed(ring->regs + RING_BD_READ_PTR);
973                 val = readl_relaxed(ring->regs + RING_BD_START_ADDR);
974                 bd_read_offset *= RING_DESC_SIZE;
975                 bd_read_offset += (u32)(BD_START_ADDR_DECODE(val) -
976                                         ring->bd_dma_base);
977                 seq_printf(file, "%-5d 0x%08x 0x%08x 0x%08x %-11d %-11d\n",
978                            ring->num,
979                            (u32)bd_read_offset,
980                            (u32)ring->bd_write_offset,
981                            (u32)ring->cmpl_read_offset,
982                            (u32)atomic_read(&ring->msg_send_count),
983                            (u32)atomic_read(&ring->msg_cmpl_count));
984         }
985 }
986
987 static int flexrm_new_request(struct flexrm_ring *ring,
988                                 struct brcm_message *batch_msg,
989                                 struct brcm_message *msg)
990 {
991         void *next;
992         unsigned long flags;
993         u32 val, count, nhcnt;
994         u32 read_offset, write_offset;
995         bool exit_cleanup = false;
996         int ret = 0, reqid;
997
998         /* Do sanity check on message */
999         if (!flexrm_sanity_check(msg))
1000                 return -EIO;
1001         msg->error = 0;
1002
1003         /* If no requests possible then save data pointer and goto done. */
1004         spin_lock_irqsave(&ring->lock, flags);
1005         reqid = bitmap_find_free_region(ring->requests_bmap,
1006                                         RING_MAX_REQ_COUNT, 0);
1007         spin_unlock_irqrestore(&ring->lock, flags);
1008         if (reqid < 0)
1009                 return -ENOSPC;
1010         ring->requests[reqid] = msg;
1011
1012         /* Do DMA mappings for the message */
1013         ret = flexrm_dma_map(ring->mbox->dev, msg);
1014         if (ret < 0) {
1015                 ring->requests[reqid] = NULL;
1016                 spin_lock_irqsave(&ring->lock, flags);
1017                 bitmap_release_region(ring->requests_bmap, reqid, 0);
1018                 spin_unlock_irqrestore(&ring->lock, flags);
1019                 return ret;
1020         }
1021
1022         /* Determine current HW BD read offset */
1023         read_offset = readl_relaxed(ring->regs + RING_BD_READ_PTR);
1024         val = readl_relaxed(ring->regs + RING_BD_START_ADDR);
1025         read_offset *= RING_DESC_SIZE;
1026         read_offset += (u32)(BD_START_ADDR_DECODE(val) - ring->bd_dma_base);
1027
1028         /*
1029          * Number required descriptors = number of non-header descriptors +
1030          *                               number of header descriptors +
1031          *                               1x null descriptor
1032          */
1033         nhcnt = flexrm_estimate_nonheader_desc_count(msg);
1034         count = flexrm_estimate_header_desc_count(nhcnt) + nhcnt + 1;
1035
1036         /* Check for available descriptor space. */
1037         write_offset = ring->bd_write_offset;
1038         while (count) {
1039                 if (!flexrm_is_next_table_desc(ring->bd_base + write_offset))
1040                         count--;
1041                 write_offset += RING_DESC_SIZE;
1042                 if (write_offset == RING_BD_SIZE)
1043                         write_offset = 0x0;
1044                 if (write_offset == read_offset)
1045                         break;
1046         }
1047         if (count) {
1048                 ret = -ENOSPC;
1049                 exit_cleanup = true;
1050                 goto exit;
1051         }
1052
1053         /* Write descriptors to ring */
1054         next = flexrm_write_descs(msg, nhcnt, reqid,
1055                         ring->bd_base + ring->bd_write_offset,
1056                         RING_BD_TOGGLE_VALID(ring->bd_write_offset),
1057                         ring->bd_base, ring->bd_base + RING_BD_SIZE);
1058         if (IS_ERR(next)) {
1059                 ret = PTR_ERR(next);
1060                 exit_cleanup = true;
1061                 goto exit;
1062         }
1063
1064         /* Save ring BD write offset */
1065         ring->bd_write_offset = (unsigned long)(next - ring->bd_base);
1066
1067         /* Increment number of messages sent */
1068         atomic_inc_return(&ring->msg_send_count);
1069
1070 exit:
1071         /* Update error status in message */
1072         msg->error = ret;
1073
1074         /* Cleanup if we failed */
1075         if (exit_cleanup) {
1076                 flexrm_dma_unmap(ring->mbox->dev, msg);
1077                 ring->requests[reqid] = NULL;
1078                 spin_lock_irqsave(&ring->lock, flags);
1079                 bitmap_release_region(ring->requests_bmap, reqid, 0);
1080                 spin_unlock_irqrestore(&ring->lock, flags);
1081         }
1082
1083         return ret;
1084 }
1085
1086 static int flexrm_process_completions(struct flexrm_ring *ring)
1087 {
1088         u64 desc;
1089         int err, count = 0;
1090         unsigned long flags;
1091         struct brcm_message *msg = NULL;
1092         u32 reqid, cmpl_read_offset, cmpl_write_offset;
1093         struct mbox_chan *chan = &ring->mbox->controller.chans[ring->num];
1094
1095         spin_lock_irqsave(&ring->lock, flags);
1096
1097         /*
1098          * Get current completion read and write offset
1099          *
1100          * Note: We should read completion write pointer atleast once
1101          * after we get a MSI interrupt because HW maintains internal
1102          * MSI status which will allow next MSI interrupt only after
1103          * completion write pointer is read.
1104          */
1105         cmpl_write_offset = readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
1106         cmpl_write_offset *= RING_DESC_SIZE;
1107         cmpl_read_offset = ring->cmpl_read_offset;
1108         ring->cmpl_read_offset = cmpl_write_offset;
1109
1110         spin_unlock_irqrestore(&ring->lock, flags);
1111
1112         /* For each completed request notify mailbox clients */
1113         reqid = 0;
1114         while (cmpl_read_offset != cmpl_write_offset) {
1115                 /* Dequeue next completion descriptor */
1116                 desc = *((u64 *)(ring->cmpl_base + cmpl_read_offset));
1117
1118                 /* Next read offset */
1119                 cmpl_read_offset += RING_DESC_SIZE;
1120                 if (cmpl_read_offset == RING_CMPL_SIZE)
1121                         cmpl_read_offset = 0;
1122
1123                 /* Decode error from completion descriptor */
1124                 err = flexrm_cmpl_desc_to_error(desc);
1125                 if (err < 0) {
1126                         dev_warn(ring->mbox->dev,
1127                         "ring%d got completion desc=0x%lx with error %d\n",
1128                         ring->num, (unsigned long)desc, err);
1129                 }
1130
1131                 /* Determine request id from completion descriptor */
1132                 reqid = flexrm_cmpl_desc_to_reqid(desc);
1133
1134                 /* Determine message pointer based on reqid */
1135                 msg = ring->requests[reqid];
1136                 if (!msg) {
1137                         dev_warn(ring->mbox->dev,
1138                         "ring%d null msg pointer for completion desc=0x%lx\n",
1139                         ring->num, (unsigned long)desc);
1140                         continue;
1141                 }
1142
1143                 /* Release reqid for recycling */
1144                 ring->requests[reqid] = NULL;
1145                 spin_lock_irqsave(&ring->lock, flags);
1146                 bitmap_release_region(ring->requests_bmap, reqid, 0);
1147                 spin_unlock_irqrestore(&ring->lock, flags);
1148
1149                 /* Unmap DMA mappings */
1150                 flexrm_dma_unmap(ring->mbox->dev, msg);
1151
1152                 /* Give-back message to mailbox client */
1153                 msg->error = err;
1154                 mbox_chan_received_data(chan, msg);
1155
1156                 /* Increment number of completions processed */
1157                 atomic_inc_return(&ring->msg_cmpl_count);
1158                 count++;
1159         }
1160
1161         return count;
1162 }
1163
1164 /* ====== FlexRM Debugfs callbacks ====== */
1165
1166 static int flexrm_debugfs_conf_show(struct seq_file *file, void *offset)
1167 {
1168         struct platform_device *pdev = to_platform_device(file->private);
1169         struct flexrm_mbox *mbox = platform_get_drvdata(pdev);
1170
1171         /* Write config in file */
1172         flexrm_write_config_in_seqfile(mbox, file);
1173
1174         return 0;
1175 }
1176
1177 static int flexrm_debugfs_stats_show(struct seq_file *file, void *offset)
1178 {
1179         struct platform_device *pdev = to_platform_device(file->private);
1180         struct flexrm_mbox *mbox = platform_get_drvdata(pdev);
1181
1182         /* Write stats in file */
1183         flexrm_write_stats_in_seqfile(mbox, file);
1184
1185         return 0;
1186 }
1187
1188 /* ====== FlexRM interrupt handler ===== */
1189
1190 static irqreturn_t flexrm_irq_event(int irq, void *dev_id)
1191 {
1192         /* We only have MSI for completions so just wakeup IRQ thread */
1193         /* Ring related errors will be informed via completion descriptors */
1194
1195         return IRQ_WAKE_THREAD;
1196 }
1197
1198 static irqreturn_t flexrm_irq_thread(int irq, void *dev_id)
1199 {
1200         flexrm_process_completions(dev_id);
1201
1202         return IRQ_HANDLED;
1203 }
1204
1205 /* ====== FlexRM mailbox callbacks ===== */
1206
1207 static int flexrm_send_data(struct mbox_chan *chan, void *data)
1208 {
1209         int i, rc;
1210         struct flexrm_ring *ring = chan->con_priv;
1211         struct brcm_message *msg = data;
1212
1213         if (msg->type == BRCM_MESSAGE_BATCH) {
1214                 for (i = msg->batch.msgs_queued;
1215                      i < msg->batch.msgs_count; i++) {
1216                         rc = flexrm_new_request(ring, msg,
1217                                                  &msg->batch.msgs[i]);
1218                         if (rc) {
1219                                 msg->error = rc;
1220                                 return rc;
1221                         }
1222                         msg->batch.msgs_queued++;
1223                 }
1224                 return 0;
1225         }
1226
1227         return flexrm_new_request(ring, NULL, data);
1228 }
1229
1230 static bool flexrm_peek_data(struct mbox_chan *chan)
1231 {
1232         int cnt = flexrm_process_completions(chan->con_priv);
1233
1234         return (cnt > 0) ? true : false;
1235 }
1236
1237 static int flexrm_startup(struct mbox_chan *chan)
1238 {
1239         u64 d;
1240         u32 val, off;
1241         int ret = 0;
1242         dma_addr_t next_addr;
1243         struct flexrm_ring *ring = chan->con_priv;
1244
1245         /* Allocate BD memory */
1246         ring->bd_base = dma_pool_alloc(ring->mbox->bd_pool,
1247                                        GFP_KERNEL, &ring->bd_dma_base);
1248         if (!ring->bd_base) {
1249                 dev_err(ring->mbox->dev,
1250                         "can't allocate BD memory for ring%d\n",
1251                         ring->num);
1252                 ret = -ENOMEM;
1253                 goto fail;
1254         }
1255
1256         /* Configure next table pointer entries in BD memory */
1257         for (off = 0; off < RING_BD_SIZE; off += RING_DESC_SIZE) {
1258                 next_addr = off + RING_DESC_SIZE;
1259                 if (next_addr == RING_BD_SIZE)
1260                         next_addr = 0;
1261                 next_addr += ring->bd_dma_base;
1262                 if (RING_BD_ALIGN_CHECK(next_addr))
1263                         d = flexrm_next_table_desc(RING_BD_TOGGLE_VALID(off),
1264                                                     next_addr);
1265                 else
1266                         d = flexrm_null_desc(RING_BD_TOGGLE_INVALID(off));
1267                 flexrm_write_desc(ring->bd_base + off, d);
1268         }
1269
1270         /* Allocate completion memory */
1271         ring->cmpl_base = dma_pool_zalloc(ring->mbox->cmpl_pool,
1272                                          GFP_KERNEL, &ring->cmpl_dma_base);
1273         if (!ring->cmpl_base) {
1274                 dev_err(ring->mbox->dev,
1275                         "can't allocate completion memory for ring%d\n",
1276                         ring->num);
1277                 ret = -ENOMEM;
1278                 goto fail_free_bd_memory;
1279         }
1280
1281         /* Request IRQ */
1282         if (ring->irq == UINT_MAX) {
1283                 dev_err(ring->mbox->dev,
1284                         "ring%d IRQ not available\n", ring->num);
1285                 ret = -ENODEV;
1286                 goto fail_free_cmpl_memory;
1287         }
1288         ret = request_threaded_irq(ring->irq,
1289                                    flexrm_irq_event,
1290                                    flexrm_irq_thread,
1291                                    0, dev_name(ring->mbox->dev), ring);
1292         if (ret) {
1293                 dev_err(ring->mbox->dev,
1294                         "failed to request ring%d IRQ\n", ring->num);
1295                 goto fail_free_cmpl_memory;
1296         }
1297         ring->irq_requested = true;
1298
1299         /* Set IRQ affinity hint */
1300         ring->irq_aff_hint = CPU_MASK_NONE;
1301         val = ring->mbox->num_rings;
1302         val = (num_online_cpus() < val) ? val / num_online_cpus() : 1;
1303         cpumask_set_cpu((ring->num / val) % num_online_cpus(),
1304                         &ring->irq_aff_hint);
1305         ret = irq_set_affinity_hint(ring->irq, &ring->irq_aff_hint);
1306         if (ret) {
1307                 dev_err(ring->mbox->dev,
1308                         "failed to set IRQ affinity hint for ring%d\n",
1309                         ring->num);
1310                 goto fail_free_irq;
1311         }
1312
1313         /* Disable/inactivate ring */
1314         writel_relaxed(0x0, ring->regs + RING_CONTROL);
1315
1316         /* Program BD start address */
1317         val = BD_START_ADDR_VALUE(ring->bd_dma_base);
1318         writel_relaxed(val, ring->regs + RING_BD_START_ADDR);
1319
1320         /* BD write pointer will be same as HW write pointer */
1321         ring->bd_write_offset =
1322                         readl_relaxed(ring->regs + RING_BD_WRITE_PTR);
1323         ring->bd_write_offset *= RING_DESC_SIZE;
1324
1325         /* Program completion start address */
1326         val = CMPL_START_ADDR_VALUE(ring->cmpl_dma_base);
1327         writel_relaxed(val, ring->regs + RING_CMPL_START_ADDR);
1328
1329         /* Completion read pointer will be same as HW write pointer */
1330         ring->cmpl_read_offset =
1331                         readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
1332         ring->cmpl_read_offset *= RING_DESC_SIZE;
1333
1334         /* Read ring Tx, Rx, and Outstanding counts to clear */
1335         readl_relaxed(ring->regs + RING_NUM_REQ_RECV_LS);
1336         readl_relaxed(ring->regs + RING_NUM_REQ_RECV_MS);
1337         readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_LS);
1338         readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_MS);
1339         readl_relaxed(ring->regs + RING_NUM_REQ_OUTSTAND);
1340
1341         /* Configure RING_MSI_CONTROL */
1342         val = 0;
1343         val |= (ring->msi_timer_val << MSI_TIMER_VAL_SHIFT);
1344         val |= BIT(MSI_ENABLE_SHIFT);
1345         val |= (ring->msi_count_threshold & MSI_COUNT_MASK) << MSI_COUNT_SHIFT;
1346         writel_relaxed(val, ring->regs + RING_MSI_CONTROL);
1347
1348         /* Enable/activate ring */
1349         val = BIT(CONTROL_ACTIVE_SHIFT);
1350         writel_relaxed(val, ring->regs + RING_CONTROL);
1351
1352         /* Reset stats to zero */
1353         atomic_set(&ring->msg_send_count, 0);
1354         atomic_set(&ring->msg_cmpl_count, 0);
1355
1356         return 0;
1357
1358 fail_free_irq:
1359         free_irq(ring->irq, ring);
1360         ring->irq_requested = false;
1361 fail_free_cmpl_memory:
1362         dma_pool_free(ring->mbox->cmpl_pool,
1363                       ring->cmpl_base, ring->cmpl_dma_base);
1364         ring->cmpl_base = NULL;
1365 fail_free_bd_memory:
1366         dma_pool_free(ring->mbox->bd_pool,
1367                       ring->bd_base, ring->bd_dma_base);
1368         ring->bd_base = NULL;
1369 fail:
1370         return ret;
1371 }
1372
1373 static void flexrm_shutdown(struct mbox_chan *chan)
1374 {
1375         u32 reqid;
1376         unsigned int timeout;
1377         struct brcm_message *msg;
1378         struct flexrm_ring *ring = chan->con_priv;
1379
1380         /* Disable/inactivate ring */
1381         writel_relaxed(0x0, ring->regs + RING_CONTROL);
1382
1383         /* Set ring flush state */
1384         timeout = 1000; /* timeout of 1s */
1385         writel_relaxed(BIT(CONTROL_FLUSH_SHIFT),
1386                         ring->regs + RING_CONTROL);
1387         do {
1388                 if (readl_relaxed(ring->regs + RING_FLUSH_DONE) &
1389                     FLUSH_DONE_MASK)
1390                         break;
1391                 mdelay(1);
1392         } while (--timeout);
1393         if (!timeout)
1394                 dev_err(ring->mbox->dev,
1395                         "setting ring%d flush state timedout\n", ring->num);
1396
1397         /* Clear ring flush state */
1398         timeout = 1000; /* timeout of 1s */
1399         writel_relaxed(0x0, ring + RING_CONTROL);
1400         do {
1401                 if (!(readl_relaxed(ring + RING_FLUSH_DONE) &
1402                       FLUSH_DONE_MASK))
1403                         break;
1404                 mdelay(1);
1405         } while (--timeout);
1406         if (!timeout)
1407                 dev_err(ring->mbox->dev,
1408                         "clearing ring%d flush state timedout\n", ring->num);
1409
1410         /* Abort all in-flight requests */
1411         for (reqid = 0; reqid < RING_MAX_REQ_COUNT; reqid++) {
1412                 msg = ring->requests[reqid];
1413                 if (!msg)
1414                         continue;
1415
1416                 /* Release reqid for recycling */
1417                 ring->requests[reqid] = NULL;
1418
1419                 /* Unmap DMA mappings */
1420                 flexrm_dma_unmap(ring->mbox->dev, msg);
1421
1422                 /* Give-back message to mailbox client */
1423                 msg->error = -EIO;
1424                 mbox_chan_received_data(chan, msg);
1425         }
1426
1427         /* Clear requests bitmap */
1428         bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT);
1429
1430         /* Release IRQ */
1431         if (ring->irq_requested) {
1432                 irq_set_affinity_hint(ring->irq, NULL);
1433                 free_irq(ring->irq, ring);
1434                 ring->irq_requested = false;
1435         }
1436
1437         /* Free-up completion descriptor ring */
1438         if (ring->cmpl_base) {
1439                 dma_pool_free(ring->mbox->cmpl_pool,
1440                               ring->cmpl_base, ring->cmpl_dma_base);
1441                 ring->cmpl_base = NULL;
1442         }
1443
1444         /* Free-up BD descriptor ring */
1445         if (ring->bd_base) {
1446                 dma_pool_free(ring->mbox->bd_pool,
1447                               ring->bd_base, ring->bd_dma_base);
1448                 ring->bd_base = NULL;
1449         }
1450 }
1451
1452 static const struct mbox_chan_ops flexrm_mbox_chan_ops = {
1453         .send_data      = flexrm_send_data,
1454         .startup        = flexrm_startup,
1455         .shutdown       = flexrm_shutdown,
1456         .peek_data      = flexrm_peek_data,
1457 };
1458
1459 static struct mbox_chan *flexrm_mbox_of_xlate(struct mbox_controller *cntlr,
1460                                         const struct of_phandle_args *pa)
1461 {
1462         struct mbox_chan *chan;
1463         struct flexrm_ring *ring;
1464
1465         if (pa->args_count < 3)
1466                 return ERR_PTR(-EINVAL);
1467
1468         if (pa->args[0] >= cntlr->num_chans)
1469                 return ERR_PTR(-ENOENT);
1470
1471         if (pa->args[1] > MSI_COUNT_MASK)
1472                 return ERR_PTR(-EINVAL);
1473
1474         if (pa->args[2] > MSI_TIMER_VAL_MASK)
1475                 return ERR_PTR(-EINVAL);
1476
1477         chan = &cntlr->chans[pa->args[0]];
1478         ring = chan->con_priv;
1479         ring->msi_count_threshold = pa->args[1];
1480         ring->msi_timer_val = pa->args[2];
1481
1482         return chan;
1483 }
1484
1485 /* ====== FlexRM platform driver ===== */
1486
1487 static void flexrm_mbox_msi_write(struct msi_desc *desc, struct msi_msg *msg)
1488 {
1489         struct device *dev = msi_desc_to_dev(desc);
1490         struct flexrm_mbox *mbox = dev_get_drvdata(dev);
1491         struct flexrm_ring *ring = &mbox->rings[desc->platform.msi_index];
1492
1493         /* Configure per-Ring MSI registers */
1494         writel_relaxed(msg->address_lo, ring->regs + RING_MSI_ADDR_LS);
1495         writel_relaxed(msg->address_hi, ring->regs + RING_MSI_ADDR_MS);
1496         writel_relaxed(msg->data, ring->regs + RING_MSI_DATA_VALUE);
1497 }
1498
1499 static int flexrm_mbox_probe(struct platform_device *pdev)
1500 {
1501         int index, ret = 0;
1502         void __iomem *regs;
1503         void __iomem *regs_end;
1504         struct msi_desc *desc;
1505         struct resource *iomem;
1506         struct flexrm_ring *ring;
1507         struct flexrm_mbox *mbox;
1508         struct device *dev = &pdev->dev;
1509
1510         /* Allocate driver mailbox struct */
1511         mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
1512         if (!mbox) {
1513                 ret = -ENOMEM;
1514                 goto fail;
1515         }
1516         mbox->dev = dev;
1517         platform_set_drvdata(pdev, mbox);
1518
1519         /* Get resource for registers */
1520         iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1521         if (!iomem || (resource_size(iomem) < RING_REGS_SIZE)) {
1522                 ret = -ENODEV;
1523                 goto fail;
1524         }
1525
1526         /* Map registers of all rings */
1527         mbox->regs = devm_ioremap_resource(&pdev->dev, iomem);
1528         if (IS_ERR(mbox->regs)) {
1529                 ret = PTR_ERR(mbox->regs);
1530                 dev_err(&pdev->dev, "Failed to remap mailbox regs: %d\n", ret);
1531                 goto fail;
1532         }
1533         regs_end = mbox->regs + resource_size(iomem);
1534
1535         /* Scan and count available rings */
1536         mbox->num_rings = 0;
1537         for (regs = mbox->regs; regs < regs_end; regs += RING_REGS_SIZE) {
1538                 if (readl_relaxed(regs + RING_VER) == RING_VER_MAGIC)
1539                         mbox->num_rings++;
1540         }
1541         if (!mbox->num_rings) {
1542                 ret = -ENODEV;
1543                 goto fail;
1544         }
1545
1546         /* Allocate driver ring structs */
1547         ring = devm_kcalloc(dev, mbox->num_rings, sizeof(*ring), GFP_KERNEL);
1548         if (!ring) {
1549                 ret = -ENOMEM;
1550                 goto fail;
1551         }
1552         mbox->rings = ring;
1553
1554         /* Initialize members of driver ring structs */
1555         regs = mbox->regs;
1556         for (index = 0; index < mbox->num_rings; index++) {
1557                 ring = &mbox->rings[index];
1558                 ring->num = index;
1559                 ring->mbox = mbox;
1560                 while ((regs < regs_end) &&
1561                        (readl_relaxed(regs + RING_VER) != RING_VER_MAGIC))
1562                         regs += RING_REGS_SIZE;
1563                 if (regs_end <= regs) {
1564                         ret = -ENODEV;
1565                         goto fail;
1566                 }
1567                 ring->regs = regs;
1568                 regs += RING_REGS_SIZE;
1569                 ring->irq = UINT_MAX;
1570                 ring->irq_requested = false;
1571                 ring->msi_timer_val = MSI_TIMER_VAL_MASK;
1572                 ring->msi_count_threshold = 0x1;
1573                 memset(ring->requests, 0, sizeof(ring->requests));
1574                 ring->bd_base = NULL;
1575                 ring->bd_dma_base = 0;
1576                 ring->cmpl_base = NULL;
1577                 ring->cmpl_dma_base = 0;
1578                 atomic_set(&ring->msg_send_count, 0);
1579                 atomic_set(&ring->msg_cmpl_count, 0);
1580                 spin_lock_init(&ring->lock);
1581                 bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT);
1582                 ring->cmpl_read_offset = 0;
1583         }
1584
1585         /* FlexRM is capable of 40-bit physical addresses only */
1586         ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(40));
1587         if (ret) {
1588                 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
1589                 if (ret)
1590                         goto fail;
1591         }
1592
1593         /* Create DMA pool for ring BD memory */
1594         mbox->bd_pool = dma_pool_create("bd", dev, RING_BD_SIZE,
1595                                         1 << RING_BD_ALIGN_ORDER, 0);
1596         if (!mbox->bd_pool) {
1597                 ret = -ENOMEM;
1598                 goto fail;
1599         }
1600
1601         /* Create DMA pool for ring completion memory */
1602         mbox->cmpl_pool = dma_pool_create("cmpl", dev, RING_CMPL_SIZE,
1603                                           1 << RING_CMPL_ALIGN_ORDER, 0);
1604         if (!mbox->cmpl_pool) {
1605                 ret = -ENOMEM;
1606                 goto fail_destroy_bd_pool;
1607         }
1608
1609         /* Allocate platform MSIs for each ring */
1610         ret = platform_msi_domain_alloc_irqs(dev, mbox->num_rings,
1611                                                 flexrm_mbox_msi_write);
1612         if (ret)
1613                 goto fail_destroy_cmpl_pool;
1614
1615         /* Save alloced IRQ numbers for each ring */
1616         for_each_msi_entry(desc, dev) {
1617                 ring = &mbox->rings[desc->platform.msi_index];
1618                 ring->irq = desc->irq;
1619         }
1620
1621         /* Check availability of debugfs */
1622         if (!debugfs_initialized())
1623                 goto skip_debugfs;
1624
1625         /* Create debugfs root entry */
1626         mbox->root = debugfs_create_dir(dev_name(mbox->dev), NULL);
1627         if (IS_ERR_OR_NULL(mbox->root)) {
1628                 ret = PTR_ERR_OR_ZERO(mbox->root);
1629                 goto fail_free_msis;
1630         }
1631
1632         /* Create debugfs config entry */
1633         mbox->config = debugfs_create_devm_seqfile(mbox->dev,
1634                                                    "config", mbox->root,
1635                                                    flexrm_debugfs_conf_show);
1636         if (IS_ERR_OR_NULL(mbox->config)) {
1637                 ret = PTR_ERR_OR_ZERO(mbox->config);
1638                 goto fail_free_debugfs_root;
1639         }
1640
1641         /* Create debugfs stats entry */
1642         mbox->stats = debugfs_create_devm_seqfile(mbox->dev,
1643                                                   "stats", mbox->root,
1644                                                   flexrm_debugfs_stats_show);
1645         if (IS_ERR_OR_NULL(mbox->stats)) {
1646                 ret = PTR_ERR_OR_ZERO(mbox->stats);
1647                 goto fail_free_debugfs_root;
1648         }
1649 skip_debugfs:
1650
1651         /* Initialize mailbox controller */
1652         mbox->controller.txdone_irq = false;
1653         mbox->controller.txdone_poll = false;
1654         mbox->controller.ops = &flexrm_mbox_chan_ops;
1655         mbox->controller.dev = dev;
1656         mbox->controller.num_chans = mbox->num_rings;
1657         mbox->controller.of_xlate = flexrm_mbox_of_xlate;
1658         mbox->controller.chans = devm_kcalloc(dev, mbox->num_rings,
1659                                 sizeof(*mbox->controller.chans), GFP_KERNEL);
1660         if (!mbox->controller.chans) {
1661                 ret = -ENOMEM;
1662                 goto fail_free_debugfs_root;
1663         }
1664         for (index = 0; index < mbox->num_rings; index++)
1665                 mbox->controller.chans[index].con_priv = &mbox->rings[index];
1666
1667         /* Register mailbox controller */
1668         ret = devm_mbox_controller_register(dev, &mbox->controller);
1669         if (ret)
1670                 goto fail_free_debugfs_root;
1671
1672         dev_info(dev, "registered flexrm mailbox with %d channels\n",
1673                         mbox->controller.num_chans);
1674
1675         return 0;
1676
1677 fail_free_debugfs_root:
1678         debugfs_remove_recursive(mbox->root);
1679 fail_free_msis:
1680         platform_msi_domain_free_irqs(dev);
1681 fail_destroy_cmpl_pool:
1682         dma_pool_destroy(mbox->cmpl_pool);
1683 fail_destroy_bd_pool:
1684         dma_pool_destroy(mbox->bd_pool);
1685 fail:
1686         return ret;
1687 }
1688
1689 static int flexrm_mbox_remove(struct platform_device *pdev)
1690 {
1691         struct device *dev = &pdev->dev;
1692         struct flexrm_mbox *mbox = platform_get_drvdata(pdev);
1693
1694         debugfs_remove_recursive(mbox->root);
1695
1696         platform_msi_domain_free_irqs(dev);
1697
1698         dma_pool_destroy(mbox->cmpl_pool);
1699         dma_pool_destroy(mbox->bd_pool);
1700
1701         return 0;
1702 }
1703
1704 static const struct of_device_id flexrm_mbox_of_match[] = {
1705         { .compatible = "brcm,iproc-flexrm-mbox", },
1706         {},
1707 };
1708 MODULE_DEVICE_TABLE(of, flexrm_mbox_of_match);
1709
1710 static struct platform_driver flexrm_mbox_driver = {
1711         .driver = {
1712                 .name = "brcm-flexrm-mbox",
1713                 .of_match_table = flexrm_mbox_of_match,
1714         },
1715         .probe          = flexrm_mbox_probe,
1716         .remove         = flexrm_mbox_remove,
1717 };
1718 module_platform_driver(flexrm_mbox_driver);
1719
1720 MODULE_AUTHOR("Anup Patel <anup.patel@broadcom.com>");
1721 MODULE_DESCRIPTION("Broadcom FlexRM mailbox driver");
1722 MODULE_LICENSE("GPL v2");