1// SPDX-License-Identifier: GPL-2.0-only
2// Copyright (C) 2017 Broadcom
3
4/*
5 * Broadcom FlexRM Mailbox Driver
6 *
7 * Each Broadcom FlexSparx4 offload engine is implemented as an
8 * extension to Broadcom FlexRM ring manager. The FlexRM ring
9 * manager provides a set of rings which can be used to submit
10 * work to a FlexSparx4 offload engine.
11 *
12 * This driver creates a mailbox controller using a set of FlexRM
13 * rings where each mailbox channel represents a separate FlexRM ring.
14 */
15
16#include <asm/barrier.h>
17#include <asm/byteorder.h>
18#include <linux/atomic.h>
19#include <linux/bitmap.h>
20#include <linux/debugfs.h>
21#include <linux/delay.h>
22#include <linux/device.h>
23#include <linux/dma-mapping.h>
24#include <linux/dmapool.h>
25#include <linux/err.h>
26#include <linux/interrupt.h>
27#include <linux/kernel.h>
28#include <linux/mailbox_controller.h>
29#include <linux/mailbox_client.h>
30#include <linux/mailbox/brcm-message.h>
31#include <linux/module.h>
32#include <linux/msi.h>
33#include <linux/of_address.h>
34#include <linux/of_irq.h>
35#include <linux/platform_device.h>
36#include <linux/spinlock.h>
37
38/* ====== FlexRM register defines ===== */
39
40/* FlexRM configuration */
41#define RING_REGS_SIZE					0x10000
42#define RING_DESC_SIZE					8
43#define RING_DESC_INDEX(offset)				\
44			((offset) / RING_DESC_SIZE)
45#define RING_DESC_OFFSET(index)				\
46			((index) * RING_DESC_SIZE)
47#define RING_MAX_REQ_COUNT				1024
48#define RING_BD_ALIGN_ORDER				12
49#define RING_BD_ALIGN_CHECK(addr)			\
50			(!((addr) & ((0x1 << RING_BD_ALIGN_ORDER) - 1)))
51#define RING_BD_TOGGLE_INVALID(offset)			\
52			(((offset) >> RING_BD_ALIGN_ORDER) & 0x1)
53#define RING_BD_TOGGLE_VALID(offset)			\
54			(!RING_BD_TOGGLE_INVALID(offset))
55#define RING_BD_DESC_PER_REQ				32
56#define RING_BD_DESC_COUNT				\
57			(RING_MAX_REQ_COUNT * RING_BD_DESC_PER_REQ)
58#define RING_BD_SIZE					\
59			(RING_BD_DESC_COUNT * RING_DESC_SIZE)
60#define RING_CMPL_ALIGN_ORDER				13
61#define RING_CMPL_DESC_COUNT				RING_MAX_REQ_COUNT
62#define RING_CMPL_SIZE					\
63			(RING_CMPL_DESC_COUNT * RING_DESC_SIZE)
64#define RING_VER_MAGIC					0x76303031
65
66/* Per-Ring register offsets */
67#define RING_VER					0x000
68#define RING_BD_START_ADDR				0x004
69#define RING_BD_READ_PTR				0x008
70#define RING_BD_WRITE_PTR				0x00c
71#define RING_BD_READ_PTR_DDR_LS				0x010
72#define RING_BD_READ_PTR_DDR_MS				0x014
73#define RING_CMPL_START_ADDR				0x018
74#define RING_CMPL_WRITE_PTR				0x01c
75#define RING_NUM_REQ_RECV_LS				0x020
76#define RING_NUM_REQ_RECV_MS				0x024
77#define RING_NUM_REQ_TRANS_LS				0x028
78#define RING_NUM_REQ_TRANS_MS				0x02c
79#define RING_NUM_REQ_OUTSTAND				0x030
80#define RING_CONTROL					0x034
81#define RING_FLUSH_DONE					0x038
82#define RING_MSI_ADDR_LS				0x03c
83#define RING_MSI_ADDR_MS				0x040
84#define RING_MSI_CONTROL				0x048
85#define RING_BD_READ_PTR_DDR_CONTROL			0x04c
86#define RING_MSI_DATA_VALUE				0x064
87
88/* Register RING_BD_START_ADDR fields */
89#define BD_LAST_UPDATE_HW_SHIFT				28
90#define BD_LAST_UPDATE_HW_MASK				0x1
91#define BD_START_ADDR_VALUE(pa)				\
92	((u32)((((dma_addr_t)(pa)) >> RING_BD_ALIGN_ORDER) & 0x0fffffff))
93#define BD_START_ADDR_DECODE(val)			\
94	((dma_addr_t)((val) & 0x0fffffff) << RING_BD_ALIGN_ORDER)
95
96/* Register RING_CMPL_START_ADDR fields */
97#define CMPL_START_ADDR_VALUE(pa)			\
98	((u32)((((u64)(pa)) >> RING_CMPL_ALIGN_ORDER) & 0x07ffffff))
99
100/* Register RING_CONTROL fields */
101#define CONTROL_MASK_DISABLE_CONTROL			12
102#define CONTROL_FLUSH_SHIFT				5
103#define CONTROL_ACTIVE_SHIFT				4
104#define CONTROL_RATE_ADAPT_MASK				0xf
105#define CONTROL_RATE_DYNAMIC				0x0
106#define CONTROL_RATE_FAST				0x8
107#define CONTROL_RATE_MEDIUM				0x9
108#define CONTROL_RATE_SLOW				0xa
109#define CONTROL_RATE_IDLE				0xb
110
111/* Register RING_FLUSH_DONE fields */
112#define FLUSH_DONE_MASK					0x1
113
114/* Register RING_MSI_CONTROL fields */
115#define MSI_TIMER_VAL_SHIFT				16
116#define MSI_TIMER_VAL_MASK				0xffff
117#define MSI_ENABLE_SHIFT				15
118#define MSI_ENABLE_MASK					0x1
119#define MSI_COUNT_SHIFT					0
120#define MSI_COUNT_MASK					0x3ff
121
122/* Register RING_BD_READ_PTR_DDR_CONTROL fields */
123#define BD_READ_PTR_DDR_TIMER_VAL_SHIFT			16
124#define BD_READ_PTR_DDR_TIMER_VAL_MASK			0xffff
125#define BD_READ_PTR_DDR_ENABLE_SHIFT			15
126#define BD_READ_PTR_DDR_ENABLE_MASK			0x1
127
128/* ====== FlexRM ring descriptor defines ===== */
129
130/* Completion descriptor format */
131#define CMPL_OPAQUE_SHIFT			0
132#define CMPL_OPAQUE_MASK			0xffff
133#define CMPL_ENGINE_STATUS_SHIFT		16
134#define CMPL_ENGINE_STATUS_MASK			0xffff
135#define CMPL_DME_STATUS_SHIFT			32
136#define CMPL_DME_STATUS_MASK			0xffff
137#define CMPL_RM_STATUS_SHIFT			48
138#define CMPL_RM_STATUS_MASK			0xffff
139
140/* Completion DME status code */
141#define DME_STATUS_MEM_COR_ERR			BIT(0)
142#define DME_STATUS_MEM_UCOR_ERR			BIT(1)
143#define DME_STATUS_FIFO_UNDERFLOW		BIT(2)
144#define DME_STATUS_FIFO_OVERFLOW		BIT(3)
145#define DME_STATUS_RRESP_ERR			BIT(4)
146#define DME_STATUS_BRESP_ERR			BIT(5)
147#define DME_STATUS_ERROR_MASK			(DME_STATUS_MEM_COR_ERR | \
148						 DME_STATUS_MEM_UCOR_ERR | \
149						 DME_STATUS_FIFO_UNDERFLOW | \
150						 DME_STATUS_FIFO_OVERFLOW | \
151						 DME_STATUS_RRESP_ERR | \
152						 DME_STATUS_BRESP_ERR)
153
154/* Completion RM status code */
155#define RM_STATUS_CODE_SHIFT			0
156#define RM_STATUS_CODE_MASK			0x3ff
157#define RM_STATUS_CODE_GOOD			0x0
158#define RM_STATUS_CODE_AE_TIMEOUT		0x3ff
159
160/* General descriptor format */
161#define DESC_TYPE_SHIFT				60
162#define DESC_TYPE_MASK				0xf
163#define DESC_PAYLOAD_SHIFT			0
164#define DESC_PAYLOAD_MASK			0x0fffffffffffffff
165
166/* Null descriptor format  */
167#define NULL_TYPE				0
168#define NULL_TOGGLE_SHIFT			58
169#define NULL_TOGGLE_MASK			0x1
170
171/* Header descriptor format */
172#define HEADER_TYPE				1
173#define HEADER_TOGGLE_SHIFT			58
174#define HEADER_TOGGLE_MASK			0x1
175#define HEADER_ENDPKT_SHIFT			57
176#define HEADER_ENDPKT_MASK			0x1
177#define HEADER_STARTPKT_SHIFT			56
178#define HEADER_STARTPKT_MASK			0x1
179#define HEADER_BDCOUNT_SHIFT			36
180#define HEADER_BDCOUNT_MASK			0x1f
181#define HEADER_BDCOUNT_MAX			HEADER_BDCOUNT_MASK
182#define HEADER_FLAGS_SHIFT			16
183#define HEADER_FLAGS_MASK			0xffff
184#define HEADER_OPAQUE_SHIFT			0
185#define HEADER_OPAQUE_MASK			0xffff
186
187/* Source (SRC) descriptor format */
188#define SRC_TYPE				2
189#define SRC_LENGTH_SHIFT			44
190#define SRC_LENGTH_MASK				0xffff
191#define SRC_ADDR_SHIFT				0
192#define SRC_ADDR_MASK				0x00000fffffffffff
193
194/* Destination (DST) descriptor format */
195#define DST_TYPE				3
196#define DST_LENGTH_SHIFT			44
197#define DST_LENGTH_MASK				0xffff
198#define DST_ADDR_SHIFT				0
199#define DST_ADDR_MASK				0x00000fffffffffff
200
201/* Immediate (IMM) descriptor format */
202#define IMM_TYPE				4
203#define IMM_DATA_SHIFT				0
204#define IMM_DATA_MASK				0x0fffffffffffffff
205
206/* Next pointer (NPTR) descriptor format */
207#define NPTR_TYPE				5
208#define NPTR_TOGGLE_SHIFT			58
209#define NPTR_TOGGLE_MASK			0x1
210#define NPTR_ADDR_SHIFT				0
211#define NPTR_ADDR_MASK				0x00000fffffffffff
212
213/* Mega source (MSRC) descriptor format */
214#define MSRC_TYPE				6
215#define MSRC_LENGTH_SHIFT			44
216#define MSRC_LENGTH_MASK			0xffff
217#define MSRC_ADDR_SHIFT				0
218#define MSRC_ADDR_MASK				0x00000fffffffffff
219
220/* Mega destination (MDST) descriptor format */
221#define MDST_TYPE				7
222#define MDST_LENGTH_SHIFT			44
223#define MDST_LENGTH_MASK			0xffff
224#define MDST_ADDR_SHIFT				0
225#define MDST_ADDR_MASK				0x00000fffffffffff
226
227/* Source with tlast (SRCT) descriptor format */
228#define SRCT_TYPE				8
229#define SRCT_LENGTH_SHIFT			44
230#define SRCT_LENGTH_MASK			0xffff
231#define SRCT_ADDR_SHIFT				0
232#define SRCT_ADDR_MASK				0x00000fffffffffff
233
234/* Destination with tlast (DSTT) descriptor format */
235#define DSTT_TYPE				9
236#define DSTT_LENGTH_SHIFT			44
237#define DSTT_LENGTH_MASK			0xffff
238#define DSTT_ADDR_SHIFT				0
239#define DSTT_ADDR_MASK				0x00000fffffffffff
240
241/* Immediate with tlast (IMMT) descriptor format */
242#define IMMT_TYPE				10
243#define IMMT_DATA_SHIFT				0
244#define IMMT_DATA_MASK				0x0fffffffffffffff
245
246/* Descriptor helper macros */
247#define DESC_DEC(_d, _s, _m)			(((_d) >> (_s)) & (_m))
248#define DESC_ENC(_d, _v, _s, _m)		\
249			do { \
250				(_d) &= ~((u64)(_m) << (_s)); \
251				(_d) |= (((u64)(_v) & (_m)) << (_s)); \
252			} while (0)
253
254/* ====== FlexRM data structures ===== */
255
256struct flexrm_ring {
257	/* Unprotected members */
258	int num;
259	struct flexrm_mbox *mbox;
260	void __iomem *regs;
261	bool irq_requested;
262	unsigned int irq;
263	cpumask_t irq_aff_hint;
264	unsigned int msi_timer_val;
265	unsigned int msi_count_threshold;
266	struct brcm_message *requests[RING_MAX_REQ_COUNT];
267	void *bd_base;
268	dma_addr_t bd_dma_base;
269	u32 bd_write_offset;
270	void *cmpl_base;
271	dma_addr_t cmpl_dma_base;
272	/* Atomic stats */
273	atomic_t msg_send_count;
274	atomic_t msg_cmpl_count;
275	/* Protected members */
276	spinlock_t lock;
277	DECLARE_BITMAP(requests_bmap, RING_MAX_REQ_COUNT);
278	u32 cmpl_read_offset;
279};
280
281struct flexrm_mbox {
282	struct device *dev;
283	void __iomem *regs;
284	u32 num_rings;
285	struct flexrm_ring *rings;
286	struct dma_pool *bd_pool;
287	struct dma_pool *cmpl_pool;
288	struct dentry *root;
289	struct mbox_controller controller;
290};
291
292/* ====== FlexRM ring descriptor helper routines ===== */
293
294static u64 flexrm_read_desc(void *desc_ptr)
295{
296	return le64_to_cpu(*((u64 *)desc_ptr));
297}
298
299static void flexrm_write_desc(void *desc_ptr, u64 desc)
300{
301	*((u64 *)desc_ptr) = cpu_to_le64(desc);
302}
303
304static u32 flexrm_cmpl_desc_to_reqid(u64 cmpl_desc)
305{
306	return (u32)(cmpl_desc & CMPL_OPAQUE_MASK);
307}
308
309static int flexrm_cmpl_desc_to_error(u64 cmpl_desc)
310{
311	u32 status;
312
313	status = DESC_DEC(cmpl_desc, CMPL_DME_STATUS_SHIFT,
314			  CMPL_DME_STATUS_MASK);
315	if (status & DME_STATUS_ERROR_MASK)
316		return -EIO;
317
318	status = DESC_DEC(cmpl_desc, CMPL_RM_STATUS_SHIFT,
319			  CMPL_RM_STATUS_MASK);
320	status &= RM_STATUS_CODE_MASK;
321	if (status == RM_STATUS_CODE_AE_TIMEOUT)
322		return -ETIMEDOUT;
323
324	return 0;
325}
326
327static bool flexrm_is_next_table_desc(void *desc_ptr)
328{
329	u64 desc = flexrm_read_desc(desc_ptr);
330	u32 type = DESC_DEC(desc, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
331
332	return (type == NPTR_TYPE) ? true : false;
333}
334
335static u64 flexrm_next_table_desc(u32 toggle, dma_addr_t next_addr)
336{
337	u64 desc = 0;
338
339	DESC_ENC(desc, NPTR_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
340	DESC_ENC(desc, toggle, NPTR_TOGGLE_SHIFT, NPTR_TOGGLE_MASK);
341	DESC_ENC(desc, next_addr, NPTR_ADDR_SHIFT, NPTR_ADDR_MASK);
342
343	return desc;
344}
345
346static u64 flexrm_null_desc(u32 toggle)
347{
348	u64 desc = 0;
349
350	DESC_ENC(desc, NULL_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
351	DESC_ENC(desc, toggle, NULL_TOGGLE_SHIFT, NULL_TOGGLE_MASK);
352
353	return desc;
354}
355
356static u32 flexrm_estimate_header_desc_count(u32 nhcnt)
357{
358	u32 hcnt = nhcnt / HEADER_BDCOUNT_MAX;
359
360	if (!(nhcnt % HEADER_BDCOUNT_MAX))
361		hcnt += 1;
362
363	return hcnt;
364}
365
366static void flexrm_flip_header_toggle(void *desc_ptr)
367{
368	u64 desc = flexrm_read_desc(desc_ptr);
369
370	if (desc & ((u64)0x1 << HEADER_TOGGLE_SHIFT))
371		desc &= ~((u64)0x1 << HEADER_TOGGLE_SHIFT);
372	else
373		desc |= ((u64)0x1 << HEADER_TOGGLE_SHIFT);
374
375	flexrm_write_desc(desc_ptr, desc);
376}
377
378static u64 flexrm_header_desc(u32 toggle, u32 startpkt, u32 endpkt,
379			       u32 bdcount, u32 flags, u32 opaque)
380{
381	u64 desc = 0;
382
383	DESC_ENC(desc, HEADER_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
384	DESC_ENC(desc, toggle, HEADER_TOGGLE_SHIFT, HEADER_TOGGLE_MASK);
385	DESC_ENC(desc, startpkt, HEADER_STARTPKT_SHIFT, HEADER_STARTPKT_MASK);
386	DESC_ENC(desc, endpkt, HEADER_ENDPKT_SHIFT, HEADER_ENDPKT_MASK);
387	DESC_ENC(desc, bdcount, HEADER_BDCOUNT_SHIFT, HEADER_BDCOUNT_MASK);
388	DESC_ENC(desc, flags, HEADER_FLAGS_SHIFT, HEADER_FLAGS_MASK);
389	DESC_ENC(desc, opaque, HEADER_OPAQUE_SHIFT, HEADER_OPAQUE_MASK);
390
391	return desc;
392}
393
394static void flexrm_enqueue_desc(u32 nhpos, u32 nhcnt, u32 reqid,
395				 u64 desc, void **desc_ptr, u32 *toggle,
396				 void *start_desc, void *end_desc)
397{
398	u64 d;
399	u32 nhavail, _toggle, _startpkt, _endpkt, _bdcount;
400
401	/* Sanity check */
402	if (nhcnt <= nhpos)
403		return;
404
405	/*
406	 * Each request or packet start with a HEADER descriptor followed
407	 * by one or more non-HEADER descriptors (SRC, SRCT, MSRC, DST,
408	 * DSTT, MDST, IMM, and IMMT). The number of non-HEADER descriptors
409	 * following a HEADER descriptor is represented by BDCOUNT field
410	 * of HEADER descriptor. The max value of BDCOUNT field is 31 which
411	 * means we can only have 31 non-HEADER descriptors following one
412	 * HEADER descriptor.
413	 *
414	 * In general use, number of non-HEADER descriptors can easily go
415	 * beyond 31. To tackle this situation, we have packet (or request)
416	 * extension bits (STARTPKT and ENDPKT) in the HEADER descriptor.
417	 *
418	 * To use packet extension, the first HEADER descriptor of request
419	 * (or packet) will have STARTPKT=1 and ENDPKT=0. The intermediate
420	 * HEADER descriptors will have STARTPKT=0 and ENDPKT=0. The last
421	 * HEADER descriptor will have STARTPKT=0 and ENDPKT=1. Also, the
422	 * TOGGLE bit of the first HEADER will be set to invalid state to
423	 * ensure that FlexRM does not start fetching descriptors till all
424	 * descriptors are enqueued. The user of this function will flip
425	 * the TOGGLE bit of first HEADER after all descriptors are
426	 * enqueued.
427	 */
428
429	if ((nhpos % HEADER_BDCOUNT_MAX == 0) && (nhcnt - nhpos)) {
430		/* Prepare the header descriptor */
431		nhavail = (nhcnt - nhpos);
432		_toggle = (nhpos == 0) ? !(*toggle) : (*toggle);
433		_startpkt = (nhpos == 0) ? 0x1 : 0x0;
434		_endpkt = (nhavail <= HEADER_BDCOUNT_MAX) ? 0x1 : 0x0;
435		_bdcount = (nhavail <= HEADER_BDCOUNT_MAX) ?
436				nhavail : HEADER_BDCOUNT_MAX;
437		if (nhavail <= HEADER_BDCOUNT_MAX)
438			_bdcount = nhavail;
439		else
440			_bdcount = HEADER_BDCOUNT_MAX;
441		d = flexrm_header_desc(_toggle, _startpkt, _endpkt,
442					_bdcount, 0x0, reqid);
443
444		/* Write header descriptor */
445		flexrm_write_desc(*desc_ptr, d);
446
447		/* Point to next descriptor */
448		*desc_ptr += sizeof(desc);
449		if (*desc_ptr == end_desc)
450			*desc_ptr = start_desc;
451
452		/* Skip next pointer descriptors */
453		while (flexrm_is_next_table_desc(*desc_ptr)) {
454			*toggle = (*toggle) ? 0 : 1;
455			*desc_ptr += sizeof(desc);
456			if (*desc_ptr == end_desc)
457				*desc_ptr = start_desc;
458		}
459	}
460
461	/* Write desired descriptor */
462	flexrm_write_desc(*desc_ptr, desc);
463
464	/* Point to next descriptor */
465	*desc_ptr += sizeof(desc);
466	if (*desc_ptr == end_desc)
467		*desc_ptr = start_desc;
468
469	/* Skip next pointer descriptors */
470	while (flexrm_is_next_table_desc(*desc_ptr)) {
471		*toggle = (*toggle) ? 0 : 1;
472		*desc_ptr += sizeof(desc);
473		if (*desc_ptr == end_desc)
474			*desc_ptr = start_desc;
475	}
476}
477
478static u64 flexrm_src_desc(dma_addr_t addr, unsigned int length)
479{
480	u64 desc = 0;
481
482	DESC_ENC(desc, SRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
483	DESC_ENC(desc, length, SRC_LENGTH_SHIFT, SRC_LENGTH_MASK);
484	DESC_ENC(desc, addr, SRC_ADDR_SHIFT, SRC_ADDR_MASK);
485
486	return desc;
487}
488
489static u64 flexrm_msrc_desc(dma_addr_t addr, unsigned int length_div_16)
490{
491	u64 desc = 0;
492
493	DESC_ENC(desc, MSRC_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
494	DESC_ENC(desc, length_div_16, MSRC_LENGTH_SHIFT, MSRC_LENGTH_MASK);
495	DESC_ENC(desc, addr, MSRC_ADDR_SHIFT, MSRC_ADDR_MASK);
496
497	return desc;
498}
499
500static u64 flexrm_dst_desc(dma_addr_t addr, unsigned int length)
501{
502	u64 desc = 0;
503
504	DESC_ENC(desc, DST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
505	DESC_ENC(desc, length, DST_LENGTH_SHIFT, DST_LENGTH_MASK);
506	DESC_ENC(desc, addr, DST_ADDR_SHIFT, DST_ADDR_MASK);
507
508	return desc;
509}
510
511static u64 flexrm_mdst_desc(dma_addr_t addr, unsigned int length_div_16)
512{
513	u64 desc = 0;
514
515	DESC_ENC(desc, MDST_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
516	DESC_ENC(desc, length_div_16, MDST_LENGTH_SHIFT, MDST_LENGTH_MASK);
517	DESC_ENC(desc, addr, MDST_ADDR_SHIFT, MDST_ADDR_MASK);
518
519	return desc;
520}
521
522static u64 flexrm_imm_desc(u64 data)
523{
524	u64 desc = 0;
525
526	DESC_ENC(desc, IMM_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
527	DESC_ENC(desc, data, IMM_DATA_SHIFT, IMM_DATA_MASK);
528
529	return desc;
530}
531
532static u64 flexrm_srct_desc(dma_addr_t addr, unsigned int length)
533{
534	u64 desc = 0;
535
536	DESC_ENC(desc, SRCT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
537	DESC_ENC(desc, length, SRCT_LENGTH_SHIFT, SRCT_LENGTH_MASK);
538	DESC_ENC(desc, addr, SRCT_ADDR_SHIFT, SRCT_ADDR_MASK);
539
540	return desc;
541}
542
543static u64 flexrm_dstt_desc(dma_addr_t addr, unsigned int length)
544{
545	u64 desc = 0;
546
547	DESC_ENC(desc, DSTT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
548	DESC_ENC(desc, length, DSTT_LENGTH_SHIFT, DSTT_LENGTH_MASK);
549	DESC_ENC(desc, addr, DSTT_ADDR_SHIFT, DSTT_ADDR_MASK);
550
551	return desc;
552}
553
554static u64 flexrm_immt_desc(u64 data)
555{
556	u64 desc = 0;
557
558	DESC_ENC(desc, IMMT_TYPE, DESC_TYPE_SHIFT, DESC_TYPE_MASK);
559	DESC_ENC(desc, data, IMMT_DATA_SHIFT, IMMT_DATA_MASK);
560
561	return desc;
562}
563
564static bool flexrm_spu_sanity_check(struct brcm_message *msg)
565{
566	struct scatterlist *sg;
567
568	if (!msg->spu.src || !msg->spu.dst)
569		return false;
570	for (sg = msg->spu.src; sg; sg = sg_next(sg)) {
571		if (sg->length & 0xf) {
572			if (sg->length > SRC_LENGTH_MASK)
573				return false;
574		} else {
575			if (sg->length > (MSRC_LENGTH_MASK * 16))
576				return false;
577		}
578	}
579	for (sg = msg->spu.dst; sg; sg = sg_next(sg)) {
580		if (sg->length & 0xf) {
581			if (sg->length > DST_LENGTH_MASK)
582				return false;
583		} else {
584			if (sg->length > (MDST_LENGTH_MASK * 16))
585				return false;
586		}
587	}
588
589	return true;
590}
591
592static u32 flexrm_spu_estimate_nonheader_desc_count(struct brcm_message *msg)
593{
594	u32 cnt = 0;
595	unsigned int dst_target = 0;
596	struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
597
598	while (src_sg || dst_sg) {
599		if (src_sg) {
600			cnt++;
601			dst_target = src_sg->length;
602			src_sg = sg_next(src_sg);
603		} else
604			dst_target = UINT_MAX;
605
606		while (dst_target && dst_sg) {
607			cnt++;
608			if (dst_sg->length < dst_target)
609				dst_target -= dst_sg->length;
610			else
611				dst_target = 0;
612			dst_sg = sg_next(dst_sg);
613		}
614	}
615
616	return cnt;
617}
618
619static int flexrm_spu_dma_map(struct device *dev, struct brcm_message *msg)
620{
621	int rc;
622
623	rc = dma_map_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
624			DMA_TO_DEVICE);
625	if (!rc)
626		return -EIO;
627
628	rc = dma_map_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
629			DMA_FROM_DEVICE);
630	if (!rc) {
631		dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
632			     DMA_TO_DEVICE);
633		return -EIO;
634	}
635
636	return 0;
637}
638
639static void flexrm_spu_dma_unmap(struct device *dev, struct brcm_message *msg)
640{
641	dma_unmap_sg(dev, msg->spu.dst, sg_nents(msg->spu.dst),
642		     DMA_FROM_DEVICE);
643	dma_unmap_sg(dev, msg->spu.src, sg_nents(msg->spu.src),
644		     DMA_TO_DEVICE);
645}
646
647static void *flexrm_spu_write_descs(struct brcm_message *msg, u32 nhcnt,
648				     u32 reqid, void *desc_ptr, u32 toggle,
649				     void *start_desc, void *end_desc)
650{
651	u64 d;
652	u32 nhpos = 0;
653	void *orig_desc_ptr = desc_ptr;
654	unsigned int dst_target = 0;
655	struct scatterlist *src_sg = msg->spu.src, *dst_sg = msg->spu.dst;
656
657	while (src_sg || dst_sg) {
658		if (src_sg) {
659			if (sg_dma_len(src_sg) & 0xf)
660				d = flexrm_src_desc(sg_dma_address(src_sg),
661						     sg_dma_len(src_sg));
662			else
663				d = flexrm_msrc_desc(sg_dma_address(src_sg),
664						      sg_dma_len(src_sg)/16);
665			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
666					     d, &desc_ptr, &toggle,
667					     start_desc, end_desc);
668			nhpos++;
669			dst_target = sg_dma_len(src_sg);
670			src_sg = sg_next(src_sg);
671		} else
672			dst_target = UINT_MAX;
673
674		while (dst_target && dst_sg) {
675			if (sg_dma_len(dst_sg) & 0xf)
676				d = flexrm_dst_desc(sg_dma_address(dst_sg),
677						     sg_dma_len(dst_sg));
678			else
679				d = flexrm_mdst_desc(sg_dma_address(dst_sg),
680						      sg_dma_len(dst_sg)/16);
681			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
682					     d, &desc_ptr, &toggle,
683					     start_desc, end_desc);
684			nhpos++;
685			if (sg_dma_len(dst_sg) < dst_target)
686				dst_target -= sg_dma_len(dst_sg);
687			else
688				dst_target = 0;
689			dst_sg = sg_next(dst_sg);
690		}
691	}
692
693	/* Null descriptor with invalid toggle bit */
694	flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
695
696	/* Ensure that descriptors have been written to memory */
697	wmb();
698
699	/* Flip toggle bit in header */
700	flexrm_flip_header_toggle(orig_desc_ptr);
701
702	return desc_ptr;
703}
704
705static bool flexrm_sba_sanity_check(struct brcm_message *msg)
706{
707	u32 i;
708
709	if (!msg->sba.cmds || !msg->sba.cmds_count)
710		return false;
711
712	for (i = 0; i < msg->sba.cmds_count; i++) {
713		if (((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
714		     (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C)) &&
715		    (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT))
716			return false;
717		if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) &&
718		    (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
719			return false;
720		if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C) &&
721		    (msg->sba.cmds[i].data_len > SRCT_LENGTH_MASK))
722			return false;
723		if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP) &&
724		    (msg->sba.cmds[i].resp_len > DSTT_LENGTH_MASK))
725			return false;
726		if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT) &&
727		    (msg->sba.cmds[i].data_len > DSTT_LENGTH_MASK))
728			return false;
729	}
730
731	return true;
732}
733
734static u32 flexrm_sba_estimate_nonheader_desc_count(struct brcm_message *msg)
735{
736	u32 i, cnt;
737
738	cnt = 0;
739	for (i = 0; i < msg->sba.cmds_count; i++) {
740		cnt++;
741
742		if ((msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_B) ||
743		    (msg->sba.cmds[i].flags & BRCM_SBA_CMD_TYPE_C))
744			cnt++;
745
746		if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_RESP)
747			cnt++;
748
749		if (msg->sba.cmds[i].flags & BRCM_SBA_CMD_HAS_OUTPUT)
750			cnt++;
751	}
752
753	return cnt;
754}
755
756static void *flexrm_sba_write_descs(struct brcm_message *msg, u32 nhcnt,
757				     u32 reqid, void *desc_ptr, u32 toggle,
758				     void *start_desc, void *end_desc)
759{
760	u64 d;
761	u32 i, nhpos = 0;
762	struct brcm_sba_command *c;
763	void *orig_desc_ptr = desc_ptr;
764
765	/* Convert SBA commands into descriptors */
766	for (i = 0; i < msg->sba.cmds_count; i++) {
767		c = &msg->sba.cmds[i];
768
769		if ((c->flags & BRCM_SBA_CMD_HAS_RESP) &&
770		    (c->flags & BRCM_SBA_CMD_HAS_OUTPUT)) {
771			/* Destination response descriptor */
772			d = flexrm_dst_desc(c->resp, c->resp_len);
773			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
774					     d, &desc_ptr, &toggle,
775					     start_desc, end_desc);
776			nhpos++;
777		} else if (c->flags & BRCM_SBA_CMD_HAS_RESP) {
778			/* Destination response with tlast descriptor */
779			d = flexrm_dstt_desc(c->resp, c->resp_len);
780			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
781					     d, &desc_ptr, &toggle,
782					     start_desc, end_desc);
783			nhpos++;
784		}
785
786		if (c->flags & BRCM_SBA_CMD_HAS_OUTPUT) {
787			/* Destination with tlast descriptor */
788			d = flexrm_dstt_desc(c->data, c->data_len);
789			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
790					     d, &desc_ptr, &toggle,
791					     start_desc, end_desc);
792			nhpos++;
793		}
794
795		if (c->flags & BRCM_SBA_CMD_TYPE_B) {
796			/* Command as immediate descriptor */
797			d = flexrm_imm_desc(c->cmd);
798			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
799					     d, &desc_ptr, &toggle,
800					     start_desc, end_desc);
801			nhpos++;
802		} else {
803			/* Command as immediate descriptor with tlast */
804			d = flexrm_immt_desc(c->cmd);
805			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
806					     d, &desc_ptr, &toggle,
807					     start_desc, end_desc);
808			nhpos++;
809		}
810
811		if ((c->flags & BRCM_SBA_CMD_TYPE_B) ||
812		    (c->flags & BRCM_SBA_CMD_TYPE_C)) {
813			/* Source with tlast descriptor */
814			d = flexrm_srct_desc(c->data, c->data_len);
815			flexrm_enqueue_desc(nhpos, nhcnt, reqid,
816					     d, &desc_ptr, &toggle,
817					     start_desc, end_desc);
818			nhpos++;
819		}
820	}
821
822	/* Null descriptor with invalid toggle bit */
823	flexrm_write_desc(desc_ptr, flexrm_null_desc(!toggle));
824
825	/* Ensure that descriptors have been written to memory */
826	wmb();
827
828	/* Flip toggle bit in header */
829	flexrm_flip_header_toggle(orig_desc_ptr);
830
831	return desc_ptr;
832}
833
834static bool flexrm_sanity_check(struct brcm_message *msg)
835{
836	if (!msg)
837		return false;
838
839	switch (msg->type) {
840	case BRCM_MESSAGE_SPU:
841		return flexrm_spu_sanity_check(msg);
842	case BRCM_MESSAGE_SBA:
843		return flexrm_sba_sanity_check(msg);
844	default:
845		return false;
846	};
847}
848
849static u32 flexrm_estimate_nonheader_desc_count(struct brcm_message *msg)
850{
851	if (!msg)
852		return 0;
853
854	switch (msg->type) {
855	case BRCM_MESSAGE_SPU:
856		return flexrm_spu_estimate_nonheader_desc_count(msg);
857	case BRCM_MESSAGE_SBA:
858		return flexrm_sba_estimate_nonheader_desc_count(msg);
859	default:
860		return 0;
861	};
862}
863
864static int flexrm_dma_map(struct device *dev, struct brcm_message *msg)
865{
866	if (!dev || !msg)
867		return -EINVAL;
868
869	switch (msg->type) {
870	case BRCM_MESSAGE_SPU:
871		return flexrm_spu_dma_map(dev, msg);
872	default:
873		break;
874	}
875
876	return 0;
877}
878
879static void flexrm_dma_unmap(struct device *dev, struct brcm_message *msg)
880{
881	if (!dev || !msg)
882		return;
883
884	switch (msg->type) {
885	case BRCM_MESSAGE_SPU:
886		flexrm_spu_dma_unmap(dev, msg);
887		break;
888	default:
889		break;
890	}
891}
892
893static void *flexrm_write_descs(struct brcm_message *msg, u32 nhcnt,
894				u32 reqid, void *desc_ptr, u32 toggle,
895				void *start_desc, void *end_desc)
896{
897	if (!msg || !desc_ptr || !start_desc || !end_desc)
898		return ERR_PTR(-ENOTSUPP);
899
900	if ((desc_ptr < start_desc) || (end_desc <= desc_ptr))
901		return ERR_PTR(-ERANGE);
902
903	switch (msg->type) {
904	case BRCM_MESSAGE_SPU:
905		return flexrm_spu_write_descs(msg, nhcnt, reqid,
906					       desc_ptr, toggle,
907					       start_desc, end_desc);
908	case BRCM_MESSAGE_SBA:
909		return flexrm_sba_write_descs(msg, nhcnt, reqid,
910					       desc_ptr, toggle,
911					       start_desc, end_desc);
912	default:
913		return ERR_PTR(-ENOTSUPP);
914	};
915}
916
917/* ====== FlexRM driver helper routines ===== */
918
919static void flexrm_write_config_in_seqfile(struct flexrm_mbox *mbox,
920					   struct seq_file *file)
921{
922	int i;
923	const char *state;
924	struct flexrm_ring *ring;
925
926	seq_printf(file, "%-5s %-9s %-18s %-10s %-18s %-10s\n",
927		   "Ring#", "State", "BD_Addr", "BD_Size",
928		   "Cmpl_Addr", "Cmpl_Size");
929
930	for (i = 0; i < mbox->num_rings; i++) {
931		ring = &mbox->rings[i];
932		if (readl(ring->regs + RING_CONTROL) &
933		    BIT(CONTROL_ACTIVE_SHIFT))
934			state = "active";
935		else
936			state = "inactive";
937		seq_printf(file,
938			   "%-5d %-9s 0x%016llx 0x%08x 0x%016llx 0x%08x\n",
939			   ring->num, state,
940			   (unsigned long long)ring->bd_dma_base,
941			   (u32)RING_BD_SIZE,
942			   (unsigned long long)ring->cmpl_dma_base,
943			   (u32)RING_CMPL_SIZE);
944	}
945}
946
947static void flexrm_write_stats_in_seqfile(struct flexrm_mbox *mbox,
948					  struct seq_file *file)
949{
950	int i;
951	u32 val, bd_read_offset;
952	struct flexrm_ring *ring;
953
954	seq_printf(file, "%-5s %-10s %-10s %-10s %-11s %-11s\n",
955		   "Ring#", "BD_Read", "BD_Write",
956		   "Cmpl_Read", "Submitted", "Completed");
957
958	for (i = 0; i < mbox->num_rings; i++) {
959		ring = &mbox->rings[i];
960		bd_read_offset = readl_relaxed(ring->regs + RING_BD_READ_PTR);
961		val = readl_relaxed(ring->regs + RING_BD_START_ADDR);
962		bd_read_offset *= RING_DESC_SIZE;
963		bd_read_offset += (u32)(BD_START_ADDR_DECODE(val) -
964					ring->bd_dma_base);
965		seq_printf(file, "%-5d 0x%08x 0x%08x 0x%08x %-11d %-11d\n",
966			   ring->num,
967			   (u32)bd_read_offset,
968			   (u32)ring->bd_write_offset,
969			   (u32)ring->cmpl_read_offset,
970			   (u32)atomic_read(&ring->msg_send_count),
971			   (u32)atomic_read(&ring->msg_cmpl_count));
972	}
973}
974
975static int flexrm_new_request(struct flexrm_ring *ring,
976				struct brcm_message *batch_msg,
977				struct brcm_message *msg)
978{
979	void *next;
980	unsigned long flags;
981	u32 val, count, nhcnt;
982	u32 read_offset, write_offset;
983	bool exit_cleanup = false;
984	int ret = 0, reqid;
985
986	/* Do sanity check on message */
987	if (!flexrm_sanity_check(msg))
988		return -EIO;
989	msg->error = 0;
990
991	/* If no requests possible then save data pointer and goto done. */
992	spin_lock_irqsave(&ring->lock, flags);
993	reqid = bitmap_find_free_region(ring->requests_bmap,
994					RING_MAX_REQ_COUNT, 0);
995	spin_unlock_irqrestore(&ring->lock, flags);
996	if (reqid < 0)
997		return -ENOSPC;
998	ring->requests[reqid] = msg;
999
1000	/* Do DMA mappings for the message */
1001	ret = flexrm_dma_map(ring->mbox->dev, msg);
1002	if (ret < 0) {
1003		ring->requests[reqid] = NULL;
1004		spin_lock_irqsave(&ring->lock, flags);
1005		bitmap_release_region(ring->requests_bmap, reqid, 0);
1006		spin_unlock_irqrestore(&ring->lock, flags);
1007		return ret;
1008	}
1009
1010	/* Determine current HW BD read offset */
1011	read_offset = readl_relaxed(ring->regs + RING_BD_READ_PTR);
1012	val = readl_relaxed(ring->regs + RING_BD_START_ADDR);
1013	read_offset *= RING_DESC_SIZE;
1014	read_offset += (u32)(BD_START_ADDR_DECODE(val) - ring->bd_dma_base);
1015
1016	/*
1017	 * Number required descriptors = number of non-header descriptors +
1018	 *				 number of header descriptors +
1019	 *				 1x null descriptor
1020	 */
1021	nhcnt = flexrm_estimate_nonheader_desc_count(msg);
1022	count = flexrm_estimate_header_desc_count(nhcnt) + nhcnt + 1;
1023
1024	/* Check for available descriptor space. */
1025	write_offset = ring->bd_write_offset;
1026	while (count) {
1027		if (!flexrm_is_next_table_desc(ring->bd_base + write_offset))
1028			count--;
1029		write_offset += RING_DESC_SIZE;
1030		if (write_offset == RING_BD_SIZE)
1031			write_offset = 0x0;
1032		if (write_offset == read_offset)
1033			break;
1034	}
1035	if (count) {
1036		ret = -ENOSPC;
1037		exit_cleanup = true;
1038		goto exit;
1039	}
1040
1041	/* Write descriptors to ring */
1042	next = flexrm_write_descs(msg, nhcnt, reqid,
1043			ring->bd_base + ring->bd_write_offset,
1044			RING_BD_TOGGLE_VALID(ring->bd_write_offset),
1045			ring->bd_base, ring->bd_base + RING_BD_SIZE);
1046	if (IS_ERR(next)) {
1047		ret = PTR_ERR(next);
1048		exit_cleanup = true;
1049		goto exit;
1050	}
1051
1052	/* Save ring BD write offset */
1053	ring->bd_write_offset = (unsigned long)(next - ring->bd_base);
1054
1055	/* Increment number of messages sent */
1056	atomic_inc_return(&ring->msg_send_count);
1057
1058exit:
1059	/* Update error status in message */
1060	msg->error = ret;
1061
1062	/* Cleanup if we failed */
1063	if (exit_cleanup) {
1064		flexrm_dma_unmap(ring->mbox->dev, msg);
1065		ring->requests[reqid] = NULL;
1066		spin_lock_irqsave(&ring->lock, flags);
1067		bitmap_release_region(ring->requests_bmap, reqid, 0);
1068		spin_unlock_irqrestore(&ring->lock, flags);
1069	}
1070
1071	return ret;
1072}
1073
1074static int flexrm_process_completions(struct flexrm_ring *ring)
1075{
1076	u64 desc;
1077	int err, count = 0;
1078	unsigned long flags;
1079	struct brcm_message *msg = NULL;
1080	u32 reqid, cmpl_read_offset, cmpl_write_offset;
1081	struct mbox_chan *chan = &ring->mbox->controller.chans[ring->num];
1082
1083	spin_lock_irqsave(&ring->lock, flags);
1084
1085	/*
1086	 * Get current completion read and write offset
1087	 *
1088	 * Note: We should read completion write pointer at least once
1089	 * after we get a MSI interrupt because HW maintains internal
1090	 * MSI status which will allow next MSI interrupt only after
1091	 * completion write pointer is read.
1092	 */
1093	cmpl_write_offset = readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
1094	cmpl_write_offset *= RING_DESC_SIZE;
1095	cmpl_read_offset = ring->cmpl_read_offset;
1096	ring->cmpl_read_offset = cmpl_write_offset;
1097
1098	spin_unlock_irqrestore(&ring->lock, flags);
1099
1100	/* For each completed request notify mailbox clients */
1101	reqid = 0;
1102	while (cmpl_read_offset != cmpl_write_offset) {
1103		/* Dequeue next completion descriptor */
1104		desc = *((u64 *)(ring->cmpl_base + cmpl_read_offset));
1105
1106		/* Next read offset */
1107		cmpl_read_offset += RING_DESC_SIZE;
1108		if (cmpl_read_offset == RING_CMPL_SIZE)
1109			cmpl_read_offset = 0;
1110
1111		/* Decode error from completion descriptor */
1112		err = flexrm_cmpl_desc_to_error(desc);
1113		if (err < 0) {
1114			dev_warn(ring->mbox->dev,
1115			"ring%d got completion desc=0x%lx with error %d\n",
1116			ring->num, (unsigned long)desc, err);
1117		}
1118
1119		/* Determine request id from completion descriptor */
1120		reqid = flexrm_cmpl_desc_to_reqid(desc);
1121
1122		/* Determine message pointer based on reqid */
1123		msg = ring->requests[reqid];
1124		if (!msg) {
1125			dev_warn(ring->mbox->dev,
1126			"ring%d null msg pointer for completion desc=0x%lx\n",
1127			ring->num, (unsigned long)desc);
1128			continue;
1129		}
1130
1131		/* Release reqid for recycling */
1132		ring->requests[reqid] = NULL;
1133		spin_lock_irqsave(&ring->lock, flags);
1134		bitmap_release_region(ring->requests_bmap, reqid, 0);
1135		spin_unlock_irqrestore(&ring->lock, flags);
1136
1137		/* Unmap DMA mappings */
1138		flexrm_dma_unmap(ring->mbox->dev, msg);
1139
1140		/* Give-back message to mailbox client */
1141		msg->error = err;
1142		mbox_chan_received_data(chan, msg);
1143
1144		/* Increment number of completions processed */
1145		atomic_inc_return(&ring->msg_cmpl_count);
1146		count++;
1147	}
1148
1149	return count;
1150}
1151
1152/* ====== FlexRM Debugfs callbacks ====== */
1153
1154static int flexrm_debugfs_conf_show(struct seq_file *file, void *offset)
1155{
1156	struct flexrm_mbox *mbox = dev_get_drvdata(file->private);
1157
1158	/* Write config in file */
1159	flexrm_write_config_in_seqfile(mbox, file);
1160
1161	return 0;
1162}
1163
1164static int flexrm_debugfs_stats_show(struct seq_file *file, void *offset)
1165{
1166	struct flexrm_mbox *mbox = dev_get_drvdata(file->private);
1167
1168	/* Write stats in file */
1169	flexrm_write_stats_in_seqfile(mbox, file);
1170
1171	return 0;
1172}
1173
1174/* ====== FlexRM interrupt handler ===== */
1175
1176static irqreturn_t flexrm_irq_event(int irq, void *dev_id)
1177{
1178	/* We only have MSI for completions so just wakeup IRQ thread */
1179	/* Ring related errors will be informed via completion descriptors */
1180
1181	return IRQ_WAKE_THREAD;
1182}
1183
1184static irqreturn_t flexrm_irq_thread(int irq, void *dev_id)
1185{
1186	flexrm_process_completions(dev_id);
1187
1188	return IRQ_HANDLED;
1189}
1190
1191/* ====== FlexRM mailbox callbacks ===== */
1192
1193static int flexrm_send_data(struct mbox_chan *chan, void *data)
1194{
1195	int i, rc;
1196	struct flexrm_ring *ring = chan->con_priv;
1197	struct brcm_message *msg = data;
1198
1199	if (msg->type == BRCM_MESSAGE_BATCH) {
1200		for (i = msg->batch.msgs_queued;
1201		     i < msg->batch.msgs_count; i++) {
1202			rc = flexrm_new_request(ring, msg,
1203						 &msg->batch.msgs[i]);
1204			if (rc) {
1205				msg->error = rc;
1206				return rc;
1207			}
1208			msg->batch.msgs_queued++;
1209		}
1210		return 0;
1211	}
1212
1213	return flexrm_new_request(ring, NULL, data);
1214}
1215
1216static bool flexrm_peek_data(struct mbox_chan *chan)
1217{
1218	int cnt = flexrm_process_completions(chan->con_priv);
1219
1220	return (cnt > 0) ? true : false;
1221}
1222
1223static int flexrm_startup(struct mbox_chan *chan)
1224{
1225	u64 d;
1226	u32 val, off;
1227	int ret = 0;
1228	dma_addr_t next_addr;
1229	struct flexrm_ring *ring = chan->con_priv;
1230
1231	/* Allocate BD memory */
1232	ring->bd_base = dma_pool_alloc(ring->mbox->bd_pool,
1233				       GFP_KERNEL, &ring->bd_dma_base);
1234	if (!ring->bd_base) {
1235		dev_err(ring->mbox->dev,
1236			"can't allocate BD memory for ring%d\n",
1237			ring->num);
1238		ret = -ENOMEM;
1239		goto fail;
1240	}
1241
1242	/* Configure next table pointer entries in BD memory */
1243	for (off = 0; off < RING_BD_SIZE; off += RING_DESC_SIZE) {
1244		next_addr = off + RING_DESC_SIZE;
1245		if (next_addr == RING_BD_SIZE)
1246			next_addr = 0;
1247		next_addr += ring->bd_dma_base;
1248		if (RING_BD_ALIGN_CHECK(next_addr))
1249			d = flexrm_next_table_desc(RING_BD_TOGGLE_VALID(off),
1250						    next_addr);
1251		else
1252			d = flexrm_null_desc(RING_BD_TOGGLE_INVALID(off));
1253		flexrm_write_desc(ring->bd_base + off, d);
1254	}
1255
1256	/* Allocate completion memory */
1257	ring->cmpl_base = dma_pool_zalloc(ring->mbox->cmpl_pool,
1258					 GFP_KERNEL, &ring->cmpl_dma_base);
1259	if (!ring->cmpl_base) {
1260		dev_err(ring->mbox->dev,
1261			"can't allocate completion memory for ring%d\n",
1262			ring->num);
1263		ret = -ENOMEM;
1264		goto fail_free_bd_memory;
1265	}
1266
1267	/* Request IRQ */
1268	if (ring->irq == UINT_MAX) {
1269		dev_err(ring->mbox->dev,
1270			"ring%d IRQ not available\n", ring->num);
1271		ret = -ENODEV;
1272		goto fail_free_cmpl_memory;
1273	}
1274	ret = request_threaded_irq(ring->irq,
1275				   flexrm_irq_event,
1276				   flexrm_irq_thread,
1277				   0, dev_name(ring->mbox->dev), ring);
1278	if (ret) {
1279		dev_err(ring->mbox->dev,
1280			"failed to request ring%d IRQ\n", ring->num);
1281		goto fail_free_cmpl_memory;
1282	}
1283	ring->irq_requested = true;
1284
1285	/* Set IRQ affinity hint */
1286	ring->irq_aff_hint = CPU_MASK_NONE;
1287	val = ring->mbox->num_rings;
1288	val = (num_online_cpus() < val) ? val / num_online_cpus() : 1;
1289	cpumask_set_cpu((ring->num / val) % num_online_cpus(),
1290			&ring->irq_aff_hint);
1291	ret = irq_update_affinity_hint(ring->irq, &ring->irq_aff_hint);
1292	if (ret) {
1293		dev_err(ring->mbox->dev,
1294			"failed to set IRQ affinity hint for ring%d\n",
1295			ring->num);
1296		goto fail_free_irq;
1297	}
1298
1299	/* Disable/inactivate ring */
1300	writel_relaxed(0x0, ring->regs + RING_CONTROL);
1301
1302	/* Program BD start address */
1303	val = BD_START_ADDR_VALUE(ring->bd_dma_base);
1304	writel_relaxed(val, ring->regs + RING_BD_START_ADDR);
1305
1306	/* BD write pointer will be same as HW write pointer */
1307	ring->bd_write_offset =
1308			readl_relaxed(ring->regs + RING_BD_WRITE_PTR);
1309	ring->bd_write_offset *= RING_DESC_SIZE;
1310
1311	/* Program completion start address */
1312	val = CMPL_START_ADDR_VALUE(ring->cmpl_dma_base);
1313	writel_relaxed(val, ring->regs + RING_CMPL_START_ADDR);
1314
1315	/* Completion read pointer will be same as HW write pointer */
1316	ring->cmpl_read_offset =
1317			readl_relaxed(ring->regs + RING_CMPL_WRITE_PTR);
1318	ring->cmpl_read_offset *= RING_DESC_SIZE;
1319
1320	/* Read ring Tx, Rx, and Outstanding counts to clear */
1321	readl_relaxed(ring->regs + RING_NUM_REQ_RECV_LS);
1322	readl_relaxed(ring->regs + RING_NUM_REQ_RECV_MS);
1323	readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_LS);
1324	readl_relaxed(ring->regs + RING_NUM_REQ_TRANS_MS);
1325	readl_relaxed(ring->regs + RING_NUM_REQ_OUTSTAND);
1326
1327	/* Configure RING_MSI_CONTROL */
1328	val = 0;
1329	val |= (ring->msi_timer_val << MSI_TIMER_VAL_SHIFT);
1330	val |= BIT(MSI_ENABLE_SHIFT);
1331	val |= (ring->msi_count_threshold & MSI_COUNT_MASK) << MSI_COUNT_SHIFT;
1332	writel_relaxed(val, ring->regs + RING_MSI_CONTROL);
1333
1334	/* Enable/activate ring */
1335	val = BIT(CONTROL_ACTIVE_SHIFT);
1336	writel_relaxed(val, ring->regs + RING_CONTROL);
1337
1338	/* Reset stats to zero */
1339	atomic_set(&ring->msg_send_count, 0);
1340	atomic_set(&ring->msg_cmpl_count, 0);
1341
1342	return 0;
1343
1344fail_free_irq:
1345	free_irq(ring->irq, ring);
1346	ring->irq_requested = false;
1347fail_free_cmpl_memory:
1348	dma_pool_free(ring->mbox->cmpl_pool,
1349		      ring->cmpl_base, ring->cmpl_dma_base);
1350	ring->cmpl_base = NULL;
1351fail_free_bd_memory:
1352	dma_pool_free(ring->mbox->bd_pool,
1353		      ring->bd_base, ring->bd_dma_base);
1354	ring->bd_base = NULL;
1355fail:
1356	return ret;
1357}
1358
1359static void flexrm_shutdown(struct mbox_chan *chan)
1360{
1361	u32 reqid;
1362	unsigned int timeout;
1363	struct brcm_message *msg;
1364	struct flexrm_ring *ring = chan->con_priv;
1365
1366	/* Disable/inactivate ring */
1367	writel_relaxed(0x0, ring->regs + RING_CONTROL);
1368
1369	/* Set ring flush state */
1370	timeout = 1000; /* timeout of 1s */
1371	writel_relaxed(BIT(CONTROL_FLUSH_SHIFT),
1372			ring->regs + RING_CONTROL);
1373	do {
1374		if (readl_relaxed(ring->regs + RING_FLUSH_DONE) &
1375		    FLUSH_DONE_MASK)
1376			break;
1377		mdelay(1);
1378	} while (--timeout);
1379	if (!timeout)
1380		dev_err(ring->mbox->dev,
1381			"setting ring%d flush state timedout\n", ring->num);
1382
1383	/* Clear ring flush state */
1384	timeout = 1000; /* timeout of 1s */
1385	writel_relaxed(0x0, ring->regs + RING_CONTROL);
1386	do {
1387		if (!(readl_relaxed(ring->regs + RING_FLUSH_DONE) &
1388		      FLUSH_DONE_MASK))
1389			break;
1390		mdelay(1);
1391	} while (--timeout);
1392	if (!timeout)
1393		dev_err(ring->mbox->dev,
1394			"clearing ring%d flush state timedout\n", ring->num);
1395
1396	/* Abort all in-flight requests */
1397	for (reqid = 0; reqid < RING_MAX_REQ_COUNT; reqid++) {
1398		msg = ring->requests[reqid];
1399		if (!msg)
1400			continue;
1401
1402		/* Release reqid for recycling */
1403		ring->requests[reqid] = NULL;
1404
1405		/* Unmap DMA mappings */
1406		flexrm_dma_unmap(ring->mbox->dev, msg);
1407
1408		/* Give-back message to mailbox client */
1409		msg->error = -EIO;
1410		mbox_chan_received_data(chan, msg);
1411	}
1412
1413	/* Clear requests bitmap */
1414	bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT);
1415
1416	/* Release IRQ */
1417	if (ring->irq_requested) {
1418		irq_update_affinity_hint(ring->irq, NULL);
1419		free_irq(ring->irq, ring);
1420		ring->irq_requested = false;
1421	}
1422
1423	/* Free-up completion descriptor ring */
1424	if (ring->cmpl_base) {
1425		dma_pool_free(ring->mbox->cmpl_pool,
1426			      ring->cmpl_base, ring->cmpl_dma_base);
1427		ring->cmpl_base = NULL;
1428	}
1429
1430	/* Free-up BD descriptor ring */
1431	if (ring->bd_base) {
1432		dma_pool_free(ring->mbox->bd_pool,
1433			      ring->bd_base, ring->bd_dma_base);
1434		ring->bd_base = NULL;
1435	}
1436}
1437
1438static const struct mbox_chan_ops flexrm_mbox_chan_ops = {
1439	.send_data	= flexrm_send_data,
1440	.startup	= flexrm_startup,
1441	.shutdown	= flexrm_shutdown,
1442	.peek_data	= flexrm_peek_data,
1443};
1444
1445static struct mbox_chan *flexrm_mbox_of_xlate(struct mbox_controller *cntlr,
1446					const struct of_phandle_args *pa)
1447{
1448	struct mbox_chan *chan;
1449	struct flexrm_ring *ring;
1450
1451	if (pa->args_count < 3)
1452		return ERR_PTR(-EINVAL);
1453
1454	if (pa->args[0] >= cntlr->num_chans)
1455		return ERR_PTR(-ENOENT);
1456
1457	if (pa->args[1] > MSI_COUNT_MASK)
1458		return ERR_PTR(-EINVAL);
1459
1460	if (pa->args[2] > MSI_TIMER_VAL_MASK)
1461		return ERR_PTR(-EINVAL);
1462
1463	chan = &cntlr->chans[pa->args[0]];
1464	ring = chan->con_priv;
1465	ring->msi_count_threshold = pa->args[1];
1466	ring->msi_timer_val = pa->args[2];
1467
1468	return chan;
1469}
1470
1471/* ====== FlexRM platform driver ===== */
1472
1473static void flexrm_mbox_msi_write(struct msi_desc *desc, struct msi_msg *msg)
1474{
1475	struct device *dev = msi_desc_to_dev(desc);
1476	struct flexrm_mbox *mbox = dev_get_drvdata(dev);
1477	struct flexrm_ring *ring = &mbox->rings[desc->msi_index];
1478
1479	/* Configure per-Ring MSI registers */
1480	writel_relaxed(msg->address_lo, ring->regs + RING_MSI_ADDR_LS);
1481	writel_relaxed(msg->address_hi, ring->regs + RING_MSI_ADDR_MS);
1482	writel_relaxed(msg->data, ring->regs + RING_MSI_DATA_VALUE);
1483}
1484
1485static int flexrm_mbox_probe(struct platform_device *pdev)
1486{
1487	int index, ret = 0;
1488	void __iomem *regs;
1489	void __iomem *regs_end;
1490	struct resource *iomem;
1491	struct flexrm_ring *ring;
1492	struct flexrm_mbox *mbox;
1493	struct device *dev = &pdev->dev;
1494
1495	/* Allocate driver mailbox struct */
1496	mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
1497	if (!mbox) {
1498		ret = -ENOMEM;
1499		goto fail;
1500	}
1501	mbox->dev = dev;
1502	platform_set_drvdata(pdev, mbox);
1503
1504	/* Get resource for registers and map registers of all rings */
1505	mbox->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &iomem);
1506	if (!iomem || (resource_size(iomem) < RING_REGS_SIZE)) {
1507		ret = -ENODEV;
1508		goto fail;
1509	} else if (IS_ERR(mbox->regs)) {
1510		ret = PTR_ERR(mbox->regs);
1511		goto fail;
1512	}
1513	regs_end = mbox->regs + resource_size(iomem);
1514
1515	/* Scan and count available rings */
1516	mbox->num_rings = 0;
1517	for (regs = mbox->regs; regs < regs_end; regs += RING_REGS_SIZE) {
1518		if (readl_relaxed(regs + RING_VER) == RING_VER_MAGIC)
1519			mbox->num_rings++;
1520	}
1521	if (!mbox->num_rings) {
1522		ret = -ENODEV;
1523		goto fail;
1524	}
1525
1526	/* Allocate driver ring structs */
1527	ring = devm_kcalloc(dev, mbox->num_rings, sizeof(*ring), GFP_KERNEL);
1528	if (!ring) {
1529		ret = -ENOMEM;
1530		goto fail;
1531	}
1532	mbox->rings = ring;
1533
1534	/* Initialize members of driver ring structs */
1535	regs = mbox->regs;
1536	for (index = 0; index < mbox->num_rings; index++) {
1537		ring = &mbox->rings[index];
1538		ring->num = index;
1539		ring->mbox = mbox;
1540		while ((regs < regs_end) &&
1541		       (readl_relaxed(regs + RING_VER) != RING_VER_MAGIC))
1542			regs += RING_REGS_SIZE;
1543		if (regs_end <= regs) {
1544			ret = -ENODEV;
1545			goto fail;
1546		}
1547		ring->regs = regs;
1548		regs += RING_REGS_SIZE;
1549		ring->irq = UINT_MAX;
1550		ring->irq_requested = false;
1551		ring->msi_timer_val = MSI_TIMER_VAL_MASK;
1552		ring->msi_count_threshold = 0x1;
1553		memset(ring->requests, 0, sizeof(ring->requests));
1554		ring->bd_base = NULL;
1555		ring->bd_dma_base = 0;
1556		ring->cmpl_base = NULL;
1557		ring->cmpl_dma_base = 0;
1558		atomic_set(&ring->msg_send_count, 0);
1559		atomic_set(&ring->msg_cmpl_count, 0);
1560		spin_lock_init(&ring->lock);
1561		bitmap_zero(ring->requests_bmap, RING_MAX_REQ_COUNT);
1562		ring->cmpl_read_offset = 0;
1563	}
1564
1565	/* FlexRM is capable of 40-bit physical addresses only */
1566	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(40));
1567	if (ret) {
1568		ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
1569		if (ret)
1570			goto fail;
1571	}
1572
1573	/* Create DMA pool for ring BD memory */
1574	mbox->bd_pool = dma_pool_create("bd", dev, RING_BD_SIZE,
1575					1 << RING_BD_ALIGN_ORDER, 0);
1576	if (!mbox->bd_pool) {
1577		ret = -ENOMEM;
1578		goto fail;
1579	}
1580
1581	/* Create DMA pool for ring completion memory */
1582	mbox->cmpl_pool = dma_pool_create("cmpl", dev, RING_CMPL_SIZE,
1583					  1 << RING_CMPL_ALIGN_ORDER, 0);
1584	if (!mbox->cmpl_pool) {
1585		ret = -ENOMEM;
1586		goto fail_destroy_bd_pool;
1587	}
1588
1589	/* Allocate platform MSIs for each ring */
1590	ret = platform_device_msi_init_and_alloc_irqs(dev, mbox->num_rings,
1591						      flexrm_mbox_msi_write);
1592	if (ret)
1593		goto fail_destroy_cmpl_pool;
1594
1595	/* Save alloced IRQ numbers for each ring */
1596	for (index = 0; index < mbox->num_rings; index++)
1597		mbox->rings[index].irq = msi_get_virq(dev, index);
1598
1599	/* Check availability of debugfs */
1600	if (!debugfs_initialized())
1601		goto skip_debugfs;
1602
1603	/* Create debugfs root entry */
1604	mbox->root = debugfs_create_dir(dev_name(mbox->dev), NULL);
1605
1606	/* Create debugfs config entry */
1607	debugfs_create_devm_seqfile(mbox->dev, "config", mbox->root,
1608				    flexrm_debugfs_conf_show);
1609
1610	/* Create debugfs stats entry */
1611	debugfs_create_devm_seqfile(mbox->dev, "stats", mbox->root,
1612				    flexrm_debugfs_stats_show);
1613
1614skip_debugfs:
1615
1616	/* Initialize mailbox controller */
1617	mbox->controller.txdone_irq = false;
1618	mbox->controller.txdone_poll = false;
1619	mbox->controller.ops = &flexrm_mbox_chan_ops;
1620	mbox->controller.dev = dev;
1621	mbox->controller.num_chans = mbox->num_rings;
1622	mbox->controller.of_xlate = flexrm_mbox_of_xlate;
1623	mbox->controller.chans = devm_kcalloc(dev, mbox->num_rings,
1624				sizeof(*mbox->controller.chans), GFP_KERNEL);
1625	if (!mbox->controller.chans) {
1626		ret = -ENOMEM;
1627		goto fail_free_debugfs_root;
1628	}
1629	for (index = 0; index < mbox->num_rings; index++)
1630		mbox->controller.chans[index].con_priv = &mbox->rings[index];
1631
1632	/* Register mailbox controller */
1633	ret = devm_mbox_controller_register(dev, &mbox->controller);
1634	if (ret)
1635		goto fail_free_debugfs_root;
1636
1637	dev_info(dev, "registered flexrm mailbox with %d channels\n",
1638			mbox->controller.num_chans);
1639
1640	return 0;
1641
1642fail_free_debugfs_root:
1643	debugfs_remove_recursive(mbox->root);
1644	platform_device_msi_free_irqs_all(dev);
1645fail_destroy_cmpl_pool:
1646	dma_pool_destroy(mbox->cmpl_pool);
1647fail_destroy_bd_pool:
1648	dma_pool_destroy(mbox->bd_pool);
1649fail:
1650	return ret;
1651}
1652
1653static void flexrm_mbox_remove(struct platform_device *pdev)
1654{
1655	struct device *dev = &pdev->dev;
1656	struct flexrm_mbox *mbox = platform_get_drvdata(pdev);
1657
1658	debugfs_remove_recursive(mbox->root);
1659
1660	platform_device_msi_free_irqs_all(dev);
1661
1662	dma_pool_destroy(mbox->cmpl_pool);
1663	dma_pool_destroy(mbox->bd_pool);
1664}
1665
1666static const struct of_device_id flexrm_mbox_of_match[] = {
1667	{ .compatible = "brcm,iproc-flexrm-mbox", },
1668	{},
1669};
1670MODULE_DEVICE_TABLE(of, flexrm_mbox_of_match);
1671
1672static struct platform_driver flexrm_mbox_driver = {
1673	.driver = {
1674		.name = "brcm-flexrm-mbox",
1675		.of_match_table = flexrm_mbox_of_match,
1676	},
1677	.probe		= flexrm_mbox_probe,
1678	.remove_new	= flexrm_mbox_remove,
1679};
1680module_platform_driver(flexrm_mbox_driver);
1681
1682MODULE_AUTHOR("Anup Patel <anup.patel@broadcom.com>");
1683MODULE_DESCRIPTION("Broadcom FlexRM mailbox driver");
1684MODULE_LICENSE("GPL v2");
1685