1 // SPDX-License-Identifier: GPL-2.0-only
3 * amdtp-motu.c - a part of driver for MOTU FireWire series
5 * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
8 #include <linux/slab.h>
12 #define CREATE_TRACE_POINTS
13 #include "amdtp-motu-trace.h"
15 #define CIP_FMT_MOTU 0x02
16 #define CIP_FMT_MOTU_TX_V3 0x22
17 #define MOTU_FDF_AM824 0x22
19 #define TICKS_PER_CYCLE 3072
20 #define CYCLES_PER_SECOND 8000
21 #define TICKS_PER_SECOND (TICKS_PER_CYCLE * CYCLES_PER_SECOND)
23 #define CIP_SPH_CYCLE_SHIFT 12
24 #define CIP_SPH_CYCLE_MASK 0x01fff000
25 #define CIP_SPH_OFFSET_MASK 0x00000fff
28 * Nominally 3125 bytes/second, but the MIDI port's clock might be
29 * 1% too slow, and the bus clock 100 ppm too fast.
31 #define MIDI_BYTES_PER_SECOND 3093
34 unsigned int pcm_chunks;
35 unsigned int pcm_byte_offset;
37 struct snd_rawmidi_substream *midi;
38 unsigned int midi_ports;
39 unsigned int midi_flag_offset;
40 unsigned int midi_byte_offset;
43 unsigned int midi_db_interval;
45 struct amdtp_motu_cache *cache;
48 int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
49 unsigned int midi_ports,
50 struct snd_motu_packet_format *formats)
52 struct amdtp_motu *p = s->protocol;
53 unsigned int pcm_chunks, data_chunks, data_block_quadlets;
57 if (amdtp_stream_running(s))
60 for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
61 if (snd_motu_clock_rates[i] == rate) {
66 if (i == ARRAY_SIZE(snd_motu_clock_rates))
69 // Each data block includes SPH in its head. Data chunks follow with
70 // 3 byte alignment. Padding follows with zero to conform to quadlet
72 pcm_chunks = formats->pcm_chunks[mode];
73 data_chunks = formats->msg_chunks + pcm_chunks;
74 data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
76 err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
80 p->pcm_chunks = pcm_chunks;
81 p->pcm_byte_offset = formats->pcm_byte_offset;
83 p->midi_ports = midi_ports;
84 p->midi_flag_offset = formats->midi_flag_offset;
85 p->midi_byte_offset = formats->midi_byte_offset;
88 p->midi_db_interval = rate / MIDI_BYTES_PER_SECOND;
93 static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
94 __be32 *buffer, unsigned int data_blocks,
95 unsigned int pcm_frames)
97 struct amdtp_motu *p = s->protocol;
98 unsigned int channels = p->pcm_chunks;
99 struct snd_pcm_runtime *runtime = pcm->runtime;
100 unsigned int pcm_buffer_pointer;
101 int remaining_frames;
106 pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
107 pcm_buffer_pointer %= runtime->buffer_size;
109 dst = (void *)runtime->dma_area +
110 frames_to_bytes(runtime, pcm_buffer_pointer);
111 remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
113 for (i = 0; i < data_blocks; ++i) {
114 byte = (u8 *)buffer + p->pcm_byte_offset;
116 for (c = 0; c < channels; ++c) {
117 *dst = (byte[0] << 24) |
123 buffer += s->data_block_quadlets;
124 if (--remaining_frames == 0)
125 dst = (void *)runtime->dma_area;
129 static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
130 __be32 *buffer, unsigned int data_blocks,
131 unsigned int pcm_frames)
133 struct amdtp_motu *p = s->protocol;
134 unsigned int channels = p->pcm_chunks;
135 struct snd_pcm_runtime *runtime = pcm->runtime;
136 unsigned int pcm_buffer_pointer;
137 int remaining_frames;
142 pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
143 pcm_buffer_pointer %= runtime->buffer_size;
145 src = (void *)runtime->dma_area +
146 frames_to_bytes(runtime, pcm_buffer_pointer);
147 remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
149 for (i = 0; i < data_blocks; ++i) {
150 byte = (u8 *)buffer + p->pcm_byte_offset;
152 for (c = 0; c < channels; ++c) {
153 byte[0] = (*src >> 24) & 0xff;
154 byte[1] = (*src >> 16) & 0xff;
155 byte[2] = (*src >> 8) & 0xff;
160 buffer += s->data_block_quadlets;
161 if (--remaining_frames == 0)
162 src = (void *)runtime->dma_area;
166 static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
167 unsigned int data_blocks)
169 struct amdtp_motu *p = s->protocol;
170 unsigned int channels, i, c;
173 channels = p->pcm_chunks;
175 for (i = 0; i < data_blocks; ++i) {
176 byte = (u8 *)buffer + p->pcm_byte_offset;
178 for (c = 0; c < channels; ++c) {
185 buffer += s->data_block_quadlets;
189 int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
190 struct snd_pcm_runtime *runtime)
194 /* TODO: how to set an constraint for exactly 24bit PCM sample? */
195 err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
199 return amdtp_stream_add_pcm_hw_constraints(s, runtime);
202 void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
203 struct snd_rawmidi_substream *midi)
205 struct amdtp_motu *p = s->protocol;
207 if (port < p->midi_ports)
208 WRITE_ONCE(p->midi, midi);
211 static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
212 unsigned int data_blocks)
214 struct amdtp_motu *p = s->protocol;
215 struct snd_rawmidi_substream *midi = READ_ONCE(p->midi);
219 for (i = 0; i < data_blocks; i++) {
222 if (midi && p->midi_db_count == 0 &&
223 snd_rawmidi_transmit(midi, b + p->midi_byte_offset, 1) == 1) {
224 b[p->midi_flag_offset] = 0x01;
226 b[p->midi_byte_offset] = 0x00;
227 b[p->midi_flag_offset] = 0x00;
230 buffer += s->data_block_quadlets;
232 if (--p->midi_db_count < 0)
233 p->midi_db_count = p->midi_db_interval;
237 static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
238 unsigned int data_blocks)
240 struct amdtp_motu *p = s->protocol;
241 struct snd_rawmidi_substream *midi;
245 for (i = 0; i < data_blocks; i++) {
247 midi = READ_ONCE(p->midi);
249 if (midi && (b[p->midi_flag_offset] & 0x01))
250 snd_rawmidi_receive(midi, b + p->midi_byte_offset, 1);
252 buffer += s->data_block_quadlets;
256 /* For tracepoints. */
257 static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
258 unsigned int data_blocks,
259 unsigned int data_block_quadlets)
263 for (i = 0; i < data_blocks; ++i) {
264 *frames = be32_to_cpu(*buffer);
265 buffer += data_block_quadlets;
270 /* For tracepoints. */
271 static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
272 unsigned int data_blocks,
273 unsigned int data_block_quadlets)
277 /* This is just for v2/v3 protocol. */
278 for (i = 0; i < data_blocks; ++i) {
279 *frames = be32_to_cpu(buffer[1]);
281 *frames |= be32_to_cpu(buffer[2]) >> 16;
283 buffer += data_block_quadlets;
287 static void probe_tracepoints_events(struct amdtp_stream *s,
288 const struct pkt_desc *descs,
289 unsigned int packets)
293 for (i = 0; i < packets; ++i) {
294 const struct pkt_desc *desc = descs + i;
295 __be32 *buf = desc->ctx_payload;
296 unsigned int data_blocks = desc->data_blocks;
298 trace_data_block_sph(s, data_blocks, buf);
299 trace_data_block_message(s, data_blocks, buf);
303 static void cache_event_offsets(struct amdtp_motu_cache *cache, const __be32 *buf,
304 unsigned int data_blocks, unsigned int data_block_quadlets)
306 unsigned int *event_offsets = cache->event_offsets;
307 const unsigned int cache_size = cache->size;
308 unsigned int cache_tail = cache->tail;
309 unsigned int base_tick = cache->tx_cycle_count * TICKS_PER_CYCLE;
312 for (i = 0; i < data_blocks; ++i) {
313 u32 sph = be32_to_cpu(*buf);
316 tick = ((sph & CIP_SPH_CYCLE_MASK) >> CIP_SPH_CYCLE_SHIFT) * TICKS_PER_CYCLE +
317 (sph & CIP_SPH_OFFSET_MASK);
319 if (tick < base_tick)
320 tick += TICKS_PER_SECOND;
321 event_offsets[cache_tail] = tick - base_tick;
323 cache_tail = (cache_tail + 1) % cache_size;
324 buf += data_block_quadlets;
327 cache->tail = cache_tail;
328 cache->tx_cycle_count = (cache->tx_cycle_count + 1) % CYCLES_PER_SECOND;
331 static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
332 const struct pkt_desc *descs,
333 unsigned int packets,
334 struct snd_pcm_substream *pcm)
336 struct amdtp_motu *p = s->protocol;
337 unsigned int pcm_frames = 0;
340 if (p->cache->tx_cycle_count == UINT_MAX)
341 p->cache->tx_cycle_count = (s->domain->processing_cycle.tx_start % CYCLES_PER_SECOND);
343 // For data block processing.
344 for (i = 0; i < packets; ++i) {
345 const struct pkt_desc *desc = descs + i;
346 __be32 *buf = desc->ctx_payload;
347 unsigned int data_blocks = desc->data_blocks;
349 cache_event_offsets(p->cache, buf, data_blocks, s->data_block_quadlets);
352 read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
353 pcm_frames += data_blocks;
357 read_midi_messages(s, buf, data_blocks);
361 if (trace_data_block_sph_enabled() ||
362 trace_data_block_message_enabled())
363 probe_tracepoints_events(s, descs, packets);
368 static void write_sph(struct amdtp_motu_cache *cache, __be32 *buffer, unsigned int data_blocks,
369 unsigned int data_block_quadlets)
371 unsigned int *event_offsets = cache->event_offsets;
372 const unsigned int cache_size = cache->size;
373 unsigned int cache_head = cache->head;
374 unsigned int base_tick = cache->rx_cycle_count * TICKS_PER_CYCLE;
377 for (i = 0; i < data_blocks; i++) {
378 unsigned int tick = (base_tick + event_offsets[cache_head]) % TICKS_PER_SECOND;
379 u32 sph = ((tick / TICKS_PER_CYCLE) << CIP_SPH_CYCLE_SHIFT) | (tick % TICKS_PER_CYCLE);
380 *buffer = cpu_to_be32(sph);
382 cache_head = (cache_head + 1) % cache_size;
383 buffer += data_block_quadlets;
386 cache->head = cache_head;
387 cache->rx_cycle_count = (cache->rx_cycle_count + 1) % CYCLES_PER_SECOND;
390 static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
391 const struct pkt_desc *descs,
392 unsigned int packets,
393 struct snd_pcm_substream *pcm)
395 struct amdtp_motu *p = s->protocol;
396 unsigned int pcm_frames = 0;
399 if (p->cache->rx_cycle_count == UINT_MAX)
400 p->cache->rx_cycle_count = (s->domain->processing_cycle.rx_start % CYCLES_PER_SECOND);
402 // For data block processing.
403 for (i = 0; i < packets; ++i) {
404 const struct pkt_desc *desc = descs + i;
405 __be32 *buf = desc->ctx_payload;
406 unsigned int data_blocks = desc->data_blocks;
409 write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
410 pcm_frames += data_blocks;
412 write_pcm_silence(s, buf, data_blocks);
416 write_midi_messages(s, buf, data_blocks);
418 // TODO: how to interact control messages between userspace?
420 write_sph(p->cache, buf, data_blocks, s->data_block_quadlets);
424 if (trace_data_block_sph_enabled() ||
425 trace_data_block_message_enabled())
426 probe_tracepoints_events(s, descs, packets);
431 int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
432 enum amdtp_stream_direction dir,
433 const struct snd_motu_spec *spec, struct amdtp_motu_cache *cache)
435 amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
436 int fmt = CIP_FMT_MOTU;
437 unsigned int flags = CIP_BLOCKING | CIP_UNAWARE_SYT;
438 struct amdtp_motu *p;
441 if (dir == AMDTP_IN_STREAM) {
442 process_ctx_payloads = process_ir_ctx_payloads;
445 * Units of version 3 transmits packets with invalid CIP header
446 * against IEC 61883-1.
448 if (spec->protocol_version == SND_MOTU_PROTOCOL_V3) {
449 flags |= CIP_WRONG_DBS |
450 CIP_SKIP_DBC_ZERO_CHECK |
451 CIP_HEADER_WITHOUT_EOH;
452 fmt = CIP_FMT_MOTU_TX_V3;
455 if (spec == &snd_motu_spec_8pre ||
456 spec == &snd_motu_spec_ultralite) {
457 // 8pre has some quirks.
458 flags |= CIP_WRONG_DBS |
459 CIP_SKIP_DBC_ZERO_CHECK;
462 process_ctx_payloads = process_it_ctx_payloads;
463 flags |= CIP_DBC_IS_END_EVENT;
466 err = amdtp_stream_init(s, unit, dir, flags, fmt, process_ctx_payloads,
467 sizeof(struct amdtp_motu));
473 if (dir == AMDTP_OUT_STREAM) {
474 // Use fixed value for FDF field.
475 s->ctx_data.rx.fdf = MOTU_FDF_AM824;