1 /*
2 * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #ifndef _HARDWARE_DMA_H_
8 #define _HARDWARE_DMA_H_
9
10 #include "pico.h"
11 #include "hardware/structs/dma.h"
12 #include "hardware/regs/dreq.h"
13 #include "pico/assert.h"
14
15 #ifdef __cplusplus
16 extern "C" {
17 #endif
18
19 /** \file hardware/dma.h
20 * \defgroup hardware_dma hardware_dma
21 *
22 * DMA Controller API
23 *
24 * The RP2040 Direct Memory Access (DMA) master performs bulk data transfers on a processor’s
25 * behalf. This leaves processors free to attend to other tasks, or enter low-power sleep states. The
26 * data throughput of the DMA is also significantly higher than one of RP2040’s processors.
27 *
28 * The DMA can perform one read access and one write access, up to 32 bits in size, every clock cycle.
29 * There are 12 independent channels, which each supervise a sequence of bus transfers, usually in
30 * one of the following scenarios:
31 *
32 * * Memory to peripheral
33 * * Peripheral to memory
34 * * Memory to memory
35 */
36
37 // this is not defined in generated dreq.h
38 #define DREQ_FORCE 63
39
40 // PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_DMA, Enable/disable DMA assertions, type=bool, default=0, group=hardware_dma
41 #ifndef PARAM_ASSERTIONS_ENABLED_DMA
42 #define PARAM_ASSERTIONS_ENABLED_DMA 0
43 #endif
44
check_dma_channel_param(uint channel)45 static inline void check_dma_channel_param(uint channel) {
46 #if PARAM_ASSERTIONS_ENABLED(DMA)
47 // this method is used a lot by inline functions so avoid code bloat by deferring to function
48 extern void check_dma_channel_param_impl(uint channel);
49 check_dma_channel_param_impl(channel);
50 #endif
51 }
52
dma_channel_hw_addr(uint channel)53 inline static dma_channel_hw_t *dma_channel_hw_addr(uint channel) {
54 check_dma_channel_param(channel);
55 return &dma_hw->ch[channel];
56 }
57
58 /*! \brief Mark a dma channel as used
59 * \ingroup hardware_dma
60 *
61 * Method for cooperative claiming of hardware. Will cause a panic if the channel
62 * is already claimed. Use of this method by libraries detects accidental
63 * configurations that would fail in unpredictable ways.
64 *
65 * \param channel the dma channel
66 */
67 void dma_channel_claim(uint channel);
68
69 /*! \brief Mark multiple dma channels as used
70 * \ingroup hardware_dma
71 *
72 * Method for cooperative claiming of hardware. Will cause a panic if any of the channels
73 * are already claimed. Use of this method by libraries detects accidental
74 * configurations that would fail in unpredictable ways.
75 *
76 * \param channel_mask Bitfield of all required channels to claim (bit 0 == channel 0, bit 1 == channel 1 etc)
77 */
78 void dma_claim_mask(uint32_t channel_mask);
79
80 /*! \brief Mark a dma channel as no longer used
81 * \ingroup hardware_dma
82 *
83 * Method for cooperative claiming of hardware.
84 *
85 * \param channel the dma channel to release
86 */
87 void dma_channel_unclaim(uint channel);
88
89 /*! \brief Claim a free dma channel
90 * \ingroup hardware_dma
91 *
92 * \param required if true the function will panic if none are available
93 * \return the dma channel number or -1 if required was false, and none were free
94 */
95 int dma_claim_unused_channel(bool required);
96
97 /** \brief DMA channel configuration
98 * \defgroup channel_config channel_config
99 * \ingroup hardware_dma
100 *
101 * A DMA channel needs to be configured, these functions provide handy helpers to set up configuration
102 * structures. See \ref dma_channel_config
103 *
104 */
105
106 /*! \brief Enumeration of available DMA channel transfer sizes.
107 * \ingroup hardware_dma
108 *
109 * Names indicate the number of bits.
110 */
111 enum dma_channel_transfer_size {
112 DMA_SIZE_8 = 0, ///< Byte transfer (8 bits)
113 DMA_SIZE_16 = 1, ///< Half word transfer (16 bits)
114 DMA_SIZE_32 = 2 ///< Word transfer (32 bits)
115 };
116
117 typedef struct {
118 uint32_t ctrl;
119 } dma_channel_config;
120
121 /*! \brief Set DMA channel read increment
122 * \ingroup channel_config
123 *
124 * \param c Pointer to channel configuration data
125 * \param incr True to enable read address increments, if false, each read will be from the same address
126 * Usually disabled for peripheral to memory transfers
127 */
channel_config_set_read_increment(dma_channel_config * c,bool incr)128 static inline void channel_config_set_read_increment(dma_channel_config *c, bool incr) {
129 c->ctrl = incr ? (c->ctrl | DMA_CH0_CTRL_TRIG_INCR_READ_BITS) : (c->ctrl & ~DMA_CH0_CTRL_TRIG_INCR_READ_BITS);
130 }
131
132 /*! \brief Set DMA channel write increment
133 * \ingroup channel_config
134 *
135 * \param c Pointer to channel configuration data
136 * \param incr True to enable write address increments, if false, each write will be to the same address
137 * Usually disabled for memory to peripheral transfers
138 * Usually disabled for memory to peripheral transfers
139 */
channel_config_set_write_increment(dma_channel_config * c,bool incr)140 static inline void channel_config_set_write_increment(dma_channel_config *c, bool incr) {
141 c->ctrl = incr ? (c->ctrl | DMA_CH0_CTRL_TRIG_INCR_WRITE_BITS) : (c->ctrl & ~DMA_CH0_CTRL_TRIG_INCR_WRITE_BITS);
142 }
143
144 /*! \brief Select a transfer request signal
145 * \ingroup channel_config
146 *
147 * The channel uses the transfer request signal to pace its data transfer rate.
148 * Sources for TREQ signals are internal (TIMERS) or external (DREQ, a Data Request from the system).
149 * 0x0 to 0x3a -> select DREQ n as TREQ
150 * 0x3b -> Select Timer 0 as TREQ
151 * 0x3c -> Select Timer 1 as TREQ
152 * 0x3d -> Select Timer 2 as TREQ (Optional)
153 * 0x3e -> Select Timer 3 as TREQ (Optional)
154 * 0x3f -> Permanent request, for unpaced transfers.
155 *
156 * \param c Pointer to channel configuration data
157 * \param dreq Source (see description)
158 */
channel_config_set_dreq(dma_channel_config * c,uint dreq)159 static inline void channel_config_set_dreq(dma_channel_config *c, uint dreq) {
160 assert(dreq <= DREQ_FORCE);
161 c->ctrl = (c->ctrl & ~DMA_CH0_CTRL_TRIG_TREQ_SEL_BITS) | (dreq << DMA_CH0_CTRL_TRIG_TREQ_SEL_LSB);
162 }
163
164 /*! \brief Set DMA channel completion channel
165 * \ingroup channel_config
166 *
167 * When this channel completes, it will trigger the channel indicated by chain_to. Disable by
168 * setting chain_to to itself (the same channel)
169 *
170 * \param c Pointer to channel configuration data
171 * \param chain_to Channel to trigger when this channel completes.
172 */
channel_config_set_chain_to(dma_channel_config * c,uint chain_to)173 static inline void channel_config_set_chain_to(dma_channel_config *c, uint chain_to) {
174 assert(chain_to <= NUM_DMA_CHANNELS);
175 c->ctrl = (c->ctrl & ~DMA_CH0_CTRL_TRIG_CHAIN_TO_BITS) | (chain_to << DMA_CH0_CTRL_TRIG_CHAIN_TO_LSB);
176 }
177
178 /*! \brief Set the size of each DMA bus transfer
179 * \ingroup channel_config
180 *
181 * Set the size of each bus transfer (byte/halfword/word). The read and write addresses
182 * advance by the specific amount (1/2/4 bytes) with each transfer.
183 *
184 * \param c Pointer to channel configuration data
185 * \param size See enum for possible values.
186 */
channel_config_set_transfer_data_size(dma_channel_config * c,enum dma_channel_transfer_size size)187 static inline void channel_config_set_transfer_data_size(dma_channel_config *c, enum dma_channel_transfer_size size) {
188 assert(size == DMA_SIZE_8 || size == DMA_SIZE_16 || size == DMA_SIZE_32);
189 c->ctrl = (c->ctrl & ~DMA_CH0_CTRL_TRIG_DATA_SIZE_BITS) | (size << DMA_CH0_CTRL_TRIG_DATA_SIZE_LSB);
190 }
191
192 /*! \brief Set address wrapping parameters
193 * \ingroup channel_config
194 *
195 * Size of address wrap region. If 0, don’t wrap. For values n > 0, only the lower n bits of the address
196 * will change. This wraps the address on a (1 << n) byte boundary, facilitating access to naturally-aligned
197 * ring buffers.
198 * Ring sizes between 2 and 32768 bytes are possible (size_bits from 1 - 15)
199 *
200 * 0x0 -> No wrapping.
201 *
202 * \param c Pointer to channel configuration data
203 * \param write True to apply to write addresses, false to apply to read addresses
204 * \param size_bits 0 to disable wrapping. Otherwise the size in bits of the changing part of the address.
205 * Effectively wraps the address on a (1 << size_bits) byte boundary.
206 */
channel_config_set_ring(dma_channel_config * c,bool write,uint size_bits)207 static inline void channel_config_set_ring(dma_channel_config *c, bool write, uint size_bits) {
208 assert(size_bits < 32);
209 c->ctrl = (c->ctrl & ~(DMA_CH0_CTRL_TRIG_RING_SIZE_BITS | DMA_CH0_CTRL_TRIG_RING_SEL_BITS)) |
210 (size_bits << DMA_CH0_CTRL_TRIG_RING_SIZE_LSB) |
211 (write ? DMA_CH0_CTRL_TRIG_RING_SEL_BITS : 0);
212 }
213
214 /*! \brief Set DMA byte swapping
215 * \ingroup channel_config
216 *
217 * No effect for byte data, for halfword data, the two bytes of each halfword are
218 * swapped. For word data, the four bytes of each word are swapped to reverse their order.
219 *
220 * \param c Pointer to channel configuration data
221 * \param bswap True to enable byte swapping
222 */
channel_config_set_bswap(dma_channel_config * c,bool bswap)223 static inline void channel_config_set_bswap(dma_channel_config *c, bool bswap) {
224 c->ctrl = bswap ? (c->ctrl | DMA_CH0_CTRL_TRIG_BSWAP_BITS) : (c->ctrl & ~DMA_CH0_CTRL_TRIG_BSWAP_BITS);
225 }
226
227 /*! \brief Set IRQ quiet mode
228 * \ingroup channel_config
229 *
230 * In QUIET mode, the channel does not generate IRQs at the end of every transfer block. Instead,
231 * an IRQ is raised when NULL is written to a trigger register, indicating the end of a control
232 * block chain.
233 *
234 * \param c Pointer to channel configuration data
235 * \param irq_quiet True to enable quiet mode, false to disable.
236 */
channel_config_set_irq_quiet(dma_channel_config * c,bool irq_quiet)237 static inline void channel_config_set_irq_quiet(dma_channel_config *c, bool irq_quiet) {
238 c->ctrl = irq_quiet ? (c->ctrl | DMA_CH0_CTRL_TRIG_IRQ_QUIET_BITS) : (c->ctrl & ~DMA_CH0_CTRL_TRIG_IRQ_QUIET_BITS);
239 }
240
241 /*!
242 * \brief Enable/Disable the DMA channel
243 * \ingroup channel_config
244 *
245 * When false, the channel will ignore triggers, stop issuing transfers, and pause the current transfer sequence (i.e. BUSY will
246 * remain high if already high)
247 *
248 * \param c Pointer to channel configuration data
249 * \param enable True to enable the DMA channel. When enabled, the channel will respond to triggering events, and start transferring data.
250 *
251 */
channel_config_set_enable(dma_channel_config * c,bool enable)252 static inline void channel_config_set_enable(dma_channel_config *c, bool enable) {
253 c->ctrl = enable ? (c->ctrl | DMA_CH0_CTRL_TRIG_EN_BITS) : (c->ctrl & ~DMA_CH0_CTRL_TRIG_EN_BITS);
254 }
255
256 /*! \brief Enable access to channel by sniff hardware.
257 * \ingroup channel_config
258 *
259 * Sniff HW must be enabled and have this channel selected.
260 *
261 * \param c Pointer to channel configuration data
262 * \param sniff_enable True to enable the Sniff HW access to this DMA channel.
263 */
channel_config_set_sniff_enable(dma_channel_config * c,bool sniff_enable)264 static inline void channel_config_set_sniff_enable(dma_channel_config *c, bool sniff_enable) {
265 c->ctrl = sniff_enable ? (c->ctrl | DMA_CH0_CTRL_TRIG_SNIFF_EN_BITS) : (c->ctrl &
266 ~DMA_CH0_CTRL_TRIG_SNIFF_EN_BITS);
267 }
268
269 /*! \brief Get the default channel configuration for a given channel
270 * \ingroup channel_config
271 *
272 * Setting | Default
273 * --------|--------
274 * Read Increment | true
275 * Write Increment | false
276 * DReq | DREQ_FORCE
277 * Chain to | self
278 * Data size | DMA_SIZE_32
279 * Ring | write=false, size=0 (i.e. off)
280 * Byte Swap | false
281 * Quiet IRQs | false
282 * Channel Enable | true
283 * Sniff Enable | false
284 *
285 * \param channel DMA channel
286 * \return the default configuration which can then be modified.
287 */
dma_channel_get_default_config(uint channel)288 static inline dma_channel_config dma_channel_get_default_config(uint channel) {
289 dma_channel_config c = {0};
290 channel_config_set_read_increment(&c, true);
291 channel_config_set_write_increment(&c, false);
292 channel_config_set_dreq(&c, DREQ_FORCE);
293 channel_config_set_chain_to(&c, channel);
294 channel_config_set_transfer_data_size(&c, DMA_SIZE_32);
295 channel_config_set_ring(&c, false, 0);
296 channel_config_set_bswap(&c, false);
297 channel_config_set_irq_quiet(&c, false);
298 channel_config_set_enable(&c, true);
299 channel_config_set_sniff_enable(&c, false);
300 return c;
301 }
302
303 /*! \brief Get the current configuration for the specified channel.
304 * \ingroup channel_config
305 *
306 * \param channel DMA channel
307 * \return The current configuration as read from the HW register (not cached)
308 */
dma_get_channel_config(uint channel)309 static inline dma_channel_config dma_get_channel_config(uint channel) {
310 dma_channel_config c;
311 c.ctrl = dma_channel_hw_addr(channel)->ctrl_trig;
312 return c;
313 }
314
315 /*! \brief Get the raw configuration register from a channel configuration
316 * \ingroup channel_config
317 *
318 * \param config Pointer to a config structure.
319 * \return Register content
320 */
channel_config_get_ctrl_value(const dma_channel_config * config)321 static inline uint32_t channel_config_get_ctrl_value(const dma_channel_config *config) {
322 return config->ctrl;
323 }
324
325 /*! \brief Set a channel configuration
326 * \ingroup hardware_dma
327 *
328 * \param channel DMA channel
329 * \param config Pointer to a config structure with required configuration
330 * \param trigger True to trigger the transfer immediately
331 */
dma_channel_set_config(uint channel,const dma_channel_config * config,bool trigger)332 static inline void dma_channel_set_config(uint channel, const dma_channel_config *config, bool trigger) {
333 // Don't use CTRL_TRIG since we don't want to start a transfer
334 if (!trigger) {
335 dma_channel_hw_addr(channel)->al1_ctrl = channel_config_get_ctrl_value(config);
336 } else {
337 dma_channel_hw_addr(channel)->ctrl_trig = channel_config_get_ctrl_value(config);
338 }
339 }
340
341 /*! \brief Set the DMA initial read address.
342 * \ingroup hardware_dma
343 *
344 * \param channel DMA channel
345 * \param read_addr Initial read address of transfer.
346 * \param trigger True to start the transfer immediately
347 */
dma_channel_set_read_addr(uint channel,const volatile void * read_addr,bool trigger)348 static inline void dma_channel_set_read_addr(uint channel, const volatile void *read_addr, bool trigger) {
349 if (!trigger) {
350 dma_channel_hw_addr(channel)->read_addr = (uintptr_t) read_addr;
351 } else {
352 dma_channel_hw_addr(channel)->al3_read_addr_trig = (uintptr_t) read_addr;
353 }
354 }
355
356 /*! \brief Set the DMA initial read address
357 * \ingroup hardware_dma
358 *
359 * \param channel DMA channel
360 * \param write_addr Initial write address of transfer.
361 * \param trigger True to start the transfer immediately
362 */
dma_channel_set_write_addr(uint channel,volatile void * write_addr,bool trigger)363 static inline void dma_channel_set_write_addr(uint channel, volatile void *write_addr, bool trigger) {
364 if (!trigger) {
365 dma_channel_hw_addr(channel)->write_addr = (uintptr_t) write_addr;
366 } else {
367 dma_channel_hw_addr(channel)->al2_write_addr_trig = (uintptr_t) write_addr;
368 }
369 }
370
371 /*! \brief Set the number of bus transfers the channel will do
372 * \ingroup hardware_dma
373 *
374 * \param channel DMA channel
375 * \param trans_count The number of transfers (not NOT bytes, see channel_config_set_transfer_data_size)
376 * \param trigger True to start the transfer immediately
377 */
dma_channel_set_trans_count(uint channel,uint32_t trans_count,bool trigger)378 static inline void dma_channel_set_trans_count(uint channel, uint32_t trans_count, bool trigger) {
379 if (!trigger) {
380 dma_channel_hw_addr(channel)->transfer_count = trans_count;
381 } else {
382 dma_channel_hw_addr(channel)->al1_transfer_count_trig = trans_count;
383 }
384 }
385
386 /*! \brief Configure all DMA parameters and optionally start transfer
387 * \ingroup hardware_dma
388 *
389 * \param channel DMA channel
390 * \param config Pointer to DMA config structure
391 * \param write_addr Initial write address
392 * \param read_addr Initial read address
393 * \param transfer_count Number of transfers to perform
394 * \param trigger True to start the transfer immediately
395 */
dma_channel_configure(uint channel,const dma_channel_config * config,volatile void * write_addr,const volatile void * read_addr,uint transfer_count,bool trigger)396 static inline void dma_channel_configure(uint channel, const dma_channel_config *config, volatile void *write_addr,
397 const volatile void *read_addr,
398 uint transfer_count, bool trigger) {
399 dma_channel_set_read_addr(channel, read_addr, false);
400 dma_channel_set_write_addr(channel, write_addr, false);
401 dma_channel_set_trans_count(channel, transfer_count, false);
402 dma_channel_set_config(channel, config, trigger);
403 }
404
405 /*! \brief Start a DMA transfer from a buffer immediately
406 * \ingroup hardware_dma
407 *
408 * \param channel DMA channel
409 * \param read_addr Sets the initial read address
410 * \param transfer_count Number of transfers to make. Not bytes, but the number of transfers of channel_config_set_transfer_data_size() to be sent.
411 */
dma_channel_transfer_from_buffer_now(uint channel,void * read_addr,uint32_t transfer_count)412 inline static void __attribute__((always_inline)) dma_channel_transfer_from_buffer_now(uint channel, void *read_addr,
413 uint32_t transfer_count) {
414 // check_dma_channel_param(channel);
415 dma_channel_hw_t *hw = dma_channel_hw_addr(channel);
416 hw->read_addr = (uintptr_t) read_addr;
417 hw->al1_transfer_count_trig = transfer_count;
418 }
419
420 /*! \brief Start a DMA transfer to a buffer immediately
421 * \ingroup hardware_dma
422 *
423 * \param channel DMA channel
424 * \param write_addr Sets the initial write address
425 * \param transfer_count Number of transfers to make. Not bytes, but the number of transfers of channel_config_set_transfer_data_size() to be sent.
426 */
dma_channel_transfer_to_buffer_now(uint channel,void * write_addr,uint32_t transfer_count)427 inline static void dma_channel_transfer_to_buffer_now(uint channel, void *write_addr, uint32_t transfer_count) {
428 dma_channel_hw_t *hw = dma_channel_hw_addr(channel);
429 hw->write_addr = (uintptr_t) write_addr;
430 hw->al1_transfer_count_trig = transfer_count;
431 }
432
433 /*! \brief Start one or more channels simultaneously
434 * \ingroup hardware_dma
435 *
436 * \param chan_mask Bitmask of all the channels requiring starting. Channel 0 = bit 0, channel 1 = bit 1 etc.
437 */
dma_start_channel_mask(uint32_t chan_mask)438 static inline void dma_start_channel_mask(uint32_t chan_mask) {
439 valid_params_if(DMA, chan_mask && chan_mask < (1u << NUM_DMA_CHANNELS));
440 dma_hw->multi_channel_trigger = chan_mask;
441 }
442
443 /*! \brief Start a single DMA channel
444 * \ingroup hardware_dma
445 *
446 * \param channel DMA channel
447 */
dma_channel_start(uint channel)448 static inline void dma_channel_start(uint channel) {
449 dma_start_channel_mask(1u << channel);
450 }
451
452 /*! \brief Stop a DMA transfer
453 * \ingroup hardware_dma
454 *
455 * Function will only return once the DMA has stopped.
456 *
457 * \param channel DMA channel
458 */
dma_channel_abort(uint channel)459 static inline void dma_channel_abort(uint channel) {
460 check_dma_channel_param(channel);
461 dma_hw->abort = 1u << channel;
462 // Bit will go 0 once channel has reached safe state
463 // (i.e. any in-flight transfers have retired)
464 while (dma_hw->abort & (1ul << channel)) tight_loop_contents();
465 }
466
467 /*! \brief Enable single DMA channel interrupt 0
468 * \ingroup hardware_dma
469 *
470 * \param channel DMA channel
471 * \param enabled true to enable interrupt 0 on specified channel, false to disable.
472 */
dma_channel_set_irq0_enabled(uint channel,bool enabled)473 static inline void dma_channel_set_irq0_enabled(uint channel, bool enabled) {
474 check_dma_channel_param(channel);
475 check_hw_layout(dma_hw_t, inte0, DMA_INTE0_OFFSET);
476 if (enabled)
477 hw_set_bits(&dma_hw->inte0, 1u << channel);
478 else
479 hw_clear_bits(&dma_hw->inte0, 1u << channel);
480 }
481
482 /*! \brief Enable multiple DMA channels interrupt 0
483 * \ingroup hardware_dma
484 *
485 * \param channel_mask Bitmask of all the channels to enable/disable. Channel 0 = bit 0, channel 1 = bit 1 etc.
486 * \param enabled true to enable all the interrupts specified in the mask, false to disable all the interrupts specified in the mask.
487 */
dma_set_irq0_channel_mask_enabled(uint32_t channel_mask,bool enabled)488 static inline void dma_set_irq0_channel_mask_enabled(uint32_t channel_mask, bool enabled) {
489 if (enabled) {
490 hw_set_bits(&dma_hw->inte0, channel_mask);
491 } else {
492 hw_clear_bits(&dma_hw->inte0, channel_mask);
493 }
494 }
495
496 /*! \brief Enable single DMA channel interrupt 1
497 * \ingroup hardware_dma
498 *
499 * \param channel DMA channel
500 * \param enabled true to enable interrupt 1 on specified channel, false to disable.
501 */
dma_channel_set_irq1_enabled(uint channel,bool enabled)502 static inline void dma_channel_set_irq1_enabled(uint channel, bool enabled) {
503 check_dma_channel_param(channel);
504 check_hw_layout(dma_hw_t, inte1, DMA_INTE1_OFFSET);
505 if (enabled)
506 hw_set_bits(&dma_hw->inte1, 1u << channel);
507 else
508 hw_clear_bits(&dma_hw->inte1, 1u << channel);
509 }
510
511 /*! \brief Enable multiple DMA channels interrupt 0
512 * \ingroup hardware_dma
513 *
514 * \param channel_mask Bitmask of all the channels to enable/disable. Channel 0 = bit 0, channel 1 = bit 1 etc.
515 * \param enabled true to enable all the interrupts specified in the mask, false to disable all the interrupts specified in the mask.
516 */
dma_set_irq1_channel_mask_enabled(uint32_t channel_mask,bool enabled)517 static inline void dma_set_irq1_channel_mask_enabled(uint32_t channel_mask, bool enabled) {
518 if (enabled) {
519 hw_set_bits(&dma_hw->inte1, channel_mask);
520 } else {
521 hw_clear_bits(&dma_hw->inte1, channel_mask);
522 }
523 }
524
525 /*! \brief Check if DMA channel is busy
526 * \ingroup hardware_dma
527 *
528 * \param channel DMA channel
529 * \return true if the channel is currently busy
530 */
dma_channel_is_busy(uint channel)531 inline static bool dma_channel_is_busy(uint channel) {
532 check_dma_channel_param(channel);
533 return !!(dma_hw->ch[channel].al1_ctrl & DMA_CH0_CTRL_TRIG_BUSY_BITS);
534 }
535
536 /*! \brief Wait for a DMA channel transfer to complete
537 * \ingroup hardware_dma
538 *
539 * \param channel DMA channel
540 */
dma_channel_wait_for_finish_blocking(uint channel)541 inline static void dma_channel_wait_for_finish_blocking(uint channel) {
542 while (dma_channel_is_busy(channel)) tight_loop_contents();
543 }
544
545 /*! \brief Enable the DMA sniffing targeting the specified channel
546 * \ingroup hardware_dma
547 *
548 * The mode can be one of the following:
549 *
550 * Mode | Function
551 * -----|---------
552 * 0x0 | Calculate a CRC-32 (IEEE802.3 polynomial)
553 * 0x1 | Calculate a CRC-32 (IEEE802.3 polynomial) with bit reversed data
554 * 0x2 | Calculate a CRC-16-CCITT
555 * 0x3 | Calculate a CRC-16-CCITT with bit reversed data
556 * 0xe | XOR reduction over all data. == 1 if the total 1 population count is odd.
557 * 0xf | Calculate a simple 32-bit checksum (addition with a 32 bit accumulator)
558 *
559 * \param channel DMA channel
560 * \param mode See description
561 * \param force_channel_enable Set true to also turn on sniffing in the channel configuration (this
562 * is usually what you want, but sometimes you might have a chain DMA with only certain segments
563 * of the chain sniffed, in which case you might pass false).
564 */
dma_sniffer_enable(uint channel,uint mode,bool force_channel_enable)565 inline static void dma_sniffer_enable(uint channel, uint mode, bool force_channel_enable) {
566 check_dma_channel_param(channel);
567 check_hw_layout(dma_hw_t, sniff_ctrl, DMA_SNIFF_CTRL_OFFSET);
568 if (force_channel_enable) {
569 hw_set_bits(&dma_hw->ch[channel].al1_ctrl, DMA_CH0_CTRL_TRIG_SNIFF_EN_BITS);
570 }
571 dma_hw->sniff_ctrl = ((channel << DMA_SNIFF_CTRL_DMACH_LSB) & DMA_SNIFF_CTRL_DMACH_BITS) |
572 ((mode << DMA_SNIFF_CTRL_CALC_LSB) & DMA_SNIFF_CTRL_CALC_BITS) |
573 DMA_SNIFF_CTRL_EN_BITS;
574 }
575
576 /*! \brief Enable the Sniffer byte swap function
577 * \ingroup hardware_dma
578 *
579 * Locally perform a byte reverse on the sniffed data, before feeding into checksum.
580 *
581 * Note that the sniff hardware is downstream of the DMA channel byteswap performed in the
582 * read master: if channel_config_set_bswap() and dma_sniffer_set_byte_swap_enabled() are both enabled,
583 * their effects cancel from the sniffer’s point of view.
584 *
585 * \param swap Set true to enable byte swapping
586 */
dma_sniffer_set_byte_swap_enabled(bool swap)587 inline static void dma_sniffer_set_byte_swap_enabled(bool swap) {
588 if (swap)
589 hw_set_bits(&dma_hw->sniff_ctrl, DMA_SNIFF_CTRL_BSWAP_BITS);
590 else
591 hw_clear_bits(&dma_hw->sniff_ctrl, DMA_SNIFF_CTRL_BSWAP_BITS);
592 }
593
594 /*! \brief Disable the DMA sniffer
595 * \ingroup hardware_dma
596 *
597 */
dma_sniffer_disable(void)598 inline static void dma_sniffer_disable(void) {
599 dma_hw->sniff_ctrl = 0;
600 }
601
602 #ifndef NDEBUG
603 void print_dma_ctrl(dma_channel_hw_t *channel);
604 #endif
605
606 #ifdef __cplusplus
607 }
608 #endif
609
610 #endif
611