at_hdmac_regs.h 16 KB

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  1. /* SPDX-License-Identifier: GPL-2.0-or-later */
  2. /*
  3. * Header file for the Atmel AHB DMA Controller driver
  4. *
  5. * Copyright (C) 2008 Atmel Corporation
  6. */
  7. #ifndef AT_HDMAC_REGS_H
  8. #define AT_HDMAC_REGS_H
  9. #define AT_DMA_MAX_NR_CHANNELS 8
  10. #define AT_DMA_GCFG 0x00 /* Global Configuration Register */
  11. #define AT_DMA_IF_BIGEND(i) (0x1 << (i)) /* AHB-Lite Interface i in Big-endian mode */
  12. #define AT_DMA_ARB_CFG (0x1 << 4) /* Arbiter mode. */
  13. #define AT_DMA_ARB_CFG_FIXED (0x0 << 4)
  14. #define AT_DMA_ARB_CFG_ROUND_ROBIN (0x1 << 4)
  15. #define AT_DMA_EN 0x04 /* Controller Enable Register */
  16. #define AT_DMA_ENABLE (0x1 << 0)
  17. #define AT_DMA_SREQ 0x08 /* Software Single Request Register */
  18. #define AT_DMA_SSREQ(x) (0x1 << ((x) << 1)) /* Request a source single transfer on channel x */
  19. #define AT_DMA_DSREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination single transfer on channel x */
  20. #define AT_DMA_CREQ 0x0C /* Software Chunk Transfer Request Register */
  21. #define AT_DMA_SCREQ(x) (0x1 << ((x) << 1)) /* Request a source chunk transfer on channel x */
  22. #define AT_DMA_DCREQ(x) (0x1 << (1 + ((x) << 1))) /* Request a destination chunk transfer on channel x */
  23. #define AT_DMA_LAST 0x10 /* Software Last Transfer Flag Register */
  24. #define AT_DMA_SLAST(x) (0x1 << ((x) << 1)) /* This src rq is last tx of buffer on channel x */
  25. #define AT_DMA_DLAST(x) (0x1 << (1 + ((x) << 1))) /* This dst rq is last tx of buffer on channel x */
  26. #define AT_DMA_SYNC 0x14 /* Request Synchronization Register */
  27. #define AT_DMA_SYR(h) (0x1 << (h)) /* Synchronize handshake line h */
  28. /* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
  29. #define AT_DMA_EBCIER 0x18 /* Enable register */
  30. #define AT_DMA_EBCIDR 0x1C /* Disable register */
  31. #define AT_DMA_EBCIMR 0x20 /* Mask Register */
  32. #define AT_DMA_EBCISR 0x24 /* Status Register */
  33. #define AT_DMA_CBTC_OFFSET 8
  34. #define AT_DMA_ERR_OFFSET 16
  35. #define AT_DMA_BTC(x) (0x1 << (x))
  36. #define AT_DMA_CBTC(x) (0x1 << (AT_DMA_CBTC_OFFSET + (x)))
  37. #define AT_DMA_ERR(x) (0x1 << (AT_DMA_ERR_OFFSET + (x)))
  38. #define AT_DMA_CHER 0x28 /* Channel Handler Enable Register */
  39. #define AT_DMA_ENA(x) (0x1 << (x))
  40. #define AT_DMA_SUSP(x) (0x1 << ( 8 + (x)))
  41. #define AT_DMA_KEEP(x) (0x1 << (24 + (x)))
  42. #define AT_DMA_CHDR 0x2C /* Channel Handler Disable Register */
  43. #define AT_DMA_DIS(x) (0x1 << (x))
  44. #define AT_DMA_RES(x) (0x1 << ( 8 + (x)))
  45. #define AT_DMA_CHSR 0x30 /* Channel Handler Status Register */
  46. #define AT_DMA_EMPT(x) (0x1 << (16 + (x)))
  47. #define AT_DMA_STAL(x) (0x1 << (24 + (x)))
  48. #define AT_DMA_CH_REGS_BASE 0x3C /* Channel registers base address */
  49. #define ch_regs(x) (AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
  50. /* Hardware register offset for each channel */
  51. #define ATC_SADDR_OFFSET 0x00 /* Source Address Register */
  52. #define ATC_DADDR_OFFSET 0x04 /* Destination Address Register */
  53. #define ATC_DSCR_OFFSET 0x08 /* Descriptor Address Register */
  54. #define ATC_CTRLA_OFFSET 0x0C /* Control A Register */
  55. #define ATC_CTRLB_OFFSET 0x10 /* Control B Register */
  56. #define ATC_CFG_OFFSET 0x14 /* Configuration Register */
  57. #define ATC_SPIP_OFFSET 0x18 /* Src PIP Configuration Register */
  58. #define ATC_DPIP_OFFSET 0x1C /* Dst PIP Configuration Register */
  59. /* Bitfield definitions */
  60. /* Bitfields in DSCR */
  61. #define ATC_DSCR_IF(i) (0x3 & (i)) /* Dsc feched via AHB-Lite Interface i */
  62. /* Bitfields in CTRLA */
  63. #define ATC_BTSIZE_MAX 0xFFFFUL /* Maximum Buffer Transfer Size */
  64. #define ATC_BTSIZE(x) (ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
  65. #define ATC_SCSIZE_MASK (0x7 << 16) /* Source Chunk Transfer Size */
  66. #define ATC_SCSIZE(x) (ATC_SCSIZE_MASK & ((x) << 16))
  67. #define ATC_SCSIZE_1 (0x0 << 16)
  68. #define ATC_SCSIZE_4 (0x1 << 16)
  69. #define ATC_SCSIZE_8 (0x2 << 16)
  70. #define ATC_SCSIZE_16 (0x3 << 16)
  71. #define ATC_SCSIZE_32 (0x4 << 16)
  72. #define ATC_SCSIZE_64 (0x5 << 16)
  73. #define ATC_SCSIZE_128 (0x6 << 16)
  74. #define ATC_SCSIZE_256 (0x7 << 16)
  75. #define ATC_DCSIZE_MASK (0x7 << 20) /* Destination Chunk Transfer Size */
  76. #define ATC_DCSIZE(x) (ATC_DCSIZE_MASK & ((x) << 20))
  77. #define ATC_DCSIZE_1 (0x0 << 20)
  78. #define ATC_DCSIZE_4 (0x1 << 20)
  79. #define ATC_DCSIZE_8 (0x2 << 20)
  80. #define ATC_DCSIZE_16 (0x3 << 20)
  81. #define ATC_DCSIZE_32 (0x4 << 20)
  82. #define ATC_DCSIZE_64 (0x5 << 20)
  83. #define ATC_DCSIZE_128 (0x6 << 20)
  84. #define ATC_DCSIZE_256 (0x7 << 20)
  85. #define ATC_SRC_WIDTH_MASK (0x3 << 24) /* Source Single Transfer Size */
  86. #define ATC_SRC_WIDTH(x) ((x) << 24)
  87. #define ATC_SRC_WIDTH_BYTE (0x0 << 24)
  88. #define ATC_SRC_WIDTH_HALFWORD (0x1 << 24)
  89. #define ATC_SRC_WIDTH_WORD (0x2 << 24)
  90. #define ATC_REG_TO_SRC_WIDTH(r) (((r) >> 24) & 0x3)
  91. #define ATC_DST_WIDTH_MASK (0x3 << 28) /* Destination Single Transfer Size */
  92. #define ATC_DST_WIDTH(x) ((x) << 28)
  93. #define ATC_DST_WIDTH_BYTE (0x0 << 28)
  94. #define ATC_DST_WIDTH_HALFWORD (0x1 << 28)
  95. #define ATC_DST_WIDTH_WORD (0x2 << 28)
  96. #define ATC_DONE (0x1 << 31) /* Tx Done (only written back in descriptor) */
  97. /* Bitfields in CTRLB */
  98. #define ATC_SIF(i) (0x3 & (i)) /* Src tx done via AHB-Lite Interface i */
  99. #define ATC_DIF(i) ((0x3 & (i)) << 4) /* Dst tx done via AHB-Lite Interface i */
  100. /* Specify AHB interfaces */
  101. #define AT_DMA_MEM_IF 0 /* interface 0 as memory interface */
  102. #define AT_DMA_PER_IF 1 /* interface 1 as peripheral interface */
  103. #define ATC_SRC_PIP (0x1 << 8) /* Source Picture-in-Picture enabled */
  104. #define ATC_DST_PIP (0x1 << 12) /* Destination Picture-in-Picture enabled */
  105. #define ATC_SRC_DSCR_DIS (0x1 << 16) /* Src Descriptor fetch disable */
  106. #define ATC_DST_DSCR_DIS (0x1 << 20) /* Dst Descriptor fetch disable */
  107. #define ATC_FC_MASK (0x7 << 21) /* Choose Flow Controller */
  108. #define ATC_FC_MEM2MEM (0x0 << 21) /* Mem-to-Mem (DMA) */
  109. #define ATC_FC_MEM2PER (0x1 << 21) /* Mem-to-Periph (DMA) */
  110. #define ATC_FC_PER2MEM (0x2 << 21) /* Periph-to-Mem (DMA) */
  111. #define ATC_FC_PER2PER (0x3 << 21) /* Periph-to-Periph (DMA) */
  112. #define ATC_FC_PER2MEM_PER (0x4 << 21) /* Periph-to-Mem (Peripheral) */
  113. #define ATC_FC_MEM2PER_PER (0x5 << 21) /* Mem-to-Periph (Peripheral) */
  114. #define ATC_FC_PER2PER_SRCPER (0x6 << 21) /* Periph-to-Periph (Src Peripheral) */
  115. #define ATC_FC_PER2PER_DSTPER (0x7 << 21) /* Periph-to-Periph (Dst Peripheral) */
  116. #define ATC_SRC_ADDR_MODE_MASK (0x3 << 24)
  117. #define ATC_SRC_ADDR_MODE_INCR (0x0 << 24) /* Incrementing Mode */
  118. #define ATC_SRC_ADDR_MODE_DECR (0x1 << 24) /* Decrementing Mode */
  119. #define ATC_SRC_ADDR_MODE_FIXED (0x2 << 24) /* Fixed Mode */
  120. #define ATC_DST_ADDR_MODE_MASK (0x3 << 28)
  121. #define ATC_DST_ADDR_MODE_INCR (0x0 << 28) /* Incrementing Mode */
  122. #define ATC_DST_ADDR_MODE_DECR (0x1 << 28) /* Decrementing Mode */
  123. #define ATC_DST_ADDR_MODE_FIXED (0x2 << 28) /* Fixed Mode */
  124. #define ATC_IEN (0x1 << 30) /* BTC interrupt enable (active low) */
  125. #define ATC_AUTO (0x1 << 31) /* Auto multiple buffer tx enable */
  126. /* Bitfields in CFG */
  127. #define ATC_PER_MSB(h) ((0x30U & (h)) >> 4) /* Extract most significant bits of a handshaking identifier */
  128. #define ATC_SRC_PER(h) (0xFU & (h)) /* Channel src rq associated with periph handshaking ifc h */
  129. #define ATC_DST_PER(h) ((0xFU & (h)) << 4) /* Channel dst rq associated with periph handshaking ifc h */
  130. #define ATC_SRC_REP (0x1 << 8) /* Source Replay Mod */
  131. #define ATC_SRC_H2SEL (0x1 << 9) /* Source Handshaking Mod */
  132. #define ATC_SRC_H2SEL_SW (0x0 << 9)
  133. #define ATC_SRC_H2SEL_HW (0x1 << 9)
  134. #define ATC_SRC_PER_MSB(h) (ATC_PER_MSB(h) << 10) /* Channel src rq (most significant bits) */
  135. #define ATC_DST_REP (0x1 << 12) /* Destination Replay Mod */
  136. #define ATC_DST_H2SEL (0x1 << 13) /* Destination Handshaking Mod */
  137. #define ATC_DST_H2SEL_SW (0x0 << 13)
  138. #define ATC_DST_H2SEL_HW (0x1 << 13)
  139. #define ATC_DST_PER_MSB(h) (ATC_PER_MSB(h) << 14) /* Channel dst rq (most significant bits) */
  140. #define ATC_SOD (0x1 << 16) /* Stop On Done */
  141. #define ATC_LOCK_IF (0x1 << 20) /* Interface Lock */
  142. #define ATC_LOCK_B (0x1 << 21) /* AHB Bus Lock */
  143. #define ATC_LOCK_IF_L (0x1 << 22) /* Master Interface Arbiter Lock */
  144. #define ATC_LOCK_IF_L_CHUNK (0x0 << 22)
  145. #define ATC_LOCK_IF_L_BUFFER (0x1 << 22)
  146. #define ATC_AHB_PROT_MASK (0x7 << 24) /* AHB Protection */
  147. #define ATC_FIFOCFG_MASK (0x3 << 28) /* FIFO Request Configuration */
  148. #define ATC_FIFOCFG_LARGESTBURST (0x0 << 28)
  149. #define ATC_FIFOCFG_HALFFIFO (0x1 << 28)
  150. #define ATC_FIFOCFG_ENOUGHSPACE (0x2 << 28)
  151. /* Bitfields in SPIP */
  152. #define ATC_SPIP_HOLE(x) (0xFFFFU & (x))
  153. #define ATC_SPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
  154. /* Bitfields in DPIP */
  155. #define ATC_DPIP_HOLE(x) (0xFFFFU & (x))
  156. #define ATC_DPIP_BOUNDARY(x) ((0x3FF & (x)) << 16)
  157. /*-- descriptors -----------------------------------------------------*/
  158. /* LLI == Linked List Item; aka DMA buffer descriptor */
  159. struct at_lli {
  160. /* values that are not changed by hardware */
  161. u32 saddr;
  162. u32 daddr;
  163. /* value that may get written back: */
  164. u32 ctrla;
  165. /* more values that are not changed by hardware */
  166. u32 ctrlb;
  167. u32 dscr; /* chain to next lli */
  168. };
  169. /**
  170. * struct at_desc - software descriptor
  171. * @at_lli: hardware lli structure
  172. * @txd: support for the async_tx api
  173. * @desc_node: node on the channed descriptors list
  174. * @len: descriptor byte count
  175. * @total_len: total transaction byte count
  176. */
  177. struct at_desc {
  178. /* FIRST values the hardware uses */
  179. struct at_lli lli;
  180. /* THEN values for driver housekeeping */
  181. struct list_head tx_list;
  182. struct dma_async_tx_descriptor txd;
  183. struct list_head desc_node;
  184. size_t len;
  185. size_t total_len;
  186. /* Interleaved data */
  187. size_t boundary;
  188. size_t dst_hole;
  189. size_t src_hole;
  190. /* Memset temporary buffer */
  191. bool memset_buffer;
  192. dma_addr_t memset_paddr;
  193. int *memset_vaddr;
  194. };
  195. static inline struct at_desc *
  196. txd_to_at_desc(struct dma_async_tx_descriptor *txd)
  197. {
  198. return container_of(txd, struct at_desc, txd);
  199. }
  200. /*-- Channels --------------------------------------------------------*/
  201. /**
  202. * atc_status - information bits stored in channel status flag
  203. *
  204. * Manipulated with atomic operations.
  205. */
  206. enum atc_status {
  207. ATC_IS_ERROR = 0,
  208. ATC_IS_PAUSED = 1,
  209. ATC_IS_CYCLIC = 24,
  210. };
  211. /**
  212. * struct at_dma_chan - internal representation of an Atmel HDMAC channel
  213. * @chan_common: common dmaengine channel object members
  214. * @device: parent device
  215. * @ch_regs: memory mapped register base
  216. * @mask: channel index in a mask
  217. * @per_if: peripheral interface
  218. * @mem_if: memory interface
  219. * @status: transmit status information from irq/prep* functions
  220. * to tasklet (use atomic operations)
  221. * @tasklet: bottom half to finish transaction work
  222. * @save_cfg: configuration register that is saved on suspend/resume cycle
  223. * @save_dscr: for cyclic operations, preserve next descriptor address in
  224. * the cyclic list on suspend/resume cycle
  225. * @dma_sconfig: configuration for slave transfers, passed via
  226. * .device_config
  227. * @lock: serializes enqueue/dequeue operations to descriptors lists
  228. * @active_list: list of descriptors dmaengine is being running on
  229. * @queue: list of descriptors ready to be submitted to engine
  230. * @free_list: list of descriptors usable by the channel
  231. */
  232. struct at_dma_chan {
  233. struct dma_chan chan_common;
  234. struct at_dma *device;
  235. void __iomem *ch_regs;
  236. u8 mask;
  237. u8 per_if;
  238. u8 mem_if;
  239. unsigned long status;
  240. struct tasklet_struct tasklet;
  241. u32 save_cfg;
  242. u32 save_dscr;
  243. struct dma_slave_config dma_sconfig;
  244. spinlock_t lock;
  245. /* these other elements are all protected by lock */
  246. struct list_head active_list;
  247. struct list_head queue;
  248. struct list_head free_list;
  249. };
  250. #define channel_readl(atchan, name) \
  251. __raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
  252. #define channel_writel(atchan, name, val) \
  253. __raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
  254. static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
  255. {
  256. return container_of(dchan, struct at_dma_chan, chan_common);
  257. }
  258. /*
  259. * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
  260. * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
  261. *
  262. * This can be done by finding most significant bit set.
  263. */
  264. static inline void convert_burst(u32 *maxburst)
  265. {
  266. if (*maxburst > 1)
  267. *maxburst = fls(*maxburst) - 2;
  268. else
  269. *maxburst = 0;
  270. }
  271. /*
  272. * Fix sconfig's bus width according to at_hdmac.
  273. * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
  274. */
  275. static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
  276. {
  277. switch (addr_width) {
  278. case DMA_SLAVE_BUSWIDTH_2_BYTES:
  279. return 1;
  280. case DMA_SLAVE_BUSWIDTH_4_BYTES:
  281. return 2;
  282. default:
  283. /* For 1 byte width or fallback */
  284. return 0;
  285. }
  286. }
  287. /*-- Controller ------------------------------------------------------*/
  288. /**
  289. * struct at_dma - internal representation of an Atmel HDMA Controller
  290. * @chan_common: common dmaengine dma_device object members
  291. * @atdma_devtype: identifier of DMA controller compatibility
  292. * @ch_regs: memory mapped register base
  293. * @clk: dma controller clock
  294. * @save_imr: interrupt mask register that is saved on suspend/resume cycle
  295. * @all_chan_mask: all channels availlable in a mask
  296. * @dma_desc_pool: base of DMA descriptor region (DMA address)
  297. * @chan: channels table to store at_dma_chan structures
  298. */
  299. struct at_dma {
  300. struct dma_device dma_common;
  301. void __iomem *regs;
  302. struct clk *clk;
  303. u32 save_imr;
  304. u8 all_chan_mask;
  305. struct dma_pool *dma_desc_pool;
  306. struct dma_pool *memset_pool;
  307. /* AT THE END channels table */
  308. struct at_dma_chan chan[];
  309. };
  310. #define dma_readl(atdma, name) \
  311. __raw_readl((atdma)->regs + AT_DMA_##name)
  312. #define dma_writel(atdma, name, val) \
  313. __raw_writel((val), (atdma)->regs + AT_DMA_##name)
  314. static inline struct at_dma *to_at_dma(struct dma_device *ddev)
  315. {
  316. return container_of(ddev, struct at_dma, dma_common);
  317. }
  318. /*-- Helper functions ------------------------------------------------*/
  319. static struct device *chan2dev(struct dma_chan *chan)
  320. {
  321. return &chan->dev->device;
  322. }
  323. #if defined(VERBOSE_DEBUG)
  324. static void vdbg_dump_regs(struct at_dma_chan *atchan)
  325. {
  326. struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
  327. dev_err(chan2dev(&atchan->chan_common),
  328. " channel %d : imr = 0x%x, chsr = 0x%x\n",
  329. atchan->chan_common.chan_id,
  330. dma_readl(atdma, EBCIMR),
  331. dma_readl(atdma, CHSR));
  332. dev_err(chan2dev(&atchan->chan_common),
  333. " channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
  334. channel_readl(atchan, SADDR),
  335. channel_readl(atchan, DADDR),
  336. channel_readl(atchan, CTRLA),
  337. channel_readl(atchan, CTRLB),
  338. channel_readl(atchan, CFG),
  339. channel_readl(atchan, DSCR));
  340. }
  341. #else
  342. static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
  343. #endif
  344. static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
  345. {
  346. dev_crit(chan2dev(&atchan->chan_common),
  347. "desc: s%pad d%pad ctrl0x%x:0x%x l%pad\n",
  348. &lli->saddr, &lli->daddr,
  349. lli->ctrla, lli->ctrlb, &lli->dscr);
  350. }
  351. static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
  352. {
  353. u32 ebci;
  354. /* enable interrupts on buffer transfer completion & error */
  355. ebci = AT_DMA_BTC(chan_id)
  356. | AT_DMA_ERR(chan_id);
  357. if (on)
  358. dma_writel(atdma, EBCIER, ebci);
  359. else
  360. dma_writel(atdma, EBCIDR, ebci);
  361. }
  362. static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
  363. {
  364. atc_setup_irq(atdma, chan_id, 1);
  365. }
  366. static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
  367. {
  368. atc_setup_irq(atdma, chan_id, 0);
  369. }
  370. /**
  371. * atc_chan_is_enabled - test if given channel is enabled
  372. * @atchan: channel we want to test status
  373. */
  374. static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
  375. {
  376. struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
  377. return !!(dma_readl(atdma, CHSR) & atchan->mask);
  378. }
  379. /**
  380. * atc_chan_is_paused - test channel pause/resume status
  381. * @atchan: channel we want to test status
  382. */
  383. static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
  384. {
  385. return test_bit(ATC_IS_PAUSED, &atchan->status);
  386. }
  387. /**
  388. * atc_chan_is_cyclic - test if given channel has cyclic property set
  389. * @atchan: channel we want to test status
  390. */
  391. static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
  392. {
  393. return test_bit(ATC_IS_CYCLIC, &atchan->status);
  394. }
  395. /**
  396. * set_desc_eol - set end-of-link to descriptor so it will end transfer
  397. * @desc: descriptor, signle or at the end of a chain, to end chain on
  398. */
  399. static void set_desc_eol(struct at_desc *desc)
  400. {
  401. u32 ctrlb = desc->lli.ctrlb;
  402. ctrlb &= ~ATC_IEN;
  403. ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
  404. desc->lli.ctrlb = ctrlb;
  405. desc->lli.dscr = 0;
  406. }
  407. #endif /* AT_HDMAC_REGS_H */