drivers/dma/at_hdmac_regs.h

   1 /*
   2  * Header file for the Atmel AHB DMA Controller driver
   3  *
   4  * Copyright (C) 2008 Atmel Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11 #ifndef AT_HDMAC_REGS_H
  12 #define AT_HDMAC_REGS_H
  13
  14 #include <mach/at_hdmac.h>
  15
  16 #define AT_DMA_MAX_NR_CHANNELS  8
  17
  18
  19 #define AT_DMA_GCFG     0x00    /* Global Configuration Register */
  20 #define         AT_DMA_IF_BIGEND(i)     (0x1 << (i))    /* AHB-Lite Interface i in Big-endian mode */
  21 #define         AT_DMA_ARB_CFG  (0x1 << 4)      /* Arbiter mode. */
  22 #define                 AT_DMA_ARB_CFG_FIXED            (0x0 << 4)
  23 #define                 AT_DMA_ARB_CFG_ROUND_ROBIN      (0x1 << 4)
  24
  25 #define AT_DMA_EN       0x04    /* Controller Enable Register */
  26 #define         AT_DMA_ENABLE   (0x1 << 0)
  27
  28 #define AT_DMA_SREQ     0x08    /* Software Single Request Register */
  29 #define         AT_DMA_SSREQ(x) (0x1 << ((x) << 1))             /* Request a source single transfer on channel x */
  30 #define         AT_DMA_DSREQ(x) (0x1 << (1 + ((x) << 1)))       /* Request a destination single transfer on channel x */
  31
  32 #define AT_DMA_CREQ     0x0C    /* Software Chunk Transfer Request Register */
  33 #define         AT_DMA_SCREQ(x) (0x1 << ((x) << 1))             /* Request a source chunk transfer on channel x */
  34 #define         AT_DMA_DCREQ(x) (0x1 << (1 + ((x) << 1)))       /* Request a destination chunk transfer on channel x */
  35
  36 #define AT_DMA_LAST     0x10    /* Software Last Transfer Flag Register */
  37 #define         AT_DMA_SLAST(x) (0x1 << ((x) << 1))             /* This src rq is last tx of buffer on channel x */
  38 #define         AT_DMA_DLAST(x) (0x1 << (1 + ((x) << 1)))       /* This dst rq is last tx of buffer on channel x */
  39
  40 #define AT_DMA_SYNC     0x14    /* Request Synchronization Register */
  41 #define         AT_DMA_SYR(h)   (0x1 << (h))                    /* Synchronize handshake line h */
  42
  43 /* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
  44 #define AT_DMA_EBCIER   0x18    /* Enable register */
  45 #define AT_DMA_EBCIDR   0x1C    /* Disable register */
  46 #define AT_DMA_EBCIMR   0x20    /* Mask Register */
  47 #define AT_DMA_EBCISR   0x24    /* Status Register */
  48 #define         AT_DMA_CBTC_OFFSET      8
  49 #define         AT_DMA_ERR_OFFSET       16
  50 #define         AT_DMA_BTC(x)   (0x1 << (x))
  51 #define         AT_DMA_CBTC(x)  (0x1 << (AT_DMA_CBTC_OFFSET + (x)))
  52 #define         AT_DMA_ERR(x)   (0x1 << (AT_DMA_ERR_OFFSET + (x)))
  53
  54 #define AT_DMA_CHER     0x28    /* Channel Handler Enable Register */
  55 #define         AT_DMA_ENA(x)   (0x1 << (x))
  56 #define         AT_DMA_SUSP(x)  (0x1 << ( 8 + (x)))
  57 #define         AT_DMA_KEEP(x)  (0x1 << (24 + (x)))
  58
  59 #define AT_DMA_CHDR     0x2C    /* Channel Handler Disable Register */
  60 #define         AT_DMA_DIS(x)   (0x1 << (x))
  61 #define         AT_DMA_RES(x)   (0x1 << ( 8 + (x)))
  62
  63 #define AT_DMA_CHSR     0x30    /* Channel Handler Status Register */
  64 #define         AT_DMA_EMPT(x)  (0x1 << (16 + (x)))
  65 #define         AT_DMA_STAL(x)  (0x1 << (24 + (x)))
  66
  67
  68 #define AT_DMA_CH_REGS_BASE     0x3C    /* Channel registers base address */
  69 #define ch_regs(x)      (AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
  70
  71 /* Hardware register offset for each channel */
  72 #define ATC_SADDR_OFFSET        0x00    /* Source Address Register */
  73 #define ATC_DADDR_OFFSET        0x04    /* Destination Address Register */
  74 #define ATC_DSCR_OFFSET         0x08    /* Descriptor Address Register */
  75 #define ATC_CTRLA_OFFSET        0x0C    /* Control A Register */
  76 #define ATC_CTRLB_OFFSET        0x10    /* Control B Register */
  77 #define ATC_CFG_OFFSET          0x14    /* Configuration Register */
  78 #define ATC_SPIP_OFFSET         0x18    /* Src PIP Configuration Register */
  79 #define ATC_DPIP_OFFSET         0x1C    /* Dst PIP Configuration Register */
  80
  81
  82 /* Bitfield definitions */
  83
  84 /* Bitfields in DSCR */
  85 #define ATC_DSCR_IF(i)          (0x3 & (i))     /* Dsc feched via AHB-Lite Interface i */
  86
  87 /* Bitfields in CTRLA */
  88 #define ATC_BTSIZE_MAX          0xFFFFUL        /* Maximum Buffer Transfer Size */
  89 #define ATC_BTSIZE(x)           (ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
  90 /* Chunck Tranfer size definitions are in at_hdmac.h */
  91 #define ATC_SRC_WIDTH_MASK      (0x3 << 24)     /* Source Single Transfer Size */
  92 #define         ATC_SRC_WIDTH(x)        ((x) << 24)
  93 #define         ATC_SRC_WIDTH_BYTE      (0x0 << 24)
  94 #define         ATC_SRC_WIDTH_HALFWORD  (0x1 << 24)
  95 #define         ATC_SRC_WIDTH_WORD      (0x2 << 24)
  96 #define ATC_DST_WIDTH_MASK      (0x3 << 28)     /* Destination Single Transfer Size */
  97 #define         ATC_DST_WIDTH(x)        ((x) << 28)
  98 #define         ATC_DST_WIDTH_BYTE      (0x0 << 28)
  99 #define         ATC_DST_WIDTH_HALFWORD  (0x1 << 28)
 100 #define         ATC_DST_WIDTH_WORD      (0x2 << 28)
 101 #define ATC_DONE                (0x1 << 31)     /* Tx Done (only written back in descriptor) */
 102
 103 /* Bitfields in CTRLB */
 104 #define ATC_SIF(i)              (0x3 & (i))     /* Src tx done via AHB-Lite Interface i */
 105 #define ATC_DIF(i)              ((0x3 & (i)) <<  4)     /* Dst tx done via AHB-Lite Interface i */
 106                                   /* Specify AHB interfaces */
 107 #define AT_DMA_MEM_IF           0 /* interface 0 as memory interface */
 108 #define AT_DMA_PER_IF           1 /* interface 1 as peripheral interface */
 109
 110 #define ATC_SRC_PIP             (0x1 <<  8)     /* Source Picture-in-Picture enabled */
 111 #define ATC_DST_PIP             (0x1 << 12)     /* Destination Picture-in-Picture enabled */
 112 #define ATC_SRC_DSCR_DIS        (0x1 << 16)     /* Src Descriptor fetch disable */
 113 #define ATC_DST_DSCR_DIS        (0x1 << 20)     /* Dst Descriptor fetch disable */
 114 #define ATC_FC_MASK             (0x7 << 21)     /* Choose Flow Controller */
 115 #define         ATC_FC_MEM2MEM          (0x0 << 21)     /* Mem-to-Mem (DMA) */
 116 #define         ATC_FC_MEM2PER          (0x1 << 21)     /* Mem-to-Periph (DMA) */
 117 #define         ATC_FC_PER2MEM          (0x2 << 21)     /* Periph-to-Mem (DMA) */
 118 #define         ATC_FC_PER2PER          (0x3 << 21)     /* Periph-to-Periph (DMA) */
 119 #define         ATC_FC_PER2MEM_PER      (0x4 << 21)     /* Periph-to-Mem (Peripheral) */
 120 #define         ATC_FC_MEM2PER_PER      (0x5 << 21)     /* Mem-to-Periph (Peripheral) */
 121 #define         ATC_FC_PER2PER_SRCPER   (0x6 << 21)     /* Periph-to-Periph (Src Peripheral) */
 122 #define         ATC_FC_PER2PER_DSTPER   (0x7 << 21)     /* Periph-to-Periph (Dst Peripheral) */
 123 #define ATC_SRC_ADDR_MODE_MASK  (0x3 << 24)
 124 #define         ATC_SRC_ADDR_MODE_INCR  (0x0 << 24)     /* Incrementing Mode */
 125 #define         ATC_SRC_ADDR_MODE_DECR  (0x1 << 24)     /* Decrementing Mode */
 126 #define         ATC_SRC_ADDR_MODE_FIXED (0x2 << 24)     /* Fixed Mode */
 127 #define ATC_DST_ADDR_MODE_MASK  (0x3 << 28)
 128 #define         ATC_DST_ADDR_MODE_INCR  (0x0 << 28)     /* Incrementing Mode */
 129 #define         ATC_DST_ADDR_MODE_DECR  (0x1 << 28)     /* Decrementing Mode */
 130 #define         ATC_DST_ADDR_MODE_FIXED (0x2 << 28)     /* Fixed Mode */
 131 #define ATC_IEN                 (0x1 << 30)     /* BTC interrupt enable (active low) */
 132 #define ATC_AUTO                (0x1 << 31)     /* Auto multiple buffer tx enable */
 133
 134 /* Bitfields in CFG */
 135 /* are in at_hdmac.h */
 136
 137 /* Bitfields in SPIP */
 138 #define ATC_SPIP_HOLE(x)        (0xFFFFU & (x))
 139 #define ATC_SPIP_BOUNDARY(x)    ((0x3FF & (x)) << 16)
 140
 141 /* Bitfields in DPIP */
 142 #define ATC_DPIP_HOLE(x)        (0xFFFFU & (x))
 143 #define ATC_DPIP_BOUNDARY(x)    ((0x3FF & (x)) << 16)
 144
 145
 146 /*--  descriptors  -----------------------------------------------------*/
 147
 148 /* LLI == Linked List Item; aka DMA buffer descriptor */
 149 struct at_lli {
 150         /* values that are not changed by hardware */
 151         dma_addr_t      saddr;
 152         dma_addr_t      daddr;
 153         /* value that may get written back: */
 154         u32             ctrla;
 155         /* more values that are not changed by hardware */
 156         u32             ctrlb;
 157         dma_addr_t      dscr;   /* chain to next lli */
 158 };
 159
 160 /**
 161  * struct at_desc - software descriptor
 162  * @at_lli: hardware lli structure
 163  * @txd: support for the async_tx api
 164  * @desc_node: node on the channed descriptors list
 165  * @len: total transaction bytecount
 166  */
 167 struct at_desc {
 168         /* FIRST values the hardware uses */
 169         struct at_lli                   lli;
 170
 171         /* THEN values for driver housekeeping */
 172         struct list_head                tx_list;
 173         struct dma_async_tx_descriptor  txd;
 174         struct list_head                desc_node;
 175         size_t                          len;
 176 };
 177
 178 static inline struct at_desc *
 179 txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 180 {
 181         return container_of(txd, struct at_desc, txd);
 182 }
 183
 184
 185 /*--  Channels  --------------------------------------------------------*/
 186
 187 /**
 188  * atc_status - information bits stored in channel status flag
 189  *
 190  * Manipulated with atomic operations.
 191  */
 192 enum atc_status {
 193         ATC_IS_ERROR = 0,
 194         ATC_IS_PAUSED = 1,
 195         ATC_IS_CYCLIC = 24,
 196 };
 197
 198 /**
 199  * struct at_dma_chan - internal representation of an Atmel HDMAC channel
 200  * @chan_common: common dmaengine channel object members
 201  * @device: parent device
 202  * @ch_regs: memory mapped register base
 203  * @mask: channel index in a mask
 204  * @status: transmit status information from irq/prep* functions
 205  *                to tasklet (use atomic operations)
 206  * @tasklet: bottom half to finish transaction work
 207  * @save_cfg: configuration register that is saved on suspend/resume cycle
 208  * @save_dscr: for cyclic operations, preserve next descriptor address in
 209  *             the cyclic list on suspend/resume cycle
 210  * @dma_sconfig: configuration for slave transfers, passed via DMA_SLAVE_CONFIG
 211  * @lock: serializes enqueue/dequeue operations to descriptors lists
 212  * @active_list: list of descriptors dmaengine is being running on
 213  * @queue: list of descriptors ready to be submitted to engine
 214  * @free_list: list of descriptors usable by the channel
 215  * @descs_allocated: records the actual size of the descriptor pool
 216  */
 217 struct at_dma_chan {
 218         struct dma_chan         chan_common;
 219         struct at_dma           *device;
 220         void __iomem            *ch_regs;
 221         u8                      mask;
 222         unsigned long           status;
 223         struct tasklet_struct   tasklet;
 224         u32                     save_cfg;
 225         u32                     save_dscr;
 226         struct dma_slave_config dma_sconfig;
 227
 228         spinlock_t              lock;
 229
 230         /* these other elements are all protected by lock */
 231         struct list_head        active_list;
 232         struct list_head        queue;
 233         struct list_head        free_list;
 234         unsigned int            descs_allocated;
 235 };
 236
 237 #define channel_readl(atchan, name) \
 238         __raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
 239
 240 #define channel_writel(atchan, name, val) \
 241         __raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
 242
 243 static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
 244 {
 245         return container_of(dchan, struct at_dma_chan, chan_common);
 246 }
 247
 248 /*
 249  * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
 250  * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
 251  *
 252  * This can be done by finding most significant bit set.
 253  */
 254 static inline void convert_burst(u32 *maxburst)
 255 {
 256         if (*maxburst > 1)
 257                 *maxburst = fls(*maxburst) - 2;
 258         else
 259                 *maxburst = 0;
 260 }
 261
 262 /*
 263  * Fix sconfig's bus width according to at_hdmac.
 264  * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
 265  */
 266 static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
 267 {
 268         switch (addr_width) {
 269         case DMA_SLAVE_BUSWIDTH_2_BYTES:
 270                 return 1;
 271         case DMA_SLAVE_BUSWIDTH_4_BYTES:
 272                 return 2;
 273         default:
 274                 /* For 1 byte width or fallback */
 275                 return 0;
 276         }
 277 }
 278
 279 /*--  Controller  ------------------------------------------------------*/
 280
 281 /**
 282  * struct at_dma - internal representation of an Atmel HDMA Controller
 283  * @chan_common: common dmaengine dma_device object members
 284  * @atdma_devtype: identifier of DMA controller compatibility
 285  * @ch_regs: memory mapped register base
 286  * @clk: dma controller clock
 287  * @save_imr: interrupt mask register that is saved on suspend/resume cycle
 288  * @all_chan_mask: all channels availlable in a mask
 289  * @dma_desc_pool: base of DMA descriptor region (DMA address)
 290  * @chan: channels table to store at_dma_chan structures
 291  */
 292 struct at_dma {
 293         struct dma_device       dma_common;
 294         void __iomem            *regs;
 295         struct clk              *clk;
 296         u32                     save_imr;
 297
 298         u8                      all_chan_mask;
 299
 300         struct dma_pool         *dma_desc_pool;
 301         /* AT THE END channels table */
 302         struct at_dma_chan      chan[0];
 303 };
 304
 305 #define dma_readl(atdma, name) \
 306         __raw_readl((atdma)->regs + AT_DMA_##name)
 307 #define dma_writel(atdma, name, val) \
 308         __raw_writel((val), (atdma)->regs + AT_DMA_##name)
 309
 310 static inline struct at_dma *to_at_dma(struct dma_device *ddev)
 311 {
 312         return container_of(ddev, struct at_dma, dma_common);
 313 }
 314
 315
 316 /*--  Helper functions  ------------------------------------------------*/
 317
 318 static struct device *chan2dev(struct dma_chan *chan)
 319 {
 320         return &chan->dev->device;
 321 }
 322 static struct device *chan2parent(struct dma_chan *chan)
 323 {
 324         return chan->dev->device.parent;
 325 }
 326
 327 #if defined(VERBOSE_DEBUG)
 328 static void vdbg_dump_regs(struct at_dma_chan *atchan)
 329 {
 330         struct at_dma   *atdma = to_at_dma(atchan->chan_common.device);
 331
 332         dev_err(chan2dev(&atchan->chan_common),
 333                 "  channel %d : imr = 0x%x, chsr = 0x%x\n",
 334                 atchan->chan_common.chan_id,
 335                 dma_readl(atdma, EBCIMR),
 336                 dma_readl(atdma, CHSR));
 337
 338         dev_err(chan2dev(&atchan->chan_common),
 339                 "  channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
 340                 channel_readl(atchan, SADDR),
 341                 channel_readl(atchan, DADDR),
 342                 channel_readl(atchan, CTRLA),
 343                 channel_readl(atchan, CTRLB),
 344                 channel_readl(atchan, CFG),
 345                 channel_readl(atchan, DSCR));
 346 }
 347 #else
 348 static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
 349 #endif
 350
 351 static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
 352 {
 353         dev_printk(KERN_CRIT, chan2dev(&atchan->chan_common),
 354                         "  desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
 355                         lli->saddr, lli->daddr,
 356                         lli->ctrla, lli->ctrlb, lli->dscr);
 357 }
 358
 359
 360 static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
 361 {
 362         u32 ebci;
 363
 364         /* enable interrupts on buffer transfer completion & error */
 365         ebci =    AT_DMA_BTC(chan_id)
 366                 | AT_DMA_ERR(chan_id);
 367         if (on)
 368                 dma_writel(atdma, EBCIER, ebci);
 369         else
 370                 dma_writel(atdma, EBCIDR, ebci);
 371 }
 372
 373 static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
 374 {
 375         atc_setup_irq(atdma, chan_id, 1);
 376 }
 377
 378 static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
 379 {
 380         atc_setup_irq(atdma, chan_id, 0);
 381 }
 382
 383
 384 /**
 385  * atc_chan_is_enabled - test if given channel is enabled
 386  * @atchan: channel we want to test status
 387  */
 388 static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
 389 {
 390         struct at_dma   *atdma = to_at_dma(atchan->chan_common.device);
 391
 392         return !!(dma_readl(atdma, CHSR) & atchan->mask);
 393 }
 394
 395 /**
 396  * atc_chan_is_paused - test channel pause/resume status
 397  * @atchan: channel we want to test status
 398  */
 399 static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
 400 {
 401         return test_bit(ATC_IS_PAUSED, &atchan->status);
 402 }
 403
 404 /**
 405  * atc_chan_is_cyclic - test if given channel has cyclic property set
 406  * @atchan: channel we want to test status
 407  */
 408 static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
 409 {
 410         return test_bit(ATC_IS_CYCLIC, &atchan->status);
 411 }
 412
 413 /**
 414  * set_desc_eol - set end-of-link to descriptor so it will end transfer
 415  * @desc: descriptor, signle or at the end of a chain, to end chain on
 416  */
 417 static void set_desc_eol(struct at_desc *desc)
 418 {
 419         u32 ctrlb = desc->lli.ctrlb;
 420
 421         ctrlb &= ~ATC_IEN;
 422         ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
 423
 424         desc->lli.ctrlb = ctrlb;
 425         desc->lli.dscr = 0;
 426 }
 427
 428 #endif /* AT_HDMAC_REGS_H */