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 #define ATC_SRC_PIP             (0x1 <<  8)     /* Source Picture-in-Picture enabled */
 107 #define ATC_DST_PIP             (0x1 << 12)     /* Destination Picture-in-Picture enabled */
 108 #define ATC_SRC_DSCR_DIS        (0x1 << 16)     /* Src Descriptor fetch disable */
 109 #define ATC_DST_DSCR_DIS        (0x1 << 20)     /* Dst Descriptor fetch disable */
 110 #define ATC_FC_MASK             (0x7 << 21)     /* Choose Flow Controller */
 111 #define         ATC_FC_MEM2MEM          (0x0 << 21)     /* Mem-to-Mem (DMA) */
 112 #define         ATC_FC_MEM2PER          (0x1 << 21)     /* Mem-to-Periph (DMA) */
 113 #define         ATC_FC_PER2MEM          (0x2 << 21)     /* Periph-to-Mem (DMA) */
 114 #define         ATC_FC_PER2PER          (0x3 << 21)     /* Periph-to-Periph (DMA) */
 115 #define         ATC_FC_PER2MEM_PER      (0x4 << 21)     /* Periph-to-Mem (Peripheral) */
 116 #define         ATC_FC_MEM2PER_PER      (0x5 << 21)     /* Mem-to-Periph (Peripheral) */
 117 #define         ATC_FC_PER2PER_SRCPER   (0x6 << 21)     /* Periph-to-Periph (Src Peripheral) */
 118 #define         ATC_FC_PER2PER_DSTPER   (0x7 << 21)     /* Periph-to-Periph (Dst Peripheral) */
 119 #define ATC_SRC_ADDR_MODE_MASK  (0x3 << 24)
 120 #define         ATC_SRC_ADDR_MODE_INCR  (0x0 << 24)     /* Incrementing Mode */
 121 #define         ATC_SRC_ADDR_MODE_DECR  (0x1 << 24)     /* Decrementing Mode */
 122 #define         ATC_SRC_ADDR_MODE_FIXED (0x2 << 24)     /* Fixed Mode */
 123 #define ATC_DST_ADDR_MODE_MASK  (0x3 << 28)
 124 #define         ATC_DST_ADDR_MODE_INCR  (0x0 << 28)     /* Incrementing Mode */
 125 #define         ATC_DST_ADDR_MODE_DECR  (0x1 << 28)     /* Decrementing Mode */
 126 #define         ATC_DST_ADDR_MODE_FIXED (0x2 << 28)     /* Fixed Mode */
 127 #define ATC_IEN                 (0x1 << 30)     /* BTC interrupt enable (active low) */
 128 #define ATC_AUTO                (0x1 << 31)     /* Auto multiple buffer tx enable */
 129
 130 /* Bitfields in CFG */
 131 /* are in at_hdmac.h */
 132
 133 /* Bitfields in SPIP */
 134 #define ATC_SPIP_HOLE(x)        (0xFFFFU & (x))
 135 #define ATC_SPIP_BOUNDARY(x)    ((0x3FF & (x)) << 16)
 136
 137 /* Bitfields in DPIP */
 138 #define ATC_DPIP_HOLE(x)        (0xFFFFU & (x))
 139 #define ATC_DPIP_BOUNDARY(x)    ((0x3FF & (x)) << 16)
 140
 141
 142 /*--  descriptors  -----------------------------------------------------*/
 143
 144 /* LLI == Linked List Item; aka DMA buffer descriptor */
 145 struct at_lli {
 146         /* values that are not changed by hardware */
 147         dma_addr_t      saddr;
 148         dma_addr_t      daddr;
 149         /* value that may get written back: */
 150         u32             ctrla;
 151         /* more values that are not changed by hardware */
 152         u32             ctrlb;
 153         dma_addr_t      dscr;   /* chain to next lli */
 154 };
 155
 156 /**
 157  * struct at_desc - software descriptor
 158  * @at_lli: hardware lli structure
 159  * @txd: support for the async_tx api
 160  * @desc_node: node on the channed descriptors list
 161  * @len: total transaction bytecount
 162  */
 163 struct at_desc {
 164         /* FIRST values the hardware uses */
 165         struct at_lli                   lli;
 166
 167         /* THEN values for driver housekeeping */
 168         struct list_head                tx_list;
 169         struct dma_async_tx_descriptor  txd;
 170         struct list_head                desc_node;
 171         size_t                          len;
 172 };
 173
 174 static inline struct at_desc *
 175 txd_to_at_desc(struct dma_async_tx_descriptor *txd)
 176 {
 177         return container_of(txd, struct at_desc, txd);
 178 }
 179
 180
 181 /*--  Channels  --------------------------------------------------------*/
 182
 183 /**
 184  * struct at_dma_chan - internal representation of an Atmel HDMAC channel
 185  * @chan_common: common dmaengine channel object members
 186  * @device: parent device
 187  * @ch_regs: memory mapped register base
 188  * @mask: channel index in a mask
 189  * @error_status: transmit error status information from irq handler
 190  *                to tasklet (use atomic operations)
 191  * @tasklet: bottom half to finish transaction work
 192  * @lock: serializes enqueue/dequeue operations to descriptors lists
 193  * @completed_cookie: identifier for the most recently completed operation
 194  * @active_list: list of descriptors dmaengine is being running on
 195  * @queue: list of descriptors ready to be submitted to engine
 196  * @free_list: list of descriptors usable by the channel
 197  * @descs_allocated: records the actual size of the descriptor pool
 198  */
 199 struct at_dma_chan {
 200         struct dma_chan         chan_common;
 201         struct at_dma           *device;
 202         void __iomem            *ch_regs;
 203         u8                      mask;
 204         unsigned long           error_status;
 205         struct tasklet_struct   tasklet;
 206
 207         spinlock_t              lock;
 208
 209         /* these other elements are all protected by lock */
 210         dma_cookie_t            completed_cookie;
 211         struct list_head        active_list;
 212         struct list_head        queue;
 213         struct list_head        free_list;
 214         unsigned int            descs_allocated;
 215 };
 216
 217 #define channel_readl(atchan, name) \
 218         __raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
 219
 220 #define channel_writel(atchan, name, val) \
 221         __raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
 222
 223 static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
 224 {
 225         return container_of(dchan, struct at_dma_chan, chan_common);
 226 }
 227
 228
 229 /*--  Controller  ------------------------------------------------------*/
 230
 231 /**
 232  * struct at_dma - internal representation of an Atmel HDMA Controller
 233  * @chan_common: common dmaengine dma_device object members
 234  * @ch_regs: memory mapped register base
 235  * @clk: dma controller clock
 236  * @all_chan_mask: all channels availlable in a mask
 237  * @dma_desc_pool: base of DMA descriptor region (DMA address)
 238  * @chan: channels table to store at_dma_chan structures
 239  */
 240 struct at_dma {
 241         struct dma_device       dma_common;
 242         void __iomem            *regs;
 243         struct clk              *clk;
 244
 245         u8                      all_chan_mask;
 246
 247         struct dma_pool         *dma_desc_pool;
 248         /* AT THE END channels table */
 249         struct at_dma_chan      chan[0];
 250 };
 251
 252 #define dma_readl(atdma, name) \
 253         __raw_readl((atdma)->regs + AT_DMA_##name)
 254 #define dma_writel(atdma, name, val) \
 255         __raw_writel((val), (atdma)->regs + AT_DMA_##name)
 256
 257 static inline struct at_dma *to_at_dma(struct dma_device *ddev)
 258 {
 259         return container_of(ddev, struct at_dma, dma_common);
 260 }
 261
 262
 263 /*--  Helper functions  ------------------------------------------------*/
 264
 265 static struct device *chan2dev(struct dma_chan *chan)
 266 {
 267         return &chan->dev->device;
 268 }
 269 static struct device *chan2parent(struct dma_chan *chan)
 270 {
 271         return chan->dev->device.parent;
 272 }
 273
 274 #if defined(VERBOSE_DEBUG)
 275 static void vdbg_dump_regs(struct at_dma_chan *atchan)
 276 {
 277         struct at_dma   *atdma = to_at_dma(atchan->chan_common.device);
 278
 279         dev_err(chan2dev(&atchan->chan_common),
 280                 "  channel %d : imr = 0x%x, chsr = 0x%x\n",
 281                 atchan->chan_common.chan_id,
 282                 dma_readl(atdma, EBCIMR),
 283                 dma_readl(atdma, CHSR));
 284
 285         dev_err(chan2dev(&atchan->chan_common),
 286                 "  channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
 287                 channel_readl(atchan, SADDR),
 288                 channel_readl(atchan, DADDR),
 289                 channel_readl(atchan, CTRLA),
 290                 channel_readl(atchan, CTRLB),
 291                 channel_readl(atchan, CFG),
 292                 channel_readl(atchan, DSCR));
 293 }
 294 #else
 295 static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
 296 #endif
 297
 298 static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
 299 {
 300         dev_printk(KERN_CRIT, chan2dev(&atchan->chan_common),
 301                         "  desc: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n",
 302                         lli->saddr, lli->daddr,
 303                         lli->ctrla, lli->ctrlb, lli->dscr);
 304 }
 305
 306
 307 static void atc_setup_irq(struct at_dma_chan *atchan, int on)
 308 {
 309         struct at_dma   *atdma = to_at_dma(atchan->chan_common.device);
 310         u32             ebci;
 311
 312         /* enable interrupts on buffer transfer completion & error */
 313         ebci =    AT_DMA_BTC(atchan->chan_common.chan_id)
 314                 | AT_DMA_ERR(atchan->chan_common.chan_id);
 315         if (on)
 316                 dma_writel(atdma, EBCIER, ebci);
 317         else
 318                 dma_writel(atdma, EBCIDR, ebci);
 319 }
 320
 321 static inline void atc_enable_irq(struct at_dma_chan *atchan)
 322 {
 323         atc_setup_irq(atchan, 1);
 324 }
 325
 326 static inline void atc_disable_irq(struct at_dma_chan *atchan)
 327 {
 328         atc_setup_irq(atchan, 0);
 329 }
 330
 331
 332 /**
 333  * atc_chan_is_enabled - test if given channel is enabled
 334  * @atchan: channel we want to test status
 335  */
 336 static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
 337 {
 338         struct at_dma   *atdma = to_at_dma(atchan->chan_common.device);
 339
 340         return !!(dma_readl(atdma, CHSR) & atchan->mask);
 341 }
 342
 343
 344 /**
 345  * set_desc_eol - set end-of-link to descriptor so it will end transfer
 346  * @desc: descriptor, signle or at the end of a chain, to end chain on
 347  */
 348 static void set_desc_eol(struct at_desc *desc)
 349 {
 350         u32 ctrlb = desc->lli.ctrlb;
 351
 352         ctrlb &= ~ATC_IEN;
 353         ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
 354
 355         desc->lli.ctrlb = ctrlb;
 356         desc->lli.dscr = 0;
 357 }
 358
 359 #endif /* AT_HDMAC_REGS_H */