drivers/dma/dw_dmac_regs.h

   1 /*
   2  * Driver for the Synopsys DesignWare AHB DMA Controller
   3  *
   4  * Copyright (C) 2005-2007 Atmel Corporation
   5  * Copyright (C) 2010-2011 ST Microelectronics
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/dw_dmac.h>
  13
  14 #define DW_DMA_MAX_NR_CHANNELS  8
  15
  16 /* flow controller */
  17 enum dw_dma_fc {
  18         DW_DMA_FC_D_M2M,
  19         DW_DMA_FC_D_M2P,
  20         DW_DMA_FC_D_P2M,
  21         DW_DMA_FC_D_P2P,
  22         DW_DMA_FC_P_P2M,
  23         DW_DMA_FC_SP_P2P,
  24         DW_DMA_FC_P_M2P,
  25         DW_DMA_FC_DP_P2P,
  26 };
  27
  28 /*
  29  * Redefine this macro to handle differences between 32- and 64-bit
  30  * addressing, big vs. little endian, etc.
  31  */
  32 #define DW_REG(name)            u32 name; u32 __pad_##name
  33
  34 /* Hardware register definitions. */
  35 struct dw_dma_chan_regs {
  36         DW_REG(SAR);            /* Source Address Register */
  37         DW_REG(DAR);            /* Destination Address Register */
  38         DW_REG(LLP);            /* Linked List Pointer */
  39         u32     CTL_LO;         /* Control Register Low */
  40         u32     CTL_HI;         /* Control Register High */
  41         DW_REG(SSTAT);
  42         DW_REG(DSTAT);
  43         DW_REG(SSTATAR);
  44         DW_REG(DSTATAR);
  45         u32     CFG_LO;         /* Configuration Register Low */
  46         u32     CFG_HI;         /* Configuration Register High */
  47         DW_REG(SGR);
  48         DW_REG(DSR);
  49 };
  50
  51 struct dw_dma_irq_regs {
  52         DW_REG(XFER);
  53         DW_REG(BLOCK);
  54         DW_REG(SRC_TRAN);
  55         DW_REG(DST_TRAN);
  56         DW_REG(ERROR);
  57 };
  58
  59 struct dw_dma_regs {
  60         /* per-channel registers */
  61         struct dw_dma_chan_regs CHAN[DW_DMA_MAX_NR_CHANNELS];
  62
  63         /* irq handling */
  64         struct dw_dma_irq_regs  RAW;            /* r */
  65         struct dw_dma_irq_regs  STATUS;         /* r (raw & mask) */
  66         struct dw_dma_irq_regs  MASK;           /* rw (set = irq enabled) */
  67         struct dw_dma_irq_regs  CLEAR;          /* w (ack, affects "raw") */
  68
  69         DW_REG(STATUS_INT);                     /* r */
  70
  71         /* software handshaking */
  72         DW_REG(REQ_SRC);
  73         DW_REG(REQ_DST);
  74         DW_REG(SGL_REQ_SRC);
  75         DW_REG(SGL_REQ_DST);
  76         DW_REG(LAST_SRC);
  77         DW_REG(LAST_DST);
  78
  79         /* miscellaneous */
  80         DW_REG(CFG);
  81         DW_REG(CH_EN);
  82         DW_REG(ID);
  83         DW_REG(TEST);
  84
  85         /* optional encoded params, 0x3c8..0x3 */
  86 };
  87
  88 /* Bitfields in CTL_LO */
  89 #define DWC_CTLL_INT_EN         (1 << 0)        /* irqs enabled? */
  90 #define DWC_CTLL_DST_WIDTH(n)   ((n)<<1)        /* bytes per element */
  91 #define DWC_CTLL_SRC_WIDTH(n)   ((n)<<4)
  92 #define DWC_CTLL_DST_INC        (0<<7)          /* DAR update/not */
  93 #define DWC_CTLL_DST_DEC        (1<<7)
  94 #define DWC_CTLL_DST_FIX        (2<<7)
  95 #define DWC_CTLL_SRC_INC        (0<<7)          /* SAR update/not */
  96 #define DWC_CTLL_SRC_DEC        (1<<9)
  97 #define DWC_CTLL_SRC_FIX        (2<<9)
  98 #define DWC_CTLL_DST_MSIZE(n)   ((n)<<11)       /* burst, #elements */
  99 #define DWC_CTLL_SRC_MSIZE(n)   ((n)<<14)
 100 #define DWC_CTLL_S_GATH_EN      (1 << 17)       /* src gather, !FIX */
 101 #define DWC_CTLL_D_SCAT_EN      (1 << 18)       /* dst scatter, !FIX */
 102 #define DWC_CTLL_FC(n)          ((n) << 20)
 103 #define DWC_CTLL_FC_M2M         (0 << 20)       /* mem-to-mem */
 104 #define DWC_CTLL_FC_M2P         (1 << 20)       /* mem-to-periph */
 105 #define DWC_CTLL_FC_P2M         (2 << 20)       /* periph-to-mem */
 106 #define DWC_CTLL_FC_P2P         (3 << 20)       /* periph-to-periph */
 107 /* plus 4 transfer types for peripheral-as-flow-controller */
 108 #define DWC_CTLL_DMS(n)         ((n)<<23)       /* dst master select */
 109 #define DWC_CTLL_SMS(n)         ((n)<<25)       /* src master select */
 110 #define DWC_CTLL_LLP_D_EN       (1 << 27)       /* dest block chain */
 111 #define DWC_CTLL_LLP_S_EN       (1 << 28)       /* src block chain */
 112
 113 /* Bitfields in CTL_HI */
 114 #define DWC_CTLH_DONE           0x00001000
 115 #define DWC_CTLH_BLOCK_TS_MASK  0x00000fff
 116
 117 /* Bitfields in CFG_LO. Platform-configurable bits are in <linux/dw_dmac.h> */
 118 #define DWC_CFGL_CH_PRIOR_MASK  (0x7 << 5)      /* priority mask */
 119 #define DWC_CFGL_CH_PRIOR(x)    ((x) << 5)      /* priority */
 120 #define DWC_CFGL_CH_SUSP        (1 << 8)        /* pause xfer */
 121 #define DWC_CFGL_FIFO_EMPTY     (1 << 9)        /* pause xfer */
 122 #define DWC_CFGL_HS_DST         (1 << 10)       /* handshake w/dst */
 123 #define DWC_CFGL_HS_SRC         (1 << 11)       /* handshake w/src */
 124 #define DWC_CFGL_MAX_BURST(x)   ((x) << 20)
 125 #define DWC_CFGL_RELOAD_SAR     (1 << 30)
 126 #define DWC_CFGL_RELOAD_DAR     (1 << 31)
 127
 128 /* Bitfields in CFG_HI. Platform-configurable bits are in <linux/dw_dmac.h> */
 129 #define DWC_CFGH_DS_UPD_EN      (1 << 5)
 130 #define DWC_CFGH_SS_UPD_EN      (1 << 6)
 131
 132 /* Bitfields in SGR */
 133 #define DWC_SGR_SGI(x)          ((x) << 0)
 134 #define DWC_SGR_SGC(x)          ((x) << 20)
 135
 136 /* Bitfields in DSR */
 137 #define DWC_DSR_DSI(x)          ((x) << 0)
 138 #define DWC_DSR_DSC(x)          ((x) << 20)
 139
 140 /* Bitfields in CFG */
 141 #define DW_CFG_DMA_EN           (1 << 0)
 142
 143 #define DW_REGLEN               0x400
 144
 145 enum dw_dmac_flags {
 146         DW_DMA_IS_CYCLIC = 0,
 147 };
 148
 149 struct dw_dma_chan {
 150         struct dma_chan         chan;
 151         void __iomem            *ch_regs;
 152         u8                      mask;
 153         u8                      priority;
 154         bool                    paused;
 155         bool                    initialized;
 156
 157         spinlock_t              lock;
 158
 159         /* these other elements are all protected by lock */
 160         unsigned long           flags;
 161         struct list_head        active_list;
 162         struct list_head        queue;
 163         struct list_head        free_list;
 164         struct dw_cyclic_desc   *cdesc;
 165
 166         unsigned int            descs_allocated;
 167
 168         /* configuration passed via DMA_SLAVE_CONFIG */
 169         struct dma_slave_config dma_sconfig;
 170 };
 171
 172 static inline struct dw_dma_chan_regs __iomem *
 173 __dwc_regs(struct dw_dma_chan *dwc)
 174 {
 175         return dwc->ch_regs;
 176 }
 177
 178 #define channel_readl(dwc, name) \
 179         readl(&(__dwc_regs(dwc)->name))
 180 #define channel_writel(dwc, name, val) \
 181         writel((val), &(__dwc_regs(dwc)->name))
 182
 183 static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan)
 184 {
 185         return container_of(chan, struct dw_dma_chan, chan);
 186 }
 187
 188 struct dw_dma {
 189         struct dma_device       dma;
 190         void __iomem            *regs;
 191         struct tasklet_struct   tasklet;
 192         struct clk              *clk;
 193
 194         u8                      all_chan_mask;
 195
 196         struct dw_dma_chan      chan[0];
 197 };
 198
 199 static inline struct dw_dma_regs __iomem *__dw_regs(struct dw_dma *dw)
 200 {
 201         return dw->regs;
 202 }
 203
 204 #define dma_readl(dw, name) \
 205         readl(&(__dw_regs(dw)->name))
 206 #define dma_writel(dw, name, val) \
 207         writel((val), &(__dw_regs(dw)->name))
 208
 209 #define channel_set_bit(dw, reg, mask) \
 210         dma_writel(dw, reg, ((mask) << 8) | (mask))
 211 #define channel_clear_bit(dw, reg, mask) \
 212         dma_writel(dw, reg, ((mask) << 8) | 0)
 213
 214 static inline struct dw_dma *to_dw_dma(struct dma_device *ddev)
 215 {
 216         return container_of(ddev, struct dw_dma, dma);
 217 }
 218
 219 /* LLI == Linked List Item; a.k.a. DMA block descriptor */
 220 struct dw_lli {
 221         /* values that are not changed by hardware */
 222         dma_addr_t      sar;
 223         dma_addr_t      dar;
 224         dma_addr_t      llp;            /* chain to next lli */
 225         u32             ctllo;
 226         /* values that may get written back: */
 227         u32             ctlhi;
 228         /* sstat and dstat can snapshot peripheral register state.
 229          * silicon config may discard either or both...
 230          */
 231         u32             sstat;
 232         u32             dstat;
 233 };
 234
 235 struct dw_desc {
 236         /* FIRST values the hardware uses */
 237         struct dw_lli                   lli;
 238
 239         /* THEN values for driver housekeeping */
 240         struct list_head                desc_node;
 241         struct list_head                tx_list;
 242         struct dma_async_tx_descriptor  txd;
 243         size_t                          len;
 244 };
 245
 246 static inline struct dw_desc *
 247 txd_to_dw_desc(struct dma_async_tx_descriptor *txd)
 248 {
 249         return container_of(txd, struct dw_desc, txd);
 250 }