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