123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236 |
- /*
- * Driver for the Synopsys DesignWare AHB DMA Controller
- *
- * Copyright (C) 2005-2007 Atmel Corporation
- * Copyright (C) 2010-2011 ST Microelectronics
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
- #include <linux/dw_dmac.h>
- #define DW_DMA_MAX_NR_CHANNELS 8
- /*
- * Redefine this macro to handle differences between 32- and 64-bit
- * addressing, big vs. little endian, etc.
- */
- #define DW_REG(name) u32 name; u32 __pad_##name
- /* Hardware register definitions. */
- struct dw_dma_chan_regs {
- DW_REG(SAR); /* Source Address Register */
- DW_REG(DAR); /* Destination Address Register */
- DW_REG(LLP); /* Linked List Pointer */
- u32 CTL_LO; /* Control Register Low */
- u32 CTL_HI; /* Control Register High */
- DW_REG(SSTAT);
- DW_REG(DSTAT);
- DW_REG(SSTATAR);
- DW_REG(DSTATAR);
- u32 CFG_LO; /* Configuration Register Low */
- u32 CFG_HI; /* Configuration Register High */
- DW_REG(SGR);
- DW_REG(DSR);
- };
- struct dw_dma_irq_regs {
- DW_REG(XFER);
- DW_REG(BLOCK);
- DW_REG(SRC_TRAN);
- DW_REG(DST_TRAN);
- DW_REG(ERROR);
- };
- struct dw_dma_regs {
- /* per-channel registers */
- struct dw_dma_chan_regs CHAN[DW_DMA_MAX_NR_CHANNELS];
- /* irq handling */
- struct dw_dma_irq_regs RAW; /* r */
- struct dw_dma_irq_regs STATUS; /* r (raw & mask) */
- struct dw_dma_irq_regs MASK; /* rw (set = irq enabled) */
- struct dw_dma_irq_regs CLEAR; /* w (ack, affects "raw") */
- DW_REG(STATUS_INT); /* r */
- /* software handshaking */
- DW_REG(REQ_SRC);
- DW_REG(REQ_DST);
- DW_REG(SGL_REQ_SRC);
- DW_REG(SGL_REQ_DST);
- DW_REG(LAST_SRC);
- DW_REG(LAST_DST);
- /* miscellaneous */
- DW_REG(CFG);
- DW_REG(CH_EN);
- DW_REG(ID);
- DW_REG(TEST);
- /* optional encoded params, 0x3c8..0x3 */
- };
- /* Bitfields in CTL_LO */
- #define DWC_CTLL_INT_EN (1 << 0) /* irqs enabled? */
- #define DWC_CTLL_DST_WIDTH(n) ((n)<<1) /* bytes per element */
- #define DWC_CTLL_SRC_WIDTH(n) ((n)<<4)
- #define DWC_CTLL_DST_INC (0<<7) /* DAR update/not */
- #define DWC_CTLL_DST_DEC (1<<7)
- #define DWC_CTLL_DST_FIX (2<<7)
- #define DWC_CTLL_SRC_INC (0<<7) /* SAR update/not */
- #define DWC_CTLL_SRC_DEC (1<<9)
- #define DWC_CTLL_SRC_FIX (2<<9)
- #define DWC_CTLL_DST_MSIZE(n) ((n)<<11) /* burst, #elements */
- #define DWC_CTLL_SRC_MSIZE(n) ((n)<<14)
- #define DWC_CTLL_S_GATH_EN (1 << 17) /* src gather, !FIX */
- #define DWC_CTLL_D_SCAT_EN (1 << 18) /* dst scatter, !FIX */
- #define DWC_CTLL_FC(n) ((n) << 20)
- #define DWC_CTLL_FC_M2M (0 << 20) /* mem-to-mem */
- #define DWC_CTLL_FC_M2P (1 << 20) /* mem-to-periph */
- #define DWC_CTLL_FC_P2M (2 << 20) /* periph-to-mem */
- #define DWC_CTLL_FC_P2P (3 << 20) /* periph-to-periph */
- /* plus 4 transfer types for peripheral-as-flow-controller */
- #define DWC_CTLL_DMS(n) ((n)<<23) /* dst master select */
- #define DWC_CTLL_SMS(n) ((n)<<25) /* src master select */
- #define DWC_CTLL_LLP_D_EN (1 << 27) /* dest block chain */
- #define DWC_CTLL_LLP_S_EN (1 << 28) /* src block chain */
- /* Bitfields in CTL_HI */
- #define DWC_CTLH_DONE 0x00001000
- #define DWC_CTLH_BLOCK_TS_MASK 0x00000fff
- /* Bitfields in CFG_LO. Platform-configurable bits are in <linux/dw_dmac.h> */
- #define DWC_CFGL_CH_PRIOR_MASK (0x7 << 5) /* priority mask */
- #define DWC_CFGL_CH_PRIOR(x) ((x) << 5) /* priority */
- #define DWC_CFGL_CH_SUSP (1 << 8) /* pause xfer */
- #define DWC_CFGL_FIFO_EMPTY (1 << 9) /* pause xfer */
- #define DWC_CFGL_HS_DST (1 << 10) /* handshake w/dst */
- #define DWC_CFGL_HS_SRC (1 << 11) /* handshake w/src */
- #define DWC_CFGL_MAX_BURST(x) ((x) << 20)
- #define DWC_CFGL_RELOAD_SAR (1 << 30)
- #define DWC_CFGL_RELOAD_DAR (1 << 31)
- /* Bitfields in CFG_HI. Platform-configurable bits are in <linux/dw_dmac.h> */
- #define DWC_CFGH_DS_UPD_EN (1 << 5)
- #define DWC_CFGH_SS_UPD_EN (1 << 6)
- /* Bitfields in SGR */
- #define DWC_SGR_SGI(x) ((x) << 0)
- #define DWC_SGR_SGC(x) ((x) << 20)
- /* Bitfields in DSR */
- #define DWC_DSR_DSI(x) ((x) << 0)
- #define DWC_DSR_DSC(x) ((x) << 20)
- /* Bitfields in CFG */
- #define DW_CFG_DMA_EN (1 << 0)
- #define DW_REGLEN 0x400
- enum dw_dmac_flags {
- DW_DMA_IS_CYCLIC = 0,
- };
- struct dw_dma_chan {
- struct dma_chan chan;
- void __iomem *ch_regs;
- u8 mask;
- u8 priority;
- bool paused;
- spinlock_t lock;
- /* these other elements are all protected by lock */
- unsigned long flags;
- dma_cookie_t completed;
- struct list_head active_list;
- struct list_head queue;
- struct list_head free_list;
- struct dw_cyclic_desc *cdesc;
- unsigned int descs_allocated;
- };
- static inline struct dw_dma_chan_regs __iomem *
- __dwc_regs(struct dw_dma_chan *dwc)
- {
- return dwc->ch_regs;
- }
- #define channel_readl(dwc, name) \
- readl(&(__dwc_regs(dwc)->name))
- #define channel_writel(dwc, name, val) \
- writel((val), &(__dwc_regs(dwc)->name))
- static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan)
- {
- return container_of(chan, struct dw_dma_chan, chan);
- }
- struct dw_dma {
- struct dma_device dma;
- void __iomem *regs;
- struct tasklet_struct tasklet;
- struct clk *clk;
- u8 all_chan_mask;
- struct dw_dma_chan chan[0];
- };
- static inline struct dw_dma_regs __iomem *__dw_regs(struct dw_dma *dw)
- {
- return dw->regs;
- }
- #define dma_readl(dw, name) \
- readl(&(__dw_regs(dw)->name))
- #define dma_writel(dw, name, val) \
- writel((val), &(__dw_regs(dw)->name))
- #define channel_set_bit(dw, reg, mask) \
- dma_writel(dw, reg, ((mask) << 8) | (mask))
- #define channel_clear_bit(dw, reg, mask) \
- dma_writel(dw, reg, ((mask) << 8) | 0)
- static inline struct dw_dma *to_dw_dma(struct dma_device *ddev)
- {
- return container_of(ddev, struct dw_dma, dma);
- }
- /* LLI == Linked List Item; a.k.a. DMA block descriptor */
- struct dw_lli {
- /* values that are not changed by hardware */
- dma_addr_t sar;
- dma_addr_t dar;
- dma_addr_t llp; /* chain to next lli */
- u32 ctllo;
- /* values that may get written back: */
- u32 ctlhi;
- /* sstat and dstat can snapshot peripheral register state.
- * silicon config may discard either or both...
- */
- u32 sstat;
- u32 dstat;
- };
- struct dw_desc {
- /* FIRST values the hardware uses */
- struct dw_lli lli;
- /* THEN values for driver housekeeping */
- struct list_head desc_node;
- struct list_head tx_list;
- struct dma_async_tx_descriptor txd;
- size_t len;
- };
- static inline struct dw_desc *
- txd_to_dw_desc(struct dma_async_tx_descriptor *txd)
- {
- return container_of(txd, struct dw_desc, txd);
- }
|