2 * Driver for the Synopsys DesignWare AHB DMA Controller
4 * Copyright (C) 2005-2007 Atmel Corporation
5 * Copyright (C) 2010-2011 ST Microelectronics
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.
12 #include <linux/interrupt.h>
13 #include <linux/dmaengine.h>
17 #define DW_DMA_MAX_NR_REQUESTS 16
32 * Redefine this macro to handle differences between 32- and 64-bit
33 * addressing, big vs. little endian, etc.
35 #define DW_REG(name) u32 name; u32 __pad_##name
37 /* Hardware register definitions. */
38 struct dw_dma_chan_regs
{
39 DW_REG(SAR
); /* Source Address Register */
40 DW_REG(DAR
); /* Destination Address Register */
41 DW_REG(LLP
); /* Linked List Pointer */
42 u32 CTL_LO
; /* Control Register Low */
43 u32 CTL_HI
; /* Control Register High */
48 u32 CFG_LO
; /* Configuration Register Low */
49 u32 CFG_HI
; /* Configuration Register High */
54 struct dw_dma_irq_regs
{
63 /* per-channel registers */
64 struct dw_dma_chan_regs CHAN
[DW_DMA_MAX_NR_CHANNELS
];
67 struct dw_dma_irq_regs RAW
; /* r */
68 struct dw_dma_irq_regs STATUS
; /* r (raw & mask) */
69 struct dw_dma_irq_regs MASK
; /* rw (set = irq enabled) */
70 struct dw_dma_irq_regs CLEAR
; /* w (ack, affects "raw") */
72 DW_REG(STATUS_INT
); /* r */
74 /* software handshaking */
92 /* optional encoded params, 0x3c8..0x3f7 */
95 /* per-channel configuration registers */
96 u32 DWC_PARAMS
[DW_DMA_MAX_NR_CHANNELS
];
100 /* top-level parameters */
105 * Big endian I/O access when reading and writing to the DMA controller
106 * registers. This is needed on some platforms, like the Atmel AVR32
110 #ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
111 #define dma_readl_native ioread32be
112 #define dma_writel_native iowrite32be
114 #define dma_readl_native readl
115 #define dma_writel_native writel
118 /* Bitfields in DW_PARAMS */
119 #define DW_PARAMS_NR_CHAN 8 /* number of channels */
120 #define DW_PARAMS_NR_MASTER 11 /* number of AHB masters */
121 #define DW_PARAMS_DATA_WIDTH(n) (15 + 2 * (n))
122 #define DW_PARAMS_DATA_WIDTH1 15 /* master 1 data width */
123 #define DW_PARAMS_DATA_WIDTH2 17 /* master 2 data width */
124 #define DW_PARAMS_DATA_WIDTH3 19 /* master 3 data width */
125 #define DW_PARAMS_DATA_WIDTH4 21 /* master 4 data width */
126 #define DW_PARAMS_EN 28 /* encoded parameters */
128 /* Bitfields in DWC_PARAMS */
129 #define DWC_PARAMS_MBLK_EN 11 /* multi block transfer */
143 /* Bitfields in LLP */
144 #define DWC_LLP_LMS(x) ((x) & 3) /* list master select */
145 #define DWC_LLP_LOC(x) ((x) & ~3) /* next lli */
147 /* Bitfields in CTL_LO */
148 #define DWC_CTLL_INT_EN (1 << 0) /* irqs enabled? */
149 #define DWC_CTLL_DST_WIDTH(n) ((n)<<1) /* bytes per element */
150 #define DWC_CTLL_SRC_WIDTH(n) ((n)<<4)
151 #define DWC_CTLL_DST_INC (0<<7) /* DAR update/not */
152 #define DWC_CTLL_DST_DEC (1<<7)
153 #define DWC_CTLL_DST_FIX (2<<7)
154 #define DWC_CTLL_SRC_INC (0<<9) /* SAR update/not */
155 #define DWC_CTLL_SRC_DEC (1<<9)
156 #define DWC_CTLL_SRC_FIX (2<<9)
157 #define DWC_CTLL_DST_MSIZE(n) ((n)<<11) /* burst, #elements */
158 #define DWC_CTLL_SRC_MSIZE(n) ((n)<<14)
159 #define DWC_CTLL_S_GATH_EN (1 << 17) /* src gather, !FIX */
160 #define DWC_CTLL_D_SCAT_EN (1 << 18) /* dst scatter, !FIX */
161 #define DWC_CTLL_FC(n) ((n) << 20)
162 #define DWC_CTLL_FC_M2M (0 << 20) /* mem-to-mem */
163 #define DWC_CTLL_FC_M2P (1 << 20) /* mem-to-periph */
164 #define DWC_CTLL_FC_P2M (2 << 20) /* periph-to-mem */
165 #define DWC_CTLL_FC_P2P (3 << 20) /* periph-to-periph */
166 /* plus 4 transfer types for peripheral-as-flow-controller */
167 #define DWC_CTLL_DMS(n) ((n)<<23) /* dst master select */
168 #define DWC_CTLL_SMS(n) ((n)<<25) /* src master select */
169 #define DWC_CTLL_LLP_D_EN (1 << 27) /* dest block chain */
170 #define DWC_CTLL_LLP_S_EN (1 << 28) /* src block chain */
172 /* Bitfields in CTL_HI */
173 #define DWC_CTLH_DONE 0x00001000
174 #define DWC_CTLH_BLOCK_TS_MASK 0x00000fff
176 /* Bitfields in CFG_LO */
177 #define DWC_CFGL_CH_PRIOR_MASK (0x7 << 5) /* priority mask */
178 #define DWC_CFGL_CH_PRIOR(x) ((x) << 5) /* priority */
179 #define DWC_CFGL_CH_SUSP (1 << 8) /* pause xfer */
180 #define DWC_CFGL_FIFO_EMPTY (1 << 9) /* pause xfer */
181 #define DWC_CFGL_HS_DST (1 << 10) /* handshake w/dst */
182 #define DWC_CFGL_HS_SRC (1 << 11) /* handshake w/src */
183 #define DWC_CFGL_LOCK_CH_XFER (0 << 12) /* scope of LOCK_CH */
184 #define DWC_CFGL_LOCK_CH_BLOCK (1 << 12)
185 #define DWC_CFGL_LOCK_CH_XACT (2 << 12)
186 #define DWC_CFGL_LOCK_BUS_XFER (0 << 14) /* scope of LOCK_BUS */
187 #define DWC_CFGL_LOCK_BUS_BLOCK (1 << 14)
188 #define DWC_CFGL_LOCK_BUS_XACT (2 << 14)
189 #define DWC_CFGL_LOCK_CH (1 << 15) /* channel lockout */
190 #define DWC_CFGL_LOCK_BUS (1 << 16) /* busmaster lockout */
191 #define DWC_CFGL_HS_DST_POL (1 << 18) /* dst handshake active low */
192 #define DWC_CFGL_HS_SRC_POL (1 << 19) /* src handshake active low */
193 #define DWC_CFGL_MAX_BURST(x) ((x) << 20)
194 #define DWC_CFGL_RELOAD_SAR (1 << 30)
195 #define DWC_CFGL_RELOAD_DAR (1 << 31)
197 /* Bitfields in CFG_HI */
198 #define DWC_CFGH_FCMODE (1 << 0)
199 #define DWC_CFGH_FIFO_MODE (1 << 1)
200 #define DWC_CFGH_PROTCTL(x) ((x) << 2)
201 #define DWC_CFGH_DS_UPD_EN (1 << 5)
202 #define DWC_CFGH_SS_UPD_EN (1 << 6)
203 #define DWC_CFGH_SRC_PER(x) ((x) << 7)
204 #define DWC_CFGH_DST_PER(x) ((x) << 11)
206 /* Bitfields in SGR */
207 #define DWC_SGR_SGI(x) ((x) << 0)
208 #define DWC_SGR_SGC(x) ((x) << 20)
210 /* Bitfields in DSR */
211 #define DWC_DSR_DSI(x) ((x) << 0)
212 #define DWC_DSR_DSC(x) ((x) << 20)
214 /* Bitfields in CFG */
215 #define DW_CFG_DMA_EN (1 << 0)
218 DW_DMA_IS_CYCLIC
= 0,
219 DW_DMA_IS_SOFT_LLP
= 1,
220 DW_DMA_IS_PAUSED
= 2,
221 DW_DMA_IS_INITIALIZED
= 3,
225 struct dma_chan chan
;
226 void __iomem
*ch_regs
;
229 enum dma_transfer_direction direction
;
231 /* software emulation of the LLP transfers */
232 struct list_head
*tx_node_active
;
236 /* these other elements are all protected by lock */
238 struct list_head active_list
;
239 struct list_head queue
;
240 struct dw_cyclic_desc
*cdesc
;
242 unsigned int descs_allocated
;
244 /* hardware configuration */
245 unsigned int block_size
;
248 /* custom slave configuration */
249 struct dw_dma_slave dws
;
251 /* configuration passed via .device_config */
252 struct dma_slave_config dma_sconfig
;
255 static inline struct dw_dma_chan_regs __iomem
*
256 __dwc_regs(struct dw_dma_chan
*dwc
)
261 #define channel_readl(dwc, name) \
262 dma_readl_native(&(__dwc_regs(dwc)->name))
263 #define channel_writel(dwc, name, val) \
264 dma_writel_native((val), &(__dwc_regs(dwc)->name))
266 static inline struct dw_dma_chan
*to_dw_dma_chan(struct dma_chan
*chan
)
268 return container_of(chan
, struct dw_dma_chan
, chan
);
272 struct dma_device dma
;
274 struct dma_pool
*desc_pool
;
275 struct tasklet_struct tasklet
;
278 struct dw_dma_chan
*chan
;
283 struct dw_dma_platform_data
*pdata
;
286 static inline struct dw_dma_regs __iomem
*__dw_regs(struct dw_dma
*dw
)
291 #define dma_readl(dw, name) \
292 dma_readl_native(&(__dw_regs(dw)->name))
293 #define dma_writel(dw, name, val) \
294 dma_writel_native((val), &(__dw_regs(dw)->name))
296 #define channel_set_bit(dw, reg, mask) \
297 dma_writel(dw, reg, ((mask) << 8) | (mask))
298 #define channel_clear_bit(dw, reg, mask) \
299 dma_writel(dw, reg, ((mask) << 8) | 0)
301 static inline struct dw_dma
*to_dw_dma(struct dma_device
*ddev
)
303 return container_of(ddev
, struct dw_dma
, dma
);
306 #ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
307 typedef __be32 __dw32
;
309 typedef __le32 __dw32
;
312 /* LLI == Linked List Item; a.k.a. DMA block descriptor */
314 /* values that are not changed by hardware */
317 __dw32 llp
; /* chain to next lli */
319 /* values that may get written back: */
321 /* sstat and dstat can snapshot peripheral register state.
322 * silicon config may discard either or both...
329 /* FIRST values the hardware uses */
332 #ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
333 #define lli_set(d, reg, v) ((d)->lli.reg |= cpu_to_be32(v))
334 #define lli_clear(d, reg, v) ((d)->lli.reg &= ~cpu_to_be32(v))
335 #define lli_read(d, reg) be32_to_cpu((d)->lli.reg)
336 #define lli_write(d, reg, v) ((d)->lli.reg = cpu_to_be32(v))
338 #define lli_set(d, reg, v) ((d)->lli.reg |= cpu_to_le32(v))
339 #define lli_clear(d, reg, v) ((d)->lli.reg &= ~cpu_to_le32(v))
340 #define lli_read(d, reg) le32_to_cpu((d)->lli.reg)
341 #define lli_write(d, reg, v) ((d)->lli.reg = cpu_to_le32(v))
344 /* THEN values for driver housekeeping */
345 struct list_head desc_node
;
346 struct list_head tx_list
;
347 struct dma_async_tx_descriptor txd
;
353 #define to_dw_desc(h) list_entry(h, struct dw_desc, desc_node)
355 static inline struct dw_desc
*
356 txd_to_dw_desc(struct dma_async_tx_descriptor
*txd
)
358 return container_of(txd
, struct dw_desc
, txd
);