arch/arm/mach-s3c2410/include/mach/dma.h

   1 /* arch/arm/mach-s3c2410/include/mach/dma.h
   2  *
   3  * Copyright (C) 2003-2006 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * Samsung S3C24XX DMA support
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11 */
  12
  13 #ifndef __ASM_ARCH_DMA_H
  14 #define __ASM_ARCH_DMA_H __FILE__
  15
  16 #include <linux/device.h>
  17
  18 #define MAX_DMA_TRANSFER_SIZE   0x100000 /* Data Unit is half word  */
  19
  20 /* We use `virtual` dma channels to hide the fact we have only a limited
  21  * number of DMA channels, and not of all of them (dependent on the device)
  22  * can be attached to any DMA source. We therefore let the DMA core handle
  23  * the allocation of hardware channels to clients.
  24 */
  25
  26 enum dma_ch {
  27         DMACH_XD0,
  28         DMACH_XD1,
  29         DMACH_SDI,
  30         DMACH_SPI0,
  31         DMACH_SPI1,
  32         DMACH_UART0,
  33         DMACH_UART1,
  34         DMACH_UART2,
  35         DMACH_TIMER,
  36         DMACH_I2S_IN,
  37         DMACH_I2S_OUT,
  38         DMACH_PCM_IN,
  39         DMACH_PCM_OUT,
  40         DMACH_MIC_IN,
  41         DMACH_USB_EP1,
  42         DMACH_USB_EP2,
  43         DMACH_USB_EP3,
  44         DMACH_USB_EP4,
  45         DMACH_UART0_SRC2,       /* s3c2412 second uart sources */
  46         DMACH_UART1_SRC2,
  47         DMACH_UART2_SRC2,
  48         DMACH_UART3,            /* s3c2443 has extra uart */
  49         DMACH_UART3_SRC2,
  50         DMACH_MAX,              /* the end entry */
  51 };
  52
  53 static inline bool samsung_dma_has_circular(void)
  54 {
  55         return false;
  56 }
  57
  58 static inline bool samsung_dma_is_dmadev(void)
  59 {
  60         return false;
  61 }
  62
  63 #include <plat/dma.h>
  64
  65 #define DMACH_LOW_LEVEL (1<<28) /* use this to specifiy hardware ch no */
  66
  67 /* we have 4 dma channels */
  68 #if !defined(CONFIG_CPU_S3C2443) && !defined(CONFIG_CPU_S3C2416)
  69 #define S3C_DMA_CHANNELS                (4)
  70 #else
  71 #define S3C_DMA_CHANNELS                (6)
  72 #endif
  73
  74 /* types */
  75
  76 enum s3c2410_dma_state {
  77         S3C2410_DMA_IDLE,
  78         S3C2410_DMA_RUNNING,
  79         S3C2410_DMA_PAUSED
  80 };
  81
  82 /* enum s3c2410_dma_loadst
  83  *
  84  * This represents the state of the DMA engine, wrt to the loaded / running
  85  * transfers. Since we don't have any way of knowing exactly the state of
  86  * the DMA transfers, we need to know the state to make decisions on wether
  87  * we can
  88  *
  89  * S3C2410_DMA_NONE
  90  *
  91  * There are no buffers loaded (the channel should be inactive)
  92  *
  93  * S3C2410_DMA_1LOADED
  94  *
  95  * There is one buffer loaded, however it has not been confirmed to be
  96  * loaded by the DMA engine. This may be because the channel is not
  97  * yet running, or the DMA driver decided that it was too costly to
  98  * sit and wait for it to happen.
  99  *
 100  * S3C2410_DMA_1RUNNING
 101  *
 102  * The buffer has been confirmed running, and not finisged
 103  *
 104  * S3C2410_DMA_1LOADED_1RUNNING
 105  *
 106  * There is a buffer waiting to be loaded by the DMA engine, and one
 107  * currently running.
 108 */
 109
 110 enum s3c2410_dma_loadst {
 111         S3C2410_DMALOAD_NONE,
 112         S3C2410_DMALOAD_1LOADED,
 113         S3C2410_DMALOAD_1RUNNING,
 114         S3C2410_DMALOAD_1LOADED_1RUNNING,
 115 };
 116
 117
 118 /* flags */
 119
 120 #define S3C2410_DMAF_SLOW         (1<<0)   /* slow, so don't worry about
 121                                             * waiting for reloads */
 122 #define S3C2410_DMAF_AUTOSTART    (1<<1)   /* auto-start if buffer queued */
 123
 124 #define S3C2410_DMAF_CIRCULAR   (1 << 2)        /* no circular dma support */
 125
 126 /* dma buffer */
 127
 128 struct s3c2410_dma_buf;
 129
 130 /* s3c2410_dma_buf
 131  *
 132  * internally used buffer structure to describe a queued or running
 133  * buffer.
 134 */
 135
 136 struct s3c2410_dma_buf {
 137         struct s3c2410_dma_buf  *next;
 138         int                      magic;         /* magic */
 139         int                      size;          /* buffer size in bytes */
 140         dma_addr_t               data;          /* start of DMA data */
 141         dma_addr_t               ptr;           /* where the DMA got to [1] */
 142         void                    *id;            /* client's id */
 143 };
 144
 145 /* [1] is this updated for both recv/send modes? */
 146
 147 struct s3c2410_dma_stats {
 148         unsigned long           loads;
 149         unsigned long           timeout_longest;
 150         unsigned long           timeout_shortest;
 151         unsigned long           timeout_avg;
 152         unsigned long           timeout_failed;
 153 };
 154
 155 struct s3c2410_dma_map;
 156
 157 /* struct s3c2410_dma_chan
 158  *
 159  * full state information for each DMA channel
 160 */
 161
 162 struct s3c2410_dma_chan {
 163         /* channel state flags and information */
 164         unsigned char            number;      /* number of this dma channel */
 165         unsigned char            in_use;      /* channel allocated */
 166         unsigned char            irq_claimed; /* irq claimed for channel */
 167         unsigned char            irq_enabled; /* irq enabled for channel */
 168         unsigned char            xfer_unit;   /* size of an transfer */
 169
 170         /* channel state */
 171
 172         enum s3c2410_dma_state   state;
 173         enum s3c2410_dma_loadst  load_state;
 174         struct s3c2410_dma_client *client;
 175
 176         /* channel configuration */
 177         enum dma_data_direction  source;
 178         enum dma_ch              req_ch;
 179         unsigned long            dev_addr;
 180         unsigned long            load_timeout;
 181         unsigned int             flags;         /* channel flags */
 182
 183         struct s3c24xx_dma_map  *map;           /* channel hw maps */
 184
 185         /* channel's hardware position and configuration */
 186         void __iomem            *regs;          /* channels registers */
 187         void __iomem            *addr_reg;      /* data address register */
 188         unsigned int             irq;           /* channel irq */
 189         unsigned long            dcon;          /* default value of DCON */
 190
 191         /* driver handles */
 192         s3c2410_dma_cbfn_t       callback_fn;   /* buffer done callback */
 193         s3c2410_dma_opfn_t       op_fn;         /* channel op callback */
 194
 195         /* stats gathering */
 196         struct s3c2410_dma_stats *stats;
 197         struct s3c2410_dma_stats  stats_store;
 198
 199         /* buffer list and information */
 200         struct s3c2410_dma_buf  *curr;          /* current dma buffer */
 201         struct s3c2410_dma_buf  *next;          /* next buffer to load */
 202         struct s3c2410_dma_buf  *end;           /* end of queue */
 203
 204         /* system device */
 205         struct device   dev;
 206 };
 207
 208 typedef unsigned long dma_device_t;
 209
 210 #endif /* __ASM_ARCH_DMA_H */