arch/arm/plat-stmp3xxx/include/mach/dma.h

   1 /*
   2  * Freescale STMP37XX/STMP378X DMA helper interface
   3  *
   4  * Embedded Alley Solutions, Inc <source@embeddedalley.com>
   5  *
   6  * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
   7  * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
   8  */
   9
  10 /*
  11  * The code contained herein is licensed under the GNU General Public
  12  * License. You may obtain a copy of the GNU General Public License
  13  * Version 2 or later at the following locations:
  14  *
  15  * http://www.opensource.org/licenses/gpl-license.html
  16  * http://www.gnu.org/copyleft/gpl.html
  17  */
  18 #ifndef __ASM_PLAT_STMP3XXX_DMA_H
  19 #define __ASM_PLAT_STMP3XXX_DMA_H
  20
  21 #include <linux/platform_device.h>
  22 #include <linux/dmapool.h>
  23
  24 #if !defined(MAX_PIO_WORDS)
  25 #define MAX_PIO_WORDS   (15)
  26 #endif
  27
  28 #define STMP3XXX_BUS_APBH               0
  29 #define STMP3XXX_BUS_APBX               1
  30 #define STMP3XXX_DMA_MAX_CHANNEL        16
  31 #define STMP3XXX_DMA_BUS(dma)           ((dma) / 16)
  32 #define STMP3XXX_DMA_CHANNEL(dma)       ((dma) % 16)
  33 #define STMP3XXX_DMA(channel, bus)      ((bus) * 16 + (channel))
  34 #define MAX_DMA_ADDRESS                 0xffffffff
  35 #define MAX_DMA_CHANNELS                32
  36
  37 struct stmp3xxx_dma_command {
  38         u32 next;
  39         u32 cmd;
  40         union {
  41                 u32 buf_ptr;
  42                 u32 alternate;
  43         };
  44         u32 pio_words[MAX_PIO_WORDS];
  45 };
  46
  47 struct stmp3xxx_dma_descriptor {
  48         struct stmp3xxx_dma_command *command;
  49         dma_addr_t handle;
  50
  51         /* The virtual address of the buffer pointer */
  52         void *virtual_buf_ptr;
  53         /* The next descriptor in a the DMA chain (optional) */
  54         struct stmp3xxx_dma_descriptor *next_descr;
  55 };
  56
  57 struct stmp37xx_circ_dma_chain {
  58         unsigned total_count;
  59         struct stmp3xxx_dma_descriptor *chain;
  60
  61         unsigned free_index;
  62         unsigned free_count;
  63         unsigned active_index;
  64         unsigned active_count;
  65         unsigned cooked_index;
  66         unsigned cooked_count;
  67
  68         int bus;
  69         unsigned channel;
  70 };
  71
  72 static inline struct stmp3xxx_dma_descriptor
  73     *stmp3xxx_dma_circ_get_free_head(struct stmp37xx_circ_dma_chain *chain)
  74 {
  75         return &(chain->chain[chain->free_index]);
  76 }
  77
  78 static inline struct stmp3xxx_dma_descriptor
  79     *stmp3xxx_dma_circ_get_cooked_head(struct stmp37xx_circ_dma_chain *chain)
  80 {
  81         return &(chain->chain[chain->cooked_index]);
  82 }
  83
  84 int stmp3xxx_dma_request(int ch, struct device *dev, const char *name);
  85 int stmp3xxx_dma_release(int ch);
  86 int stmp3xxx_dma_allocate_command(int ch,
  87                                   struct stmp3xxx_dma_descriptor *descriptor);
  88 int stmp3xxx_dma_free_command(int ch,
  89                               struct stmp3xxx_dma_descriptor *descriptor);
  90 void stmp3xxx_dma_continue(int channel, u32 semaphore);
  91 void stmp3xxx_dma_go(int ch, struct stmp3xxx_dma_descriptor *head,
  92                      u32 semaphore);
  93 int stmp3xxx_dma_running(int ch);
  94 int stmp3xxx_dma_make_chain(int ch, struct stmp37xx_circ_dma_chain *chain,
  95                             struct stmp3xxx_dma_descriptor descriptors[],
  96                             unsigned items);
  97 void stmp3xxx_dma_free_chain(struct stmp37xx_circ_dma_chain *chain);
  98 void stmp37xx_circ_clear_chain(struct stmp37xx_circ_dma_chain *chain);
  99 void stmp37xx_circ_advance_free(struct stmp37xx_circ_dma_chain *chain,
 100                 unsigned count);
 101 void stmp37xx_circ_advance_active(struct stmp37xx_circ_dma_chain *chain,
 102                 unsigned count);
 103 unsigned stmp37xx_circ_advance_cooked(struct stmp37xx_circ_dma_chain *chain);
 104 int stmp3xxx_dma_read_semaphore(int ch);
 105 void stmp3xxx_dma_init(void);
 106 void stmp3xxx_dma_set_alt_target(int ch, int target);
 107 void stmp3xxx_dma_suspend(void);
 108 void stmp3xxx_dma_resume(void);
 109
 110 /*
 111  * STMP37xx and STMP378x have different DMA control
 112  * registers layout
 113  */
 114
 115 void stmp3xxx_arch_dma_freeze(int ch);
 116 void stmp3xxx_arch_dma_unfreeze(int ch);
 117 void stmp3xxx_arch_dma_reset_channel(int ch);
 118 void stmp3xxx_arch_dma_enable_interrupt(int ch);
 119 void stmp3xxx_arch_dma_clear_interrupt(int ch);
 120 int stmp3xxx_arch_dma_is_interrupt(int ch);
 121
 122 static inline void stmp3xxx_dma_reset_channel(int ch)
 123 {
 124         stmp3xxx_arch_dma_reset_channel(ch);
 125 }
 126
 127
 128 static inline void stmp3xxx_dma_freeze(int ch)
 129 {
 130         stmp3xxx_arch_dma_freeze(ch);
 131 }
 132
 133 static inline void stmp3xxx_dma_unfreeze(int ch)
 134 {
 135         stmp3xxx_arch_dma_unfreeze(ch);
 136 }
 137
 138 static inline void stmp3xxx_dma_enable_interrupt(int ch)
 139 {
 140         stmp3xxx_arch_dma_enable_interrupt(ch);
 141 }
 142
 143 static inline void stmp3xxx_dma_clear_interrupt(int ch)
 144 {
 145         stmp3xxx_arch_dma_clear_interrupt(ch);
 146 }
 147
 148 static inline int stmp3xxx_dma_is_interrupt(int ch)
 149 {
 150         return stmp3xxx_arch_dma_is_interrupt(ch);
 151 }
 152
 153 #endif /* __ASM_PLAT_STMP3XXX_DMA_H */