LXR linux/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
  37struct 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
  47struct 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
  57struct 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
  72static 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
  78static 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
  84int stmp3xxx_dma_request(int ch, struct device *dev, const char *name);
  85int stmp3xxx_dma_release(int ch);
  86int stmp3xxx_dma_allocate_command(int ch,
  87                                  struct stmp3xxx_dma_descriptor *descriptor);
  88int stmp3xxx_dma_free_command(int ch,
  89                              struct stmp3xxx_dma_descriptor *descriptor);
  90void stmp3xxx_dma_continue(int channel, u32 semaphore);
  91void stmp3xxx_dma_go(int ch, struct stmp3xxx_dma_descriptor *head,
  92                     u32 semaphore);
  93int stmp3xxx_dma_running(int ch);
  94int stmp3xxx_dma_make_chain(int ch, struct stmp37xx_circ_dma_chain *chain,
  95                            struct stmp3xxx_dma_descriptor descriptors[],
  96                            unsigned items);
  97void stmp3xxx_dma_free_chain(struct stmp37xx_circ_dma_chain *chain);
  98void stmp37xx_circ_clear_chain(struct stmp37xx_circ_dma_chain *chain);
  99void stmp37xx_circ_advance_free(struct stmp37xx_circ_dma_chain *chain,
 100                unsigned count);
 101void stmp37xx_circ_advance_active(struct stmp37xx_circ_dma_chain *chain,
 102                unsigned count);
 103unsigned stmp37xx_circ_advance_cooked(struct stmp37xx_circ_dma_chain *chain);
 104int stmp3xxx_dma_read_semaphore(int ch);
 105void stmp3xxx_dma_init(void);
 106void stmp3xxx_dma_set_alt_target(int ch, int target);
 107void stmp3xxx_dma_suspend(void);
 108void stmp3xxx_dma_resume(void);
 109
 110/*
 111 * STMP37xx and STMP378x have different DMA control
 112 * registers layout
 113 */
 114
 115void stmp3xxx_arch_dma_freeze(int ch);
 116void stmp3xxx_arch_dma_unfreeze(int ch);
 117void stmp3xxx_arch_dma_reset_channel(int ch);
 118void stmp3xxx_arch_dma_enable_interrupt(int ch);
 119void stmp3xxx_arch_dma_clear_interrupt(int ch);
 120int stmp3xxx_arch_dma_is_interrupt(int ch);
 121
 122static inline void stmp3xxx_dma_reset_channel(int ch)
 123{
 124        stmp3xxx_arch_dma_reset_channel(ch);
 125}
 126
 127
 128static inline void stmp3xxx_dma_freeze(int ch)
 129{
 130        stmp3xxx_arch_dma_freeze(ch);
 131}
 132
 133static inline void stmp3xxx_dma_unfreeze(int ch)
 134{
 135        stmp3xxx_arch_dma_unfreeze(ch);
 136}
 137
 138static inline void stmp3xxx_dma_enable_interrupt(int ch)
 139{
 140        stmp3xxx_arch_dma_enable_interrupt(ch);
 141}
 142
 143static inline void stmp3xxx_dma_clear_interrupt(int ch)
 144{
 145        stmp3xxx_arch_dma_clear_interrupt(ch);
 146}
 147
 148static 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 */
 154