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