/* * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * The full GNU General Public License is included in this distribution in the * file called COPYING. */ #ifndef DMAENGINE_H #define DMAENGINE_H #include #include #include #include #include #include /** * typedef dma_cookie_t - an opaque DMA cookie * * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code */ typedef s32 dma_cookie_t; #define dma_submit_error(cookie) ((cookie) < 0 ? 1 : 0) /** * enum dma_status - DMA transaction status * @DMA_SUCCESS: transaction completed successfully * @DMA_IN_PROGRESS: transaction not yet processed * @DMA_ERROR: transaction failed */ enum dma_status { DMA_SUCCESS, DMA_IN_PROGRESS, DMA_ERROR, }; /** * enum dma_transaction_type - DMA transaction types/indexes */ enum dma_transaction_type { DMA_MEMCPY, DMA_XOR, DMA_PQ_XOR, DMA_DUAL_XOR, DMA_PQ_UPDATE, DMA_ZERO_SUM, DMA_PQ_ZERO_SUM, DMA_MEMSET, DMA_MEMCPY_CRC32C, DMA_INTERRUPT, DMA_PRIVATE, DMA_SLAVE, }; /* last transaction type for creation of the capabilities mask */ #define DMA_TX_TYPE_END (DMA_SLAVE + 1) /** * enum dma_ctrl_flags - DMA flags to augment operation preparation, * control completion, and communicate status. * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of * this transaction * @DMA_CTRL_ACK - the descriptor cannot be reused until the client * acknowledges receipt, i.e. has has a chance to establish any * dependency chains * @DMA_COMPL_SKIP_SRC_UNMAP - set to disable dma-unmapping the source buffer(s) * @DMA_COMPL_SKIP_DEST_UNMAP - set to disable dma-unmapping the destination(s) */ enum dma_ctrl_flags { DMA_PREP_INTERRUPT = (1 << 0), DMA_CTRL_ACK = (1 << 1), DMA_COMPL_SKIP_SRC_UNMAP = (1 << 2), DMA_COMPL_SKIP_DEST_UNMAP = (1 << 3), }; /** * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t. * See linux/cpumask.h */ typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t; /** * struct dma_chan_percpu - the per-CPU part of struct dma_chan * @refcount: local_t used for open-coded "bigref" counting * @memcpy_count: transaction counter * @bytes_transferred: byte counter */ struct dma_chan_percpu { /* stats */ unsigned long memcpy_count; unsigned long bytes_transferred; }; /** * struct dma_chan - devices supply DMA channels, clients use them * @device: ptr to the dma device who supplies this channel, always !%NULL * @cookie: last cookie value returned to client * @chan_id: channel ID for sysfs * @dev: class device for sysfs * @refcount: kref, used in "bigref" slow-mode * @slow_ref: indicates that the DMA channel is free * @rcu: the DMA channel's RCU head * @device_node: used to add this to the device chan list * @local: per-cpu pointer to a struct dma_chan_percpu * @client-count: how many clients are using this channel * @table_count: number of appearances in the mem-to-mem allocation table */ struct dma_chan { struct dma_device *device; dma_cookie_t cookie; /* sysfs */ int chan_id; struct dma_chan_dev *dev; struct list_head device_node; struct dma_chan_percpu *local; int client_count; int table_count; }; /** * struct dma_chan_dev - relate sysfs device node to backing channel device * @chan - driver channel device * @device - sysfs device */ struct dma_chan_dev { struct dma_chan *chan; struct device device; }; static inline const char *dma_chan_name(struct dma_chan *chan) { return dev_name(&chan->dev->device); } void dma_chan_cleanup(struct kref *kref); /** * typedef dma_filter_fn - callback filter for dma_request_channel * @chan: channel to be reviewed * @filter_param: opaque parameter passed through dma_request_channel * * When this optional parameter is specified in a call to dma_request_channel a * suitable channel is passed to this routine for further dispositioning before * being returned. Where 'suitable' indicates a non-busy channel that * satisfies the given capability mask. It returns 'true' to indicate that the * channel is suitable. */ typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); typedef void (*dma_async_tx_callback)(void *dma_async_param); /** * struct dma_async_tx_descriptor - async transaction descriptor * ---dma generic offload fields--- * @cookie: tracking cookie for this transaction, set to -EBUSY if * this tx is sitting on a dependency list * @flags: flags to augment operation preparation, control completion, and * communicate status * @phys: physical address of the descriptor * @tx_list: driver common field for operations that require multiple * descriptors * @chan: target channel for this operation * @tx_submit: set the prepared descriptor(s) to be executed by the engine * @callback: routine to call after this operation is complete * @callback_param: general parameter to pass to the callback routine * ---async_tx api specific fields--- * @next: at completion submit this descriptor * @parent: pointer to the next level up in the dependency chain * @lock: protect the parent and next pointers */ struct dma_async_tx_descriptor { dma_cookie_t cookie; enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */ dma_addr_t phys; struct list_head tx_list; struct dma_chan *chan; dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx); dma_async_tx_callback callback; void *callback_param; struct dma_async_tx_descriptor *next; struct dma_async_tx_descriptor *parent; spinlock_t lock; }; /** * struct dma_device - info on the entity supplying DMA services * @chancnt: how many DMA channels are supported * @channels: the list of struct dma_chan * @global_node: list_head for global dma_device_list * @cap_mask: one or more dma_capability flags * @max_xor: maximum number of xor sources, 0 if no capability * @refcount: reference count * @done: IO completion struct * @dev_id: unique device ID * @dev: struct device reference for dma mapping api * @device_alloc_chan_resources: allocate resources and return the * number of allocated descriptors * @device_free_chan_resources: release DMA channel's resources * @device_prep_dma_memcpy: prepares a memcpy operation * @device_prep_dma_xor: prepares a xor operation * @device_prep_dma_zero_sum: prepares a zero_sum operation * @device_prep_dma_memset: prepares a memset operation * @device_prep_dma_interrupt: prepares an end of chain interrupt operation * @device_prep_slave_sg: prepares a slave dma operation * @device_terminate_all: terminate all pending operations * @device_issue_pending: push pending transactions to hardware */ struct dma_device { unsigned int chancnt; struct list_head channels; struct list_head global_node; dma_cap_mask_t cap_mask; int max_xor; int dev_id; struct device *dev; int (*device_alloc_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)( struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_xor)( struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, unsigned int src_cnt, size_t len, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_zero_sum)( struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt, size_t len, u32 *result, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_memset)( struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)( struct dma_chan *chan, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_slave_sg)( struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_data_direction direction, unsigned long flags); void (*device_terminate_all)(struct dma_chan *chan); enum dma_status (*device_is_tx_complete)(struct dma_chan *chan, dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used); void (*device_issue_pending)(struct dma_chan *chan); }; /* --- public DMA engine API --- */ void dmaengine_get(void); void dmaengine_put(void); dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest, void *src, size_t len); dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page, unsigned int offset, void *kdata, size_t len); dma_cookie_t dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg, unsigned int dest_off, struct page *src_pg, unsigned int src_off, size_t len); void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx, struct dma_chan *chan); static inline void async_tx_ack(struct dma_async_tx_descriptor *tx) { tx->flags |= DMA_CTRL_ACK; } static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx) { return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK; } #define first_dma_cap(mask) __first_dma_cap(&(mask)) static inline int __first_dma_cap(const dma_cap_mask_t *srcp) { return min_t(int, DMA_TX_TYPE_END, find_first_bit(srcp->bits, DMA_TX_TYPE_END)); } #define next_dma_cap(n, mask) __next_dma_cap((n), &(mask)) static inline int __next_dma_cap(int n, const dma_cap_mask_t *srcp) { return min_t(int, DMA_TX_TYPE_END, find_next_bit(srcp->bits, DMA_TX_TYPE_END, n+1)); } #define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask)) static inline void __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) { set_bit(tx_type, dstp->bits); } #define dma_cap_zero(mask) __dma_cap_zero(&(mask)) static inline void __dma_cap_zero(dma_cap_mask_t *dstp) { bitmap_zero(dstp->bits, DMA_TX_TYPE_END); } #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask)) static inline int __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp) { return test_bit(tx_type, srcp->bits); } #define for_each_dma_cap_mask(cap, mask) \ for ((cap) = first_dma_cap(mask); \ (cap) < DMA_TX_TYPE_END; \ (cap) = next_dma_cap((cap), (mask))) /** * dma_async_issue_pending - flush pending transactions to HW * @chan: target DMA channel * * This allows drivers to push copies to HW in batches, * reducing MMIO writes where possible. */ static inline void dma_async_issue_pending(struct dma_chan *chan) { chan->device->device_issue_pending(chan); } #define dma_async_memcpy_issue_pending(chan) dma_async_issue_pending(chan) /** * dma_async_is_tx_complete - poll for transaction completion * @chan: DMA channel * @cookie: transaction identifier to check status of * @last: returns last completed cookie, can be NULL * @used: returns last issued cookie, can be NULL * * If @last and @used are passed in, upon return they reflect the driver * internal state and can be used with dma_async_is_complete() to check * the status of multiple cookies without re-checking hardware state. */ static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan, dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used) { return chan->device->device_is_tx_complete(chan, cookie, last, used); } #define dma_async_memcpy_complete(chan, cookie, last, used)\ dma_async_is_tx_complete(chan, cookie, last, used) /** * dma_async_is_complete - test a cookie against chan state * @cookie: transaction identifier to test status of * @last_complete: last know completed transaction * @last_used: last cookie value handed out * * dma_async_is_complete() is used in dma_async_memcpy_complete() * the test logic is separated for lightweight testing of multiple cookies */ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie, dma_cookie_t last_complete, dma_cookie_t last_used) { if (last_complete <= last_used) { if ((cookie <= last_complete) || (cookie > last_used)) return DMA_SUCCESS; } else { if ((cookie <= last_complete) && (cookie > last_used)) return DMA_SUCCESS; } return DMA_IN_PROGRESS; } enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie); #ifdef CONFIG_DMA_ENGINE enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx); #else static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) { return DMA_SUCCESS; } #endif /* --- DMA device --- */ int dma_async_device_register(struct dma_device *device); void dma_async_device_unregister(struct dma_device *device); void dma_run_dependencies(struct dma_async_tx_descriptor *tx); struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type); void dma_issue_pending_all(void); #define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y) struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param); void dma_release_channel(struct dma_chan *chan); /* --- Helper iov-locking functions --- */ struct dma_page_list { char __user *base_address; int nr_pages; struct page **pages; }; struct dma_pinned_list { int nr_iovecs; struct dma_page_list page_list[0]; }; struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len); void dma_unpin_iovec_pages(struct dma_pinned_list* pinned_list); dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov, struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len); dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov, struct dma_pinned_list *pinned_list, struct page *page, unsigned int offset, size_t len); #endif /* DMAENGINE_H */