/* * 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 /** * 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_MIN_COOKIE 1 #define DMA_MAX_COOKIE INT_MAX #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_PAUSED: transaction is paused * @DMA_ERROR: transaction failed */ enum dma_status { DMA_SUCCESS, DMA_IN_PROGRESS, DMA_PAUSED, DMA_ERROR, }; /** * enum dma_transaction_type - DMA transaction types/indexes * * Note: The DMA_ASYNC_TX capability is not to be set by drivers. It is * automatically set as dma devices are registered. */ enum dma_transaction_type { DMA_MEMCPY, DMA_XOR, DMA_PQ, DMA_XOR_VAL, DMA_PQ_VAL, DMA_MEMSET, DMA_INTERRUPT, DMA_PRIVATE, DMA_ASYNC_TX, 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 - if clear, 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) * @DMA_COMPL_SRC_UNMAP_SINGLE - set to do the source dma-unmapping as single * (if not set, do the source dma-unmapping as page) * @DMA_COMPL_DEST_UNMAP_SINGLE - set to do the destination dma-unmapping as single * (if not set, do the destination dma-unmapping as page) * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as * sources that were the result of a previous operation, in the case of a PQ * operation it continues the calculation with new sources * @DMA_PREP_FENCE - tell the driver that subsequent operations depend * on the result of this operation */ 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_COMPL_SRC_UNMAP_SINGLE = (1 << 4), DMA_COMPL_DEST_UNMAP_SINGLE = (1 << 5), DMA_PREP_PQ_DISABLE_P = (1 << 6), DMA_PREP_PQ_DISABLE_Q = (1 << 7), DMA_PREP_CONTINUE = (1 << 8), DMA_PREP_FENCE = (1 << 9), }; /** * enum dma_ctrl_cmd - DMA operations that can optionally be exercised * on a running channel. * @DMA_TERMINATE_ALL: terminate all ongoing transfers * @DMA_PAUSE: pause ongoing transfers * @DMA_RESUME: resume paused transfer */ enum dma_ctrl_cmd { DMA_TERMINATE_ALL, DMA_PAUSE, DMA_RESUME, }; /** * enum sum_check_bits - bit position of pq_check_flags */ enum sum_check_bits { SUM_CHECK_P = 0, SUM_CHECK_Q = 1, }; /** * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise */ enum sum_check_flags { SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P), SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q), }; /** * 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 * @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 * @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 * @private: private data for certain client-channel associations */ 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 __percpu *local; int client_count; int table_count; void *private; }; /** * struct dma_chan_dev - relate sysfs device node to backing channel device * @chan - driver channel device * @device - sysfs device * @dev_id - parent dma_device dev_id * @idr_ref - reference count to gate release of dma_device dev_id */ struct dma_chan_dev { struct dma_chan *chan; struct device device; int dev_id; atomic_t *idr_ref; }; 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 * @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 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_tx_state - filled in to report the status of * a transfer. * @last: last completed DMA cookie * @used: last issued DMA cookie (i.e. the one in progress) * @residue: the remaining number of bytes left to transmit * on the selected transfer for states DMA_IN_PROGRESS and * DMA_PAUSED if this is implemented in the driver, else 0 */ struct dma_tx_state { dma_cookie_t last; dma_cookie_t used; u32 residue; }; /** * struct dma_device - info on the entity supplying DMA services * @chancnt: how many DMA channels are supported * @privatecnt: how many DMA channels are requested by dma_request_channel * @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 * @max_pq: maximum number of PQ sources and PQ-continue capability * @copy_align: alignment shift for memcpy operations * @xor_align: alignment shift for xor operations * @pq_align: alignment shift for pq operations * @fill_align: alignment shift for memset operations * @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_xor_val: prepares a xor validation operation * @device_prep_dma_pq: prepares a pq operation * @device_prep_dma_pq_val: prepares a pqzero_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_control: manipulate all pending operations on a channel, returns * zero or error code * @device_tx_status: poll for transaction completion, the optional * txstate parameter can be supplied with a pointer to get a * struct with auxilary transfer status information, otherwise the call * will just return a simple status code * @device_issue_pending: push pending transactions to hardware */ struct dma_device { unsigned int chancnt; unsigned int privatecnt; struct list_head channels; struct list_head global_node; dma_cap_mask_t cap_mask; unsigned short max_xor; unsigned short max_pq; u8 copy_align; u8 xor_align; u8 pq_align; u8 fill_align; #define DMA_HAS_PQ_CONTINUE (1 << 15) 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_xor_val)( struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt, size_t len, enum sum_check_flags *result, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_pq)( struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src, unsigned int src_cnt, const unsigned char *scf, size_t len, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)( struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src, unsigned int src_cnt, const unsigned char *scf, size_t len, enum sum_check_flags *pqres, 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); int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg); enum dma_status (*device_tx_status)(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate); void (*device_issue_pending)(struct dma_chan *chan); }; static inline bool dmaengine_check_align(u8 align, size_t off1, size_t off2, size_t len) { size_t mask; if (!align) return true; mask = (1 << align) - 1; if (mask & (off1 | off2 | len)) return false; return true; } static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1, size_t off2, size_t len) { return dmaengine_check_align(dev->copy_align, off1, off2, len); } static inline bool is_dma_xor_aligned(struct dma_device *dev, size_t off1, size_t off2, size_t len) { return dmaengine_check_align(dev->xor_align, off1, off2, len); } static inline bool is_dma_pq_aligned(struct dma_device *dev, size_t off1, size_t off2, size_t len) { return dmaengine_check_align(dev->pq_align, off1, off2, len); } static inline bool is_dma_fill_aligned(struct dma_device *dev, size_t off1, size_t off2, size_t len) { return dmaengine_check_align(dev->fill_align, off1, off2, len); } static inline void dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue) { dma->max_pq = maxpq; if (has_pq_continue) dma->max_pq |= DMA_HAS_PQ_CONTINUE; } static inline bool dmaf_continue(enum dma_ctrl_flags flags) { return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE; } static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags) { enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P; return (flags & mask) == mask; } static inline bool dma_dev_has_pq_continue(struct dma_device *dma) { return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE; } static unsigned short dma_dev_to_maxpq(struct dma_device *dma) { return dma->max_pq & ~DMA_HAS_PQ_CONTINUE; } /* dma_maxpq - reduce maxpq in the face of continued operations * @dma - dma device with PQ capability * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set * * When an engine does not support native continuation we need 3 extra * source slots to reuse P and Q with the following coefficients: * 1/ {00} * P : remove P from Q', but use it as a source for P' * 2/ {01} * Q : use Q to continue Q' calculation * 3/ {00} * Q : subtract Q from P' to cancel (2) * * In the case where P is disabled we only need 1 extra source: * 1/ {01} * Q : use Q to continue Q' calculation */ static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags) { if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags)) return dma_dev_to_maxpq(dma); else if (dmaf_p_disabled_continue(flags)) return dma_dev_to_maxpq(dma) - 1; else if (dmaf_continue(flags)) return dma_dev_to_maxpq(dma) - 3; BUG(); } /* --- public DMA engine API --- */ #ifdef CONFIG_DMA_ENGINE void dmaengine_get(void); void dmaengine_put(void); #else static inline void dmaengine_get(void) { } static inline void dmaengine_put(void) { } #endif #ifdef CONFIG_NET_DMA #define net_dmaengine_get() dmaengine_get() #define net_dmaengine_put() dmaengine_put() #else static inline void net_dmaengine_get(void) { } static inline void net_dmaengine_put(void) { } #endif #ifdef CONFIG_ASYNC_TX_DMA #define async_dmaengine_get() dmaengine_get() #define async_dmaengine_put() dmaengine_put() #ifdef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH #define async_dma_find_channel(type) dma_find_channel(DMA_ASYNC_TX) #else #define async_dma_find_channel(type) dma_find_channel(type) #endif /* CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH */ #else static inline void async_dmaengine_get(void) { } static inline void async_dmaengine_put(void) { } static inline struct dma_chan * async_dma_find_channel(enum dma_transaction_type type) { return NULL; } #endif /* CONFIG_ASYNC_TX_DMA */ 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 void async_tx_clear_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_clear(tx, mask) __dma_cap_clear((tx), &(mask)) static inline void __dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) { clear_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) { struct dma_tx_state state; enum dma_status status; status = chan->device->device_tx_status(chan, cookie, &state); if (last) *last = state.last; if (used) *used = state.used; return status; } #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; } static inline void dma_set_tx_state(struct dma_tx_state *st, dma_cookie_t last, dma_cookie_t used, u32 residue) { if (st) { st->last = last; st->used = used; st->residue = residue; } } 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); void dma_issue_pending_all(void); #else static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) { return DMA_SUCCESS; } static inline void dma_issue_pending_all(void) { do { } while (0); } #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); #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 */