alistair23-linux/include/linux/dmaengine.h
Geert Uytterhoeven 7dfffb9541 dmaengine: Stricter legacy checking in dma_request_slave_channel_compat()
dma_request_slave_channel_compat() is meant for drivers that support
both DT and legacy platform device based probing: if DT channel DMA
setup fails, it will fall back to platform data based DMA channel setup,
using hardcoded DMA channel IDs and a filter function.

However, if the DTS doesn't provide a "dmas" property for the device,
the fallback is also used. If the legacy filter function is not
hardcoded in the DMA slave driver, but comes from platform data, it will
be NULL. Then dma_request_slave_channel_compat() will succeed
incorrectly, and return a DMA channel, as a NULL legacy filter function
actually means "all channels are OK", not "do not match".

Later, when trying to use that DMA channel, it will fail with:

    rcar-dmac e6700000.dma-controller: rcar_dmac_prep_slave_sg: bad parameter: len=1, id=-22

To fix this, ensure that both the filter function and the DMA channel ID
are not NULL before using the legacy fallback.

Note that some DMA slave drivers can handle this failure, and will fall
back to PIO.

See also commit 056f6c8702 ("dmaengine: shdma: Make dummy
shdma_chan_filter() always return false"), which fixed the same issue
for the case where shdma_chan_filter() is hardcoded in a DMA slave
driver.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-20 12:01:03 +05:30

1246 lines
40 KiB
C

/*
* 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.
*
* The full GNU General Public License is included in this distribution in the
* file called COPYING.
*/
#ifndef LINUX_DMAENGINE_H
#define LINUX_DMAENGINE_H
#include <linux/device.h>
#include <linux/err.h>
#include <linux/uio.h>
#include <linux/bug.h>
#include <linux/scatterlist.h>
#include <linux/bitmap.h>
#include <linux/types.h>
#include <asm/page.h>
/**
* 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
static inline int dma_submit_error(dma_cookie_t cookie)
{
return cookie < 0 ? cookie : 0;
}
/**
* enum dma_status - DMA transaction status
* @DMA_COMPLETE: transaction completed
* @DMA_IN_PROGRESS: transaction not yet processed
* @DMA_PAUSED: transaction is paused
* @DMA_ERROR: transaction failed
*/
enum dma_status {
DMA_COMPLETE,
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_MEMSET_SG,
DMA_INTERRUPT,
DMA_SG,
DMA_PRIVATE,
DMA_ASYNC_TX,
DMA_SLAVE,
DMA_CYCLIC,
DMA_INTERLEAVE,
/* last transaction type for creation of the capabilities mask */
DMA_TX_TYPE_END,
};
/**
* enum dma_transfer_direction - dma transfer mode and direction indicator
* @DMA_MEM_TO_MEM: Async/Memcpy mode
* @DMA_MEM_TO_DEV: Slave mode & From Memory to Device
* @DMA_DEV_TO_MEM: Slave mode & From Device to Memory
* @DMA_DEV_TO_DEV: Slave mode & From Device to Device
*/
enum dma_transfer_direction {
DMA_MEM_TO_MEM,
DMA_MEM_TO_DEV,
DMA_DEV_TO_MEM,
DMA_DEV_TO_DEV,
DMA_TRANS_NONE,
};
/**
* Interleaved Transfer Request
* ----------------------------
* A chunk is collection of contiguous bytes to be transfered.
* The gap(in bytes) between two chunks is called inter-chunk-gap(ICG).
* ICGs may or maynot change between chunks.
* A FRAME is the smallest series of contiguous {chunk,icg} pairs,
* that when repeated an integral number of times, specifies the transfer.
* A transfer template is specification of a Frame, the number of times
* it is to be repeated and other per-transfer attributes.
*
* Practically, a client driver would have ready a template for each
* type of transfer it is going to need during its lifetime and
* set only 'src_start' and 'dst_start' before submitting the requests.
*
*
* | Frame-1 | Frame-2 | ~ | Frame-'numf' |
* |====....==.===...=...|====....==.===...=...| ~ |====....==.===...=...|
*
* == Chunk size
* ... ICG
*/
/**
* struct data_chunk - Element of scatter-gather list that makes a frame.
* @size: Number of bytes to read from source.
* size_dst := fn(op, size_src), so doesn't mean much for destination.
* @icg: Number of bytes to jump after last src/dst address of this
* chunk and before first src/dst address for next chunk.
* Ignored for dst(assumed 0), if dst_inc is true and dst_sgl is false.
* Ignored for src(assumed 0), if src_inc is true and src_sgl is false.
* @dst_icg: Number of bytes to jump after last dst address of this
* chunk and before the first dst address for next chunk.
* Ignored if dst_inc is true and dst_sgl is false.
* @src_icg: Number of bytes to jump after last src address of this
* chunk and before the first src address for next chunk.
* Ignored if src_inc is true and src_sgl is false.
*/
struct data_chunk {
size_t size;
size_t icg;
size_t dst_icg;
size_t src_icg;
};
/**
* struct dma_interleaved_template - Template to convey DMAC the transfer pattern
* and attributes.
* @src_start: Bus address of source for the first chunk.
* @dst_start: Bus address of destination for the first chunk.
* @dir: Specifies the type of Source and Destination.
* @src_inc: If the source address increments after reading from it.
* @dst_inc: If the destination address increments after writing to it.
* @src_sgl: If the 'icg' of sgl[] applies to Source (scattered read).
* Otherwise, source is read contiguously (icg ignored).
* Ignored if src_inc is false.
* @dst_sgl: If the 'icg' of sgl[] applies to Destination (scattered write).
* Otherwise, destination is filled contiguously (icg ignored).
* Ignored if dst_inc is false.
* @numf: Number of frames in this template.
* @frame_size: Number of chunks in a frame i.e, size of sgl[].
* @sgl: Array of {chunk,icg} pairs that make up a frame.
*/
struct dma_interleaved_template {
dma_addr_t src_start;
dma_addr_t dst_start;
enum dma_transfer_direction dir;
bool src_inc;
bool dst_inc;
bool src_sgl;
bool dst_sgl;
size_t numf;
size_t frame_size;
struct data_chunk sgl[0];
};
/**
* 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_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
* @DMA_CTRL_REUSE: client can reuse the descriptor and submit again till
* cleared or freed
*/
enum dma_ctrl_flags {
DMA_PREP_INTERRUPT = (1 << 0),
DMA_CTRL_ACK = (1 << 1),
DMA_PREP_PQ_DISABLE_P = (1 << 2),
DMA_PREP_PQ_DISABLE_Q = (1 << 3),
DMA_PREP_CONTINUE = (1 << 4),
DMA_PREP_FENCE = (1 << 5),
DMA_CTRL_REUSE = (1 << 6),
};
/**
* 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_router - DMA router structure
* @dev: pointer to the DMA router device
* @route_free: function to be called when the route can be disconnected
*/
struct dma_router {
struct device *dev;
void (*route_free)(struct device *dev, void *route_data);
};
/**
* 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
* @completed_cookie: last completed cookie for this channel
* @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
* @router: pointer to the DMA router structure
* @route_data: channel specific data for the router
* @private: private data for certain client-channel associations
*/
struct dma_chan {
struct dma_device *device;
dma_cookie_t cookie;
dma_cookie_t completed_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;
/* DMA router */
struct dma_router *router;
void *route_data;
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;
};
/**
* enum dma_slave_buswidth - defines bus width of the DMA slave
* device, source or target buses
*/
enum dma_slave_buswidth {
DMA_SLAVE_BUSWIDTH_UNDEFINED = 0,
DMA_SLAVE_BUSWIDTH_1_BYTE = 1,
DMA_SLAVE_BUSWIDTH_2_BYTES = 2,
DMA_SLAVE_BUSWIDTH_3_BYTES = 3,
DMA_SLAVE_BUSWIDTH_4_BYTES = 4,
DMA_SLAVE_BUSWIDTH_8_BYTES = 8,
DMA_SLAVE_BUSWIDTH_16_BYTES = 16,
DMA_SLAVE_BUSWIDTH_32_BYTES = 32,
DMA_SLAVE_BUSWIDTH_64_BYTES = 64,
};
/**
* struct dma_slave_config - dma slave channel runtime config
* @direction: whether the data shall go in or out on this slave
* channel, right now. DMA_MEM_TO_DEV and DMA_DEV_TO_MEM are
* legal values. DEPRECATED, drivers should use the direction argument
* to the device_prep_slave_sg and device_prep_dma_cyclic functions or
* the dir field in the dma_interleaved_template structure.
* @src_addr: this is the physical address where DMA slave data
* should be read (RX), if the source is memory this argument is
* ignored.
* @dst_addr: this is the physical address where DMA slave data
* should be written (TX), if the source is memory this argument
* is ignored.
* @src_addr_width: this is the width in bytes of the source (RX)
* register where DMA data shall be read. If the source
* is memory this may be ignored depending on architecture.
* Legal values: 1, 2, 4, 8.
* @dst_addr_width: same as src_addr_width but for destination
* target (TX) mutatis mutandis.
* @src_maxburst: the maximum number of words (note: words, as in
* units of the src_addr_width member, not bytes) that can be sent
* in one burst to the device. Typically something like half the
* FIFO depth on I/O peripherals so you don't overflow it. This
* may or may not be applicable on memory sources.
* @dst_maxburst: same as src_maxburst but for destination target
* mutatis mutandis.
* @device_fc: Flow Controller Settings. Only valid for slave channels. Fill
* with 'true' if peripheral should be flow controller. Direction will be
* selected at Runtime.
* @slave_id: Slave requester id. Only valid for slave channels. The dma
* slave peripheral will have unique id as dma requester which need to be
* pass as slave config.
*
* This struct is passed in as configuration data to a DMA engine
* in order to set up a certain channel for DMA transport at runtime.
* The DMA device/engine has to provide support for an additional
* callback in the dma_device structure, device_config and this struct
* will then be passed in as an argument to the function.
*
* The rationale for adding configuration information to this struct is as
* follows: if it is likely that more than one DMA slave controllers in
* the world will support the configuration option, then make it generic.
* If not: if it is fixed so that it be sent in static from the platform
* data, then prefer to do that.
*/
struct dma_slave_config {
enum dma_transfer_direction direction;
dma_addr_t src_addr;
dma_addr_t dst_addr;
enum dma_slave_buswidth src_addr_width;
enum dma_slave_buswidth dst_addr_width;
u32 src_maxburst;
u32 dst_maxburst;
bool device_fc;
unsigned int slave_id;
};
/**
* enum dma_residue_granularity - Granularity of the reported transfer residue
* @DMA_RESIDUE_GRANULARITY_DESCRIPTOR: Residue reporting is not support. The
* DMA channel is only able to tell whether a descriptor has been completed or
* not, which means residue reporting is not supported by this channel. The
* residue field of the dma_tx_state field will always be 0.
* @DMA_RESIDUE_GRANULARITY_SEGMENT: Residue is updated after each successfully
* completed segment of the transfer (For cyclic transfers this is after each
* period). This is typically implemented by having the hardware generate an
* interrupt after each transferred segment and then the drivers updates the
* outstanding residue by the size of the segment. Another possibility is if
* the hardware supports scatter-gather and the segment descriptor has a field
* which gets set after the segment has been completed. The driver then counts
* the number of segments without the flag set to compute the residue.
* @DMA_RESIDUE_GRANULARITY_BURST: Residue is updated after each transferred
* burst. This is typically only supported if the hardware has a progress
* register of some sort (E.g. a register with the current read/write address
* or a register with the amount of bursts/beats/bytes that have been
* transferred or still need to be transferred).
*/
enum dma_residue_granularity {
DMA_RESIDUE_GRANULARITY_DESCRIPTOR = 0,
DMA_RESIDUE_GRANULARITY_SEGMENT = 1,
DMA_RESIDUE_GRANULARITY_BURST = 2,
};
/* struct dma_slave_caps - expose capabilities of a slave channel only
*
* @src_addr_widths: bit mask of src addr widths the channel supports
* @dst_addr_widths: bit mask of dstn addr widths the channel supports
* @directions: bit mask of slave direction the channel supported
* since the enum dma_transfer_direction is not defined as bits for each
* type of direction, the dma controller should fill (1 << <TYPE>) and same
* should be checked by controller as well
* @cmd_pause: true, if pause and thereby resume is supported
* @cmd_terminate: true, if terminate cmd is supported
* @residue_granularity: granularity of the reported transfer residue
* @descriptor_reuse: if a descriptor can be reused by client and
* resubmitted multiple times
*/
struct dma_slave_caps {
u32 src_addr_widths;
u32 dst_addr_widths;
u32 directions;
bool cmd_pause;
bool cmd_terminate;
enum dma_residue_granularity residue_granularity;
bool descriptor_reuse;
};
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 dmaengine_unmap_data {
u8 map_cnt;
u8 to_cnt;
u8 from_cnt;
u8 bidi_cnt;
struct device *dev;
struct kref kref;
size_t len;
dma_addr_t addr[0];
};
/**
* 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: accept the descriptor, assign ordered cookie and mark the
* descriptor pending. To be pushed on .issue_pending() call
* @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);
int (*desc_free)(struct dma_async_tx_descriptor *tx);
dma_async_tx_callback callback;
void *callback_param;
struct dmaengine_unmap_data *unmap;
#ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
struct dma_async_tx_descriptor *next;
struct dma_async_tx_descriptor *parent;
spinlock_t lock;
#endif
};
#ifdef CONFIG_DMA_ENGINE
static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
struct dmaengine_unmap_data *unmap)
{
kref_get(&unmap->kref);
tx->unmap = unmap;
}
struct dmaengine_unmap_data *
dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
#else
static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
struct dmaengine_unmap_data *unmap)
{
}
static inline struct dmaengine_unmap_data *
dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
{
return NULL;
}
static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap)
{
}
#endif
static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx)
{
if (tx->unmap) {
dmaengine_unmap_put(tx->unmap);
tx->unmap = NULL;
}
}
#ifndef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
static inline void txd_lock(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
{
BUG();
}
static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
{
}
static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
{
return NULL;
}
static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
{
return NULL;
}
#else
static inline void txd_lock(struct dma_async_tx_descriptor *txd)
{
spin_lock_bh(&txd->lock);
}
static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
{
spin_unlock_bh(&txd->lock);
}
static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
{
txd->next = next;
next->parent = txd;
}
static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
{
txd->parent = NULL;
}
static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
{
txd->next = NULL;
}
static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
{
return txd->parent;
}
static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
{
return txd->next;
}
#endif
/**
* 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;
};
/**
* enum dmaengine_alignment - defines alignment of the DMA async tx
* buffers
*/
enum dmaengine_alignment {
DMAENGINE_ALIGN_1_BYTE = 0,
DMAENGINE_ALIGN_2_BYTES = 1,
DMAENGINE_ALIGN_4_BYTES = 2,
DMAENGINE_ALIGN_8_BYTES = 3,
DMAENGINE_ALIGN_16_BYTES = 4,
DMAENGINE_ALIGN_32_BYTES = 5,
DMAENGINE_ALIGN_64_BYTES = 6,
};
/**
* 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
* @src_addr_widths: bit mask of src addr widths the device supports
* @dst_addr_widths: bit mask of dst addr widths the device supports
* @directions: bit mask of slave direction the device supports since
* the enum dma_transfer_direction is not defined as bits for
* each type of direction, the dma controller should fill (1 <<
* <TYPE>) and same should be checked by controller as well
* @residue_granularity: granularity of the transfer residue reported
* by tx_status
* @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_memset_sg: prepares a memset operation over a scatter list
* @device_prep_dma_interrupt: prepares an end of chain interrupt operation
* @device_prep_slave_sg: prepares a slave dma operation
* @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio.
* The function takes a buffer of size buf_len. The callback function will
* be called after period_len bytes have been transferred.
* @device_prep_interleaved_dma: Transfer expression in a generic way.
* @device_config: Pushes a new configuration to a channel, return 0 or an error
* code
* @device_pause: Pauses any transfer happening on a channel. Returns
* 0 or an error code
* @device_resume: Resumes any transfer on a channel previously
* paused. Returns 0 or an error code
* @device_terminate_all: Aborts all transfers on a channel. Returns 0
* or an error code
* @device_tx_status: poll for transaction completion, the optional
* txstate parameter can be supplied with a pointer to get a
* struct with auxiliary 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;
enum dmaengine_alignment copy_align;
enum dmaengine_alignment xor_align;
enum dmaengine_alignment pq_align;
enum dmaengine_alignment fill_align;
#define DMA_HAS_PQ_CONTINUE (1 << 15)
int dev_id;
struct device *dev;
u32 src_addr_widths;
u32 dst_addr_widths;
u32 directions;
enum dma_residue_granularity residue_granularity;
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 dst, 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 dst, 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_memset_sg)(
struct dma_chan *chan, struct scatterlist *sg,
unsigned int nents, int value, 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_dma_sg)(
struct dma_chan *chan,
struct scatterlist *dst_sg, unsigned int dst_nents,
struct scatterlist *src_sg, unsigned int src_nents,
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_transfer_direction direction,
unsigned long flags, void *context);
struct dma_async_tx_descriptor *(*device_prep_dma_cyclic)(
struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction direction,
unsigned long flags);
struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
struct dma_chan *chan, struct dma_interleaved_template *xt,
unsigned long flags);
int (*device_config)(struct dma_chan *chan,
struct dma_slave_config *config);
int (*device_pause)(struct dma_chan *chan);
int (*device_resume)(struct dma_chan *chan);
int (*device_terminate_all)(struct dma_chan *chan);
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 int dmaengine_slave_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
if (chan->device->device_config)
return chan->device->device_config(chan, config);
return -ENOSYS;
}
static inline bool is_slave_direction(enum dma_transfer_direction direction)
{
return (direction == DMA_MEM_TO_DEV) || (direction == DMA_DEV_TO_MEM);
}
static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single(
struct dma_chan *chan, dma_addr_t buf, size_t len,
enum dma_transfer_direction dir, unsigned long flags)
{
struct scatterlist sg;
sg_init_table(&sg, 1);
sg_dma_address(&sg) = buf;
sg_dma_len(&sg) = len;
return chan->device->device_prep_slave_sg(chan, &sg, 1,
dir, flags, NULL);
}
static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
enum dma_transfer_direction dir, unsigned long flags)
{
return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
dir, flags, NULL);
}
#ifdef CONFIG_RAPIDIO_DMA_ENGINE
struct rio_dma_ext;
static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
enum dma_transfer_direction dir, unsigned long flags,
struct rio_dma_ext *rio_ext)
{
return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
dir, flags, rio_ext);
}
#endif
static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction dir,
unsigned long flags)
{
return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
period_len, dir, flags);
}
static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma(
struct dma_chan *chan, struct dma_interleaved_template *xt,
unsigned long flags)
{
return chan->device->device_prep_interleaved_dma(chan, xt, flags);
}
static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset(
struct dma_chan *chan, dma_addr_t dest, int value, size_t len,
unsigned long flags)
{
if (!chan || !chan->device)
return NULL;
return chan->device->device_prep_dma_memset(chan, dest, value,
len, flags);
}
static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
struct dma_chan *chan,
struct scatterlist *dst_sg, unsigned int dst_nents,
struct scatterlist *src_sg, unsigned int src_nents,
unsigned long flags)
{
return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents,
src_sg, src_nents, flags);
}
static inline int dmaengine_terminate_all(struct dma_chan *chan)
{
if (chan->device->device_terminate_all)
return chan->device->device_terminate_all(chan);
return -ENOSYS;
}
static inline int dmaengine_pause(struct dma_chan *chan)
{
if (chan->device->device_pause)
return chan->device->device_pause(chan);
return -ENOSYS;
}
static inline int dmaengine_resume(struct dma_chan *chan)
{
if (chan->device->device_resume)
return chan->device->device_resume(chan);
return -ENOSYS;
}
static inline enum dma_status dmaengine_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *state)
{
return chan->device->device_tx_status(chan, cookie, state);
}
static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc)
{
return desc->tx_submit(desc);
}
static inline bool dmaengine_check_align(enum dmaengine_alignment 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 inline 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();
}
static inline size_t dmaengine_get_icg(bool inc, bool sgl, size_t icg,
size_t dir_icg)
{
if (inc) {
if (dir_icg)
return dir_icg;
else if (sgl)
return icg;
}
return 0;
}
static inline size_t dmaengine_get_dst_icg(struct dma_interleaved_template *xt,
struct data_chunk *chunk)
{
return dmaengine_get_icg(xt->dst_inc, xt->dst_sgl,
chunk->icg, chunk->dst_icg);
}
static inline size_t dmaengine_get_src_icg(struct dma_interleaved_template *xt,
struct data_chunk *chunk)
{
return dmaengine_get_icg(xt->src_inc, xt->src_sgl,
chunk->icg, chunk->src_icg);
}
/* --- 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_ASYNC_TX_DMA
#define async_dmaengine_get() dmaengine_get()
#define async_dmaengine_put() dmaengine_put()
#ifndef CONFIG_ASYNC_TX_ENABLE_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_ENABLE_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 */
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 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_each_set_bit(cap, mask.bits, DMA_TX_TYPE_END)
/**
* 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);
}
/**
* 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;
}
/**
* 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_is_tx_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_COMPLETE;
} else {
if ((cookie <= last_complete) && (cookie > last_used))
return DMA_COMPLETE;
}
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;
}
}
#ifdef CONFIG_DMA_ENGINE
struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
void dma_issue_pending_all(void);
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param);
struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
const char *name);
struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
void dma_release_channel(struct dma_chan *chan);
int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps);
#else
static inline struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type)
{
return NULL;
}
static inline enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
{
return DMA_COMPLETE;
}
static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
{
return DMA_COMPLETE;
}
static inline void dma_issue_pending_all(void)
{
}
static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param)
{
return NULL;
}
static inline struct dma_chan *dma_request_slave_channel_reason(
struct device *dev, const char *name)
{
return ERR_PTR(-ENODEV);
}
static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
const char *name)
{
return NULL;
}
static inline void dma_release_channel(struct dma_chan *chan)
{
}
static inline int dma_get_slave_caps(struct dma_chan *chan,
struct dma_slave_caps *caps)
{
return -ENXIO;
}
#endif
static inline int dmaengine_desc_set_reuse(struct dma_async_tx_descriptor *tx)
{
struct dma_slave_caps caps;
dma_get_slave_caps(tx->chan, &caps);
if (caps.descriptor_reuse) {
tx->flags |= DMA_CTRL_REUSE;
return 0;
} else {
return -EPERM;
}
}
static inline void dmaengine_desc_clear_reuse(struct dma_async_tx_descriptor *tx)
{
tx->flags &= ~DMA_CTRL_REUSE;
}
static inline bool dmaengine_desc_test_reuse(struct dma_async_tx_descriptor *tx)
{
return (tx->flags & DMA_CTRL_REUSE) == DMA_CTRL_REUSE;
}
static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc)
{
/* this is supported for reusable desc, so check that */
if (dmaengine_desc_test_reuse(desc))
return desc->desc_free(desc);
else
return -EPERM;
}
/* --- 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_get_slave_channel(struct dma_chan *chan);
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
__dma_request_slave_channel_compat(&(mask), x, y, dev, name)
static inline struct dma_chan
*__dma_request_slave_channel_compat(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param,
struct device *dev, const char *name)
{
struct dma_chan *chan;
chan = dma_request_slave_channel(dev, name);
if (chan)
return chan;
if (!fn || !fn_param)
return NULL;
return __dma_request_channel(mask, fn, fn_param);
}
#endif /* DMAENGINE_H */