linux/drivers/dma/ioat/dma_v2.h
Dan Williams 074cc47679 ioat2,3: convert to producer/consumer locking
Use separate locks for the descriptor prep (producer) and descriptor
cleanup (consumer) paths.  Allows the producer path to run concurrently
with the cleanup path.  Inspired by Documentation/circular-buffer.txt.

Cc: David Howells <dhowells@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-05-01 15:22:55 -07:00

180 lines
5.8 KiB
C

/*
* Copyright(c) 2004 - 2009 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 IOATDMA_V2_H
#define IOATDMA_V2_H
#include <linux/dmaengine.h>
#include <linux/circ_buf.h>
#include "dma.h"
#include "hw.h"
extern int ioat_pending_level;
extern int ioat_ring_alloc_order;
/*
* workaround for IOAT ver.3.0 null descriptor issue
* (channel returns error when size is 0)
*/
#define NULL_DESC_BUFFER_SIZE 1
#define IOAT_MAX_ORDER 16
#define ioat_get_alloc_order() \
(min(ioat_ring_alloc_order, IOAT_MAX_ORDER))
#define ioat_get_max_alloc_order() \
(min(ioat_ring_max_alloc_order, IOAT_MAX_ORDER))
/* struct ioat2_dma_chan - ioat v2 / v3 channel attributes
* @base: common ioat channel parameters
* @xfercap_log; log2 of channel max transfer length (for fast division)
* @head: allocated index
* @issued: hardware notification point
* @tail: cleanup index
* @dmacount: identical to 'head' except for occasionally resetting to zero
* @alloc_order: log2 of the number of allocated descriptors
* @produce: number of descriptors to produce at submit time
* @ring: software ring buffer implementation of hardware ring
* @prep_lock: serializes descriptor preparation (producers)
*/
struct ioat2_dma_chan {
struct ioat_chan_common base;
size_t xfercap_log;
u16 head;
u16 issued;
u16 tail;
u16 dmacount;
u16 alloc_order;
u16 produce;
struct ioat_ring_ent **ring;
spinlock_t prep_lock;
};
static inline struct ioat2_dma_chan *to_ioat2_chan(struct dma_chan *c)
{
struct ioat_chan_common *chan = to_chan_common(c);
return container_of(chan, struct ioat2_dma_chan, base);
}
static inline u16 ioat2_ring_size(struct ioat2_dma_chan *ioat)
{
return 1 << ioat->alloc_order;
}
/* count of descriptors in flight with the engine */
static inline u16 ioat2_ring_active(struct ioat2_dma_chan *ioat)
{
return CIRC_CNT(ioat->head, ioat->tail, ioat2_ring_size(ioat));
}
/* count of descriptors pending submission to hardware */
static inline u16 ioat2_ring_pending(struct ioat2_dma_chan *ioat)
{
return CIRC_CNT(ioat->head, ioat->issued, ioat2_ring_size(ioat));
}
static inline u16 ioat2_ring_space(struct ioat2_dma_chan *ioat)
{
return ioat2_ring_size(ioat) - ioat2_ring_active(ioat);
}
static inline u16 ioat2_xferlen_to_descs(struct ioat2_dma_chan *ioat, size_t len)
{
u16 num_descs = len >> ioat->xfercap_log;
num_descs += !!(len & ((1 << ioat->xfercap_log) - 1));
return num_descs;
}
/**
* struct ioat_ring_ent - wrapper around hardware descriptor
* @hw: hardware DMA descriptor (for memcpy)
* @fill: hardware fill descriptor
* @xor: hardware xor descriptor
* @xor_ex: hardware xor extension descriptor
* @pq: hardware pq descriptor
* @pq_ex: hardware pq extension descriptor
* @pqu: hardware pq update descriptor
* @raw: hardware raw (un-typed) descriptor
* @txd: the generic software descriptor for all engines
* @len: total transaction length for unmap
* @result: asynchronous result of validate operations
* @id: identifier for debug
*/
struct ioat_ring_ent {
union {
struct ioat_dma_descriptor *hw;
struct ioat_fill_descriptor *fill;
struct ioat_xor_descriptor *xor;
struct ioat_xor_ext_descriptor *xor_ex;
struct ioat_pq_descriptor *pq;
struct ioat_pq_ext_descriptor *pq_ex;
struct ioat_pq_update_descriptor *pqu;
struct ioat_raw_descriptor *raw;
};
size_t len;
struct dma_async_tx_descriptor txd;
enum sum_check_flags *result;
#ifdef DEBUG
int id;
#endif
};
static inline struct ioat_ring_ent *
ioat2_get_ring_ent(struct ioat2_dma_chan *ioat, u16 idx)
{
return ioat->ring[idx & (ioat2_ring_size(ioat) - 1)];
}
static inline void ioat2_set_chainaddr(struct ioat2_dma_chan *ioat, u64 addr)
{
struct ioat_chan_common *chan = &ioat->base;
writel(addr & 0x00000000FFFFFFFF,
chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(addr >> 32,
chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
}
int __devinit ioat2_dma_probe(struct ioatdma_device *dev, int dca);
int __devinit ioat3_dma_probe(struct ioatdma_device *dev, int dca);
struct dca_provider * __devinit ioat2_dca_init(struct pci_dev *pdev, void __iomem *iobase);
struct dca_provider * __devinit ioat3_dca_init(struct pci_dev *pdev, void __iomem *iobase);
int ioat2_check_space_lock(struct ioat2_dma_chan *ioat, int num_descs);
int ioat2_enumerate_channels(struct ioatdma_device *device);
struct dma_async_tx_descriptor *
ioat2_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
dma_addr_t dma_src, size_t len, unsigned long flags);
void ioat2_issue_pending(struct dma_chan *chan);
int ioat2_alloc_chan_resources(struct dma_chan *c);
void ioat2_free_chan_resources(struct dma_chan *c);
void __ioat2_restart_chan(struct ioat2_dma_chan *ioat);
bool reshape_ring(struct ioat2_dma_chan *ioat, int order);
void __ioat2_issue_pending(struct ioat2_dma_chan *ioat);
void ioat2_cleanup_event(unsigned long data);
void ioat2_timer_event(unsigned long data);
int ioat2_quiesce(struct ioat_chan_common *chan, unsigned long tmo);
int ioat2_reset_sync(struct ioat_chan_common *chan, unsigned long tmo);
extern struct kobj_type ioat2_ktype;
extern struct kmem_cache *ioat2_cache;
#endif /* IOATDMA_V2_H */