blob: 94a553eacdbd3b2e096aba4852c8a711e431c44e (
plain) (
tree)
|
|
/*
* 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 "dma.h"
#include "hw.h"
extern int ioat_pending_level;
/*
* 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))
/* 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
* @pending: lock free indicator for issued != head
* @dmacount: identical to 'head' except for occasionally resetting to zero
* @alloc_order: log2 of the number of allocated descriptors
* @ring: software ring buffer implementation of hardware ring
* @ring_lock: protects ring attributes
*/
struct ioat2_dma_chan {
struct ioat_chan_common base;
size_t xfercap_log;
u16 head;
u16 issued;
u16 tail;
u16 dmacount;
u16 alloc_order;
int pending;
struct ioat_ring_ent **ring;
spinlock_t ring_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_mask(struct ioat2_dma_chan *ioat)
{
return (1 << ioat->alloc_order) - 1;
}
/* count of descriptors in flight with the engine */
static inline u16 ioat2_ring_active(struct ioat2_dma_chan *ioat)
{
return (ioat->head - ioat->tail) & ioat2_ring_mask(ioat);
}
/* count of descriptors pending submission to hardware */
static inline u16 ioat2_ring_pending(struct ioat2_dma_chan *ioat)
{
return (ioat->head - ioat->issued) & ioat2_ring_mask(ioat);
}
static inline u16 ioat2_ring_space(struct ioat2_dma_chan *ioat)
{
u16 num_descs = ioat2_ring_mask(ioat) + 1;
u16 active = ioat2_ring_active(ioat);
BUG_ON(active > num_descs);
return num_descs - active;
}
/* assumes caller already checked space */
static inline u16 ioat2_desc_alloc(struct ioat2_dma_chan *ioat, u16 len)
{
ioat->head += len;
return ioat->head - len;
}
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 {
struct ioat_dma_descriptor *hw;
struct dma_async_tx_descriptor txd;
size_t len;
};
static inline struct ioat_ring_ent *
ioat2_get_ring_ent(struct ioat2_dma_chan *ioat, u16 idx)
{
return ioat->ring[idx & ioat2_ring_mask(ioat)];
}
int ioat2_dma_probe(struct ioatdma_device *dev, int dca);
int ioat3_dma_probe(struct ioatdma_device *dev, int dca);
struct dca_provider *ioat2_dca_init(struct pci_dev *pdev, void __iomem *iobase);
struct dca_provider *ioat3_dca_init(struct pci_dev *pdev, void __iomem *iobase);
#endif /* IOATDMA_V2_H */
|
