2 * Copyright(c) 2004 - 2009 Intel Corporation. All rights reserved.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59
16 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 * The full GNU General Public License is included in this distribution in the
19 * file called COPYING.
24 #include <linux/dmaengine.h>
29 extern int ioat_pending_level;
32 * workaround for IOAT ver.3.0 null descriptor issue
33 * (channel returns error when size is 0)
35 #define NULL_DESC_BUFFER_SIZE 1
37 #define IOAT_MAX_ORDER 16
38 #define ioat_get_alloc_order() \
39 (min(ioat_ring_alloc_order, IOAT_MAX_ORDER))
40 #define ioat_get_max_alloc_order() \
41 (min(ioat_ring_max_alloc_order, IOAT_MAX_ORDER))
43 /* struct ioat2_dma_chan - ioat v2 / v3 channel attributes
44 * @base: common ioat channel parameters
45 * @xfercap_log; log2 of channel max transfer length (for fast division)
46 * @head: allocated index
47 * @issued: hardware notification point
48 * @tail: cleanup index
49 * @pending: lock free indicator for issued != head
50 * @dmacount: identical to 'head' except for occasionally resetting to zero
51 * @alloc_order: log2 of the number of allocated descriptors
52 * @ring: software ring buffer implementation of hardware ring
53 * @ring_lock: protects ring attributes
55 struct ioat2_dma_chan {
56 struct ioat_chan_common base;
64 struct ioat_ring_ent **ring;
68 static inline struct ioat2_dma_chan *to_ioat2_chan(struct dma_chan *c)
70 struct ioat_chan_common *chan = to_chan_common(c);
72 return container_of(chan, struct ioat2_dma_chan, base);
75 static inline u16 ioat2_ring_mask(struct ioat2_dma_chan *ioat)
77 return (1 << ioat->alloc_order) - 1;
80 /* count of descriptors in flight with the engine */
81 static inline u16 ioat2_ring_active(struct ioat2_dma_chan *ioat)
83 return (ioat->head - ioat->tail) & ioat2_ring_mask(ioat);
86 /* count of descriptors pending submission to hardware */
87 static inline u16 ioat2_ring_pending(struct ioat2_dma_chan *ioat)
89 return (ioat->head - ioat->issued) & ioat2_ring_mask(ioat);
92 static inline u16 ioat2_ring_space(struct ioat2_dma_chan *ioat)
94 u16 num_descs = ioat2_ring_mask(ioat) + 1;
95 u16 active = ioat2_ring_active(ioat);
97 BUG_ON(active > num_descs);
99 return num_descs - active;
102 /* assumes caller already checked space */
103 static inline u16 ioat2_desc_alloc(struct ioat2_dma_chan *ioat, u16 len)
106 return ioat->head - len;
109 static inline u16 ioat2_xferlen_to_descs(struct ioat2_dma_chan *ioat, size_t len)
111 u16 num_descs = len >> ioat->xfercap_log;
113 num_descs += !!(len & ((1 << ioat->xfercap_log) - 1));
117 struct ioat_ring_ent {
118 struct ioat_dma_descriptor *hw;
120 struct dma_async_tx_descriptor txd;
126 static inline struct ioat_ring_ent *
127 ioat2_get_ring_ent(struct ioat2_dma_chan *ioat, u16 idx)
129 return ioat->ring[idx & ioat2_ring_mask(ioat)];
132 static inline void ioat2_set_chainaddr(struct ioat2_dma_chan *ioat, u64 addr)
134 struct ioat_chan_common *chan = &ioat->base;
136 writel(addr & 0x00000000FFFFFFFF,
137 chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
139 chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
142 int __devinit ioat2_dma_probe(struct ioatdma_device *dev, int dca);
143 int __devinit ioat3_dma_probe(struct ioatdma_device *dev, int dca);
144 struct dca_provider * __devinit ioat2_dca_init(struct pci_dev *pdev, void __iomem *iobase);
145 struct dca_provider * __devinit ioat3_dca_init(struct pci_dev *pdev, void __iomem *iobase);
146 extern struct kmem_cache *ioat2_cache;
147 #endif /* IOATDMA_V2_H */