1/*-
2 * Copyright (C) 2012 Intel Corporation
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27__FBSDID("$FreeBSD$");
28
29#ifndef __IOAT_H__
30#define __IOAT_H__
31
32#include <sys/param.h>
33#include <machine/bus.h>
34
35/*
36 * This file defines the public interface to the IOAT driver.
37 */
38
39/*
40 * Enables an interrupt for this operation. Typically, you would only enable
41 * this on the last operation in a group
42 */
43#define	DMA_INT_EN	0x1
44/*
45 * Like M_NOWAIT.  Operations will return NULL if they cannot allocate a
46 * descriptor without blocking.
47 */
48#define	DMA_NO_WAIT	0x2
49/*
50 * Disallow prefetching the source of the following operation.  Ordinarily, DMA
51 * operations can be pipelined on some hardware.  E.g., operation 2's source
52 * may be prefetched before operation 1 completes.
53 */
54#define	DMA_FENCE	0x4
55#define	_DMA_GENERIC_FLAGS	(DMA_INT_EN | DMA_NO_WAIT | DMA_FENCE)
56
57/*
58 * Emit a CRC32C as the result of a ioat_copy_crc() or ioat_crc().
59 */
60#define	DMA_CRC_STORE	0x8
61
62/*
63 * Compare the CRC32C of a ioat_copy_crc() or ioat_crc() against an expeceted
64 * value.  It is invalid to specify both TEST and STORE.
65 */
66#define	DMA_CRC_TEST	0x10
67#define	_DMA_CRC_TESTSTORE	(DMA_CRC_STORE | DMA_CRC_TEST)
68
69/*
70 * Use an inline comparison CRC32C or emit an inline CRC32C result.  Invalid
71 * without one of STORE or TEST.
72 */
73#define	DMA_CRC_INLINE	0x20
74#define	_DMA_CRC_FLAGS	(DMA_CRC_STORE | DMA_CRC_TEST | DMA_CRC_INLINE)
75
76/*
77 * Hardware revision number.  Different hardware revisions support different
78 * features.  For example, 3.2 cannot read from MMIO space, while 3.3 can.
79 */
80#define	IOAT_VER_3_0			0x30
81#define	IOAT_VER_3_2			0x32
82#define	IOAT_VER_3_3			0x33
83
84/*
85 * Hardware capabilities.  Different hardware revisions support different
86 * features.  It is often useful to detect specific features than try to infer
87 * them from hardware version.
88 *
89 * Different channels may support different features too; for example, 'PQ' may
90 * only be supported on the first two channels of some hardware.
91 */
92#define	IOAT_DMACAP_PB			(1 << 0)
93#define	IOAT_DMACAP_CRC			(1 << 1)
94#define	IOAT_DMACAP_MARKER_SKIP		(1 << 2)
95#define	IOAT_DMACAP_OLD_XOR		(1 << 3)
96#define	IOAT_DMACAP_DCA			(1 << 4)
97#define	IOAT_DMACAP_MOVECRC		(1 << 5)
98#define	IOAT_DMACAP_BFILL		(1 << 6)
99#define	IOAT_DMACAP_EXT_APIC		(1 << 7)
100#define	IOAT_DMACAP_XOR			(1 << 8)
101#define	IOAT_DMACAP_PQ			(1 << 9)
102#define	IOAT_DMACAP_DMA_DIF		(1 << 10)
103#define	IOAT_DMACAP_DWBES		(1 << 13)
104#define	IOAT_DMACAP_RAID16SS		(1 << 17)
105#define	IOAT_DMACAP_DMAMC		(1 << 18)
106#define	IOAT_DMACAP_CTOS		(1 << 19)
107
108#define	IOAT_DMACAP_STR \
109    "\20\24Completion_Timeout_Support\23DMA_with_Multicasting_Support" \
110    "\22RAID_Super_descriptors\16Descriptor_Write_Back_Error_Support" \
111    "\13DMA_with_DIF\12PQ\11XOR\10Extended_APIC_ID\07Block_Fill\06Move_CRC" \
112    "\05DCA\04Old_XOR\03Marker_Skipping\02CRC\01Page_Break"
113
114typedef void *bus_dmaengine_t;
115struct bus_dmadesc;
116typedef void (*bus_dmaengine_callback_t)(void *arg, int error);
117
118unsigned ioat_get_nchannels(void);
119
120/*
121 * Called first to acquire a reference to the DMA channel
122 *
123 * Flags may be M_WAITOK or M_NOWAIT.
124 */
125bus_dmaengine_t ioat_get_dmaengine(uint32_t channel_index, int flags);
126
127/* Release the DMA channel */
128void ioat_put_dmaengine(bus_dmaengine_t dmaengine);
129
130/* Check the DMA engine's HW version */
131int ioat_get_hwversion(bus_dmaengine_t dmaengine);
132size_t ioat_get_max_io_size(bus_dmaengine_t dmaengine);
133uint32_t ioat_get_capabilities(bus_dmaengine_t dmaengine);
134int ioat_get_domain(bus_dmaengine_t dmaengine, int *domain);
135
136/*
137 * Set interrupt coalescing on a DMA channel.
138 *
139 * The argument is in microseconds.  A zero value disables coalescing.  Any
140 * other value delays interrupt generation for N microseconds to provide
141 * opportunity to coalesce multiple operations into a single interrupt.
142 *
143 * Returns an error status, or zero on success.
144 *
145 * - ERANGE if the given value exceeds the delay supported by the hardware.
146 *   (All current hardware supports a maximum of 0x3fff microseconds delay.)
147 * - ENODEV if the hardware does not support interrupt coalescing.
148 */
149int ioat_set_interrupt_coalesce(bus_dmaengine_t dmaengine, uint16_t delay);
150
151/*
152 * Return the maximum supported coalescing period, for use in
153 * ioat_set_interrupt_coalesce().  If the hardware does not support coalescing,
154 * returns zero.
155 */
156uint16_t ioat_get_max_coalesce_period(bus_dmaengine_t dmaengine);
157
158/*
159 * Acquire must be called before issuing an operation to perform. Release is
160 * called after.  Multiple operations can be issued within the context of one
161 * acquire and release
162 */
163void ioat_acquire(bus_dmaengine_t dmaengine);
164void ioat_release(bus_dmaengine_t dmaengine);
165
166/*
167 * Acquire_reserve can be called to ensure there is room for N descriptors.  If
168 * it succeeds, the next N valid operations will successfully enqueue.
169 *
170 * It may fail with:
171 *   - ENXIO if the channel is in an errored state, or the driver is being
172 *     unloaded
173 *   - EAGAIN if mflags included M_NOWAIT
174 *
175 * On failure, the caller does not hold the dmaengine.
176 */
177int ioat_acquire_reserve(bus_dmaengine_t dmaengine, unsigned n, int mflags)
178    __result_use_check;
179
180/*
181 * Issue a blockfill operation.  The 64-bit pattern 'fillpattern' is written to
182 * 'len' physically contiguous bytes at 'dst'.
183 *
184 * Only supported on devices with the BFILL capability.
185 */
186struct bus_dmadesc *ioat_blockfill(bus_dmaengine_t dmaengine, bus_addr_t dst,
187    uint64_t fillpattern, bus_size_t len, bus_dmaengine_callback_t callback_fn,
188    void *callback_arg, uint32_t flags);
189
190/* Issues the copy data operation */
191struct bus_dmadesc *ioat_copy(bus_dmaengine_t dmaengine, bus_addr_t dst,
192    bus_addr_t src, bus_size_t len, bus_dmaengine_callback_t callback_fn,
193    void *callback_arg, uint32_t flags);
194
195/*
196 * Issue a copy data operation, with constraints:
197 *  - src1, src2, dst1, dst2 are all page-aligned addresses
198 *  - The quantity to copy is exactly 2 pages;
199 *  - src1 -> dst1, src2 -> dst2
200 *
201 * Why use this instead of normal _copy()?  You can copy two non-contiguous
202 * pages (src, dst, or both) with one descriptor.
203 */
204struct bus_dmadesc *ioat_copy_8k_aligned(bus_dmaengine_t dmaengine,
205    bus_addr_t dst1, bus_addr_t dst2, bus_addr_t src1, bus_addr_t src2,
206    bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
207
208/*
209 * Copy len bytes from dst to src, like ioat_copy().
210 *
211 * Additionally, accumulate a CRC32C of the data.
212 *
213 * If initialseed is not NULL, the value it points to is used to seed the
214 * initial value of the CRC32C.
215 *
216 * If flags include DMA_CRC_STORE and not DMA_CRC_INLINE, crcptr is written
217 * with the 32-bit CRC32C result (in wire format).
218 *
219 * If flags include DMA_CRC_TEST and not DMA_CRC_INLINE, the computed CRC32C is
220 * compared with the 32-bit CRC32C pointed to by crcptr.  If they do not match,
221 * a channel error is raised.
222 *
223 * If the DMA_CRC_INLINE flag is set, crcptr is ignored and the DMA engine uses
224 * the 4 bytes trailing the source data (TEST) or the destination data (STORE).
225 */
226struct bus_dmadesc *ioat_copy_crc(bus_dmaengine_t dmaengine, bus_addr_t dst,
227    bus_addr_t src, bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
228    bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
229
230/*
231 * ioat_crc() is nearly identical to ioat_copy_crc(), but does not actually
232 * move data around.
233 *
234 * Like ioat_copy_crc, ioat_crc computes a CRC32C over len bytes pointed to by
235 * src.  The flags affect its operation in the same way, with one exception:
236 *
237 * If flags includes both DMA_CRC_STORE and DMA_CRC_INLINE, the computed CRC32C
238 * is written to the 4 bytes trailing the *source* data.
239 */
240struct bus_dmadesc *ioat_crc(bus_dmaengine_t dmaengine, bus_addr_t src,
241    bus_size_t len, uint32_t *initialseed, bus_addr_t crcptr,
242    bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
243
244/*
245 * Issues a null operation. This issues the operation to the hardware, but the
246 * hardware doesn't do anything with it.
247 */
248struct bus_dmadesc *ioat_null(bus_dmaengine_t dmaengine,
249    bus_dmaengine_callback_t callback_fn, void *callback_arg, uint32_t flags);
250
251
252#endif /* __IOAT_H__ */
253
254